(sqrt (- (* 1/2 (+ 1 (cos (- z1 z0)))) (* (* -1/2 (+ -1 (cos (* (- z2 z3) 1)))) (* (cos z1) (cos z0)))))

Percentage Accurate: 63.7% → 99.1%
Time: 16.8s
Alternatives: 13
Speedup: 1.0×

Specification

?
\[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
(FPCore (z1 z0 z2 z3)
  :precision binary64
  (sqrt
 (-
  (* 1/2 (+ 1 (cos (- z1 z0))))
  (* (* -1/2 (+ -1 (cos (* (- z2 z3) 1)))) (* (cos z1) (cos z0))))))
double code(double z1, double z0, double z2, double z3) {
	return sqrt(((0.5 * (1.0 + cos((z1 - z0)))) - ((-0.5 * (-1.0 + cos(((z2 - z3) * 1.0)))) * (cos(z1) * cos(z0)))));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(z1, z0, z2, z3)
use fmin_fmax_functions
    real(8), intent (in) :: z1
    real(8), intent (in) :: z0
    real(8), intent (in) :: z2
    real(8), intent (in) :: z3
    code = sqrt(((0.5d0 * (1.0d0 + cos((z1 - z0)))) - (((-0.5d0) * ((-1.0d0) + cos(((z2 - z3) * 1.0d0)))) * (cos(z1) * cos(z0)))))
end function
public static double code(double z1, double z0, double z2, double z3) {
	return Math.sqrt(((0.5 * (1.0 + Math.cos((z1 - z0)))) - ((-0.5 * (-1.0 + Math.cos(((z2 - z3) * 1.0)))) * (Math.cos(z1) * Math.cos(z0)))));
}
def code(z1, z0, z2, z3):
	return math.sqrt(((0.5 * (1.0 + math.cos((z1 - z0)))) - ((-0.5 * (-1.0 + math.cos(((z2 - z3) * 1.0)))) * (math.cos(z1) * math.cos(z0)))))
function code(z1, z0, z2, z3)
	return sqrt(Float64(Float64(0.5 * Float64(1.0 + cos(Float64(z1 - z0)))) - Float64(Float64(-0.5 * Float64(-1.0 + cos(Float64(Float64(z2 - z3) * 1.0)))) * Float64(cos(z1) * cos(z0)))))
end
function tmp = code(z1, z0, z2, z3)
	tmp = sqrt(((0.5 * (1.0 + cos((z1 - z0)))) - ((-0.5 * (-1.0 + cos(((z2 - z3) * 1.0)))) * (cos(z1) * cos(z0)))));
end
code[z1_, z0_, z2_, z3_] := N[Sqrt[N[(N[(1/2 * N[(1 + N[Cos[N[(z1 - z0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(-1/2 * N[(-1 + N[Cos[N[(N[(z2 - z3), $MachinePrecision] * 1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[Cos[z1], $MachinePrecision] * N[Cos[z0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 13 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 63.7% accurate, 1.0× speedup?

\[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
(FPCore (z1 z0 z2 z3)
  :precision binary64
  (sqrt
 (-
  (* 1/2 (+ 1 (cos (- z1 z0))))
  (* (* -1/2 (+ -1 (cos (* (- z2 z3) 1)))) (* (cos z1) (cos z0))))))
double code(double z1, double z0, double z2, double z3) {
	return sqrt(((0.5 * (1.0 + cos((z1 - z0)))) - ((-0.5 * (-1.0 + cos(((z2 - z3) * 1.0)))) * (cos(z1) * cos(z0)))));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(z1, z0, z2, z3)
use fmin_fmax_functions
    real(8), intent (in) :: z1
    real(8), intent (in) :: z0
    real(8), intent (in) :: z2
    real(8), intent (in) :: z3
    code = sqrt(((0.5d0 * (1.0d0 + cos((z1 - z0)))) - (((-0.5d0) * ((-1.0d0) + cos(((z2 - z3) * 1.0d0)))) * (cos(z1) * cos(z0)))))
end function
public static double code(double z1, double z0, double z2, double z3) {
	return Math.sqrt(((0.5 * (1.0 + Math.cos((z1 - z0)))) - ((-0.5 * (-1.0 + Math.cos(((z2 - z3) * 1.0)))) * (Math.cos(z1) * Math.cos(z0)))));
}
def code(z1, z0, z2, z3):
	return math.sqrt(((0.5 * (1.0 + math.cos((z1 - z0)))) - ((-0.5 * (-1.0 + math.cos(((z2 - z3) * 1.0)))) * (math.cos(z1) * math.cos(z0)))))
function code(z1, z0, z2, z3)
	return sqrt(Float64(Float64(0.5 * Float64(1.0 + cos(Float64(z1 - z0)))) - Float64(Float64(-0.5 * Float64(-1.0 + cos(Float64(Float64(z2 - z3) * 1.0)))) * Float64(cos(z1) * cos(z0)))))
end
function tmp = code(z1, z0, z2, z3)
	tmp = sqrt(((0.5 * (1.0 + cos((z1 - z0)))) - ((-0.5 * (-1.0 + cos(((z2 - z3) * 1.0)))) * (cos(z1) * cos(z0)))));
end
code[z1_, z0_, z2_, z3_] := N[Sqrt[N[(N[(1/2 * N[(1 + N[Cos[N[(z1 - z0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(-1/2 * N[(-1 + N[Cos[N[(N[(z2 - z3), $MachinePrecision] * 1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[Cos[z1], $MachinePrecision] * N[Cos[z0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}

Alternative 1: 99.1% accurate, 0.3× speedup?

\[\sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \mathsf{304\_z0z1z2z3z4}\left(\cos z1, \sin \left(-z0\right), \cos \left(\pi \cdot \frac{1}{2}\right), \cos z0, \sin \left(\pi \cdot \frac{-1}{2}\right)\right)} \]
(FPCore (z1 z0 z2 z3)
  :precision binary64
  (sqrt
 (-
  (* 1/2 (+ (* (cos z0) (cos z1)) (+ (* (sin z0) (sin z1)) 1)))
  (*
   (*
    -1/2
    (+ -1 (* (- (* (tan z3) (tan z2)) -1) (* (cos z2) (cos z3)))))
   (304-z0z1z2z3z4
    (cos z1)
    (sin (- z0))
    (cos (* PI 1/2))
    (cos z0)
    (sin (* PI -1/2)))))))
\sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \mathsf{304\_z0z1z2z3z4}\left(\cos z1, \sin \left(-z0\right), \cos \left(\pi \cdot \frac{1}{2}\right), \cos z0, \sin \left(\pi \cdot \frac{-1}{2}\right)\right)}
Derivation
  1. Initial program 63.7%

    \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  2. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. +-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos \left(z1 - z0\right) + 1\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos \left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. lift--.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos \color{blue}{\left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    5. cos-diffN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \sin z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    6. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1} \cdot \cos z0 + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    7. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\cos z1 \cdot \color{blue}{\cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    8. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    9. associate-+l+N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    10. lower-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    11. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z1 \cdot \cos z0} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    12. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    13. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    14. lower-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \color{blue}{\left(\sin z1 \cdot \sin z0 + 1\right)}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    15. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    16. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    17. lower-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0} \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    18. lower-sin.f6479.0%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \color{blue}{\sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  3. Applied rewrites79.0%

    \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  4. Step-by-step derivation
    1. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. *-rgt-identityN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. lift--.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    5. cos-diffN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z2 \cdot \cos z3 + \sin z2 \cdot \sin z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    6. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3 \cdot \cos z2} + \sin z2 \cdot \sin z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    7. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3 \cdot \sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    8. sum-to-multN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    9. lower-unsound-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    10. lower-unsound-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}\right)} \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    11. lower-unsound-/.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \color{blue}{\frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    12. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\color{blue}{\sin z2 \cdot \sin z3}}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    13. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\color{blue}{\sin z2 \cdot \sin z3}}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    14. lower-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\color{blue}{\sin z2} \cdot \sin z3}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    15. lower-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \color{blue}{\sin z3}}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    16. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\color{blue}{\cos z2 \cdot \cos z3}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    17. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\color{blue}{\cos z2 \cdot \cos z3}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    18. lower-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\color{blue}{\cos z2} \cdot \cos z3}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    19. lower-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \color{blue}{\cos z3}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    20. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}\right) \cdot \color{blue}{\left(\cos z2 \cdot \cos z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  5. Applied rewrites99.1%

    \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}\right) \cdot \left(\cos z2 \cdot \cos z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  6. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. +-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} + 1\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. add-flipN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} - \left(\mathsf{neg}\left(1\right)\right)\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. metadata-evalN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} - \color{blue}{-1}\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    5. lower--.f6499.1%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} - -1\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    6. lift-/.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    7. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\color{blue}{\sin z2 \cdot \sin z3}}{\cos z2 \cdot \cos z3} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    8. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\color{blue}{\sin z3 \cdot \sin z2}}{\cos z2 \cdot \cos z3} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    9. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z3 \cdot \sin z2}{\color{blue}{\cos z2 \cdot \cos z3}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    10. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z3 \cdot \sin z2}{\color{blue}{\cos z3 \cdot \cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    11. times-fracN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\frac{\sin z3}{\cos z3} \cdot \frac{\sin z2}{\cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    12. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\frac{\sin z3}{\cos z3} \cdot \frac{\sin z2}{\cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    13. lift-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\color{blue}{\sin z3}}{\cos z3} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    14. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z3}{\color{blue}{\cos z3}} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    15. quot-tanN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\tan z3} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    16. lower-tan.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\tan z3} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    17. lift-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \frac{\color{blue}{\sin z2}}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    18. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \frac{\sin z2}{\color{blue}{\cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    19. quot-tanN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \color{blue}{\tan z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    20. lower-tan.f6499.1%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \color{blue}{\tan z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  7. Applied rewrites99.1%

    \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\tan z3 \cdot \tan z2 - -1\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  8. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \color{blue}{\left(\cos z1 \cdot \cos z0\right)}} \]
    2. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \color{blue}{\cos z0}\right)} \]
    3. cos-neg-revN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \color{blue}{\cos \left(\mathsf{neg}\left(z0\right)\right)}\right)} \]
    4. lift-neg.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos \color{blue}{\left(-z0\right)}\right)} \]
    5. sin-+PI/2-revN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \color{blue}{\sin \left(\left(-z0\right) + \frac{\mathsf{PI}\left(\right)}{2}\right)}\right)} \]
    6. lift-PI.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \sin \left(\left(-z0\right) + \frac{\color{blue}{\pi}}{2}\right)\right)} \]
    7. mult-flip-revN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \sin \left(\left(-z0\right) + \color{blue}{\pi \cdot \frac{1}{2}}\right)\right)} \]
    8. metadata-evalN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \sin \left(\left(-z0\right) + \pi \cdot \color{blue}{\frac{1}{2}}\right)\right)} \]
    9. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \sin \left(\left(-z0\right) + \color{blue}{\pi \cdot \frac{1}{2}}\right)\right)} \]
    10. add-flipN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \sin \color{blue}{\left(\left(-z0\right) - \left(\mathsf{neg}\left(\pi \cdot \frac{1}{2}\right)\right)\right)}\right)} \]
    11. sin-diffN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \color{blue}{\left(\sin \left(-z0\right) \cdot \cos \left(\mathsf{neg}\left(\pi \cdot \frac{1}{2}\right)\right) - \cos \left(-z0\right) \cdot \sin \left(\mathsf{neg}\left(\pi \cdot \frac{1}{2}\right)\right)\right)}\right)} \]
  9. Applied rewrites99.1%

    \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \color{blue}{\mathsf{304\_z0z1z2z3z4}\left(\cos z1, \sin \left(-z0\right), \cos \left(\pi \cdot \frac{1}{2}\right), \cos z0, \sin \left(\pi \cdot \frac{-1}{2}\right)\right)}} \]
  10. Add Preprocessing

Alternative 2: 99.1% accurate, 0.4× speedup?

\[\sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
(FPCore (z1 z0 z2 z3)
  :precision binary64
  (sqrt
 (-
  (* 1/2 (+ (* (cos z0) (cos z1)) (+ (* (sin z0) (sin z1)) 1)))
  (*
   (*
    -1/2
    (+ -1 (* (- (* (tan z3) (tan z2)) -1) (* (cos z2) (cos z3)))))
   (* (cos z1) (cos z0))))))
double code(double z1, double z0, double z2, double z3) {
	return sqrt(((0.5 * ((cos(z0) * cos(z1)) + ((sin(z0) * sin(z1)) + 1.0))) - ((-0.5 * (-1.0 + (((tan(z3) * tan(z2)) - -1.0) * (cos(z2) * cos(z3))))) * (cos(z1) * cos(z0)))));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(z1, z0, z2, z3)
use fmin_fmax_functions
    real(8), intent (in) :: z1
    real(8), intent (in) :: z0
    real(8), intent (in) :: z2
    real(8), intent (in) :: z3
    code = sqrt(((0.5d0 * ((cos(z0) * cos(z1)) + ((sin(z0) * sin(z1)) + 1.0d0))) - (((-0.5d0) * ((-1.0d0) + (((tan(z3) * tan(z2)) - (-1.0d0)) * (cos(z2) * cos(z3))))) * (cos(z1) * cos(z0)))))
end function
public static double code(double z1, double z0, double z2, double z3) {
	return Math.sqrt(((0.5 * ((Math.cos(z0) * Math.cos(z1)) + ((Math.sin(z0) * Math.sin(z1)) + 1.0))) - ((-0.5 * (-1.0 + (((Math.tan(z3) * Math.tan(z2)) - -1.0) * (Math.cos(z2) * Math.cos(z3))))) * (Math.cos(z1) * Math.cos(z0)))));
}
def code(z1, z0, z2, z3):
	return math.sqrt(((0.5 * ((math.cos(z0) * math.cos(z1)) + ((math.sin(z0) * math.sin(z1)) + 1.0))) - ((-0.5 * (-1.0 + (((math.tan(z3) * math.tan(z2)) - -1.0) * (math.cos(z2) * math.cos(z3))))) * (math.cos(z1) * math.cos(z0)))))
function code(z1, z0, z2, z3)
	return sqrt(Float64(Float64(0.5 * Float64(Float64(cos(z0) * cos(z1)) + Float64(Float64(sin(z0) * sin(z1)) + 1.0))) - Float64(Float64(-0.5 * Float64(-1.0 + Float64(Float64(Float64(tan(z3) * tan(z2)) - -1.0) * Float64(cos(z2) * cos(z3))))) * Float64(cos(z1) * cos(z0)))))
end
function tmp = code(z1, z0, z2, z3)
	tmp = sqrt(((0.5 * ((cos(z0) * cos(z1)) + ((sin(z0) * sin(z1)) + 1.0))) - ((-0.5 * (-1.0 + (((tan(z3) * tan(z2)) - -1.0) * (cos(z2) * cos(z3))))) * (cos(z1) * cos(z0)))));
end
code[z1_, z0_, z2_, z3_] := N[Sqrt[N[(N[(1/2 * N[(N[(N[Cos[z0], $MachinePrecision] * N[Cos[z1], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Sin[z0], $MachinePrecision] * N[Sin[z1], $MachinePrecision]), $MachinePrecision] + 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(-1/2 * N[(-1 + N[(N[(N[(N[Tan[z3], $MachinePrecision] * N[Tan[z2], $MachinePrecision]), $MachinePrecision] - -1), $MachinePrecision] * N[(N[Cos[z2], $MachinePrecision] * N[Cos[z3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[Cos[z1], $MachinePrecision] * N[Cos[z0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \tan z2 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}
Derivation
  1. Initial program 63.7%

    \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  2. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. +-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos \left(z1 - z0\right) + 1\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos \left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. lift--.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos \color{blue}{\left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    5. cos-diffN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \sin z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    6. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1} \cdot \cos z0 + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    7. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\cos z1 \cdot \color{blue}{\cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    8. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    9. associate-+l+N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    10. lower-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    11. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z1 \cdot \cos z0} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    12. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    13. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    14. lower-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \color{blue}{\left(\sin z1 \cdot \sin z0 + 1\right)}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    15. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    16. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    17. lower-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0} \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    18. lower-sin.f6479.0%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \color{blue}{\sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  3. Applied rewrites79.0%

    \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  4. Step-by-step derivation
    1. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. *-rgt-identityN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. lift--.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    5. cos-diffN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z2 \cdot \cos z3 + \sin z2 \cdot \sin z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    6. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3 \cdot \cos z2} + \sin z2 \cdot \sin z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    7. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3 \cdot \sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    8. sum-to-multN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    9. lower-unsound-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    10. lower-unsound-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}\right)} \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    11. lower-unsound-/.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \color{blue}{\frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    12. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\color{blue}{\sin z2 \cdot \sin z3}}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    13. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\color{blue}{\sin z2 \cdot \sin z3}}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    14. lower-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\color{blue}{\sin z2} \cdot \sin z3}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    15. lower-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \color{blue}{\sin z3}}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    16. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\color{blue}{\cos z2 \cdot \cos z3}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    17. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\color{blue}{\cos z2 \cdot \cos z3}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    18. lower-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\color{blue}{\cos z2} \cdot \cos z3}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    19. lower-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \color{blue}{\cos z3}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    20. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}\right) \cdot \color{blue}{\left(\cos z2 \cdot \cos z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  5. Applied rewrites99.1%

    \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}\right) \cdot \left(\cos z2 \cdot \cos z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  6. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. +-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} + 1\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. add-flipN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} - \left(\mathsf{neg}\left(1\right)\right)\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. metadata-evalN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} - \color{blue}{-1}\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    5. lower--.f6499.1%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} - -1\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    6. lift-/.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    7. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\color{blue}{\sin z2 \cdot \sin z3}}{\cos z2 \cdot \cos z3} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    8. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\color{blue}{\sin z3 \cdot \sin z2}}{\cos z2 \cdot \cos z3} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    9. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z3 \cdot \sin z2}{\color{blue}{\cos z2 \cdot \cos z3}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    10. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z3 \cdot \sin z2}{\color{blue}{\cos z3 \cdot \cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    11. times-fracN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\frac{\sin z3}{\cos z3} \cdot \frac{\sin z2}{\cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    12. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\frac{\sin z3}{\cos z3} \cdot \frac{\sin z2}{\cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    13. lift-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\color{blue}{\sin z3}}{\cos z3} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    14. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z3}{\color{blue}{\cos z3}} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    15. quot-tanN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\tan z3} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    16. lower-tan.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\tan z3} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    17. lift-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \frac{\color{blue}{\sin z2}}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    18. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \frac{\sin z2}{\color{blue}{\cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    19. quot-tanN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \color{blue}{\tan z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    20. lower-tan.f6499.1%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \color{blue}{\tan z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  7. Applied rewrites99.1%

    \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\tan z3 \cdot \tan z2 - -1\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  8. Add Preprocessing

Alternative 3: 99.1% accurate, 0.4× speedup?

\[\sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \cos z2 \cdot \cos z3\right) + \sin z2 \cdot \sin z3\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
(FPCore (z1 z0 z2 z3)
  :precision binary64
  (sqrt
 (-
  (* 1/2 (+ (* (cos z0) (cos z1)) (+ (* (sin z0) (sin z1)) 1)))
  (*
   (* -1/2 (+ (+ -1 (* (cos z2) (cos z3))) (* (sin z2) (sin z3))))
   (* (cos z1) (cos z0))))))
double code(double z1, double z0, double z2, double z3) {
	return sqrt(((0.5 * ((cos(z0) * cos(z1)) + ((sin(z0) * sin(z1)) + 1.0))) - ((-0.5 * ((-1.0 + (cos(z2) * cos(z3))) + (sin(z2) * sin(z3)))) * (cos(z1) * cos(z0)))));
}
module fmin_fmax_functions
    implicit none
    private
    public fmax
    public fmin

    interface fmax
        module procedure fmax88
        module procedure fmax44
        module procedure fmax84
        module procedure fmax48
    end interface
    interface fmin
        module procedure fmin88
        module procedure fmin44
        module procedure fmin84
        module procedure fmin48
    end interface
contains
    real(8) function fmax88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(4) function fmax44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, max(x, y), y /= y), x /= x)
    end function
    real(8) function fmax84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmax48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
    end function
    real(8) function fmin88(x, y) result (res)
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(4) function fmin44(x, y) result (res)
        real(4), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(y, merge(x, min(x, y), y /= y), x /= x)
    end function
    real(8) function fmin84(x, y) result(res)
        real(8), intent (in) :: x
        real(4), intent (in) :: y
        res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
    end function
    real(8) function fmin48(x, y) result(res)
        real(4), intent (in) :: x
        real(8), intent (in) :: y
        res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
    end function
end module

real(8) function code(z1, z0, z2, z3)
use fmin_fmax_functions
    real(8), intent (in) :: z1
    real(8), intent (in) :: z0
    real(8), intent (in) :: z2
    real(8), intent (in) :: z3
    code = sqrt(((0.5d0 * ((cos(z0) * cos(z1)) + ((sin(z0) * sin(z1)) + 1.0d0))) - (((-0.5d0) * (((-1.0d0) + (cos(z2) * cos(z3))) + (sin(z2) * sin(z3)))) * (cos(z1) * cos(z0)))))
end function
public static double code(double z1, double z0, double z2, double z3) {
	return Math.sqrt(((0.5 * ((Math.cos(z0) * Math.cos(z1)) + ((Math.sin(z0) * Math.sin(z1)) + 1.0))) - ((-0.5 * ((-1.0 + (Math.cos(z2) * Math.cos(z3))) + (Math.sin(z2) * Math.sin(z3)))) * (Math.cos(z1) * Math.cos(z0)))));
}
def code(z1, z0, z2, z3):
	return math.sqrt(((0.5 * ((math.cos(z0) * math.cos(z1)) + ((math.sin(z0) * math.sin(z1)) + 1.0))) - ((-0.5 * ((-1.0 + (math.cos(z2) * math.cos(z3))) + (math.sin(z2) * math.sin(z3)))) * (math.cos(z1) * math.cos(z0)))))
function code(z1, z0, z2, z3)
	return sqrt(Float64(Float64(0.5 * Float64(Float64(cos(z0) * cos(z1)) + Float64(Float64(sin(z0) * sin(z1)) + 1.0))) - Float64(Float64(-0.5 * Float64(Float64(-1.0 + Float64(cos(z2) * cos(z3))) + Float64(sin(z2) * sin(z3)))) * Float64(cos(z1) * cos(z0)))))
end
function tmp = code(z1, z0, z2, z3)
	tmp = sqrt(((0.5 * ((cos(z0) * cos(z1)) + ((sin(z0) * sin(z1)) + 1.0))) - ((-0.5 * ((-1.0 + (cos(z2) * cos(z3))) + (sin(z2) * sin(z3)))) * (cos(z1) * cos(z0)))));
end
code[z1_, z0_, z2_, z3_] := N[Sqrt[N[(N[(1/2 * N[(N[(N[Cos[z0], $MachinePrecision] * N[Cos[z1], $MachinePrecision]), $MachinePrecision] + N[(N[(N[Sin[z0], $MachinePrecision] * N[Sin[z1], $MachinePrecision]), $MachinePrecision] + 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(-1/2 * N[(N[(-1 + N[(N[Cos[z2], $MachinePrecision] * N[Cos[z3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[Sin[z2], $MachinePrecision] * N[Sin[z3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[Cos[z1], $MachinePrecision] * N[Cos[z0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \cos z2 \cdot \cos z3\right) + \sin z2 \cdot \sin z3\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}
Derivation
  1. Initial program 63.7%

    \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  2. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. +-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos \left(z1 - z0\right) + 1\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos \left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. lift--.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos \color{blue}{\left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    5. cos-diffN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \sin z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    6. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1} \cdot \cos z0 + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    7. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\cos z1 \cdot \color{blue}{\cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    8. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    9. associate-+l+N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    10. lower-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    11. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z1 \cdot \cos z0} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    12. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    13. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    14. lower-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \color{blue}{\left(\sin z1 \cdot \sin z0 + 1\right)}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    15. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    16. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    17. lower-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0} \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    18. lower-sin.f6479.0%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \color{blue}{\sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  3. Applied rewrites79.0%

    \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  4. Step-by-step derivation
    1. lift-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \color{blue}{\left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)}\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. lift-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. lift-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. *-rgt-identityN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    5. lift--.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    6. cos-diffN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z2 \cdot \cos z3 + \sin z2 \cdot \sin z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    7. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3 \cdot \cos z2} + \sin z2 \cdot \sin z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    8. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3 \cdot \sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    9. associate-+r+N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \color{blue}{\left(\left(-1 + \cos z3 \cdot \cos z2\right) + \sin z3 \cdot \sin z2\right)}\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    10. lower-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \color{blue}{\left(\left(-1 + \cos z3 \cdot \cos z2\right) + \sin z3 \cdot \sin z2\right)}\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    11. lower-+.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\color{blue}{\left(-1 + \cos z3 \cdot \cos z2\right)} + \sin z3 \cdot \sin z2\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    12. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \color{blue}{\cos z2 \cdot \cos z3}\right) + \sin z3 \cdot \sin z2\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    13. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \color{blue}{\cos z2 \cdot \cos z3}\right) + \sin z3 \cdot \sin z2\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    14. lower-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \color{blue}{\cos z2} \cdot \cos z3\right) + \sin z3 \cdot \sin z2\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    15. lower-cos.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \cos z2 \cdot \color{blue}{\cos z3}\right) + \sin z3 \cdot \sin z2\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    16. *-commutativeN/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \cos z2 \cdot \cos z3\right) + \color{blue}{\sin z2 \cdot \sin z3}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    17. lower-*.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \cos z2 \cdot \cos z3\right) + \color{blue}{\sin z2 \cdot \sin z3}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    18. lower-sin.f64N/A

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \cos z2 \cdot \cos z3\right) + \color{blue}{\sin z2} \cdot \sin z3\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    19. lower-sin.f6499.1%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(\left(-1 + \cos z2 \cdot \cos z3\right) + \sin z2 \cdot \color{blue}{\sin z3}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  5. Applied rewrites99.1%

    \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \color{blue}{\left(\left(-1 + \cos z2 \cdot \cos z3\right) + \sin z2 \cdot \sin z3\right)}\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
  6. Add Preprocessing

Alternative 4: 88.8% accurate, 0.3× speedup?

\[\begin{array}{l} t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\ t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\ t_2 := t\_0 \cdot t\_1\\ t_3 := \sqrt{\frac{1}{2} + \left(\mathsf{304\_z0z1z2z3z4}\left(\frac{1}{2}, t\_1, t\_0, \sin \left(\mathsf{min}\left(z1, z0\right)\right), \sin \left(-\mathsf{max}\left(z1, z0\right)\right)\right) - \left(t\_2 \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)}\\ \mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\ \;\;\;\;t\_3\\ \mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\ \;\;\;\;\sqrt{\left(\cos \left(\mathsf{max}\left(z1, z0\right) - \mathsf{min}\left(z1, z0\right)\right) - -1\right) \cdot \frac{1}{2} - \left(\left(\left(\tan z2 \cdot \tan z3 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right) - 1\right) \cdot \frac{-1}{2}\right) \cdot t\_2}\\ \mathbf{else}:\\ \;\;\;\;t\_3\\ \end{array} \]
(FPCore (z1 z0 z2 z3)
  :precision binary64
  (let* ((t_0 (cos (fmax z1 z0)))
       (t_1 (cos (fmin z1 z0)))
       (t_2 (* t_0 t_1))
       (t_3
        (sqrt
         (+
          1/2
          (-
           (304-z0z1z2z3z4
            1/2
            t_1
            t_0
            (sin (fmin z1 z0))
            (sin (- (fmax z1 z0))))
           (* (* t_2 -1/2) (- (cos (- z3 z2)) 1)))))))
  (if (<= (fmax z1 z0) -6165521680034609/604462909807314587353088)
    t_3
    (if (<= (fmax z1 z0) 7791904696734915/590295810358705651712)
      (sqrt
       (-
        (* (- (cos (- (fmax z1 z0) (fmin z1 z0))) -1) 1/2)
        (*
         (*
          (- (* (- (* (tan z2) (tan z3)) -1) (* (cos z2) (cos z3))) 1)
          -1/2)
         t_2)))
      t_3))))
\begin{array}{l}
t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\
t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\
t_2 := t\_0 \cdot t\_1\\
t_3 := \sqrt{\frac{1}{2} + \left(\mathsf{304\_z0z1z2z3z4}\left(\frac{1}{2}, t\_1, t\_0, \sin \left(\mathsf{min}\left(z1, z0\right)\right), \sin \left(-\mathsf{max}\left(z1, z0\right)\right)\right) - \left(t\_2 \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)}\\
\mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\
\;\;\;\;t\_3\\

\mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\
\;\;\;\;\sqrt{\left(\cos \left(\mathsf{max}\left(z1, z0\right) - \mathsf{min}\left(z1, z0\right)\right) - -1\right) \cdot \frac{1}{2} - \left(\left(\left(\tan z2 \cdot \tan z3 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right) - 1\right) \cdot \frac{-1}{2}\right) \cdot t\_2}\\

\mathbf{else}:\\
\;\;\;\;t\_3\\


\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z0 < -1.02e-8 or 1.3200000000000001e-5 < z0

    1. Initial program 63.7%

      \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
      2. lift-*.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      4. distribute-rgt-inN/A

        \[\leadsto \sqrt{\color{blue}{\left(1 \cdot \frac{1}{2} + \cos \left(z1 - z0\right) \cdot \frac{1}{2}\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      5. metadata-evalN/A

        \[\leadsto \sqrt{\left(\color{blue}{\frac{1}{2}} + \cos \left(z1 - z0\right) \cdot \frac{1}{2}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      6. associate--l+N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
      7. lower-+.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
      8. lower--.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} + \color{blue}{\left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
    3. Applied rewrites63.8%

      \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z0 - z1\right) \cdot \frac{1}{2} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)}} \]
    4. Applied rewrites79.0%

      \[\leadsto \sqrt{\frac{1}{2} + \left(\color{blue}{\mathsf{304\_z0z1z2z3z4}\left(\frac{1}{2}, \cos z1, \cos z0, \sin z1, \sin \left(-z0\right)\right)} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)} \]

    if -1.02e-8 < z0 < 1.3200000000000001e-5

    1. Initial program 63.7%

      \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. Step-by-step derivation
      1. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. +-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos \left(z1 - z0\right) + 1\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos \left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      4. lift--.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos \color{blue}{\left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      5. cos-diffN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \sin z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      6. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1} \cdot \cos z0 + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      7. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\cos z1 \cdot \color{blue}{\cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      8. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      9. associate-+l+N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      10. lower-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      11. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z1 \cdot \cos z0} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      12. *-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      13. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      14. lower-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \color{blue}{\left(\sin z1 \cdot \sin z0 + 1\right)}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      15. *-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      16. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      17. lower-sin.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0} \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      18. lower-sin.f6479.0%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \color{blue}{\sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. Applied rewrites79.0%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. Step-by-step derivation
      1. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. *-rgt-identityN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      4. lift--.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      5. cos-diffN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z2 \cdot \cos z3 + \sin z2 \cdot \sin z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      6. *-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3 \cdot \cos z2} + \sin z2 \cdot \sin z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      7. *-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3 \cdot \sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      8. sum-to-multN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      9. lower-unsound-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      10. lower-unsound-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}\right)} \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      11. lower-unsound-/.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \color{blue}{\frac{\sin z3 \cdot \sin z2}{\cos z3 \cdot \cos z2}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      12. *-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\color{blue}{\sin z2 \cdot \sin z3}}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      13. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\color{blue}{\sin z2 \cdot \sin z3}}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      14. lower-sin.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\color{blue}{\sin z2} \cdot \sin z3}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      15. lower-sin.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \color{blue}{\sin z3}}{\cos z3 \cdot \cos z2}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      16. *-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\color{blue}{\cos z2 \cdot \cos z3}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      17. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\color{blue}{\cos z2 \cdot \cos z3}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      18. lower-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\color{blue}{\cos z2} \cdot \cos z3}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      19. lower-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \color{blue}{\cos z3}}\right) \cdot \left(\cos z3 \cdot \cos z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      20. *-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}\right) \cdot \color{blue}{\left(\cos z2 \cdot \cos z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    5. Applied rewrites99.1%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}\right) \cdot \left(\cos z2 \cdot \cos z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    6. Step-by-step derivation
      1. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(1 + \frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. +-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} + 1\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. add-flipN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} - \left(\mathsf{neg}\left(1\right)\right)\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      4. metadata-evalN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} - \color{blue}{-1}\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      5. lower--.f6499.1%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3} - -1\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      6. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\frac{\sin z2 \cdot \sin z3}{\cos z2 \cdot \cos z3}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      7. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\color{blue}{\sin z2 \cdot \sin z3}}{\cos z2 \cdot \cos z3} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      8. *-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\color{blue}{\sin z3 \cdot \sin z2}}{\cos z2 \cdot \cos z3} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      9. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z3 \cdot \sin z2}{\color{blue}{\cos z2 \cdot \cos z3}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      10. *-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z3 \cdot \sin z2}{\color{blue}{\cos z3 \cdot \cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      11. times-fracN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\frac{\sin z3}{\cos z3} \cdot \frac{\sin z2}{\cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      12. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\frac{\sin z3}{\cos z3} \cdot \frac{\sin z2}{\cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      13. lift-sin.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\color{blue}{\sin z3}}{\cos z3} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      14. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\frac{\sin z3}{\color{blue}{\cos z3}} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      15. quot-tanN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\tan z3} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      16. lower-tan.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\tan z3} \cdot \frac{\sin z2}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      17. lift-sin.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \frac{\color{blue}{\sin z2}}{\cos z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      18. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \frac{\sin z2}{\color{blue}{\cos z2}} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      19. quot-tanN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \color{blue}{\tan z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      20. lower-tan.f6499.1%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\tan z3 \cdot \color{blue}{\tan z2} - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    7. Applied rewrites99.1%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\tan z3 \cdot \tan z2 - -1\right)} \cdot \left(\cos z2 \cdot \cos z3\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    8. Step-by-step derivation
      1. Applied rewrites78.8%

        \[\leadsto \sqrt{\color{blue}{\left(\cos \left(z0 - z1\right) - -1\right) \cdot \frac{1}{2} - \left(\left(\left(\tan z2 \cdot \tan z3 - -1\right) \cdot \left(\cos z2 \cdot \cos z3\right) - 1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos z0 \cdot \cos z1\right)}} \]
    9. Recombined 2 regimes into one program.
    10. Add Preprocessing

    Alternative 5: 88.8% accurate, 0.3× speedup?

    \[\begin{array}{l} t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\ t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\ t_2 := \sqrt{\frac{1}{2} + \left(\mathsf{304\_z0z1z2z3z4}\left(\frac{1}{2}, t\_1, t\_0, \sin \left(\mathsf{min}\left(z1, z0\right)\right), \sin \left(-\mathsf{max}\left(z1, z0\right)\right)\right) - \left(\left(t\_0 \cdot t\_1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)}\\ \mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\ \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(\mathsf{min}\left(z1, z0\right) - \mathsf{max}\left(z1, z0\right)\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(t\_1 \cdot t\_0\right)}\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \]
    (FPCore (z1 z0 z2 z3)
      :precision binary64
      (let* ((t_0 (cos (fmax z1 z0)))
           (t_1 (cos (fmin z1 z0)))
           (t_2
            (sqrt
             (+
              1/2
              (-
               (304-z0z1z2z3z4
                1/2
                t_1
                t_0
                (sin (fmin z1 z0))
                (sin (- (fmax z1 z0))))
               (* (* (* t_0 t_1) -1/2) (- (cos (- z3 z2)) 1)))))))
      (if (<= (fmax z1 z0) -6165521680034609/604462909807314587353088)
        t_2
        (if (<= (fmax z1 z0) 7791904696734915/590295810358705651712)
          (sqrt
           (-
            (* 1/2 (+ 1 (cos (- (fmin z1 z0) (fmax z1 z0)))))
            (*
             (*
              -1/2
              (+ -1 (+ (* (cos z3) (cos z2)) (* (sin z3) (sin z2)))))
             (* t_1 t_0))))
          t_2))))
    \begin{array}{l}
    t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\
    t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\
    t_2 := \sqrt{\frac{1}{2} + \left(\mathsf{304\_z0z1z2z3z4}\left(\frac{1}{2}, t\_1, t\_0, \sin \left(\mathsf{min}\left(z1, z0\right)\right), \sin \left(-\mathsf{max}\left(z1, z0\right)\right)\right) - \left(\left(t\_0 \cdot t\_1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)}\\
    \mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\
    \;\;\;\;t\_2\\
    
    \mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\
    \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(\mathsf{min}\left(z1, z0\right) - \mathsf{max}\left(z1, z0\right)\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(t\_1 \cdot t\_0\right)}\\
    
    \mathbf{else}:\\
    \;\;\;\;t\_2\\
    
    
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if z0 < -1.02e-8 or 1.3200000000000001e-5 < z0

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \sqrt{\color{blue}{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\color{blue}{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        3. lift-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        4. distribute-rgt-inN/A

          \[\leadsto \sqrt{\color{blue}{\left(1 \cdot \frac{1}{2} + \cos \left(z1 - z0\right) \cdot \frac{1}{2}\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        5. metadata-evalN/A

          \[\leadsto \sqrt{\left(\color{blue}{\frac{1}{2}} + \cos \left(z1 - z0\right) \cdot \frac{1}{2}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        6. associate--l+N/A

          \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
        7. lower-+.f64N/A

          \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
        8. lower--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} + \color{blue}{\left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
      3. Applied rewrites63.8%

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z0 - z1\right) \cdot \frac{1}{2} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)}} \]
      4. Applied rewrites79.0%

        \[\leadsto \sqrt{\frac{1}{2} + \left(\color{blue}{\mathsf{304\_z0z1z2z3z4}\left(\frac{1}{2}, \cos z1, \cos z0, \sin z1, \sin \left(-z0\right)\right)} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)} \]

      if -1.02e-8 < z0 < 1.3200000000000001e-5

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        3. *-rgt-identityN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        4. lift--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        5. sub-negate-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\mathsf{neg}\left(\left(z3 - z2\right)\right)\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        6. cos-negN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(z3 - z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        7. cos-diffN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        8. cos-neg-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right)} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        9. lower-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        10. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        11. cos-neg-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        12. lower-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        13. lower-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \color{blue}{\cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        14. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3 \cdot \sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        15. lower-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3} \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        16. lower-sin.f6478.8%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \color{blue}{\sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. Applied rewrites78.8%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. Recombined 2 regimes into one program.
    4. Add Preprocessing

    Alternative 6: 88.8% accurate, 0.3× speedup?

    \[\begin{array}{l} t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\ t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\ t_2 := \sin \left(\mathsf{max}\left(z1, z0\right)\right)\\ t_3 := \sin \left(\mathsf{min}\left(z1, z0\right)\right)\\ t_4 := \cos \left(z3 - z2\right) - 1\\ t_5 := t\_0 \cdot t\_1\\ \mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\ \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(t\_5 + \left(t\_2 \cdot t\_3 + 1\right)\right) - t\_4 \cdot \left(\left(\frac{-1}{2} \cdot t\_0\right) \cdot t\_1\right)}\\ \mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\ \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(\mathsf{min}\left(z1, z0\right) - \mathsf{max}\left(z1, z0\right)\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(t\_1 \cdot t\_0\right)}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \left(t\_5 + t\_3 \cdot t\_2\right)\right) - \left(t\_1 \cdot \left(t\_4 \cdot \frac{-1}{2}\right)\right) \cdot t\_0}\\ \end{array} \]
    (FPCore (z1 z0 z2 z3)
      :precision binary64
      (let* ((t_0 (cos (fmax z1 z0)))
           (t_1 (cos (fmin z1 z0)))
           (t_2 (sin (fmax z1 z0)))
           (t_3 (sin (fmin z1 z0)))
           (t_4 (- (cos (- z3 z2)) 1))
           (t_5 (* t_0 t_1)))
      (if (<= (fmax z1 z0) -6165521680034609/604462909807314587353088)
        (sqrt
         (-
          (* 1/2 (+ t_5 (+ (* t_2 t_3) 1)))
          (* t_4 (* (* -1/2 t_0) t_1))))
        (if (<= (fmax z1 z0) 7791904696734915/590295810358705651712)
          (sqrt
           (-
            (* 1/2 (+ 1 (cos (- (fmin z1 z0) (fmax z1 z0)))))
            (*
             (*
              -1/2
              (+ -1 (+ (* (cos z3) (cos z2)) (* (sin z3) (sin z2)))))
             (* t_1 t_0))))
          (sqrt
           (-
            (* 1/2 (+ 1 (+ t_5 (* t_3 t_2))))
            (* (* t_1 (* t_4 -1/2)) t_0)))))))
    double code(double z1, double z0, double z2, double z3) {
    	double t_0 = cos(fmax(z1, z0));
    	double t_1 = cos(fmin(z1, z0));
    	double t_2 = sin(fmax(z1, z0));
    	double t_3 = sin(fmin(z1, z0));
    	double t_4 = cos((z3 - z2)) - 1.0;
    	double t_5 = t_0 * t_1;
    	double tmp;
    	if (fmax(z1, z0) <= -1.02e-8) {
    		tmp = sqrt(((0.5 * (t_5 + ((t_2 * t_3) + 1.0))) - (t_4 * ((-0.5 * t_0) * t_1))));
    	} else if (fmax(z1, z0) <= 1.32e-5) {
    		tmp = sqrt(((0.5 * (1.0 + cos((fmin(z1, z0) - fmax(z1, z0))))) - ((-0.5 * (-1.0 + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (t_1 * t_0))));
    	} else {
    		tmp = sqrt(((0.5 * (1.0 + (t_5 + (t_3 * t_2)))) - ((t_1 * (t_4 * -0.5)) * t_0)));
    	}
    	return tmp;
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(z1, z0, z2, z3)
    use fmin_fmax_functions
        real(8), intent (in) :: z1
        real(8), intent (in) :: z0
        real(8), intent (in) :: z2
        real(8), intent (in) :: z3
        real(8) :: t_0
        real(8) :: t_1
        real(8) :: t_2
        real(8) :: t_3
        real(8) :: t_4
        real(8) :: t_5
        real(8) :: tmp
        t_0 = cos(fmax(z1, z0))
        t_1 = cos(fmin(z1, z0))
        t_2 = sin(fmax(z1, z0))
        t_3 = sin(fmin(z1, z0))
        t_4 = cos((z3 - z2)) - 1.0d0
        t_5 = t_0 * t_1
        if (fmax(z1, z0) <= (-1.02d-8)) then
            tmp = sqrt(((0.5d0 * (t_5 + ((t_2 * t_3) + 1.0d0))) - (t_4 * (((-0.5d0) * t_0) * t_1))))
        else if (fmax(z1, z0) <= 1.32d-5) then
            tmp = sqrt(((0.5d0 * (1.0d0 + cos((fmin(z1, z0) - fmax(z1, z0))))) - (((-0.5d0) * ((-1.0d0) + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (t_1 * t_0))))
        else
            tmp = sqrt(((0.5d0 * (1.0d0 + (t_5 + (t_3 * t_2)))) - ((t_1 * (t_4 * (-0.5d0))) * t_0)))
        end if
        code = tmp
    end function
    
    public static double code(double z1, double z0, double z2, double z3) {
    	double t_0 = Math.cos(fmax(z1, z0));
    	double t_1 = Math.cos(fmin(z1, z0));
    	double t_2 = Math.sin(fmax(z1, z0));
    	double t_3 = Math.sin(fmin(z1, z0));
    	double t_4 = Math.cos((z3 - z2)) - 1.0;
    	double t_5 = t_0 * t_1;
    	double tmp;
    	if (fmax(z1, z0) <= -1.02e-8) {
    		tmp = Math.sqrt(((0.5 * (t_5 + ((t_2 * t_3) + 1.0))) - (t_4 * ((-0.5 * t_0) * t_1))));
    	} else if (fmax(z1, z0) <= 1.32e-5) {
    		tmp = Math.sqrt(((0.5 * (1.0 + Math.cos((fmin(z1, z0) - fmax(z1, z0))))) - ((-0.5 * (-1.0 + ((Math.cos(z3) * Math.cos(z2)) + (Math.sin(z3) * Math.sin(z2))))) * (t_1 * t_0))));
    	} else {
    		tmp = Math.sqrt(((0.5 * (1.0 + (t_5 + (t_3 * t_2)))) - ((t_1 * (t_4 * -0.5)) * t_0)));
    	}
    	return tmp;
    }
    
    def code(z1, z0, z2, z3):
    	t_0 = math.cos(fmax(z1, z0))
    	t_1 = math.cos(fmin(z1, z0))
    	t_2 = math.sin(fmax(z1, z0))
    	t_3 = math.sin(fmin(z1, z0))
    	t_4 = math.cos((z3 - z2)) - 1.0
    	t_5 = t_0 * t_1
    	tmp = 0
    	if fmax(z1, z0) <= -1.02e-8:
    		tmp = math.sqrt(((0.5 * (t_5 + ((t_2 * t_3) + 1.0))) - (t_4 * ((-0.5 * t_0) * t_1))))
    	elif fmax(z1, z0) <= 1.32e-5:
    		tmp = math.sqrt(((0.5 * (1.0 + math.cos((fmin(z1, z0) - fmax(z1, z0))))) - ((-0.5 * (-1.0 + ((math.cos(z3) * math.cos(z2)) + (math.sin(z3) * math.sin(z2))))) * (t_1 * t_0))))
    	else:
    		tmp = math.sqrt(((0.5 * (1.0 + (t_5 + (t_3 * t_2)))) - ((t_1 * (t_4 * -0.5)) * t_0)))
    	return tmp
    
    function code(z1, z0, z2, z3)
    	t_0 = cos(fmax(z1, z0))
    	t_1 = cos(fmin(z1, z0))
    	t_2 = sin(fmax(z1, z0))
    	t_3 = sin(fmin(z1, z0))
    	t_4 = Float64(cos(Float64(z3 - z2)) - 1.0)
    	t_5 = Float64(t_0 * t_1)
    	tmp = 0.0
    	if (fmax(z1, z0) <= -1.02e-8)
    		tmp = sqrt(Float64(Float64(0.5 * Float64(t_5 + Float64(Float64(t_2 * t_3) + 1.0))) - Float64(t_4 * Float64(Float64(-0.5 * t_0) * t_1))));
    	elseif (fmax(z1, z0) <= 1.32e-5)
    		tmp = sqrt(Float64(Float64(0.5 * Float64(1.0 + cos(Float64(fmin(z1, z0) - fmax(z1, z0))))) - Float64(Float64(-0.5 * Float64(-1.0 + Float64(Float64(cos(z3) * cos(z2)) + Float64(sin(z3) * sin(z2))))) * Float64(t_1 * t_0))));
    	else
    		tmp = sqrt(Float64(Float64(0.5 * Float64(1.0 + Float64(t_5 + Float64(t_3 * t_2)))) - Float64(Float64(t_1 * Float64(t_4 * -0.5)) * t_0)));
    	end
    	return tmp
    end
    
    function tmp_2 = code(z1, z0, z2, z3)
    	t_0 = cos(max(z1, z0));
    	t_1 = cos(min(z1, z0));
    	t_2 = sin(max(z1, z0));
    	t_3 = sin(min(z1, z0));
    	t_4 = cos((z3 - z2)) - 1.0;
    	t_5 = t_0 * t_1;
    	tmp = 0.0;
    	if (max(z1, z0) <= -1.02e-8)
    		tmp = sqrt(((0.5 * (t_5 + ((t_2 * t_3) + 1.0))) - (t_4 * ((-0.5 * t_0) * t_1))));
    	elseif (max(z1, z0) <= 1.32e-5)
    		tmp = sqrt(((0.5 * (1.0 + cos((min(z1, z0) - max(z1, z0))))) - ((-0.5 * (-1.0 + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (t_1 * t_0))));
    	else
    		tmp = sqrt(((0.5 * (1.0 + (t_5 + (t_3 * t_2)))) - ((t_1 * (t_4 * -0.5)) * t_0)));
    	end
    	tmp_2 = tmp;
    end
    
    code[z1_, z0_, z2_, z3_] := Block[{t$95$0 = N[Cos[N[Max[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[Cos[N[Min[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sin[N[Max[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[Sin[N[Min[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(N[Cos[N[(z3 - z2), $MachinePrecision]], $MachinePrecision] - 1), $MachinePrecision]}, Block[{t$95$5 = N[(t$95$0 * t$95$1), $MachinePrecision]}, If[LessEqual[N[Max[z1, z0], $MachinePrecision], -6165521680034609/604462909807314587353088], N[Sqrt[N[(N[(1/2 * N[(t$95$5 + N[(N[(t$95$2 * t$95$3), $MachinePrecision] + 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(t$95$4 * N[(N[(-1/2 * t$95$0), $MachinePrecision] * t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], If[LessEqual[N[Max[z1, z0], $MachinePrecision], 7791904696734915/590295810358705651712], N[Sqrt[N[(N[(1/2 * N[(1 + N[Cos[N[(N[Min[z1, z0], $MachinePrecision] - N[Max[z1, z0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(-1/2 * N[(-1 + N[(N[(N[Cos[z3], $MachinePrecision] * N[Cos[z2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[z3], $MachinePrecision] * N[Sin[z2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(t$95$1 * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[Sqrt[N[(N[(1/2 * N[(1 + N[(t$95$5 + N[(t$95$3 * t$95$2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(t$95$1 * N[(t$95$4 * -1/2), $MachinePrecision]), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]]]]]]]
    
    \begin{array}{l}
    t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\
    t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\
    t_2 := \sin \left(\mathsf{max}\left(z1, z0\right)\right)\\
    t_3 := \sin \left(\mathsf{min}\left(z1, z0\right)\right)\\
    t_4 := \cos \left(z3 - z2\right) - 1\\
    t_5 := t\_0 \cdot t\_1\\
    \mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\
    \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(t\_5 + \left(t\_2 \cdot t\_3 + 1\right)\right) - t\_4 \cdot \left(\left(\frac{-1}{2} \cdot t\_0\right) \cdot t\_1\right)}\\
    
    \mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\
    \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(\mathsf{min}\left(z1, z0\right) - \mathsf{max}\left(z1, z0\right)\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(t\_1 \cdot t\_0\right)}\\
    
    \mathbf{else}:\\
    \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \left(t\_5 + t\_3 \cdot t\_2\right)\right) - \left(t\_1 \cdot \left(t\_4 \cdot \frac{-1}{2}\right)\right) \cdot t\_0}\\
    
    
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if z0 < -1.02e-8

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        2. +-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos \left(z1 - z0\right) + 1\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        3. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos \left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        4. lift--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos \color{blue}{\left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        5. cos-diffN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \sin z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        6. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1} \cdot \cos z0 + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        7. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\cos z1 \cdot \color{blue}{\cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        8. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        9. associate-+l+N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        10. lower-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        11. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z1 \cdot \cos z0} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        12. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        13. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        14. lower-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \color{blue}{\left(\sin z1 \cdot \sin z0 + 1\right)}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        15. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        16. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        17. lower-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0} \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        18. lower-sin.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \color{blue}{\sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. Applied rewrites79.0%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      4. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right)} \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        3. associate-*l*N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\frac{-1}{2} \cdot \left(\left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
        4. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(\left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right) \cdot \frac{-1}{2}}} \]
        5. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right) \cdot \color{blue}{\left(\cos z1 \cdot \cos z0\right)}\right) \cdot \frac{-1}{2}} \]
        6. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right) \cdot \color{blue}{\left(\cos z0 \cdot \cos z1\right)}\right) \cdot \frac{-1}{2}} \]
        7. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right) \cdot \color{blue}{\left(\cos z0 \cdot \cos z1\right)}\right) \cdot \frac{-1}{2}} \]
        8. associate-*r*N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right) \cdot \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right)}} \]
        9. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right) \cdot \color{blue}{\left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right)}} \]
        10. lower-*.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right) \cdot \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right)}} \]
      5. Applied rewrites79.0%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(\cos \left(z3 - z2\right) - 1\right) \cdot \left(\left(\frac{-1}{2} \cdot \cos z0\right) \cdot \cos z1\right)}} \]

      if -1.02e-8 < z0 < 1.3200000000000001e-5

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        3. *-rgt-identityN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        4. lift--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        5. sub-negate-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\mathsf{neg}\left(\left(z3 - z2\right)\right)\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        6. cos-negN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(z3 - z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        7. cos-diffN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        8. cos-neg-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right)} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        9. lower-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        10. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        11. cos-neg-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        12. lower-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        13. lower-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \color{blue}{\cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        14. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3 \cdot \sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        15. lower-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3} \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        16. lower-sin.f6478.8%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \color{blue}{\sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. Applied rewrites78.8%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]

      if 1.3200000000000001e-5 < z0

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \color{blue}{\left(\cos z1 \cdot \cos z0\right)}} \]
        3. associate-*r*N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \cos z1\right) \cdot \cos z0}} \]
        4. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \cos z1\right) \cdot \cos z0}} \]
      3. Applied rewrites63.7%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0}} \]
      4. Step-by-step derivation
        1. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\cos \left(z1 - z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        2. lift--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \color{blue}{\left(z1 - z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        3. cos-diffN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \sin z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        4. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z1} \cdot \cos z0 + \sin z1 \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        5. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \color{blue}{\cos z0} + \sin z1 \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        6. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z1 \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        7. lift-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \color{blue}{\sin z1} \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        8. lift-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \color{blue}{\sin z0}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        9. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \color{blue}{\sin z0 \cdot \sin z1}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        10. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \color{blue}{\sin z0 \cdot \sin z1}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        11. lower-+.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z0 \cdot \sin z1\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        12. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z0 \cdot \sin z1\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        13. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z0 \cdot \cos z1} + \sin z0 \cdot \sin z1\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        14. lift-*.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z0 \cdot \cos z1} + \sin z0 \cdot \sin z1\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        15. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z0 \cdot \cos z1 + \color{blue}{\sin z0 \cdot \sin z1}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        16. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z0 \cdot \cos z1 + \color{blue}{\sin z1 \cdot \sin z0}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        17. lower-*.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z0 \cdot \cos z1 + \color{blue}{\sin z1 \cdot \sin z0}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
      5. Applied rewrites79.0%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\left(\cos z0 \cdot \cos z1 + \sin z1 \cdot \sin z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
    3. Recombined 3 regimes into one program.
    4. Add Preprocessing

    Alternative 7: 88.8% accurate, 0.3× speedup?

    \[\begin{array}{l} t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\ t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\ t_2 := \sin \left(\mathsf{max}\left(z1, z0\right)\right)\\ t_3 := \sin \left(\mathsf{min}\left(z1, z0\right)\right)\\ t_4 := \left(t\_1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot t\_0\\ t_5 := t\_0 \cdot t\_1\\ \mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\ \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(t\_5 + \left(t\_2 \cdot t\_3 + 1\right)\right) - t\_4}\\ \mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\ \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(\mathsf{min}\left(z1, z0\right) - \mathsf{max}\left(z1, z0\right)\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(t\_1 \cdot t\_0\right)}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \left(t\_5 + t\_3 \cdot t\_2\right)\right) - t\_4}\\ \end{array} \]
    (FPCore (z1 z0 z2 z3)
      :precision binary64
      (let* ((t_0 (cos (fmax z1 z0)))
           (t_1 (cos (fmin z1 z0)))
           (t_2 (sin (fmax z1 z0)))
           (t_3 (sin (fmin z1 z0)))
           (t_4 (* (* t_1 (* (- (cos (- z3 z2)) 1) -1/2)) t_0))
           (t_5 (* t_0 t_1)))
      (if (<= (fmax z1 z0) -6165521680034609/604462909807314587353088)
        (sqrt (- (* 1/2 (+ t_5 (+ (* t_2 t_3) 1))) t_4))
        (if (<= (fmax z1 z0) 7791904696734915/590295810358705651712)
          (sqrt
           (-
            (* 1/2 (+ 1 (cos (- (fmin z1 z0) (fmax z1 z0)))))
            (*
             (*
              -1/2
              (+ -1 (+ (* (cos z3) (cos z2)) (* (sin z3) (sin z2)))))
             (* t_1 t_0))))
          (sqrt (- (* 1/2 (+ 1 (+ t_5 (* t_3 t_2)))) t_4))))))
    double code(double z1, double z0, double z2, double z3) {
    	double t_0 = cos(fmax(z1, z0));
    	double t_1 = cos(fmin(z1, z0));
    	double t_2 = sin(fmax(z1, z0));
    	double t_3 = sin(fmin(z1, z0));
    	double t_4 = (t_1 * ((cos((z3 - z2)) - 1.0) * -0.5)) * t_0;
    	double t_5 = t_0 * t_1;
    	double tmp;
    	if (fmax(z1, z0) <= -1.02e-8) {
    		tmp = sqrt(((0.5 * (t_5 + ((t_2 * t_3) + 1.0))) - t_4));
    	} else if (fmax(z1, z0) <= 1.32e-5) {
    		tmp = sqrt(((0.5 * (1.0 + cos((fmin(z1, z0) - fmax(z1, z0))))) - ((-0.5 * (-1.0 + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (t_1 * t_0))));
    	} else {
    		tmp = sqrt(((0.5 * (1.0 + (t_5 + (t_3 * t_2)))) - t_4));
    	}
    	return tmp;
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(z1, z0, z2, z3)
    use fmin_fmax_functions
        real(8), intent (in) :: z1
        real(8), intent (in) :: z0
        real(8), intent (in) :: z2
        real(8), intent (in) :: z3
        real(8) :: t_0
        real(8) :: t_1
        real(8) :: t_2
        real(8) :: t_3
        real(8) :: t_4
        real(8) :: t_5
        real(8) :: tmp
        t_0 = cos(fmax(z1, z0))
        t_1 = cos(fmin(z1, z0))
        t_2 = sin(fmax(z1, z0))
        t_3 = sin(fmin(z1, z0))
        t_4 = (t_1 * ((cos((z3 - z2)) - 1.0d0) * (-0.5d0))) * t_0
        t_5 = t_0 * t_1
        if (fmax(z1, z0) <= (-1.02d-8)) then
            tmp = sqrt(((0.5d0 * (t_5 + ((t_2 * t_3) + 1.0d0))) - t_4))
        else if (fmax(z1, z0) <= 1.32d-5) then
            tmp = sqrt(((0.5d0 * (1.0d0 + cos((fmin(z1, z0) - fmax(z1, z0))))) - (((-0.5d0) * ((-1.0d0) + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (t_1 * t_0))))
        else
            tmp = sqrt(((0.5d0 * (1.0d0 + (t_5 + (t_3 * t_2)))) - t_4))
        end if
        code = tmp
    end function
    
    public static double code(double z1, double z0, double z2, double z3) {
    	double t_0 = Math.cos(fmax(z1, z0));
    	double t_1 = Math.cos(fmin(z1, z0));
    	double t_2 = Math.sin(fmax(z1, z0));
    	double t_3 = Math.sin(fmin(z1, z0));
    	double t_4 = (t_1 * ((Math.cos((z3 - z2)) - 1.0) * -0.5)) * t_0;
    	double t_5 = t_0 * t_1;
    	double tmp;
    	if (fmax(z1, z0) <= -1.02e-8) {
    		tmp = Math.sqrt(((0.5 * (t_5 + ((t_2 * t_3) + 1.0))) - t_4));
    	} else if (fmax(z1, z0) <= 1.32e-5) {
    		tmp = Math.sqrt(((0.5 * (1.0 + Math.cos((fmin(z1, z0) - fmax(z1, z0))))) - ((-0.5 * (-1.0 + ((Math.cos(z3) * Math.cos(z2)) + (Math.sin(z3) * Math.sin(z2))))) * (t_1 * t_0))));
    	} else {
    		tmp = Math.sqrt(((0.5 * (1.0 + (t_5 + (t_3 * t_2)))) - t_4));
    	}
    	return tmp;
    }
    
    def code(z1, z0, z2, z3):
    	t_0 = math.cos(fmax(z1, z0))
    	t_1 = math.cos(fmin(z1, z0))
    	t_2 = math.sin(fmax(z1, z0))
    	t_3 = math.sin(fmin(z1, z0))
    	t_4 = (t_1 * ((math.cos((z3 - z2)) - 1.0) * -0.5)) * t_0
    	t_5 = t_0 * t_1
    	tmp = 0
    	if fmax(z1, z0) <= -1.02e-8:
    		tmp = math.sqrt(((0.5 * (t_5 + ((t_2 * t_3) + 1.0))) - t_4))
    	elif fmax(z1, z0) <= 1.32e-5:
    		tmp = math.sqrt(((0.5 * (1.0 + math.cos((fmin(z1, z0) - fmax(z1, z0))))) - ((-0.5 * (-1.0 + ((math.cos(z3) * math.cos(z2)) + (math.sin(z3) * math.sin(z2))))) * (t_1 * t_0))))
    	else:
    		tmp = math.sqrt(((0.5 * (1.0 + (t_5 + (t_3 * t_2)))) - t_4))
    	return tmp
    
    function code(z1, z0, z2, z3)
    	t_0 = cos(fmax(z1, z0))
    	t_1 = cos(fmin(z1, z0))
    	t_2 = sin(fmax(z1, z0))
    	t_3 = sin(fmin(z1, z0))
    	t_4 = Float64(Float64(t_1 * Float64(Float64(cos(Float64(z3 - z2)) - 1.0) * -0.5)) * t_0)
    	t_5 = Float64(t_0 * t_1)
    	tmp = 0.0
    	if (fmax(z1, z0) <= -1.02e-8)
    		tmp = sqrt(Float64(Float64(0.5 * Float64(t_5 + Float64(Float64(t_2 * t_3) + 1.0))) - t_4));
    	elseif (fmax(z1, z0) <= 1.32e-5)
    		tmp = sqrt(Float64(Float64(0.5 * Float64(1.0 + cos(Float64(fmin(z1, z0) - fmax(z1, z0))))) - Float64(Float64(-0.5 * Float64(-1.0 + Float64(Float64(cos(z3) * cos(z2)) + Float64(sin(z3) * sin(z2))))) * Float64(t_1 * t_0))));
    	else
    		tmp = sqrt(Float64(Float64(0.5 * Float64(1.0 + Float64(t_5 + Float64(t_3 * t_2)))) - t_4));
    	end
    	return tmp
    end
    
    function tmp_2 = code(z1, z0, z2, z3)
    	t_0 = cos(max(z1, z0));
    	t_1 = cos(min(z1, z0));
    	t_2 = sin(max(z1, z0));
    	t_3 = sin(min(z1, z0));
    	t_4 = (t_1 * ((cos((z3 - z2)) - 1.0) * -0.5)) * t_0;
    	t_5 = t_0 * t_1;
    	tmp = 0.0;
    	if (max(z1, z0) <= -1.02e-8)
    		tmp = sqrt(((0.5 * (t_5 + ((t_2 * t_3) + 1.0))) - t_4));
    	elseif (max(z1, z0) <= 1.32e-5)
    		tmp = sqrt(((0.5 * (1.0 + cos((min(z1, z0) - max(z1, z0))))) - ((-0.5 * (-1.0 + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (t_1 * t_0))));
    	else
    		tmp = sqrt(((0.5 * (1.0 + (t_5 + (t_3 * t_2)))) - t_4));
    	end
    	tmp_2 = tmp;
    end
    
    code[z1_, z0_, z2_, z3_] := Block[{t$95$0 = N[Cos[N[Max[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[Cos[N[Min[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sin[N[Max[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$3 = N[Sin[N[Min[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$4 = N[(N[(t$95$1 * N[(N[(N[Cos[N[(z3 - z2), $MachinePrecision]], $MachinePrecision] - 1), $MachinePrecision] * -1/2), $MachinePrecision]), $MachinePrecision] * t$95$0), $MachinePrecision]}, Block[{t$95$5 = N[(t$95$0 * t$95$1), $MachinePrecision]}, If[LessEqual[N[Max[z1, z0], $MachinePrecision], -6165521680034609/604462909807314587353088], N[Sqrt[N[(N[(1/2 * N[(t$95$5 + N[(N[(t$95$2 * t$95$3), $MachinePrecision] + 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t$95$4), $MachinePrecision]], $MachinePrecision], If[LessEqual[N[Max[z1, z0], $MachinePrecision], 7791904696734915/590295810358705651712], N[Sqrt[N[(N[(1/2 * N[(1 + N[Cos[N[(N[Min[z1, z0], $MachinePrecision] - N[Max[z1, z0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(-1/2 * N[(-1 + N[(N[(N[Cos[z3], $MachinePrecision] * N[Cos[z2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[z3], $MachinePrecision] * N[Sin[z2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(t$95$1 * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[Sqrt[N[(N[(1/2 * N[(1 + N[(t$95$5 + N[(t$95$3 * t$95$2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - t$95$4), $MachinePrecision]], $MachinePrecision]]]]]]]]]
    
    \begin{array}{l}
    t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\
    t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\
    t_2 := \sin \left(\mathsf{max}\left(z1, z0\right)\right)\\
    t_3 := \sin \left(\mathsf{min}\left(z1, z0\right)\right)\\
    t_4 := \left(t\_1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot t\_0\\
    t_5 := t\_0 \cdot t\_1\\
    \mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\
    \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(t\_5 + \left(t\_2 \cdot t\_3 + 1\right)\right) - t\_4}\\
    
    \mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\
    \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(\mathsf{min}\left(z1, z0\right) - \mathsf{max}\left(z1, z0\right)\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(t\_1 \cdot t\_0\right)}\\
    
    \mathbf{else}:\\
    \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \left(t\_5 + t\_3 \cdot t\_2\right)\right) - t\_4}\\
    
    
    \end{array}
    
    Derivation
    1. Split input into 3 regimes
    2. if z0 < -1.02e-8

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        2. +-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos \left(z1 - z0\right) + 1\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        3. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos \left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        4. lift--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos \color{blue}{\left(z1 - z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        5. cos-diffN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \sin z0\right)} + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        6. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1} \cdot \cos z0 + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        7. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\cos z1 \cdot \color{blue}{\cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        8. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z1 \cdot \sin z0\right) + 1\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        9. associate-+l+N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        10. lower-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z1 \cdot \cos z0 + \left(\sin z1 \cdot \sin z0 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        11. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z1 \cdot \cos z0} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        12. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        13. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{\cos z0 \cdot \cos z1} + \left(\sin z1 \cdot \sin z0 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        14. lower-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \color{blue}{\left(\sin z1 \cdot \sin z0 + 1\right)}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        15. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        16. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0 \cdot \sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        17. lower-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\color{blue}{\sin z0} \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        18. lower-sin.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \color{blue}{\sin z1} + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. Applied rewrites79.0%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      4. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \color{blue}{\left(\cos z1 \cdot \cos z0\right)}} \]
        3. associate-*r*N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \cos z1\right) \cdot \cos z0}} \]
        4. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \cos z1\right) \cdot \cos z0}} \]
      5. Applied rewrites79.0%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\cos z0 \cdot \cos z1 + \left(\sin z0 \cdot \sin z1 + 1\right)\right) - \color{blue}{\left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0}} \]

      if -1.02e-8 < z0 < 1.3200000000000001e-5

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        3. *-rgt-identityN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        4. lift--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        5. sub-negate-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\mathsf{neg}\left(\left(z3 - z2\right)\right)\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        6. cos-negN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(z3 - z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        7. cos-diffN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        8. cos-neg-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right)} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        9. lower-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        10. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        11. cos-neg-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        12. lower-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        13. lower-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \color{blue}{\cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        14. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3 \cdot \sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        15. lower-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3} \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        16. lower-sin.f6478.8%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \color{blue}{\sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. Applied rewrites78.8%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]

      if 1.3200000000000001e-5 < z0

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \color{blue}{\left(\cos z1 \cdot \cos z0\right)}} \]
        3. associate-*r*N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \cos z1\right) \cdot \cos z0}} \]
        4. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \cos z1\right) \cdot \cos z0}} \]
      3. Applied rewrites63.7%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0}} \]
      4. Step-by-step derivation
        1. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\cos \left(z1 - z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        2. lift--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \color{blue}{\left(z1 - z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        3. cos-diffN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \sin z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        4. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z1} \cdot \cos z0 + \sin z1 \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        5. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \color{blue}{\cos z0} + \sin z1 \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        6. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z1 \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        7. lift-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \color{blue}{\sin z1} \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        8. lift-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \color{blue}{\sin z0}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        9. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \color{blue}{\sin z0 \cdot \sin z1}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        10. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \color{blue}{\sin z0 \cdot \sin z1}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        11. lower-+.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z0 \cdot \sin z1\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        12. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z0 \cdot \sin z1\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        13. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z0 \cdot \cos z1} + \sin z0 \cdot \sin z1\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        14. lift-*.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z0 \cdot \cos z1} + \sin z0 \cdot \sin z1\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        15. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z0 \cdot \cos z1 + \color{blue}{\sin z0 \cdot \sin z1}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        16. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z0 \cdot \cos z1 + \color{blue}{\sin z1 \cdot \sin z0}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        17. lower-*.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z0 \cdot \cos z1 + \color{blue}{\sin z1 \cdot \sin z0}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
      5. Applied rewrites79.0%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\left(\cos z0 \cdot \cos z1 + \sin z1 \cdot \sin z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
    3. Recombined 3 regimes into one program.
    4. Add Preprocessing

    Alternative 8: 88.8% accurate, 0.3× speedup?

    \[\begin{array}{l} t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\ t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\ t_2 := \sqrt{\frac{1}{2} \cdot \left(1 + \left(t\_0 \cdot t\_1 + \sin \left(\mathsf{min}\left(z1, z0\right)\right) \cdot \sin \left(\mathsf{max}\left(z1, z0\right)\right)\right)\right) - \left(t\_1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot t\_0}\\ \mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\ \;\;\;\;t\_2\\ \mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\ \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(\mathsf{min}\left(z1, z0\right) - \mathsf{max}\left(z1, z0\right)\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(t\_1 \cdot t\_0\right)}\\ \mathbf{else}:\\ \;\;\;\;t\_2\\ \end{array} \]
    (FPCore (z1 z0 z2 z3)
      :precision binary64
      (let* ((t_0 (cos (fmax z1 z0)))
           (t_1 (cos (fmin z1 z0)))
           (t_2
            (sqrt
             (-
              (*
               1/2
               (+
                1
                (+
                 (* t_0 t_1)
                 (* (sin (fmin z1 z0)) (sin (fmax z1 z0))))))
              (* (* t_1 (* (- (cos (- z3 z2)) 1) -1/2)) t_0)))))
      (if (<= (fmax z1 z0) -6165521680034609/604462909807314587353088)
        t_2
        (if (<= (fmax z1 z0) 7791904696734915/590295810358705651712)
          (sqrt
           (-
            (* 1/2 (+ 1 (cos (- (fmin z1 z0) (fmax z1 z0)))))
            (*
             (*
              -1/2
              (+ -1 (+ (* (cos z3) (cos z2)) (* (sin z3) (sin z2)))))
             (* t_1 t_0))))
          t_2))))
    double code(double z1, double z0, double z2, double z3) {
    	double t_0 = cos(fmax(z1, z0));
    	double t_1 = cos(fmin(z1, z0));
    	double t_2 = sqrt(((0.5 * (1.0 + ((t_0 * t_1) + (sin(fmin(z1, z0)) * sin(fmax(z1, z0)))))) - ((t_1 * ((cos((z3 - z2)) - 1.0) * -0.5)) * t_0)));
    	double tmp;
    	if (fmax(z1, z0) <= -1.02e-8) {
    		tmp = t_2;
    	} else if (fmax(z1, z0) <= 1.32e-5) {
    		tmp = sqrt(((0.5 * (1.0 + cos((fmin(z1, z0) - fmax(z1, z0))))) - ((-0.5 * (-1.0 + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (t_1 * t_0))));
    	} else {
    		tmp = t_2;
    	}
    	return tmp;
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(z1, z0, z2, z3)
    use fmin_fmax_functions
        real(8), intent (in) :: z1
        real(8), intent (in) :: z0
        real(8), intent (in) :: z2
        real(8), intent (in) :: z3
        real(8) :: t_0
        real(8) :: t_1
        real(8) :: t_2
        real(8) :: tmp
        t_0 = cos(fmax(z1, z0))
        t_1 = cos(fmin(z1, z0))
        t_2 = sqrt(((0.5d0 * (1.0d0 + ((t_0 * t_1) + (sin(fmin(z1, z0)) * sin(fmax(z1, z0)))))) - ((t_1 * ((cos((z3 - z2)) - 1.0d0) * (-0.5d0))) * t_0)))
        if (fmax(z1, z0) <= (-1.02d-8)) then
            tmp = t_2
        else if (fmax(z1, z0) <= 1.32d-5) then
            tmp = sqrt(((0.5d0 * (1.0d0 + cos((fmin(z1, z0) - fmax(z1, z0))))) - (((-0.5d0) * ((-1.0d0) + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (t_1 * t_0))))
        else
            tmp = t_2
        end if
        code = tmp
    end function
    
    public static double code(double z1, double z0, double z2, double z3) {
    	double t_0 = Math.cos(fmax(z1, z0));
    	double t_1 = Math.cos(fmin(z1, z0));
    	double t_2 = Math.sqrt(((0.5 * (1.0 + ((t_0 * t_1) + (Math.sin(fmin(z1, z0)) * Math.sin(fmax(z1, z0)))))) - ((t_1 * ((Math.cos((z3 - z2)) - 1.0) * -0.5)) * t_0)));
    	double tmp;
    	if (fmax(z1, z0) <= -1.02e-8) {
    		tmp = t_2;
    	} else if (fmax(z1, z0) <= 1.32e-5) {
    		tmp = Math.sqrt(((0.5 * (1.0 + Math.cos((fmin(z1, z0) - fmax(z1, z0))))) - ((-0.5 * (-1.0 + ((Math.cos(z3) * Math.cos(z2)) + (Math.sin(z3) * Math.sin(z2))))) * (t_1 * t_0))));
    	} else {
    		tmp = t_2;
    	}
    	return tmp;
    }
    
    def code(z1, z0, z2, z3):
    	t_0 = math.cos(fmax(z1, z0))
    	t_1 = math.cos(fmin(z1, z0))
    	t_2 = math.sqrt(((0.5 * (1.0 + ((t_0 * t_1) + (math.sin(fmin(z1, z0)) * math.sin(fmax(z1, z0)))))) - ((t_1 * ((math.cos((z3 - z2)) - 1.0) * -0.5)) * t_0)))
    	tmp = 0
    	if fmax(z1, z0) <= -1.02e-8:
    		tmp = t_2
    	elif fmax(z1, z0) <= 1.32e-5:
    		tmp = math.sqrt(((0.5 * (1.0 + math.cos((fmin(z1, z0) - fmax(z1, z0))))) - ((-0.5 * (-1.0 + ((math.cos(z3) * math.cos(z2)) + (math.sin(z3) * math.sin(z2))))) * (t_1 * t_0))))
    	else:
    		tmp = t_2
    	return tmp
    
    function code(z1, z0, z2, z3)
    	t_0 = cos(fmax(z1, z0))
    	t_1 = cos(fmin(z1, z0))
    	t_2 = sqrt(Float64(Float64(0.5 * Float64(1.0 + Float64(Float64(t_0 * t_1) + Float64(sin(fmin(z1, z0)) * sin(fmax(z1, z0)))))) - Float64(Float64(t_1 * Float64(Float64(cos(Float64(z3 - z2)) - 1.0) * -0.5)) * t_0)))
    	tmp = 0.0
    	if (fmax(z1, z0) <= -1.02e-8)
    		tmp = t_2;
    	elseif (fmax(z1, z0) <= 1.32e-5)
    		tmp = sqrt(Float64(Float64(0.5 * Float64(1.0 + cos(Float64(fmin(z1, z0) - fmax(z1, z0))))) - Float64(Float64(-0.5 * Float64(-1.0 + Float64(Float64(cos(z3) * cos(z2)) + Float64(sin(z3) * sin(z2))))) * Float64(t_1 * t_0))));
    	else
    		tmp = t_2;
    	end
    	return tmp
    end
    
    function tmp_2 = code(z1, z0, z2, z3)
    	t_0 = cos(max(z1, z0));
    	t_1 = cos(min(z1, z0));
    	t_2 = sqrt(((0.5 * (1.0 + ((t_0 * t_1) + (sin(min(z1, z0)) * sin(max(z1, z0)))))) - ((t_1 * ((cos((z3 - z2)) - 1.0) * -0.5)) * t_0)));
    	tmp = 0.0;
    	if (max(z1, z0) <= -1.02e-8)
    		tmp = t_2;
    	elseif (max(z1, z0) <= 1.32e-5)
    		tmp = sqrt(((0.5 * (1.0 + cos((min(z1, z0) - max(z1, z0))))) - ((-0.5 * (-1.0 + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (t_1 * t_0))));
    	else
    		tmp = t_2;
    	end
    	tmp_2 = tmp;
    end
    
    code[z1_, z0_, z2_, z3_] := Block[{t$95$0 = N[Cos[N[Max[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[Cos[N[Min[z1, z0], $MachinePrecision]], $MachinePrecision]}, Block[{t$95$2 = N[Sqrt[N[(N[(1/2 * N[(1 + N[(N[(t$95$0 * t$95$1), $MachinePrecision] + N[(N[Sin[N[Min[z1, z0], $MachinePrecision]], $MachinePrecision] * N[Sin[N[Max[z1, z0], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(t$95$1 * N[(N[(N[Cos[N[(z3 - z2), $MachinePrecision]], $MachinePrecision] - 1), $MachinePrecision] * -1/2), $MachinePrecision]), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[N[Max[z1, z0], $MachinePrecision], -6165521680034609/604462909807314587353088], t$95$2, If[LessEqual[N[Max[z1, z0], $MachinePrecision], 7791904696734915/590295810358705651712], N[Sqrt[N[(N[(1/2 * N[(1 + N[Cos[N[(N[Min[z1, z0], $MachinePrecision] - N[Max[z1, z0], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(-1/2 * N[(-1 + N[(N[(N[Cos[z3], $MachinePrecision] * N[Cos[z2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[z3], $MachinePrecision] * N[Sin[z2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(t$95$1 * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], t$95$2]]]]]
    
    \begin{array}{l}
    t_0 := \cos \left(\mathsf{max}\left(z1, z0\right)\right)\\
    t_1 := \cos \left(\mathsf{min}\left(z1, z0\right)\right)\\
    t_2 := \sqrt{\frac{1}{2} \cdot \left(1 + \left(t\_0 \cdot t\_1 + \sin \left(\mathsf{min}\left(z1, z0\right)\right) \cdot \sin \left(\mathsf{max}\left(z1, z0\right)\right)\right)\right) - \left(t\_1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot t\_0}\\
    \mathbf{if}\;\mathsf{max}\left(z1, z0\right) \leq \frac{-6165521680034609}{604462909807314587353088}:\\
    \;\;\;\;t\_2\\
    
    \mathbf{elif}\;\mathsf{max}\left(z1, z0\right) \leq \frac{7791904696734915}{590295810358705651712}:\\
    \;\;\;\;\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(\mathsf{min}\left(z1, z0\right) - \mathsf{max}\left(z1, z0\right)\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(t\_1 \cdot t\_0\right)}\\
    
    \mathbf{else}:\\
    \;\;\;\;t\_2\\
    
    
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if z0 < -1.02e-8 or 1.3200000000000001e-5 < z0

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \color{blue}{\left(\cos z1 \cdot \cos z0\right)}} \]
        3. associate-*r*N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \cos z1\right) \cdot \cos z0}} \]
        4. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \cos z1\right) \cdot \cos z0}} \]
      3. Applied rewrites63.7%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \color{blue}{\left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0}} \]
      4. Step-by-step derivation
        1. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\cos \left(z1 - z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        2. lift--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \color{blue}{\left(z1 - z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        3. cos-diffN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \sin z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        4. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z1} \cdot \cos z0 + \sin z1 \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        5. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \color{blue}{\cos z0} + \sin z1 \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        6. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z1 \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        7. lift-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \color{blue}{\sin z1} \cdot \sin z0\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        8. lift-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \sin z1 \cdot \color{blue}{\sin z0}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        9. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \color{blue}{\sin z0 \cdot \sin z1}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        10. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z1 \cdot \cos z0 + \color{blue}{\sin z0 \cdot \sin z1}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        11. lower-+.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\left(\cos z1 \cdot \cos z0 + \sin z0 \cdot \sin z1\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        12. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z1 \cdot \cos z0} + \sin z0 \cdot \sin z1\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        13. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z0 \cdot \cos z1} + \sin z0 \cdot \sin z1\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        14. lift-*.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\color{blue}{\cos z0 \cdot \cos z1} + \sin z0 \cdot \sin z1\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        15. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z0 \cdot \cos z1 + \color{blue}{\sin z0 \cdot \sin z1}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        16. *-commutativeN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z0 \cdot \cos z1 + \color{blue}{\sin z1 \cdot \sin z0}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
        17. lower-*.f6479.0%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \left(\cos z0 \cdot \cos z1 + \color{blue}{\sin z1 \cdot \sin z0}\right)\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]
      5. Applied rewrites79.0%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\left(\cos z0 \cdot \cos z1 + \sin z1 \cdot \sin z0\right)}\right) - \left(\cos z1 \cdot \left(\left(\cos \left(z3 - z2\right) - 1\right) \cdot \frac{-1}{2}\right)\right) \cdot \cos z0} \]

      if -1.02e-8 < z0 < 1.3200000000000001e-5

      1. Initial program 63.7%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. Step-by-step derivation
        1. lift-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        2. lift-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        3. *-rgt-identityN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        4. lift--.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        5. sub-negate-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\mathsf{neg}\left(\left(z3 - z2\right)\right)\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        6. cos-negN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(z3 - z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        7. cos-diffN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        8. cos-neg-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right)} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        9. lower-+.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        10. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        11. cos-neg-revN/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        12. lower-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        13. lower-cos.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \color{blue}{\cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        14. lower-*.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3 \cdot \sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        15. lower-sin.f64N/A

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3} \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
        16. lower-sin.f6478.8%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \color{blue}{\sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. Applied rewrites78.8%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. Recombined 2 regimes into one program.
    4. Add Preprocessing

    Alternative 9: 78.8% accurate, 0.6× speedup?

    \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    (FPCore (z1 z0 z2 z3)
      :precision binary64
      (sqrt
     (-
      (* 1/2 (+ 1 (cos (- z1 z0))))
      (*
       (* -1/2 (+ -1 (+ (* (cos z3) (cos z2)) (* (sin z3) (sin z2)))))
       (* (cos z1) (cos z0))))))
    double code(double z1, double z0, double z2, double z3) {
    	return sqrt(((0.5 * (1.0 + cos((z1 - z0)))) - ((-0.5 * (-1.0 + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (cos(z1) * cos(z0)))));
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(z1, z0, z2, z3)
    use fmin_fmax_functions
        real(8), intent (in) :: z1
        real(8), intent (in) :: z0
        real(8), intent (in) :: z2
        real(8), intent (in) :: z3
        code = sqrt(((0.5d0 * (1.0d0 + cos((z1 - z0)))) - (((-0.5d0) * ((-1.0d0) + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (cos(z1) * cos(z0)))))
    end function
    
    public static double code(double z1, double z0, double z2, double z3) {
    	return Math.sqrt(((0.5 * (1.0 + Math.cos((z1 - z0)))) - ((-0.5 * (-1.0 + ((Math.cos(z3) * Math.cos(z2)) + (Math.sin(z3) * Math.sin(z2))))) * (Math.cos(z1) * Math.cos(z0)))));
    }
    
    def code(z1, z0, z2, z3):
    	return math.sqrt(((0.5 * (1.0 + math.cos((z1 - z0)))) - ((-0.5 * (-1.0 + ((math.cos(z3) * math.cos(z2)) + (math.sin(z3) * math.sin(z2))))) * (math.cos(z1) * math.cos(z0)))))
    
    function code(z1, z0, z2, z3)
    	return sqrt(Float64(Float64(0.5 * Float64(1.0 + cos(Float64(z1 - z0)))) - Float64(Float64(-0.5 * Float64(-1.0 + Float64(Float64(cos(z3) * cos(z2)) + Float64(sin(z3) * sin(z2))))) * Float64(cos(z1) * cos(z0)))))
    end
    
    function tmp = code(z1, z0, z2, z3)
    	tmp = sqrt(((0.5 * (1.0 + cos((z1 - z0)))) - ((-0.5 * (-1.0 + ((cos(z3) * cos(z2)) + (sin(z3) * sin(z2))))) * (cos(z1) * cos(z0)))));
    end
    
    code[z1_, z0_, z2_, z3_] := N[Sqrt[N[(N[(1/2 * N[(1 + N[Cos[N[(z1 - z0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(-1/2 * N[(-1 + N[(N[(N[Cos[z3], $MachinePrecision] * N[Cos[z2], $MachinePrecision]), $MachinePrecision] + N[(N[Sin[z3], $MachinePrecision] * N[Sin[z2], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[Cos[z1], $MachinePrecision] * N[Cos[z0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
    
    \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}
    
    Derivation
    1. Initial program 63.7%

      \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. Step-by-step derivation
      1. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      2. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\left(z2 - z3\right) \cdot 1\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. *-rgt-identityN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      4. lift--.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(z2 - z3\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      5. sub-negate-revN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \color{blue}{\left(\mathsf{neg}\left(\left(z3 - z2\right)\right)\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      6. cos-negN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\cos \left(z3 - z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      7. cos-diffN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      8. cos-neg-revN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right)} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      9. lower-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      10. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos \left(\mathsf{neg}\left(z3\right)\right) \cdot \cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      11. cos-neg-revN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      12. lower-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\color{blue}{\cos z3} \cdot \cos z2 + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      13. lower-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \color{blue}{\cos z2} + \sin z3 \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      14. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3 \cdot \sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      15. lower-sin.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \color{blue}{\sin z3} \cdot \sin z2\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      16. lower-sin.f6478.8%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \color{blue}{\sin z2}\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    3. Applied rewrites78.8%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \color{blue}{\left(\cos z3 \cdot \cos z2 + \sin z3 \cdot \sin z2\right)}\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    4. Add Preprocessing

    Alternative 10: 64.3% accurate, 1.0× speedup?

    \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z0 + z1\right) + \cos \left(z0 - z1\right)\right) \cdot \frac{1}{2}\right)} \]
    (FPCore (z1 z0 z2 z3)
      :precision binary64
      (sqrt
     (-
      (* 1/2 (+ 1 (cos (- z1 z0))))
      (*
       (* -1/2 (+ -1 (cos (* (- z2 z3) 1))))
       (* (+ (cos (+ z0 z1)) (cos (- z0 z1))) 1/2)))))
    double code(double z1, double z0, double z2, double z3) {
    	return sqrt(((0.5 * (1.0 + cos((z1 - z0)))) - ((-0.5 * (-1.0 + cos(((z2 - z3) * 1.0)))) * ((cos((z0 + z1)) + cos((z0 - z1))) * 0.5))));
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(z1, z0, z2, z3)
    use fmin_fmax_functions
        real(8), intent (in) :: z1
        real(8), intent (in) :: z0
        real(8), intent (in) :: z2
        real(8), intent (in) :: z3
        code = sqrt(((0.5d0 * (1.0d0 + cos((z1 - z0)))) - (((-0.5d0) * ((-1.0d0) + cos(((z2 - z3) * 1.0d0)))) * ((cos((z0 + z1)) + cos((z0 - z1))) * 0.5d0))))
    end function
    
    public static double code(double z1, double z0, double z2, double z3) {
    	return Math.sqrt(((0.5 * (1.0 + Math.cos((z1 - z0)))) - ((-0.5 * (-1.0 + Math.cos(((z2 - z3) * 1.0)))) * ((Math.cos((z0 + z1)) + Math.cos((z0 - z1))) * 0.5))));
    }
    
    def code(z1, z0, z2, z3):
    	return math.sqrt(((0.5 * (1.0 + math.cos((z1 - z0)))) - ((-0.5 * (-1.0 + math.cos(((z2 - z3) * 1.0)))) * ((math.cos((z0 + z1)) + math.cos((z0 - z1))) * 0.5))))
    
    function code(z1, z0, z2, z3)
    	return sqrt(Float64(Float64(0.5 * Float64(1.0 + cos(Float64(z1 - z0)))) - Float64(Float64(-0.5 * Float64(-1.0 + cos(Float64(Float64(z2 - z3) * 1.0)))) * Float64(Float64(cos(Float64(z0 + z1)) + cos(Float64(z0 - z1))) * 0.5))))
    end
    
    function tmp = code(z1, z0, z2, z3)
    	tmp = sqrt(((0.5 * (1.0 + cos((z1 - z0)))) - ((-0.5 * (-1.0 + cos(((z2 - z3) * 1.0)))) * ((cos((z0 + z1)) + cos((z0 - z1))) * 0.5))));
    end
    
    code[z1_, z0_, z2_, z3_] := N[Sqrt[N[(N[(1/2 * N[(1 + N[Cos[N[(z1 - z0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(-1/2 * N[(-1 + N[Cos[N[(N[(z2 - z3), $MachinePrecision] * 1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(N[Cos[N[(z0 + z1), $MachinePrecision]], $MachinePrecision] + N[Cos[N[(z0 - z1), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * 1/2), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
    
    \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z0 + z1\right) + \cos \left(z0 - z1\right)\right) \cdot \frac{1}{2}\right)}
    
    Derivation
    1. Initial program 63.7%

      \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \color{blue}{\left(\cos z1 \cdot \cos z0\right)}} \]
      2. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\color{blue}{\cos z1} \cdot \cos z0\right)} \]
      3. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \color{blue}{\cos z0}\right)} \]
      4. cos-multN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \color{blue}{\frac{\cos \left(z1 + z0\right) + \cos \left(z1 - z0\right)}{2}}} \]
      5. mult-flipN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \color{blue}{\left(\left(\cos \left(z1 + z0\right) + \cos \left(z1 - z0\right)\right) \cdot \frac{1}{2}\right)}} \]
      6. metadata-evalN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z1 + z0\right) + \cos \left(z1 - z0\right)\right) \cdot \color{blue}{\frac{1}{2}}\right)} \]
      7. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \color{blue}{\left(\left(\cos \left(z1 + z0\right) + \cos \left(z1 - z0\right)\right) \cdot \frac{1}{2}\right)}} \]
      8. lift--.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z1 + z0\right) + \cos \color{blue}{\left(z1 - z0\right)}\right) \cdot \frac{1}{2}\right)} \]
      9. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z1 + z0\right) + \color{blue}{\cos \left(z1 - z0\right)}\right) \cdot \frac{1}{2}\right)} \]
      10. lower-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\color{blue}{\left(\cos \left(z1 + z0\right) + \cos \left(z1 - z0\right)\right)} \cdot \frac{1}{2}\right)} \]
      11. lower-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\color{blue}{\cos \left(z1 + z0\right)} + \cos \left(z1 - z0\right)\right) \cdot \frac{1}{2}\right)} \]
      12. +-commutativeN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \color{blue}{\left(z0 + z1\right)} + \cos \left(z1 - z0\right)\right) \cdot \frac{1}{2}\right)} \]
      13. lower-+.f6464.3%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \color{blue}{\left(z0 + z1\right)} + \cos \left(z1 - z0\right)\right) \cdot \frac{1}{2}\right)} \]
      14. lift-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z0 + z1\right) + \color{blue}{\cos \left(z1 - z0\right)}\right) \cdot \frac{1}{2}\right)} \]
      15. cos-neg-revN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z0 + z1\right) + \color{blue}{\cos \left(\mathsf{neg}\left(\left(z1 - z0\right)\right)\right)}\right) \cdot \frac{1}{2}\right)} \]
      16. lower-cos.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z0 + z1\right) + \color{blue}{\cos \left(\mathsf{neg}\left(\left(z1 - z0\right)\right)\right)}\right) \cdot \frac{1}{2}\right)} \]
      17. lift--.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z0 + z1\right) + \cos \left(\mathsf{neg}\left(\color{blue}{\left(z1 - z0\right)}\right)\right)\right) \cdot \frac{1}{2}\right)} \]
      18. sub-negate-revN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z0 + z1\right) + \cos \color{blue}{\left(z0 - z1\right)}\right) \cdot \frac{1}{2}\right)} \]
      19. lower--.f6464.3%

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\left(\cos \left(z0 + z1\right) + \cos \color{blue}{\left(z0 - z1\right)}\right) \cdot \frac{1}{2}\right)} \]
    3. Applied rewrites64.3%

      \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \color{blue}{\left(\left(\cos \left(z0 + z1\right) + \cos \left(z0 - z1\right)\right) \cdot \frac{1}{2}\right)}} \]
    4. Add Preprocessing

    Alternative 11: 64.2% accurate, 1.0× speedup?

    \[\sqrt{\left|\left(\cos \left(z0 - z1\right) - -1\right) \cdot \frac{1}{2} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right|} \]
    (FPCore (z1 z0 z2 z3)
      :precision binary64
      (sqrt
     (fabs
      (-
       (* (- (cos (- z0 z1)) -1) 1/2)
       (* (* (* (cos z0) (cos z1)) -1/2) (- (cos (- z3 z2)) 1))))))
    double code(double z1, double z0, double z2, double z3) {
    	return sqrt(fabs((((cos((z0 - z1)) - -1.0) * 0.5) - (((cos(z0) * cos(z1)) * -0.5) * (cos((z3 - z2)) - 1.0)))));
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(z1, z0, z2, z3)
    use fmin_fmax_functions
        real(8), intent (in) :: z1
        real(8), intent (in) :: z0
        real(8), intent (in) :: z2
        real(8), intent (in) :: z3
        code = sqrt(abs((((cos((z0 - z1)) - (-1.0d0)) * 0.5d0) - (((cos(z0) * cos(z1)) * (-0.5d0)) * (cos((z3 - z2)) - 1.0d0)))))
    end function
    
    public static double code(double z1, double z0, double z2, double z3) {
    	return Math.sqrt(Math.abs((((Math.cos((z0 - z1)) - -1.0) * 0.5) - (((Math.cos(z0) * Math.cos(z1)) * -0.5) * (Math.cos((z3 - z2)) - 1.0)))));
    }
    
    def code(z1, z0, z2, z3):
    	return math.sqrt(math.fabs((((math.cos((z0 - z1)) - -1.0) * 0.5) - (((math.cos(z0) * math.cos(z1)) * -0.5) * (math.cos((z3 - z2)) - 1.0)))))
    
    function code(z1, z0, z2, z3)
    	return sqrt(abs(Float64(Float64(Float64(cos(Float64(z0 - z1)) - -1.0) * 0.5) - Float64(Float64(Float64(cos(z0) * cos(z1)) * -0.5) * Float64(cos(Float64(z3 - z2)) - 1.0)))))
    end
    
    function tmp = code(z1, z0, z2, z3)
    	tmp = sqrt(abs((((cos((z0 - z1)) - -1.0) * 0.5) - (((cos(z0) * cos(z1)) * -0.5) * (cos((z3 - z2)) - 1.0)))));
    end
    
    code[z1_, z0_, z2_, z3_] := N[Sqrt[N[Abs[N[(N[(N[(N[Cos[N[(z0 - z1), $MachinePrecision]], $MachinePrecision] - -1), $MachinePrecision] * 1/2), $MachinePrecision] - N[(N[(N[(N[Cos[z0], $MachinePrecision] * N[Cos[z1], $MachinePrecision]), $MachinePrecision] * -1/2), $MachinePrecision] * N[(N[Cos[N[(z3 - z2), $MachinePrecision]], $MachinePrecision] - 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]
    
    \sqrt{\left|\left(\cos \left(z0 - z1\right) - -1\right) \cdot \frac{1}{2} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right|}
    
    Derivation
    1. Initial program 63.7%

      \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. Step-by-step derivation
      1. rem-square-sqrtN/A

        \[\leadsto \sqrt{\color{blue}{\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \cdot \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}}} \]
      2. lift-sqrt.f64N/A

        \[\leadsto \sqrt{\color{blue}{\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \cdot \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
      3. lift-sqrt.f64N/A

        \[\leadsto \sqrt{\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \cdot \color{blue}{\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}}} \]
      4. sqr-abs-revN/A

        \[\leadsto \sqrt{\color{blue}{\left|\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}\right| \cdot \left|\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}\right|}} \]
      5. mul-fabsN/A

        \[\leadsto \sqrt{\color{blue}{\left|\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \cdot \sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}\right|}} \]
    3. Applied rewrites64.2%

      \[\leadsto \sqrt{\color{blue}{\left|\left(\cos \left(z0 - z1\right) - -1\right) \cdot \frac{1}{2} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right|}} \]
    4. Add Preprocessing

    Alternative 12: 63.8% accurate, 1.0× speedup?

    \[\sqrt{\cos \left(z0 - z1\right) \cdot \frac{1}{2} - \left(\left(\left(\frac{-1}{2} \cdot \cos z0\right) \cdot \cos z1\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right) - \frac{1}{2}\right)} \]
    (FPCore (z1 z0 z2 z3)
      :precision binary64
      (sqrt
     (-
      (* (cos (- z0 z1)) 1/2)
      (- (* (* (* -1/2 (cos z0)) (cos z1)) (- (cos (- z3 z2)) 1)) 1/2))))
    double code(double z1, double z0, double z2, double z3) {
    	return sqrt(((cos((z0 - z1)) * 0.5) - ((((-0.5 * cos(z0)) * cos(z1)) * (cos((z3 - z2)) - 1.0)) - 0.5)));
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(z1, z0, z2, z3)
    use fmin_fmax_functions
        real(8), intent (in) :: z1
        real(8), intent (in) :: z0
        real(8), intent (in) :: z2
        real(8), intent (in) :: z3
        code = sqrt(((cos((z0 - z1)) * 0.5d0) - (((((-0.5d0) * cos(z0)) * cos(z1)) * (cos((z3 - z2)) - 1.0d0)) - 0.5d0)))
    end function
    
    public static double code(double z1, double z0, double z2, double z3) {
    	return Math.sqrt(((Math.cos((z0 - z1)) * 0.5) - ((((-0.5 * Math.cos(z0)) * Math.cos(z1)) * (Math.cos((z3 - z2)) - 1.0)) - 0.5)));
    }
    
    def code(z1, z0, z2, z3):
    	return math.sqrt(((math.cos((z0 - z1)) * 0.5) - ((((-0.5 * math.cos(z0)) * math.cos(z1)) * (math.cos((z3 - z2)) - 1.0)) - 0.5)))
    
    function code(z1, z0, z2, z3)
    	return sqrt(Float64(Float64(cos(Float64(z0 - z1)) * 0.5) - Float64(Float64(Float64(Float64(-0.5 * cos(z0)) * cos(z1)) * Float64(cos(Float64(z3 - z2)) - 1.0)) - 0.5)))
    end
    
    function tmp = code(z1, z0, z2, z3)
    	tmp = sqrt(((cos((z0 - z1)) * 0.5) - ((((-0.5 * cos(z0)) * cos(z1)) * (cos((z3 - z2)) - 1.0)) - 0.5)));
    end
    
    code[z1_, z0_, z2_, z3_] := N[Sqrt[N[(N[(N[Cos[N[(z0 - z1), $MachinePrecision]], $MachinePrecision] * 1/2), $MachinePrecision] - N[(N[(N[(N[(-1/2 * N[Cos[z0], $MachinePrecision]), $MachinePrecision] * N[Cos[z1], $MachinePrecision]), $MachinePrecision] * N[(N[Cos[N[(z3 - z2), $MachinePrecision]], $MachinePrecision] - 1), $MachinePrecision]), $MachinePrecision] - 1/2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
    
    \sqrt{\cos \left(z0 - z1\right) \cdot \frac{1}{2} - \left(\left(\left(\frac{-1}{2} \cdot \cos z0\right) \cdot \cos z1\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right) - \frac{1}{2}\right)}
    
    Derivation
    1. Initial program 63.7%

      \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
      2. lift-*.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      4. distribute-rgt-inN/A

        \[\leadsto \sqrt{\color{blue}{\left(1 \cdot \frac{1}{2} + \cos \left(z1 - z0\right) \cdot \frac{1}{2}\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      5. metadata-evalN/A

        \[\leadsto \sqrt{\left(\color{blue}{\frac{1}{2}} + \cos \left(z1 - z0\right) \cdot \frac{1}{2}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      6. associate--l+N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
      7. lower-+.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
      8. lower--.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} + \color{blue}{\left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
    3. Applied rewrites63.8%

      \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z0 - z1\right) \cdot \frac{1}{2} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)}} \]
    4. Applied rewrites63.7%

      \[\leadsto \sqrt{\color{blue}{\cos \left(z0 - z1\right) \cdot \frac{1}{2} - \left(\left(\left(\frac{-1}{2} \cdot \cos z0\right) \cdot \cos z1\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right) - \frac{1}{2}\right)}} \]
    5. Add Preprocessing

    Alternative 13: 63.7% accurate, 1.0× speedup?

    \[\sqrt{\frac{1}{2} + \left(\cos \left(z0 - z1\right) \cdot \frac{1}{2} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)} \]
    (FPCore (z1 z0 z2 z3)
      :precision binary64
      (sqrt
     (+
      1/2
      (-
       (* (cos (- z0 z1)) 1/2)
       (* (* (* (cos z0) (cos z1)) -1/2) (- (cos (- z3 z2)) 1))))))
    double code(double z1, double z0, double z2, double z3) {
    	return sqrt((0.5 + ((cos((z0 - z1)) * 0.5) - (((cos(z0) * cos(z1)) * -0.5) * (cos((z3 - z2)) - 1.0)))));
    }
    
    module fmin_fmax_functions
        implicit none
        private
        public fmax
        public fmin
    
        interface fmax
            module procedure fmax88
            module procedure fmax44
            module procedure fmax84
            module procedure fmax48
        end interface
        interface fmin
            module procedure fmin88
            module procedure fmin44
            module procedure fmin84
            module procedure fmin48
        end interface
    contains
        real(8) function fmax88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(4) function fmax44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, max(x, y), y /= y), x /= x)
        end function
        real(8) function fmax84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, max(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmax48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), max(dble(x), y), y /= y), x /= x)
        end function
        real(8) function fmin88(x, y) result (res)
            real(8), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(4) function fmin44(x, y) result (res)
            real(4), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(y, merge(x, min(x, y), y /= y), x /= x)
        end function
        real(8) function fmin84(x, y) result(res)
            real(8), intent (in) :: x
            real(4), intent (in) :: y
            res = merge(dble(y), merge(x, min(x, dble(y)), y /= y), x /= x)
        end function
        real(8) function fmin48(x, y) result(res)
            real(4), intent (in) :: x
            real(8), intent (in) :: y
            res = merge(y, merge(dble(x), min(dble(x), y), y /= y), x /= x)
        end function
    end module
    
    real(8) function code(z1, z0, z2, z3)
    use fmin_fmax_functions
        real(8), intent (in) :: z1
        real(8), intent (in) :: z0
        real(8), intent (in) :: z2
        real(8), intent (in) :: z3
        code = sqrt((0.5d0 + ((cos((z0 - z1)) * 0.5d0) - (((cos(z0) * cos(z1)) * (-0.5d0)) * (cos((z3 - z2)) - 1.0d0)))))
    end function
    
    public static double code(double z1, double z0, double z2, double z3) {
    	return Math.sqrt((0.5 + ((Math.cos((z0 - z1)) * 0.5) - (((Math.cos(z0) * Math.cos(z1)) * -0.5) * (Math.cos((z3 - z2)) - 1.0)))));
    }
    
    def code(z1, z0, z2, z3):
    	return math.sqrt((0.5 + ((math.cos((z0 - z1)) * 0.5) - (((math.cos(z0) * math.cos(z1)) * -0.5) * (math.cos((z3 - z2)) - 1.0)))))
    
    function code(z1, z0, z2, z3)
    	return sqrt(Float64(0.5 + Float64(Float64(cos(Float64(z0 - z1)) * 0.5) - Float64(Float64(Float64(cos(z0) * cos(z1)) * -0.5) * Float64(cos(Float64(z3 - z2)) - 1.0)))))
    end
    
    function tmp = code(z1, z0, z2, z3)
    	tmp = sqrt((0.5 + ((cos((z0 - z1)) * 0.5) - (((cos(z0) * cos(z1)) * -0.5) * (cos((z3 - z2)) - 1.0)))));
    end
    
    code[z1_, z0_, z2_, z3_] := N[Sqrt[N[(1/2 + N[(N[(N[Cos[N[(z0 - z1), $MachinePrecision]], $MachinePrecision] * 1/2), $MachinePrecision] - N[(N[(N[(N[Cos[z0], $MachinePrecision] * N[Cos[z1], $MachinePrecision]), $MachinePrecision] * -1/2), $MachinePrecision] * N[(N[Cos[N[(z3 - z2), $MachinePrecision]], $MachinePrecision] - 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
    
    \sqrt{\frac{1}{2} + \left(\cos \left(z0 - z1\right) \cdot \frac{1}{2} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)}
    
    Derivation
    1. Initial program 63.7%

      \[\sqrt{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
    2. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)}} \]
      2. lift-*.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} \cdot \left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      3. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \cos \left(z1 - z0\right)\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      4. distribute-rgt-inN/A

        \[\leadsto \sqrt{\color{blue}{\left(1 \cdot \frac{1}{2} + \cos \left(z1 - z0\right) \cdot \frac{1}{2}\right)} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      5. metadata-evalN/A

        \[\leadsto \sqrt{\left(\color{blue}{\frac{1}{2}} + \cos \left(z1 - z0\right) \cdot \frac{1}{2}\right) - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)} \]
      6. associate--l+N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
      7. lower-+.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
      8. lower--.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} + \color{blue}{\left(\cos \left(z1 - z0\right) \cdot \frac{1}{2} - \left(\frac{-1}{2} \cdot \left(-1 + \cos \left(\left(z2 - z3\right) \cdot 1\right)\right)\right) \cdot \left(\cos z1 \cdot \cos z0\right)\right)}} \]
    3. Applied rewrites63.8%

      \[\leadsto \sqrt{\color{blue}{\frac{1}{2} + \left(\cos \left(z0 - z1\right) \cdot \frac{1}{2} - \left(\left(\cos z0 \cdot \cos z1\right) \cdot \frac{-1}{2}\right) \cdot \left(\cos \left(z3 - z2\right) - 1\right)\right)}} \]
    4. Add Preprocessing

    Reproduce

    ?
    herbie shell --seed 2025277 -o generate:taylor -o generate:evaluate
    (FPCore (z1 z0 z2 z3)
      :name "(sqrt (- (* 1/2 (+ 1 (cos (- z1 z0)))) (* (* -1/2 (+ -1 (cos (* (- z2 z3) 1)))) (* (cos z1) (cos z0)))))"
      :precision binary64
      (sqrt (- (* 1/2 (+ 1 (cos (- z1 z0)))) (* (* -1/2 (+ -1 (cos (* (- z2 z3) 1)))) (* (cos z1) (cos z0))))))