Toniolo and Linder, Equation (3a)

Percentage Accurate: 98.4% → 98.5%
Time: 9.6s
Alternatives: 5
Speedup: 1.1×

Specification

?
\[\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)} \]
(FPCore (l Om kx ky)
 :precision binary64
 (sqrt
  (*
   (/ 1.0 2.0)
   (+
    1.0
    (/
     1.0
     (sqrt
      (+
       1.0
       (*
        (pow (/ (* 2.0 l) Om) 2.0)
        (+ (pow (sin kx) 2.0) (pow (sin ky) 2.0))))))))))
double code(double l, double Om, double kx, double ky) {
	return sqrt(((1.0 / 2.0) * (1.0 + (1.0 / sqrt((1.0 + (pow(((2.0 * l) / Om), 2.0) * (pow(sin(kx), 2.0) + pow(sin(ky), 2.0)))))))));
}
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(l, om, kx, ky)
use fmin_fmax_functions
    real(8), intent (in) :: l
    real(8), intent (in) :: om
    real(8), intent (in) :: kx
    real(8), intent (in) :: ky
    code = sqrt(((1.0d0 / 2.0d0) * (1.0d0 + (1.0d0 / sqrt((1.0d0 + ((((2.0d0 * l) / om) ** 2.0d0) * ((sin(kx) ** 2.0d0) + (sin(ky) ** 2.0d0)))))))))
end function
public static double code(double l, double Om, double kx, double ky) {
	return Math.sqrt(((1.0 / 2.0) * (1.0 + (1.0 / Math.sqrt((1.0 + (Math.pow(((2.0 * l) / Om), 2.0) * (Math.pow(Math.sin(kx), 2.0) + Math.pow(Math.sin(ky), 2.0)))))))));
}
def code(l, Om, kx, ky):
	return math.sqrt(((1.0 / 2.0) * (1.0 + (1.0 / math.sqrt((1.0 + (math.pow(((2.0 * l) / Om), 2.0) * (math.pow(math.sin(kx), 2.0) + math.pow(math.sin(ky), 2.0)))))))))
function code(l, Om, kx, ky)
	return sqrt(Float64(Float64(1.0 / 2.0) * Float64(1.0 + Float64(1.0 / sqrt(Float64(1.0 + Float64((Float64(Float64(2.0 * l) / Om) ^ 2.0) * Float64((sin(kx) ^ 2.0) + (sin(ky) ^ 2.0)))))))))
end
function tmp = code(l, Om, kx, ky)
	tmp = sqrt(((1.0 / 2.0) * (1.0 + (1.0 / sqrt((1.0 + ((((2.0 * l) / Om) ^ 2.0) * ((sin(kx) ^ 2.0) + (sin(ky) ^ 2.0)))))))));
end
code[l_, Om_, kx_, ky_] := N[Sqrt[N[(N[(1.0 / 2.0), $MachinePrecision] * N[(1.0 + N[(1.0 / N[Sqrt[N[(1.0 + N[(N[Power[N[(N[(2.0 * l), $MachinePrecision] / Om), $MachinePrecision], 2.0], $MachinePrecision] * N[(N[Power[N[Sin[kx], $MachinePrecision], 2.0], $MachinePrecision] + N[Power[N[Sin[ky], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)}

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 5 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: 98.4% accurate, 1.0× speedup?

\[\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)} \]
(FPCore (l Om kx ky)
 :precision binary64
 (sqrt
  (*
   (/ 1.0 2.0)
   (+
    1.0
    (/
     1.0
     (sqrt
      (+
       1.0
       (*
        (pow (/ (* 2.0 l) Om) 2.0)
        (+ (pow (sin kx) 2.0) (pow (sin ky) 2.0))))))))))
double code(double l, double Om, double kx, double ky) {
	return sqrt(((1.0 / 2.0) * (1.0 + (1.0 / sqrt((1.0 + (pow(((2.0 * l) / Om), 2.0) * (pow(sin(kx), 2.0) + pow(sin(ky), 2.0)))))))));
}
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(l, om, kx, ky)
use fmin_fmax_functions
    real(8), intent (in) :: l
    real(8), intent (in) :: om
    real(8), intent (in) :: kx
    real(8), intent (in) :: ky
    code = sqrt(((1.0d0 / 2.0d0) * (1.0d0 + (1.0d0 / sqrt((1.0d0 + ((((2.0d0 * l) / om) ** 2.0d0) * ((sin(kx) ** 2.0d0) + (sin(ky) ** 2.0d0)))))))))
end function
public static double code(double l, double Om, double kx, double ky) {
	return Math.sqrt(((1.0 / 2.0) * (1.0 + (1.0 / Math.sqrt((1.0 + (Math.pow(((2.0 * l) / Om), 2.0) * (Math.pow(Math.sin(kx), 2.0) + Math.pow(Math.sin(ky), 2.0)))))))));
}
def code(l, Om, kx, ky):
	return math.sqrt(((1.0 / 2.0) * (1.0 + (1.0 / math.sqrt((1.0 + (math.pow(((2.0 * l) / Om), 2.0) * (math.pow(math.sin(kx), 2.0) + math.pow(math.sin(ky), 2.0)))))))))
function code(l, Om, kx, ky)
	return sqrt(Float64(Float64(1.0 / 2.0) * Float64(1.0 + Float64(1.0 / sqrt(Float64(1.0 + Float64((Float64(Float64(2.0 * l) / Om) ^ 2.0) * Float64((sin(kx) ^ 2.0) + (sin(ky) ^ 2.0)))))))))
end
function tmp = code(l, Om, kx, ky)
	tmp = sqrt(((1.0 / 2.0) * (1.0 + (1.0 / sqrt((1.0 + ((((2.0 * l) / Om) ^ 2.0) * ((sin(kx) ^ 2.0) + (sin(ky) ^ 2.0)))))))));
end
code[l_, Om_, kx_, ky_] := N[Sqrt[N[(N[(1.0 / 2.0), $MachinePrecision] * N[(1.0 + N[(1.0 / N[Sqrt[N[(1.0 + N[(N[Power[N[(N[(2.0 * l), $MachinePrecision] / Om), $MachinePrecision], 2.0], $MachinePrecision] * N[(N[Power[N[Sin[kx], $MachinePrecision], 2.0], $MachinePrecision] + N[Power[N[Sin[ky], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)}

Alternative 1: 98.5% accurate, 0.7× speedup?

\[\begin{array}{l} \mathbf{if}\;\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin \left(\mathsf{min}\left(kx, ky\right)\right)}^{2} + {\sin \left(\mathsf{max}\left(kx, ky\right)\right)}^{2}\right)} \leq 2:\\ \;\;\;\;\sqrt{\frac{0.5}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(\mathsf{min}\left(kx, ky\right) + \mathsf{min}\left(kx, ky\right)\right), -0.5, 0.5\right) \cdot \frac{\frac{\ell}{Om} \cdot \ell}{Om}, 4, 1\right)}} - -0.5}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{0.5}\\ \end{array} \]
(FPCore (l Om kx ky)
 :precision binary64
 (if (<=
      (sqrt
       (+
        1.0
        (*
         (pow (/ (* 2.0 l) Om) 2.0)
         (+ (pow (sin (fmin kx ky)) 2.0) (pow (sin (fmax kx ky)) 2.0)))))
      2.0)
   (sqrt
    (-
     (/
      0.5
      (sqrt
       (fma
        (*
         (fma (cos (+ (fmin kx ky) (fmin kx ky))) -0.5 0.5)
         (/ (* (/ l Om) l) Om))
        4.0
        1.0)))
     -0.5))
   (sqrt 0.5)))
double code(double l, double Om, double kx, double ky) {
	double tmp;
	if (sqrt((1.0 + (pow(((2.0 * l) / Om), 2.0) * (pow(sin(fmin(kx, ky)), 2.0) + pow(sin(fmax(kx, ky)), 2.0))))) <= 2.0) {
		tmp = sqrt(((0.5 / sqrt(fma((fma(cos((fmin(kx, ky) + fmin(kx, ky))), -0.5, 0.5) * (((l / Om) * l) / Om)), 4.0, 1.0))) - -0.5));
	} else {
		tmp = sqrt(0.5);
	}
	return tmp;
}
function code(l, Om, kx, ky)
	tmp = 0.0
	if (sqrt(Float64(1.0 + Float64((Float64(Float64(2.0 * l) / Om) ^ 2.0) * Float64((sin(fmin(kx, ky)) ^ 2.0) + (sin(fmax(kx, ky)) ^ 2.0))))) <= 2.0)
		tmp = sqrt(Float64(Float64(0.5 / sqrt(fma(Float64(fma(cos(Float64(fmin(kx, ky) + fmin(kx, ky))), -0.5, 0.5) * Float64(Float64(Float64(l / Om) * l) / Om)), 4.0, 1.0))) - -0.5));
	else
		tmp = sqrt(0.5);
	end
	return tmp
end
code[l_, Om_, kx_, ky_] := If[LessEqual[N[Sqrt[N[(1.0 + N[(N[Power[N[(N[(2.0 * l), $MachinePrecision] / Om), $MachinePrecision], 2.0], $MachinePrecision] * N[(N[Power[N[Sin[N[Min[kx, ky], $MachinePrecision]], $MachinePrecision], 2.0], $MachinePrecision] + N[Power[N[Sin[N[Max[kx, ky], $MachinePrecision]], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 2.0], N[Sqrt[N[(N[(0.5 / N[Sqrt[N[(N[(N[(N[Cos[N[(N[Min[kx, ky], $MachinePrecision] + N[Min[kx, ky], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * -0.5 + 0.5), $MachinePrecision] * N[(N[(N[(l / Om), $MachinePrecision] * l), $MachinePrecision] / Om), $MachinePrecision]), $MachinePrecision] * 4.0 + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - -0.5), $MachinePrecision]], $MachinePrecision], N[Sqrt[0.5], $MachinePrecision]]
\begin{array}{l}
\mathbf{if}\;\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin \left(\mathsf{min}\left(kx, ky\right)\right)}^{2} + {\sin \left(\mathsf{max}\left(kx, ky\right)\right)}^{2}\right)} \leq 2:\\
\;\;\;\;\sqrt{\frac{0.5}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(\mathsf{min}\left(kx, ky\right) + \mathsf{min}\left(kx, ky\right)\right), -0.5, 0.5\right) \cdot \frac{\frac{\ell}{Om} \cdot \ell}{Om}, 4, 1\right)}} - -0.5}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{0.5}\\


\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (sqrt.64 (+.f64 #s(literal 1 binary64) (*.f64 (pow.64 (/.f64 (*.f64 #s(literal 2 binary64) l) Om) #s(literal 2 binary64)) (+.f64 (pow.64 (sin.64 kx) #s(literal 2 binary64)) (pow.64 (sin.64 ky) #s(literal 2 binary64)))))) < 2

    1. Initial program 98.4%

      \[\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)} \]
    2. Taylor expanded in ky around 0

      \[\leadsto \sqrt{\color{blue}{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + 4 \cdot \frac{{\ell}^{2} \cdot {\sin kx}^{2}}{{Om}^{2}}}}\right)}} \]
    3. Step-by-step derivation
      1. metadata-evalN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{1} + \frac{1}{\sqrt{1 + 4 \cdot \frac{{\ell}^{2} \cdot {\sin kx}^{2}}{{Om}^{2}}}}\right)} \]
      2. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \color{blue}{\left(1 + \frac{1}{\sqrt{1 + 4 \cdot \frac{{\ell}^{2} \cdot {\sin kx}^{2}}{{Om}^{2}}}}\right)}} \]
      3. metadata-evalN/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(\color{blue}{1} + \frac{1}{\sqrt{1 + 4 \cdot \frac{{\ell}^{2} \cdot {\sin kx}^{2}}{{Om}^{2}}}}\right)} \]
      4. lower-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \color{blue}{\frac{1}{\sqrt{1 + 4 \cdot \frac{{\ell}^{2} \cdot {\sin kx}^{2}}{{Om}^{2}}}}}\right)} \]
      5. lower-/.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\color{blue}{\sqrt{1 + 4 \cdot \frac{{\ell}^{2} \cdot {\sin kx}^{2}}{{Om}^{2}}}}}\right)} \]
      6. lower-sqrt.64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + 4 \cdot \frac{{\ell}^{2} \cdot {\sin kx}^{2}}{{Om}^{2}}}}\right)} \]
      7. lower-+.f64N/A

        \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + 4 \cdot \frac{{\ell}^{2} \cdot {\sin kx}^{2}}{{Om}^{2}}}}\right)} \]
    4. Applied rewrites77.1%

      \[\leadsto \sqrt{\color{blue}{0.5 \cdot \left(1 + \frac{1}{\sqrt{1 + 4 \cdot \frac{{\ell}^{2} \cdot {\sin kx}^{2}}{{Om}^{2}}}}\right)}} \]
    5. Applied rewrites74.8%

      \[\leadsto \sqrt{\color{blue}{\frac{0.5}{\sqrt{\mathsf{fma}\left(\left(0.5 - 0.5 \cdot \cos \left(kx + kx\right)\right) \cdot \left(\frac{\ell}{Om \cdot Om} \cdot \ell\right), 4, 1\right)}} + 0.5}} \]
    6. Step-by-step derivation
      1. metadata-eval74.8%

        \[\leadsto \sqrt{\frac{\color{blue}{0.5}}{\sqrt{\mathsf{fma}\left(\left(0.5 - 0.5 \cdot \cos \left(kx + kx\right)\right) \cdot \left(\frac{\ell}{Om \cdot Om} \cdot \ell\right), 4, 1\right)}} + 0.5} \]
      2. metadata-eval74.8%

        \[\leadsto \sqrt{\frac{\color{blue}{0.5}}{\sqrt{\mathsf{fma}\left(\left(0.5 - 0.5 \cdot \cos \left(kx + kx\right)\right) \cdot \left(\frac{\ell}{Om \cdot Om} \cdot \ell\right), 4, 1\right)}} + 0.5} \]
      3. lift-+.f64N/A

        \[\leadsto \sqrt{\frac{\frac{1}{2}}{\sqrt{\mathsf{fma}\left(\left(\frac{1}{2} - \frac{1}{2} \cdot \cos \left(kx + kx\right)\right) \cdot \left(\frac{\ell}{Om \cdot Om} \cdot \ell\right), 4, 1\right)}} + \color{blue}{\frac{1}{2}}} \]
    7. Applied rewrites74.8%

      \[\leadsto \color{blue}{\sqrt{\frac{0.5}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), -0.5, 0.5\right) \cdot \left(\frac{\ell}{Om \cdot Om} \cdot \ell\right), 4, 1\right)}} - -0.5}} \]
    8. Step-by-step derivation
      1. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{\frac{1}{2}}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), \frac{-1}{2}, \frac{1}{2}\right) \cdot \left(\frac{\ell}{Om \cdot Om} \cdot \ell\right), 4, 1\right)}} - \frac{-1}{2}} \]
      2. lift-/.f64N/A

        \[\leadsto \sqrt{\frac{\frac{1}{2}}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), \frac{-1}{2}, \frac{1}{2}\right) \cdot \left(\frac{\ell}{Om \cdot Om} \cdot \ell\right), 4, 1\right)}} - \frac{-1}{2}} \]
      3. lift-*.f64N/A

        \[\leadsto \sqrt{\frac{\frac{1}{2}}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), \frac{-1}{2}, \frac{1}{2}\right) \cdot \left(\frac{\ell}{Om \cdot Om} \cdot \ell\right), 4, 1\right)}} - \frac{-1}{2}} \]
      4. associate-/r*N/A

        \[\leadsto \sqrt{\frac{\frac{1}{2}}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), \frac{-1}{2}, \frac{1}{2}\right) \cdot \left(\frac{\frac{\ell}{Om}}{Om} \cdot \ell\right), 4, 1\right)}} - \frac{-1}{2}} \]
      5. associate-*l/N/A

        \[\leadsto \sqrt{\frac{\frac{1}{2}}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), \frac{-1}{2}, \frac{1}{2}\right) \cdot \frac{\frac{\ell}{Om} \cdot \ell}{Om}, 4, 1\right)}} - \frac{-1}{2}} \]
      6. lower-/.f64N/A

        \[\leadsto \sqrt{\frac{\frac{1}{2}}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), \frac{-1}{2}, \frac{1}{2}\right) \cdot \frac{\frac{\ell}{Om} \cdot \ell}{Om}, 4, 1\right)}} - \frac{-1}{2}} \]
      7. lower-*.f64N/A

        \[\leadsto \sqrt{\frac{\frac{1}{2}}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), \frac{-1}{2}, \frac{1}{2}\right) \cdot \frac{\frac{\ell}{Om} \cdot \ell}{Om}, 4, 1\right)}} - \frac{-1}{2}} \]
      8. lower-/.f6479.1%

        \[\leadsto \sqrt{\frac{0.5}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), -0.5, 0.5\right) \cdot \frac{\frac{\ell}{Om} \cdot \ell}{Om}, 4, 1\right)}} - -0.5} \]
    9. Applied rewrites79.1%

      \[\leadsto \sqrt{\frac{0.5}{\sqrt{\mathsf{fma}\left(\mathsf{fma}\left(\cos \left(kx + kx\right), -0.5, 0.5\right) \cdot \frac{\frac{\ell}{Om} \cdot \ell}{Om}, 4, 1\right)}} - -0.5} \]

    if 2 < (sqrt.64 (+.f64 #s(literal 1 binary64) (*.f64 (pow.64 (/.f64 (*.f64 #s(literal 2 binary64) l) Om) #s(literal 2 binary64)) (+.f64 (pow.64 (sin.64 kx) #s(literal 2 binary64)) (pow.64 (sin.64 ky) #s(literal 2 binary64))))))

    1. Initial program 98.4%

      \[\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)} \]
    2. Taylor expanded in l around inf

      \[\leadsto \sqrt{\color{blue}{\frac{1}{2}}} \]
    3. Step-by-step derivation
      1. Applied rewrites56.5%

        \[\leadsto \sqrt{\color{blue}{0.5}} \]
    4. Recombined 2 regimes into one program.
    5. Add Preprocessing

    Alternative 2: 98.4% accurate, 1.1× speedup?

    \[\begin{array}{l} \mathbf{if}\;\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)} \leq 2:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;\sqrt{0.5}\\ \end{array} \]
    (FPCore (l Om kx ky)
     :precision binary64
     (if (<=
          (sqrt
           (+
            1.0
            (*
             (pow (/ (* 2.0 l) Om) 2.0)
             (+ (pow (sin kx) 2.0) (pow (sin ky) 2.0)))))
          2.0)
       1.0
       (sqrt 0.5)))
    double code(double l, double Om, double kx, double ky) {
    	double tmp;
    	if (sqrt((1.0 + (pow(((2.0 * l) / Om), 2.0) * (pow(sin(kx), 2.0) + pow(sin(ky), 2.0))))) <= 2.0) {
    		tmp = 1.0;
    	} else {
    		tmp = sqrt(0.5);
    	}
    	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(l, om, kx, ky)
    use fmin_fmax_functions
        real(8), intent (in) :: l
        real(8), intent (in) :: om
        real(8), intent (in) :: kx
        real(8), intent (in) :: ky
        real(8) :: tmp
        if (sqrt((1.0d0 + ((((2.0d0 * l) / om) ** 2.0d0) * ((sin(kx) ** 2.0d0) + (sin(ky) ** 2.0d0))))) <= 2.0d0) then
            tmp = 1.0d0
        else
            tmp = sqrt(0.5d0)
        end if
        code = tmp
    end function
    
    public static double code(double l, double Om, double kx, double ky) {
    	double tmp;
    	if (Math.sqrt((1.0 + (Math.pow(((2.0 * l) / Om), 2.0) * (Math.pow(Math.sin(kx), 2.0) + Math.pow(Math.sin(ky), 2.0))))) <= 2.0) {
    		tmp = 1.0;
    	} else {
    		tmp = Math.sqrt(0.5);
    	}
    	return tmp;
    }
    
    def code(l, Om, kx, ky):
    	tmp = 0
    	if math.sqrt((1.0 + (math.pow(((2.0 * l) / Om), 2.0) * (math.pow(math.sin(kx), 2.0) + math.pow(math.sin(ky), 2.0))))) <= 2.0:
    		tmp = 1.0
    	else:
    		tmp = math.sqrt(0.5)
    	return tmp
    
    function code(l, Om, kx, ky)
    	tmp = 0.0
    	if (sqrt(Float64(1.0 + Float64((Float64(Float64(2.0 * l) / Om) ^ 2.0) * Float64((sin(kx) ^ 2.0) + (sin(ky) ^ 2.0))))) <= 2.0)
    		tmp = 1.0;
    	else
    		tmp = sqrt(0.5);
    	end
    	return tmp
    end
    
    function tmp_2 = code(l, Om, kx, ky)
    	tmp = 0.0;
    	if (sqrt((1.0 + ((((2.0 * l) / Om) ^ 2.0) * ((sin(kx) ^ 2.0) + (sin(ky) ^ 2.0))))) <= 2.0)
    		tmp = 1.0;
    	else
    		tmp = sqrt(0.5);
    	end
    	tmp_2 = tmp;
    end
    
    code[l_, Om_, kx_, ky_] := If[LessEqual[N[Sqrt[N[(1.0 + N[(N[Power[N[(N[(2.0 * l), $MachinePrecision] / Om), $MachinePrecision], 2.0], $MachinePrecision] * N[(N[Power[N[Sin[kx], $MachinePrecision], 2.0], $MachinePrecision] + N[Power[N[Sin[ky], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], 2.0], 1.0, N[Sqrt[0.5], $MachinePrecision]]
    
    \begin{array}{l}
    \mathbf{if}\;\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)} \leq 2:\\
    \;\;\;\;1\\
    
    \mathbf{else}:\\
    \;\;\;\;\sqrt{0.5}\\
    
    
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (sqrt.64 (+.f64 #s(literal 1 binary64) (*.f64 (pow.64 (/.f64 (*.f64 #s(literal 2 binary64) l) Om) #s(literal 2 binary64)) (+.f64 (pow.64 (sin.64 kx) #s(literal 2 binary64)) (pow.64 (sin.64 ky) #s(literal 2 binary64)))))) < 2

      1. Initial program 98.4%

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)} \]
      2. Taylor expanded in l around 0

        \[\leadsto \color{blue}{1} \]
      3. Step-by-step derivation
        1. Applied rewrites62.1%

          \[\leadsto \color{blue}{1} \]

        if 2 < (sqrt.64 (+.f64 #s(literal 1 binary64) (*.f64 (pow.64 (/.f64 (*.f64 #s(literal 2 binary64) l) Om) #s(literal 2 binary64)) (+.f64 (pow.64 (sin.64 kx) #s(literal 2 binary64)) (pow.64 (sin.64 ky) #s(literal 2 binary64))))))

        1. Initial program 98.4%

          \[\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)} \]
        2. Taylor expanded in l around inf

          \[\leadsto \sqrt{\color{blue}{\frac{1}{2}}} \]
        3. Step-by-step derivation
          1. Applied rewrites56.5%

            \[\leadsto \sqrt{\color{blue}{0.5}} \]
        4. Recombined 2 regimes into one program.
        5. Add Preprocessing

        Alternative 3: 98.1% accurate, 1.5× speedup?

        \[\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot {\sin \left(\mathsf{max}\left(\left|kx\right|, \left|ky\right|\right)\right)}^{2}}}\right)} \]
        (FPCore (l Om kx ky)
         :precision binary64
         (sqrt
          (*
           (/ 1.0 2.0)
           (+
            1.0
            (/
             1.0
             (sqrt
              (+
               1.0
               (*
                (pow (/ (* 2.0 l) Om) 2.0)
                (pow (sin (fmax (fabs kx) (fabs ky))) 2.0)))))))))
        double code(double l, double Om, double kx, double ky) {
        	return sqrt(((1.0 / 2.0) * (1.0 + (1.0 / sqrt((1.0 + (pow(((2.0 * l) / Om), 2.0) * pow(sin(fmax(fabs(kx), fabs(ky))), 2.0))))))));
        }
        
        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(l, om, kx, ky)
        use fmin_fmax_functions
            real(8), intent (in) :: l
            real(8), intent (in) :: om
            real(8), intent (in) :: kx
            real(8), intent (in) :: ky
            code = sqrt(((1.0d0 / 2.0d0) * (1.0d0 + (1.0d0 / sqrt((1.0d0 + ((((2.0d0 * l) / om) ** 2.0d0) * (sin(fmax(abs(kx), abs(ky))) ** 2.0d0))))))))
        end function
        
        public static double code(double l, double Om, double kx, double ky) {
        	return Math.sqrt(((1.0 / 2.0) * (1.0 + (1.0 / Math.sqrt((1.0 + (Math.pow(((2.0 * l) / Om), 2.0) * Math.pow(Math.sin(fmax(Math.abs(kx), Math.abs(ky))), 2.0))))))));
        }
        
        def code(l, Om, kx, ky):
        	return math.sqrt(((1.0 / 2.0) * (1.0 + (1.0 / math.sqrt((1.0 + (math.pow(((2.0 * l) / Om), 2.0) * math.pow(math.sin(fmax(math.fabs(kx), math.fabs(ky))), 2.0))))))))
        
        function code(l, Om, kx, ky)
        	return sqrt(Float64(Float64(1.0 / 2.0) * Float64(1.0 + Float64(1.0 / sqrt(Float64(1.0 + Float64((Float64(Float64(2.0 * l) / Om) ^ 2.0) * (sin(fmax(abs(kx), abs(ky))) ^ 2.0))))))))
        end
        
        function tmp = code(l, Om, kx, ky)
        	tmp = sqrt(((1.0 / 2.0) * (1.0 + (1.0 / sqrt((1.0 + ((((2.0 * l) / Om) ^ 2.0) * (sin(max(abs(kx), abs(ky))) ^ 2.0))))))));
        end
        
        code[l_, Om_, kx_, ky_] := N[Sqrt[N[(N[(1.0 / 2.0), $MachinePrecision] * N[(1.0 + N[(1.0 / N[Sqrt[N[(1.0 + N[(N[Power[N[(N[(2.0 * l), $MachinePrecision] / Om), $MachinePrecision], 2.0], $MachinePrecision] * N[Power[N[Sin[N[Max[N[Abs[kx], $MachinePrecision], N[Abs[ky], $MachinePrecision]], $MachinePrecision]], $MachinePrecision], 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
        
        \sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot {\sin \left(\mathsf{max}\left(\left|kx\right|, \left|ky\right|\right)\right)}^{2}}}\right)}
        
        Derivation
        1. Initial program 98.4%

          \[\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)} \]
        2. Taylor expanded in kx around 0

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \color{blue}{{\sin ky}^{2}}}}\right)} \]
        3. Step-by-step derivation
          1. lower-pow.64N/A

            \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot {\sin ky}^{\color{blue}{2}}}}\right)} \]
          2. lower-sin.6488.8%

            \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot {\sin ky}^{2}}}\right)} \]
        4. Applied rewrites88.8%

          \[\leadsto \sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \color{blue}{{\sin ky}^{2}}}}\right)} \]
        5. Add Preprocessing

        Alternative 4: 62.1% accurate, 142.7× speedup?

        \[1 \]
        (FPCore (l Om kx ky) :precision binary64 1.0)
        double code(double l, double Om, double kx, double ky) {
        	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(l, om, kx, ky)
        use fmin_fmax_functions
            real(8), intent (in) :: l
            real(8), intent (in) :: om
            real(8), intent (in) :: kx
            real(8), intent (in) :: ky
            code = 1.0d0
        end function
        
        public static double code(double l, double Om, double kx, double ky) {
        	return 1.0;
        }
        
        def code(l, Om, kx, ky):
        	return 1.0
        
        function code(l, Om, kx, ky)
        	return 1.0
        end
        
        function tmp = code(l, Om, kx, ky)
        	tmp = 1.0;
        end
        
        code[l_, Om_, kx_, ky_] := 1.0
        
        1
        
        Derivation
        1. Initial program 98.4%

          \[\sqrt{\frac{1}{2} \cdot \left(1 + \frac{1}{\sqrt{1 + {\left(\frac{2 \cdot \ell}{Om}\right)}^{2} \cdot \left({\sin kx}^{2} + {\sin ky}^{2}\right)}}\right)} \]
        2. Taylor expanded in l around 0

          \[\leadsto \color{blue}{1} \]
        3. Step-by-step derivation
          1. Applied rewrites62.1%

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

          Reproduce

          ?
          herbie shell --seed 2025183 
          (FPCore (l Om kx ky)
            :name "Toniolo and Linder, Equation (3a)"
            :precision binary64
            (sqrt (* (/ 1.0 2.0) (+ 1.0 (/ 1.0 (sqrt (+ 1.0 (* (pow (/ (* 2.0 l) Om) 2.0) (+ (pow (sin kx) 2.0) (pow (sin ky) 2.0))))))))))