Trigonometry B

Percentage Accurate: 99.5% → 99.5%
Time: 2.8s
Alternatives: 10
Speedup: N/A×

Specification

?
\[\begin{array}{l} \\ \begin{array}{l} t_0 := \tan x \cdot \tan x\\ \frac{1 - t\_0}{1 + t\_0} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (* (tan x) (tan x)))) (/ (- 1.0 t_0) (+ 1.0 t_0))))
double code(double x) {
	double t_0 = tan(x) * tan(x);
	return (1.0 - t_0) / (1.0 + t_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(x)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8) :: t_0
    t_0 = tan(x) * tan(x)
    code = (1.0d0 - t_0) / (1.0d0 + t_0)
end function
public static double code(double x) {
	double t_0 = Math.tan(x) * Math.tan(x);
	return (1.0 - t_0) / (1.0 + t_0);
}
def code(x):
	t_0 = math.tan(x) * math.tan(x)
	return (1.0 - t_0) / (1.0 + t_0)
function code(x)
	t_0 = Float64(tan(x) * tan(x))
	return Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0))
end
function tmp = code(x)
	t_0 = tan(x) * tan(x);
	tmp = (1.0 - t_0) / (1.0 + t_0);
end
code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \tan x \cdot \tan x\\
\frac{1 - t\_0}{1 + t\_0}
\end{array}
\end{array}

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 10 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: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \tan x \cdot \tan x\\ \frac{1 - t\_0}{1 + t\_0} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (* (tan x) (tan x)))) (/ (- 1.0 t_0) (+ 1.0 t_0))))
double code(double x) {
	double t_0 = tan(x) * tan(x);
	return (1.0 - t_0) / (1.0 + t_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(x)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8) :: t_0
    t_0 = tan(x) * tan(x)
    code = (1.0d0 - t_0) / (1.0d0 + t_0)
end function
public static double code(double x) {
	double t_0 = Math.tan(x) * Math.tan(x);
	return (1.0 - t_0) / (1.0 + t_0);
}
def code(x):
	t_0 = math.tan(x) * math.tan(x)
	return (1.0 - t_0) / (1.0 + t_0)
function code(x)
	t_0 = Float64(tan(x) * tan(x))
	return Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0))
end
function tmp = code(x)
	t_0 = tan(x) * tan(x);
	tmp = (1.0 - t_0) / (1.0 + t_0);
end
code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \tan x \cdot \tan x\\
\frac{1 - t\_0}{1 + t\_0}
\end{array}
\end{array}

Alternative 1: 99.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.5 \cdot \cos \left(2 \cdot x\right)\\ t_1 := \frac{0.5 - t\_0}{0.5 + t\_0}\\ \frac{1 - t\_1}{1 + t\_1} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (* 0.5 (cos (* 2.0 x)))) (t_1 (/ (- 0.5 t_0) (+ 0.5 t_0))))
   (/ (- 1.0 t_1) (+ 1.0 t_1))))
double code(double x) {
	double t_0 = 0.5 * cos((2.0 * x));
	double t_1 = (0.5 - t_0) / (0.5 + t_0);
	return (1.0 - t_1) / (1.0 + t_1);
}
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(x)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: t_1
    t_0 = 0.5d0 * cos((2.0d0 * x))
    t_1 = (0.5d0 - t_0) / (0.5d0 + t_0)
    code = (1.0d0 - t_1) / (1.0d0 + t_1)
end function
public static double code(double x) {
	double t_0 = 0.5 * Math.cos((2.0 * x));
	double t_1 = (0.5 - t_0) / (0.5 + t_0);
	return (1.0 - t_1) / (1.0 + t_1);
}
def code(x):
	t_0 = 0.5 * math.cos((2.0 * x))
	t_1 = (0.5 - t_0) / (0.5 + t_0)
	return (1.0 - t_1) / (1.0 + t_1)
function code(x)
	t_0 = Float64(0.5 * cos(Float64(2.0 * x)))
	t_1 = Float64(Float64(0.5 - t_0) / Float64(0.5 + t_0))
	return Float64(Float64(1.0 - t_1) / Float64(1.0 + t_1))
end
function tmp = code(x)
	t_0 = 0.5 * cos((2.0 * x));
	t_1 = (0.5 - t_0) / (0.5 + t_0);
	tmp = (1.0 - t_1) / (1.0 + t_1);
end
code[x_] := Block[{t$95$0 = N[(0.5 * N[Cos[N[(2.0 * x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(0.5 - t$95$0), $MachinePrecision] / N[(0.5 + t$95$0), $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 - t$95$1), $MachinePrecision] / N[(1.0 + t$95$1), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.5 \cdot \cos \left(2 \cdot x\right)\\
t_1 := \frac{0.5 - t\_0}{0.5 + t\_0}\\
\frac{1 - t\_1}{1 + t\_1}
\end{array}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}}{1 + \tan x \cdot \tan x} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}}{1 + \tan x \cdot \tan x} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    7. unpow2N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}}{1 + \tan x \cdot \tan x} \]
    8. unpow2N/A

      \[\leadsto \frac{1 - \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
    10. unpow2N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    11. sqr-sin-aN/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    12. lower--.f64N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    13. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    14. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    15. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    16. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    17. sqr-cos-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    18. lower-+.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    19. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    20. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    21. lower-*.f6498.9

      \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
  3. Applied rewrites98.9%

    \[\leadsto \frac{1 - \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x} \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
    7. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
    8. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
    10. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}} \]
    11. sqr-sin-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    12. lower--.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    13. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    14. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    15. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    16. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}} \]
    17. sqr-cos-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    18. lower-+.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    19. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    20. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}} \]
    21. lower-*.f6499.5

      \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}} \]
  5. Applied rewrites99.5%

    \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}} \]
  6. Add Preprocessing

Alternative 2: 99.5% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \left(x + x\right)\\ t_1 := \mathsf{fma}\left(t\_0, 0.5, 0.5\right)\\ \left(\frac{t\_0 \cdot 0.5 - 0.5}{t\_1} + 1\right) \cdot t\_1 \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (cos (+ x x))) (t_1 (fma t_0 0.5 0.5)))
   (* (+ (/ (- (* t_0 0.5) 0.5) t_1) 1.0) t_1)))
double code(double x) {
	double t_0 = cos((x + x));
	double t_1 = fma(t_0, 0.5, 0.5);
	return ((((t_0 * 0.5) - 0.5) / t_1) + 1.0) * t_1;
}
function code(x)
	t_0 = cos(Float64(x + x))
	t_1 = fma(t_0, 0.5, 0.5)
	return Float64(Float64(Float64(Float64(Float64(t_0 * 0.5) - 0.5) / t_1) + 1.0) * t_1)
end
code[x_] := Block[{t$95$0 = N[Cos[N[(x + x), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(t$95$0 * 0.5 + 0.5), $MachinePrecision]}, N[(N[(N[(N[(N[(t$95$0 * 0.5), $MachinePrecision] - 0.5), $MachinePrecision] / t$95$1), $MachinePrecision] + 1.0), $MachinePrecision] * t$95$1), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \cos \left(x + x\right)\\
t_1 := \mathsf{fma}\left(t\_0, 0.5, 0.5\right)\\
\left(\frac{t\_0 \cdot 0.5 - 0.5}{t\_1} + 1\right) \cdot t\_1
\end{array}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}}{1 + \tan x \cdot \tan x} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}}{1 + \tan x \cdot \tan x} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    7. unpow2N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}}{1 + \tan x \cdot \tan x} \]
    8. unpow2N/A

      \[\leadsto \frac{1 - \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
    10. unpow2N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    11. sqr-sin-aN/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    12. lower--.f64N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    13. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    14. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    15. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    16. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    17. sqr-cos-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    18. lower-+.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    19. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    20. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    21. lower-*.f6498.9

      \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
  3. Applied rewrites98.9%

    \[\leadsto \frac{1 - \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x} \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
    7. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
    8. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
    10. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}} \]
    11. sqr-sin-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    12. lower--.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    13. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    14. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    15. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    16. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}} \]
    17. sqr-cos-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    18. lower-+.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    19. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    20. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}} \]
    21. lower-*.f6499.5

      \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}} \]
  5. Applied rewrites99.5%

    \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}} \]
  6. Taylor expanded in x around inf

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{1}{2} \cdot \frac{\cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}\right) - \frac{1}{2} \cdot \frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{\left(1 + \frac{1}{2} \cdot \frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}\right) - \frac{1}{2} \cdot \frac{\cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
  7. Applied rewrites99.4%

    \[\leadsto \color{blue}{\frac{1 + \frac{\cos \left(x + x\right) \cdot 0.5 - 0.5}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}{\frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}} \]
  8. Taylor expanded in x around inf

    \[\leadsto \left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \cdot \color{blue}{\left(\left(1 + \frac{1}{2} \cdot \frac{\cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}\right) - \frac{1}{2} \cdot \frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}\right)} \]
  9. Applied rewrites99.4%

    \[\leadsto \left(\frac{\cos \left(x + x\right) \cdot 0.5 - 0.5}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)} + 1\right) \cdot \color{blue}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)} \]
  10. Add Preprocessing

Alternative 3: 99.4% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := {\tan x}^{2}\\ \frac{1 - t\_0}{t\_0 - -1} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (pow (tan x) 2.0))) (/ (- 1.0 t_0) (- t_0 -1.0))))
double code(double x) {
	double t_0 = pow(tan(x), 2.0);
	return (1.0 - t_0) / (t_0 - -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(x)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8) :: t_0
    t_0 = tan(x) ** 2.0d0
    code = (1.0d0 - t_0) / (t_0 - (-1.0d0))
end function
public static double code(double x) {
	double t_0 = Math.pow(Math.tan(x), 2.0);
	return (1.0 - t_0) / (t_0 - -1.0);
}
def code(x):
	t_0 = math.pow(math.tan(x), 2.0)
	return (1.0 - t_0) / (t_0 - -1.0)
function code(x)
	t_0 = tan(x) ^ 2.0
	return Float64(Float64(1.0 - t_0) / Float64(t_0 - -1.0))
end
function tmp = code(x)
	t_0 = tan(x) ^ 2.0;
	tmp = (1.0 - t_0) / (t_0 - -1.0);
end
code[x_] := Block[{t$95$0 = N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]}, N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(t$95$0 - -1.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := {\tan x}^{2}\\
\frac{1 - t\_0}{t\_0 - -1}
\end{array}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    3. lift-tan.f64N/A

      \[\leadsto \frac{1 - \tan x \cdot \color{blue}{\tan x}}{1 + \tan x \cdot \tan x} \]
    4. pow2N/A

      \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
    5. lower-pow.f64N/A

      \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1 + \tan x \cdot \tan x} \]
    6. lift-tan.f6499.5

      \[\leadsto \frac{1 - {\color{blue}{\tan x}}^{2}}{1 + \tan x \cdot \tan x} \]
    7. lift-+.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{1 + \tan x \cdot \tan x}} \]
    8. lift-*.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    9. lift-tan.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \color{blue}{\tan x} \cdot \tan x} \]
    10. lift-tan.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{1 + \tan x \cdot \color{blue}{\tan x}} \]
    11. +-commutativeN/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{\tan x \cdot \tan x + 1}} \]
    12. metadata-evalN/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{\tan x \cdot \tan x + \color{blue}{1 \cdot 1}} \]
    13. fp-cancel-sign-sub-invN/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{\tan x \cdot \tan x - \left(\mathsf{neg}\left(1\right)\right) \cdot 1}} \]
    14. metadata-evalN/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{\tan x \cdot \tan x - \color{blue}{-1} \cdot 1} \]
    15. metadata-evalN/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{\tan x \cdot \tan x - \color{blue}{-1}} \]
    16. lower--.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{\tan x \cdot \tan x - -1}} \]
    17. pow2N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{{\tan x}^{2}} - -1} \]
    18. lower-pow.f64N/A

      \[\leadsto \frac{1 - {\tan x}^{2}}{\color{blue}{{\tan x}^{2}} - -1} \]
    19. lift-tan.f6499.5

      \[\leadsto \frac{1 - {\tan x}^{2}}{{\color{blue}{\tan x}}^{2} - -1} \]
  3. Applied rewrites99.5%

    \[\leadsto \color{blue}{\frac{1 - {\tan x}^{2}}{{\tan x}^{2} - -1}} \]
  4. Add Preprocessing

Alternative 4: 98.9% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \left(1 - {\tan x}^{2}\right) \cdot \mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (* (- 1.0 (pow (tan x) 2.0)) (fma (cos (+ x x)) 0.5 0.5)))
double code(double x) {
	return (1.0 - pow(tan(x), 2.0)) * fma(cos((x + x)), 0.5, 0.5);
}
function code(x)
	return Float64(Float64(1.0 - (tan(x) ^ 2.0)) * fma(cos(Float64(x + x)), 0.5, 0.5))
end
code[x_] := N[(N[(1.0 - N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] * N[(N[Cos[N[(x + x), $MachinePrecision]], $MachinePrecision] * 0.5 + 0.5), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(1 - {\tan x}^{2}\right) \cdot \mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}}{1 + \tan x \cdot \tan x} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}}{1 + \tan x \cdot \tan x} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    7. unpow2N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}}{1 + \tan x \cdot \tan x} \]
    8. unpow2N/A

      \[\leadsto \frac{1 - \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
    10. unpow2N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    11. sqr-sin-aN/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    12. lower--.f64N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    13. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    14. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    15. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    16. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    17. sqr-cos-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    18. lower-+.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    19. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    20. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    21. lower-*.f6498.9

      \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
  3. Applied rewrites98.9%

    \[\leadsto \frac{1 - \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x} \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
    7. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
    8. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
    10. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}} \]
    11. sqr-sin-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    12. lower--.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    13. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    14. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    15. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    16. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}} \]
    17. sqr-cos-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    18. lower-+.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    19. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    20. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}} \]
    21. lower-*.f6499.5

      \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}} \]
  5. Applied rewrites99.5%

    \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}} \]
  6. Applied rewrites98.8%

    \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{1 - \tan x}{\frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}} \]
  7. Taylor expanded in x around inf

    \[\leadsto \color{blue}{\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \cdot \left(\left(1 + \frac{\sin x}{\cos x}\right) \cdot \left(1 - \frac{\sin x}{\cos x}\right)\right)} \]
  8. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \left(\left(1 + \frac{\sin x}{\cos x}\right) \cdot \left(1 - \frac{\sin x}{\cos x}\right)\right) \cdot \color{blue}{\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right)} \]
    2. tan-quotN/A

      \[\leadsto \left(\left(1 + \tan x\right) \cdot \left(1 - \frac{\sin x}{\cos x}\right)\right) \cdot \left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \]
    3. tan-quotN/A

      \[\leadsto \left(\left(1 + \tan x\right) \cdot \left(1 - \tan x\right)\right) \cdot \left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \]
    4. difference-of-squares-revN/A

      \[\leadsto \left(1 \cdot 1 - \tan x \cdot \tan x\right) \cdot \left(\color{blue}{\frac{1}{2}} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \]
    5. metadata-evalN/A

      \[\leadsto \left(1 - \tan x \cdot \tan x\right) \cdot \left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \]
    6. pow2N/A

      \[\leadsto \left(1 - {\tan x}^{2}\right) \cdot \left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \]
    7. lower-*.f64N/A

      \[\leadsto \left(1 - {\tan x}^{2}\right) \cdot \color{blue}{\left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right)} \]
    8. lift-tan.f64N/A

      \[\leadsto \left(1 - {\tan x}^{2}\right) \cdot \left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \]
    9. lift-pow.f64N/A

      \[\leadsto \left(1 - {\tan x}^{2}\right) \cdot \left(\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \]
    10. lift--.f64N/A

      \[\leadsto \left(1 - {\tan x}^{2}\right) \cdot \left(\color{blue}{\frac{1}{2}} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)\right) \]
    11. +-commutativeN/A

      \[\leadsto \left(1 - {\tan x}^{2}\right) \cdot \left(\frac{1}{2} \cdot \cos \left(2 \cdot x\right) + \color{blue}{\frac{1}{2}}\right) \]
    12. *-commutativeN/A

      \[\leadsto \left(1 - {\tan x}^{2}\right) \cdot \left(\cos \left(2 \cdot x\right) \cdot \frac{1}{2} + \frac{1}{2}\right) \]
  9. Applied rewrites98.9%

    \[\leadsto \color{blue}{\left(1 - {\tan x}^{2}\right) \cdot \mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)} \]
  10. Add Preprocessing

Alternative 5: 59.0% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \cos \left(x + x\right)\\ \frac{1 + \frac{t\_0 \cdot 0.5 - 0.5}{\mathsf{fma}\left(t\_0, 0.5, 0.5\right)}}{1} \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (cos (+ x x))))
   (/ (+ 1.0 (/ (- (* t_0 0.5) 0.5) (fma t_0 0.5 0.5))) 1.0)))
double code(double x) {
	double t_0 = cos((x + x));
	return (1.0 + (((t_0 * 0.5) - 0.5) / fma(t_0, 0.5, 0.5))) / 1.0;
}
function code(x)
	t_0 = cos(Float64(x + x))
	return Float64(Float64(1.0 + Float64(Float64(Float64(t_0 * 0.5) - 0.5) / fma(t_0, 0.5, 0.5))) / 1.0)
end
code[x_] := Block[{t$95$0 = N[Cos[N[(x + x), $MachinePrecision]], $MachinePrecision]}, N[(N[(1.0 + N[(N[(N[(t$95$0 * 0.5), $MachinePrecision] - 0.5), $MachinePrecision] / N[(t$95$0 * 0.5 + 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / 1.0), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \cos \left(x + x\right)\\
\frac{1 + \frac{t\_0 \cdot 0.5 - 0.5}{\mathsf{fma}\left(t\_0, 0.5, 0.5\right)}}{1}
\end{array}
\end{array}
Derivation
  1. Initial program 99.5%

    \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
  2. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}}{1 + \tan x \cdot \tan x} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}}{1 + \tan x \cdot \tan x} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    7. unpow2N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}}{1 + \tan x \cdot \tan x} \]
    8. unpow2N/A

      \[\leadsto \frac{1 - \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{1 - \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
    10. unpow2N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    11. sqr-sin-aN/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    12. lower--.f64N/A

      \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    13. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    14. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    15. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
    16. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
    17. sqr-cos-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    18. lower-+.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    19. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    20. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
    21. lower-*.f6498.9

      \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
  3. Applied rewrites98.9%

    \[\leadsto \frac{1 - \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
  4. Step-by-step derivation
    1. lift-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
    2. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x} \cdot \tan x} \]
    3. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}} \]
    5. tan-quotN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
    6. frac-timesN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
    7. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
    8. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
    10. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}} \]
    11. sqr-sin-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    12. lower--.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    13. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    14. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    15. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
    16. unpow2N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}} \]
    17. sqr-cos-aN/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    18. lower-+.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    19. lower-*.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
    20. lower-cos.f64N/A

      \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}} \]
    21. lower-*.f6499.5

      \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}} \]
  5. Applied rewrites99.5%

    \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}} \]
  6. Taylor expanded in x around inf

    \[\leadsto \color{blue}{\frac{\left(1 + \frac{1}{2} \cdot \frac{\cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}\right) - \frac{1}{2} \cdot \frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{\left(1 + \frac{1}{2} \cdot \frac{1}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}\right) - \frac{1}{2} \cdot \frac{\cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
  7. Applied rewrites99.4%

    \[\leadsto \color{blue}{\frac{1 + \frac{\cos \left(x + x\right) \cdot 0.5 - 0.5}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}{\frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}} \]
  8. Taylor expanded in x around 0

    \[\leadsto \frac{1 + \frac{\cos \left(x + x\right) \cdot \frac{1}{2} - \frac{1}{2}}{\mathsf{fma}\left(\cos \left(x + x\right), \frac{1}{2}, \frac{1}{2}\right)}}{1} \]
  9. Step-by-step derivation
    1. Applied rewrites59.0%

      \[\leadsto \frac{1 + \frac{\cos \left(x + x\right) \cdot 0.5 - 0.5}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}{1} \]
    2. Add Preprocessing

    Alternative 6: 59.0% accurate, 1.8× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \tan \left(x + \pi\right)\\ \frac{1 - t\_0 \cdot t\_0}{1} \end{array} \end{array} \]
    (FPCore (x)
     :precision binary64
     (let* ((t_0 (tan (+ x PI)))) (/ (- 1.0 (* t_0 t_0)) 1.0)))
    double code(double x) {
    	double t_0 = tan((x + ((double) M_PI)));
    	return (1.0 - (t_0 * t_0)) / 1.0;
    }
    
    public static double code(double x) {
    	double t_0 = Math.tan((x + Math.PI));
    	return (1.0 - (t_0 * t_0)) / 1.0;
    }
    
    def code(x):
    	t_0 = math.tan((x + math.pi))
    	return (1.0 - (t_0 * t_0)) / 1.0
    
    function code(x)
    	t_0 = tan(Float64(x + pi))
    	return Float64(Float64(1.0 - Float64(t_0 * t_0)) / 1.0)
    end
    
    function tmp = code(x)
    	t_0 = tan((x + pi));
    	tmp = (1.0 - (t_0 * t_0)) / 1.0;
    end
    
    code[x_] := Block[{t$95$0 = N[Tan[N[(x + Pi), $MachinePrecision]], $MachinePrecision]}, N[(N[(1.0 - N[(t$95$0 * t$95$0), $MachinePrecision]), $MachinePrecision] / 1.0), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := \tan \left(x + \pi\right)\\
    \frac{1 - t\_0 \cdot t\_0}{1}
    \end{array}
    \end{array}
    
    Derivation
    1. Initial program 99.5%

      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
    2. Taylor expanded in x around 0

      \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{1}} \]
    3. Step-by-step derivation
      1. Applied rewrites59.0%

        \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{1}} \]
      2. Step-by-step derivation
        1. lift-tan.f64N/A

          \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1} \]
        2. tan-+PI-revN/A

          \[\leadsto \frac{1 - \color{blue}{\tan \left(x + \mathsf{PI}\left(\right)\right)} \cdot \tan x}{1} \]
        3. lower-tan.f64N/A

          \[\leadsto \frac{1 - \color{blue}{\tan \left(x + \mathsf{PI}\left(\right)\right)} \cdot \tan x}{1} \]
        4. lower-+.f64N/A

          \[\leadsto \frac{1 - \tan \color{blue}{\left(x + \mathsf{PI}\left(\right)\right)} \cdot \tan x}{1} \]
        5. lower-PI.f6459.0

          \[\leadsto \frac{1 - \tan \left(x + \color{blue}{\pi}\right) \cdot \tan x}{1} \]
      3. Applied rewrites59.0%

        \[\leadsto \frac{1 - \color{blue}{\tan \left(x + \pi\right)} \cdot \tan x}{1} \]
      4. Step-by-step derivation
        1. lift-tan.f64N/A

          \[\leadsto \frac{1 - \tan \left(x + \pi\right) \cdot \color{blue}{\tan x}}{1} \]
        2. tan-+PI-revN/A

          \[\leadsto \frac{1 - \tan \left(x + \pi\right) \cdot \color{blue}{\tan \left(x + \mathsf{PI}\left(\right)\right)}}{1} \]
        3. lower-tan.f64N/A

          \[\leadsto \frac{1 - \tan \left(x + \pi\right) \cdot \color{blue}{\tan \left(x + \mathsf{PI}\left(\right)\right)}}{1} \]
        4. lower-+.f64N/A

          \[\leadsto \frac{1 - \tan \left(x + \pi\right) \cdot \tan \color{blue}{\left(x + \mathsf{PI}\left(\right)\right)}}{1} \]
        5. lower-PI.f6459.0

          \[\leadsto \frac{1 - \tan \left(x + \pi\right) \cdot \tan \left(x + \color{blue}{\pi}\right)}{1} \]
      5. Applied rewrites59.0%

        \[\leadsto \frac{1 - \tan \left(x + \pi\right) \cdot \color{blue}{\tan \left(x + \pi\right)}}{1} \]
      6. Add Preprocessing

      Alternative 7: 59.0% accurate, 2.7× speedup?

      \[\begin{array}{l} \\ \frac{1 - {\tan x}^{2}}{1} \end{array} \]
      (FPCore (x) :precision binary64 (/ (- 1.0 (pow (tan x) 2.0)) 1.0))
      double code(double x) {
      	return (1.0 - pow(tan(x), 2.0)) / 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(x)
      use fmin_fmax_functions
          real(8), intent (in) :: x
          code = (1.0d0 - (tan(x) ** 2.0d0)) / 1.0d0
      end function
      
      public static double code(double x) {
      	return (1.0 - Math.pow(Math.tan(x), 2.0)) / 1.0;
      }
      
      def code(x):
      	return (1.0 - math.pow(math.tan(x), 2.0)) / 1.0
      
      function code(x)
      	return Float64(Float64(1.0 - (tan(x) ^ 2.0)) / 1.0)
      end
      
      function tmp = code(x)
      	tmp = (1.0 - (tan(x) ^ 2.0)) / 1.0;
      end
      
      code[x_] := N[(N[(1.0 - N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision] / 1.0), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{1 - {\tan x}^{2}}{1}
      \end{array}
      
      Derivation
      1. Initial program 99.5%

        \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
      2. Taylor expanded in x around 0

        \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{1}} \]
      3. Step-by-step derivation
        1. Applied rewrites59.0%

          \[\leadsto \frac{1 - \tan x \cdot \tan x}{\color{blue}{1}} \]
        2. Step-by-step derivation
          1. lift-*.f64N/A

            \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1} \]
          2. lift-tan.f64N/A

            \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1} \]
          3. lift-tan.f64N/A

            \[\leadsto \frac{1 - \tan x \cdot \color{blue}{\tan x}}{1} \]
          4. pow2N/A

            \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1} \]
          5. lower-pow.f64N/A

            \[\leadsto \frac{1 - \color{blue}{{\tan x}^{2}}}{1} \]
          6. lift-tan.f6459.0

            \[\leadsto \frac{1 - {\color{blue}{\tan x}}^{2}}{1} \]
        3. Applied rewrites59.0%

          \[\leadsto \color{blue}{\frac{1 - {\tan x}^{2}}{1}} \]
        4. Add Preprocessing

        Alternative 8: 57.1% accurate, 3.4× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.92:\\ \;\;\;\;\mathsf{fma}\left(\left(\left(\mathsf{fma}\left(-0.08888888888888889, x \cdot x, 0.6666666666666666\right) \cdot x\right) \cdot x - 2\right) \cdot x, x, 1\right)\\ \mathbf{else}:\\ \;\;\;\;\left(\tan x + 1\right) \cdot 1\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x 1.92)
           (fma
            (*
             (- (* (* (fma -0.08888888888888889 (* x x) 0.6666666666666666) x) x) 2.0)
             x)
            x
            1.0)
           (* (+ (tan x) 1.0) 1.0)))
        double code(double x) {
        	double tmp;
        	if (x <= 1.92) {
        		tmp = fma(((((fma(-0.08888888888888889, (x * x), 0.6666666666666666) * x) * x) - 2.0) * x), x, 1.0);
        	} else {
        		tmp = (tan(x) + 1.0) * 1.0;
        	}
        	return tmp;
        }
        
        function code(x)
        	tmp = 0.0
        	if (x <= 1.92)
        		tmp = fma(Float64(Float64(Float64(Float64(fma(-0.08888888888888889, Float64(x * x), 0.6666666666666666) * x) * x) - 2.0) * x), x, 1.0);
        	else
        		tmp = Float64(Float64(tan(x) + 1.0) * 1.0);
        	end
        	return tmp
        end
        
        code[x_] := If[LessEqual[x, 1.92], N[(N[(N[(N[(N[(N[(-0.08888888888888889 * N[(x * x), $MachinePrecision] + 0.6666666666666666), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] - 2.0), $MachinePrecision] * x), $MachinePrecision] * x + 1.0), $MachinePrecision], N[(N[(N[Tan[x], $MachinePrecision] + 1.0), $MachinePrecision] * 1.0), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq 1.92:\\
        \;\;\;\;\mathsf{fma}\left(\left(\left(\mathsf{fma}\left(-0.08888888888888889, x \cdot x, 0.6666666666666666\right) \cdot x\right) \cdot x - 2\right) \cdot x, x, 1\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\left(\tan x + 1\right) \cdot 1\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 1.9199999999999999

          1. Initial program 99.6%

            \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
          2. Taylor expanded in x around 0

            \[\leadsto \color{blue}{1 + {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{2}{3} + \frac{-4}{45} \cdot {x}^{2}\right) - 2\right)} \]
          3. Step-by-step derivation
            1. +-commutativeN/A

              \[\leadsto {x}^{2} \cdot \left({x}^{2} \cdot \left(\frac{2}{3} + \frac{-4}{45} \cdot {x}^{2}\right) - 2\right) + \color{blue}{1} \]
            2. *-commutativeN/A

              \[\leadsto \left({x}^{2} \cdot \left(\frac{2}{3} + \frac{-4}{45} \cdot {x}^{2}\right) - 2\right) \cdot {x}^{2} + 1 \]
            3. unpow2N/A

              \[\leadsto \left({x}^{2} \cdot \left(\frac{2}{3} + \frac{-4}{45} \cdot {x}^{2}\right) - 2\right) \cdot \left(x \cdot x\right) + 1 \]
            4. associate-*r*N/A

              \[\leadsto \left(\left({x}^{2} \cdot \left(\frac{2}{3} + \frac{-4}{45} \cdot {x}^{2}\right) - 2\right) \cdot x\right) \cdot x + 1 \]
            5. lower-fma.f64N/A

              \[\leadsto \mathsf{fma}\left(\left({x}^{2} \cdot \left(\frac{2}{3} + \frac{-4}{45} \cdot {x}^{2}\right) - 2\right) \cdot x, \color{blue}{x}, 1\right) \]
          4. Applied rewrites66.8%

            \[\leadsto \color{blue}{\mathsf{fma}\left(\left(\left(\mathsf{fma}\left(-0.08888888888888889, x \cdot x, 0.6666666666666666\right) \cdot x\right) \cdot x - 2\right) \cdot x, x, 1\right)} \]

          if 1.9199999999999999 < x

          1. Initial program 99.0%

            \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
          2. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \frac{1 - \color{blue}{\tan x \cdot \tan x}}{1 + \tan x \cdot \tan x} \]
            2. lift-tan.f64N/A

              \[\leadsto \frac{1 - \color{blue}{\tan x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
            3. tan-quotN/A

              \[\leadsto \frac{1 - \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
            4. lift-tan.f64N/A

              \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}}{1 + \tan x \cdot \tan x} \]
            5. tan-quotN/A

              \[\leadsto \frac{1 - \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}}{1 + \tan x \cdot \tan x} \]
            6. frac-timesN/A

              \[\leadsto \frac{1 - \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
            7. unpow2N/A

              \[\leadsto \frac{1 - \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}}{1 + \tan x \cdot \tan x} \]
            8. unpow2N/A

              \[\leadsto \frac{1 - \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
            9. lower-/.f64N/A

              \[\leadsto \frac{1 - \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}}{1 + \tan x \cdot \tan x} \]
            10. unpow2N/A

              \[\leadsto \frac{1 - \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
            11. sqr-sin-aN/A

              \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
            12. lower--.f64N/A

              \[\leadsto \frac{1 - \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
            13. lower-*.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
            14. lower-cos.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
            15. lower-*.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}}{1 + \tan x \cdot \tan x} \]
            16. unpow2N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}}{1 + \tan x \cdot \tan x} \]
            17. sqr-cos-aN/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
            18. lower-+.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
            19. lower-*.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
            20. lower-cos.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
            21. lower-*.f6497.7

              \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
          3. Applied rewrites97.7%

            \[\leadsto \frac{1 - \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}}{1 + \tan x \cdot \tan x} \]
          4. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x \cdot \tan x}} \]
            2. lift-tan.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\tan x} \cdot \tan x} \]
            3. tan-quotN/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x}{\cos x}} \cdot \tan x} \]
            4. lift-tan.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\tan x}} \]
            5. tan-quotN/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\sin x}{\cos x} \cdot \color{blue}{\frac{\sin x}{\cos x}}} \]
            6. frac-timesN/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{\sin x \cdot \sin x}{\cos x \cdot \cos x}}} \]
            7. unpow2N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{{\sin x}^{2}}}{\cos x \cdot \cos x}} \]
            8. unpow2N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}} \]
            9. lower-/.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}} \]
            10. unpow2N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\sin x \cdot \sin x}}{{\cos x}^{2}}} \]
            11. sqr-sin-aN/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
            12. lower--.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\color{blue}{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
            13. lower-*.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
            14. lower-cos.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
            15. lower-*.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \color{blue}{\left(2 \cdot x\right)}}{{\cos x}^{2}}} \]
            16. unpow2N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\cos x \cdot \cos x}}} \]
            17. sqr-cos-aN/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
            18. lower-+.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\color{blue}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
            19. lower-*.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \color{blue}{\frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}} \]
            20. lower-cos.f64N/A

              \[\leadsto \frac{1 - \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{\frac{1}{2} - \frac{1}{2} \cdot \cos \left(2 \cdot x\right)}{\frac{1}{2} + \frac{1}{2} \cdot \color{blue}{\cos \left(2 \cdot x\right)}}} \]
            21. lower-*.f6498.9

              \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \color{blue}{\left(2 \cdot x\right)}}} \]
          5. Applied rewrites98.9%

            \[\leadsto \frac{1 - \frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}{1 + \color{blue}{\frac{0.5 - 0.5 \cdot \cos \left(2 \cdot x\right)}{0.5 + 0.5 \cdot \cos \left(2 \cdot x\right)}}} \]
          6. Applied rewrites97.5%

            \[\leadsto \color{blue}{\left(\tan x + 1\right) \cdot \frac{1 - \tan x}{\frac{1}{\mathsf{fma}\left(\cos \left(x + x\right), 0.5, 0.5\right)}}} \]
          7. Taylor expanded in x around 0

            \[\leadsto \left(\tan x + 1\right) \cdot \color{blue}{1} \]
          8. Step-by-step derivation
            1. Applied rewrites15.9%

              \[\leadsto \left(\tan x + 1\right) \cdot \color{blue}{1} \]
          9. Recombined 2 regimes into one program.
          10. Add Preprocessing

          Alternative 9: 54.7% accurate, 0.9× speedup?

          \[\begin{array}{l} \\ \begin{array}{l} t_0 := \tan x \cdot \tan x\\ \mathbf{if}\;\frac{1 - t\_0}{1 + t\_0} \leq -0.0001:\\ \;\;\;\;\frac{1 - x \cdot x}{1 + x \cdot x}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
          (FPCore (x)
           :precision binary64
           (let* ((t_0 (* (tan x) (tan x))))
             (if (<= (/ (- 1.0 t_0) (+ 1.0 t_0)) -0.0001)
               (/ (- 1.0 (* x x)) (+ 1.0 (* x x)))
               1.0)))
          double code(double x) {
          	double t_0 = tan(x) * tan(x);
          	double tmp;
          	if (((1.0 - t_0) / (1.0 + t_0)) <= -0.0001) {
          		tmp = (1.0 - (x * x)) / (1.0 + (x * x));
          	} else {
          		tmp = 1.0;
          	}
          	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(x)
          use fmin_fmax_functions
              real(8), intent (in) :: x
              real(8) :: t_0
              real(8) :: tmp
              t_0 = tan(x) * tan(x)
              if (((1.0d0 - t_0) / (1.0d0 + t_0)) <= (-0.0001d0)) then
                  tmp = (1.0d0 - (x * x)) / (1.0d0 + (x * x))
              else
                  tmp = 1.0d0
              end if
              code = tmp
          end function
          
          public static double code(double x) {
          	double t_0 = Math.tan(x) * Math.tan(x);
          	double tmp;
          	if (((1.0 - t_0) / (1.0 + t_0)) <= -0.0001) {
          		tmp = (1.0 - (x * x)) / (1.0 + (x * x));
          	} else {
          		tmp = 1.0;
          	}
          	return tmp;
          }
          
          def code(x):
          	t_0 = math.tan(x) * math.tan(x)
          	tmp = 0
          	if ((1.0 - t_0) / (1.0 + t_0)) <= -0.0001:
          		tmp = (1.0 - (x * x)) / (1.0 + (x * x))
          	else:
          		tmp = 1.0
          	return tmp
          
          function code(x)
          	t_0 = Float64(tan(x) * tan(x))
          	tmp = 0.0
          	if (Float64(Float64(1.0 - t_0) / Float64(1.0 + t_0)) <= -0.0001)
          		tmp = Float64(Float64(1.0 - Float64(x * x)) / Float64(1.0 + Float64(x * x)));
          	else
          		tmp = 1.0;
          	end
          	return tmp
          end
          
          function tmp_2 = code(x)
          	t_0 = tan(x) * tan(x);
          	tmp = 0.0;
          	if (((1.0 - t_0) / (1.0 + t_0)) <= -0.0001)
          		tmp = (1.0 - (x * x)) / (1.0 + (x * x));
          	else
          		tmp = 1.0;
          	end
          	tmp_2 = tmp;
          end
          
          code[x_] := Block[{t$95$0 = N[(N[Tan[x], $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[N[(N[(1.0 - t$95$0), $MachinePrecision] / N[(1.0 + t$95$0), $MachinePrecision]), $MachinePrecision], -0.0001], N[(N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision] / N[(1.0 + N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.0]]
          
          \begin{array}{l}
          
          \\
          \begin{array}{l}
          t_0 := \tan x \cdot \tan x\\
          \mathbf{if}\;\frac{1 - t\_0}{1 + t\_0} \leq -0.0001:\\
          \;\;\;\;\frac{1 - x \cdot x}{1 + x \cdot x}\\
          
          \mathbf{else}:\\
          \;\;\;\;1\\
          
          
          \end{array}
          \end{array}
          
          Derivation
          1. Split input into 2 regimes
          2. if (/.f64 (-.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))) (+.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x)))) < -1.00000000000000005e-4

            1. Initial program 99.1%

              \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
            2. Taylor expanded in x around 0

              \[\leadsto \frac{1 - \color{blue}{x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
            3. Step-by-step derivation
              1. Applied rewrites3.3%

                \[\leadsto \frac{1 - \color{blue}{x} \cdot \tan x}{1 + \tan x \cdot \tan x} \]
              2. Taylor expanded in x around 0

                \[\leadsto \frac{1 - x \cdot \color{blue}{x}}{1 + \tan x \cdot \tan x} \]
              3. Step-by-step derivation
                1. Applied rewrites4.4%

                  \[\leadsto \frac{1 - x \cdot \color{blue}{x}}{1 + \tan x \cdot \tan x} \]
                2. Taylor expanded in x around 0

                  \[\leadsto \frac{1 - x \cdot x}{1 + \color{blue}{x} \cdot \tan x} \]
                3. Step-by-step derivation
                  1. Applied rewrites3.0%

                    \[\leadsto \frac{1 - x \cdot x}{1 + \color{blue}{x} \cdot \tan x} \]
                  2. Taylor expanded in x around 0

                    \[\leadsto \frac{1 - x \cdot x}{1 + x \cdot \color{blue}{x}} \]
                  3. Step-by-step derivation
                    1. Applied rewrites11.0%

                      \[\leadsto \frac{1 - x \cdot x}{1 + x \cdot \color{blue}{x}} \]

                    if -1.00000000000000005e-4 < (/.f64 (-.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))) (+.f64 #s(literal 1 binary64) (*.f64 (tan.f64 x) (tan.f64 x))))

                    1. Initial program 99.6%

                      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
                    2. Taylor expanded in x around 0

                      \[\leadsto \color{blue}{1} \]
                    3. Step-by-step derivation
                      1. Applied rewrites72.6%

                        \[\leadsto \color{blue}{1} \]
                    4. Recombined 2 regimes into one program.
                    5. Add Preprocessing

                    Alternative 10: 54.0% accurate, 155.8× speedup?

                    \[\begin{array}{l} \\ 1 \end{array} \]
                    (FPCore (x) :precision binary64 1.0)
                    double code(double x) {
                    	return 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(x)
                    use fmin_fmax_functions
                        real(8), intent (in) :: x
                        code = 1.0d0
                    end function
                    
                    public static double code(double x) {
                    	return 1.0;
                    }
                    
                    def code(x):
                    	return 1.0
                    
                    function code(x)
                    	return 1.0
                    end
                    
                    function tmp = code(x)
                    	tmp = 1.0;
                    end
                    
                    code[x_] := 1.0
                    
                    \begin{array}{l}
                    
                    \\
                    1
                    \end{array}
                    
                    Derivation
                    1. Initial program 99.5%

                      \[\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x} \]
                    2. Taylor expanded in x around 0

                      \[\leadsto \color{blue}{1} \]
                    3. Step-by-step derivation
                      1. Applied rewrites54.7%

                        \[\leadsto \color{blue}{1} \]
                      2. Add Preprocessing

                      Reproduce

                      ?
                      herbie shell --seed 2025116 
                      (FPCore (x)
                        :name "Trigonometry B"
                        :precision binary64
                        (/ (- 1.0 (* (tan x) (tan x))) (+ 1.0 (* (tan x) (tan x)))))