
(FPCore (k n) :precision binary64 (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))
double code(double k, double n) {
return (1.0 / sqrt(k)) * pow(((2.0 * ((double) M_PI)) * n), ((1.0 - k) / 2.0));
}
public static double code(double k, double n) {
return (1.0 / Math.sqrt(k)) * Math.pow(((2.0 * Math.PI) * n), ((1.0 - k) / 2.0));
}
def code(k, n): return (1.0 / math.sqrt(k)) * math.pow(((2.0 * math.pi) * n), ((1.0 - k) / 2.0))
function code(k, n) return Float64(Float64(1.0 / sqrt(k)) * (Float64(Float64(2.0 * pi) * n) ^ Float64(Float64(1.0 - k) / 2.0))) end
function tmp = code(k, n) tmp = (1.0 / sqrt(k)) * (((2.0 * pi) * n) ^ ((1.0 - k) / 2.0)); end
code[k_, n_] := N[(N[(1.0 / N[Sqrt[k], $MachinePrecision]), $MachinePrecision] * N[Power[N[(N[(2.0 * Pi), $MachinePrecision] * n), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (k n) :precision binary64 (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))
double code(double k, double n) {
return (1.0 / sqrt(k)) * pow(((2.0 * ((double) M_PI)) * n), ((1.0 - k) / 2.0));
}
public static double code(double k, double n) {
return (1.0 / Math.sqrt(k)) * Math.pow(((2.0 * Math.PI) * n), ((1.0 - k) / 2.0));
}
def code(k, n): return (1.0 / math.sqrt(k)) * math.pow(((2.0 * math.pi) * n), ((1.0 - k) / 2.0))
function code(k, n) return Float64(Float64(1.0 / sqrt(k)) * (Float64(Float64(2.0 * pi) * n) ^ Float64(Float64(1.0 - k) / 2.0))) end
function tmp = code(k, n) tmp = (1.0 / sqrt(k)) * (((2.0 * pi) * n) ^ ((1.0 - k) / 2.0)); end
code[k_, n_] := N[(N[(1.0 / N[Sqrt[k], $MachinePrecision]), $MachinePrecision] * N[Power[N[(N[(2.0 * Pi), $MachinePrecision] * n), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}
\end{array}
(FPCore (k n) :precision binary64 (* (sqrt (* n 2.0)) (sqrt (/ PI (* k (pow (* PI (* n 2.0)) k))))))
double code(double k, double n) {
return sqrt((n * 2.0)) * sqrt((((double) M_PI) / (k * pow((((double) M_PI) * (n * 2.0)), k))));
}
public static double code(double k, double n) {
return Math.sqrt((n * 2.0)) * Math.sqrt((Math.PI / (k * Math.pow((Math.PI * (n * 2.0)), k))));
}
def code(k, n): return math.sqrt((n * 2.0)) * math.sqrt((math.pi / (k * math.pow((math.pi * (n * 2.0)), k))))
function code(k, n) return Float64(sqrt(Float64(n * 2.0)) * sqrt(Float64(pi / Float64(k * (Float64(pi * Float64(n * 2.0)) ^ k))))) end
function tmp = code(k, n) tmp = sqrt((n * 2.0)) * sqrt((pi / (k * ((pi * (n * 2.0)) ^ k)))); end
code[k_, n_] := N[(N[Sqrt[N[(n * 2.0), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(Pi / N[(k * N[Power[N[(Pi * N[(n * 2.0), $MachinePrecision]), $MachinePrecision], k], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{n \cdot 2} \cdot \sqrt{\frac{\pi}{k \cdot {\left(\pi \cdot \left(n \cdot 2\right)\right)}^{k}}}
\end{array}
Initial program 99.4%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lift-pow.f64N/A
lift-/.f64N/A
lift--.f64N/A
div-subN/A
metadata-evalN/A
pow-subN/A
associate-/l/N/A
lower-/.f64N/A
Applied rewrites99.7%
lift-*.f64N/A
lift-sqrt.f64N/A
lift-pow.f64N/A
lift-*.f64N/A
pow-unpowN/A
unpow1/2N/A
sqrt-unprodN/A
lower-sqrt.f64N/A
lower-*.f64N/A
lower-pow.f6499.7
Applied rewrites99.7%
lift-/.f64N/A
lift-sqrt.f64N/A
lift-sqrt.f64N/A
sqrt-undivN/A
lift-*.f64N/A
lift-*.f64N/A
associate-*r*N/A
lift-PI.f64N/A
*-commutativeN/A
associate-/l*N/A
sqrt-prodN/A
pow1/2N/A
lower-*.f64N/A
pow1/2N/A
lower-sqrt.f64N/A
Applied rewrites99.7%
lift-*.f64N/A
lift-sqrt.f64N/A
lift-sqrt.f64N/A
sqrt-unprodN/A
pow1/2N/A
lift-/.f64N/A
lift-*.f64N/A
associate-/l*N/A
associate-*r*N/A
unpow-prod-downN/A
lower-*.f64N/A
Applied rewrites99.7%
Final simplification99.7%
(FPCore (k n) :precision binary64 (* (sqrt n) (sqrt (/ (* 2.0 PI) (* k (pow (* 2.0 (* n PI)) k))))))
double code(double k, double n) {
return sqrt(n) * sqrt(((2.0 * ((double) M_PI)) / (k * pow((2.0 * (n * ((double) M_PI))), k))));
}
public static double code(double k, double n) {
return Math.sqrt(n) * Math.sqrt(((2.0 * Math.PI) / (k * Math.pow((2.0 * (n * Math.PI)), k))));
}
def code(k, n): return math.sqrt(n) * math.sqrt(((2.0 * math.pi) / (k * math.pow((2.0 * (n * math.pi)), k))))
function code(k, n) return Float64(sqrt(n) * sqrt(Float64(Float64(2.0 * pi) / Float64(k * (Float64(2.0 * Float64(n * pi)) ^ k))))) end
function tmp = code(k, n) tmp = sqrt(n) * sqrt(((2.0 * pi) / (k * ((2.0 * (n * pi)) ^ k)))); end
code[k_, n_] := N[(N[Sqrt[n], $MachinePrecision] * N[Sqrt[N[(N[(2.0 * Pi), $MachinePrecision] / N[(k * N[Power[N[(2.0 * N[(n * Pi), $MachinePrecision]), $MachinePrecision], k], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{n} \cdot \sqrt{\frac{2 \cdot \pi}{k \cdot {\left(2 \cdot \left(n \cdot \pi\right)\right)}^{k}}}
\end{array}
Initial program 99.4%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lift-pow.f64N/A
lift-/.f64N/A
lift--.f64N/A
div-subN/A
metadata-evalN/A
pow-subN/A
associate-/l/N/A
lower-/.f64N/A
Applied rewrites99.7%
lift-*.f64N/A
lift-sqrt.f64N/A
lift-pow.f64N/A
lift-*.f64N/A
pow-unpowN/A
unpow1/2N/A
sqrt-unprodN/A
lower-sqrt.f64N/A
lower-*.f64N/A
lower-pow.f6499.7
Applied rewrites99.7%
lift-/.f64N/A
lift-sqrt.f64N/A
lift-sqrt.f64N/A
sqrt-undivN/A
lift-*.f64N/A
lift-*.f64N/A
associate-*r*N/A
lift-PI.f64N/A
*-commutativeN/A
associate-/l*N/A
sqrt-prodN/A
pow1/2N/A
lower-*.f64N/A
pow1/2N/A
lower-sqrt.f64N/A
Applied rewrites99.7%
Final simplification99.7%
(FPCore (k n) :precision binary64 (if (<= k 1.0) (* (sqrt (/ 2.0 k)) (sqrt (* n PI))) (/ (pow (* 2.0 (* n PI)) (* k -0.5)) (sqrt k))))
double code(double k, double n) {
double tmp;
if (k <= 1.0) {
tmp = sqrt((2.0 / k)) * sqrt((n * ((double) M_PI)));
} else {
tmp = pow((2.0 * (n * ((double) M_PI))), (k * -0.5)) / sqrt(k);
}
return tmp;
}
public static double code(double k, double n) {
double tmp;
if (k <= 1.0) {
tmp = Math.sqrt((2.0 / k)) * Math.sqrt((n * Math.PI));
} else {
tmp = Math.pow((2.0 * (n * Math.PI)), (k * -0.5)) / Math.sqrt(k);
}
return tmp;
}
def code(k, n): tmp = 0 if k <= 1.0: tmp = math.sqrt((2.0 / k)) * math.sqrt((n * math.pi)) else: tmp = math.pow((2.0 * (n * math.pi)), (k * -0.5)) / math.sqrt(k) return tmp
function code(k, n) tmp = 0.0 if (k <= 1.0) tmp = Float64(sqrt(Float64(2.0 / k)) * sqrt(Float64(n * pi))); else tmp = Float64((Float64(2.0 * Float64(n * pi)) ^ Float64(k * -0.5)) / sqrt(k)); end return tmp end
function tmp_2 = code(k, n) tmp = 0.0; if (k <= 1.0) tmp = sqrt((2.0 / k)) * sqrt((n * pi)); else tmp = ((2.0 * (n * pi)) ^ (k * -0.5)) / sqrt(k); end tmp_2 = tmp; end
code[k_, n_] := If[LessEqual[k, 1.0], N[(N[Sqrt[N[(2.0 / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(n * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[Power[N[(2.0 * N[(n * Pi), $MachinePrecision]), $MachinePrecision], N[(k * -0.5), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;k \leq 1:\\
\;\;\;\;\sqrt{\frac{2}{k}} \cdot \sqrt{n \cdot \pi}\\
\mathbf{else}:\\
\;\;\;\;\frac{{\left(2 \cdot \left(n \cdot \pi\right)\right)}^{\left(k \cdot -0.5\right)}}{\sqrt{k}}\\
\end{array}
\end{array}
if k < 1Initial program 98.7%
Taylor expanded in k around 0
lower-*.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-PI.f64N/A
lower-sqrt.f6470.5
Applied rewrites70.5%
Applied rewrites70.5%
Applied rewrites96.5%
if 1 < k Initial program 100.0%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lift-pow.f64N/A
lift-/.f64N/A
lift--.f64N/A
div-subN/A
metadata-evalN/A
pow-subN/A
associate-/l/N/A
lower-/.f64N/A
Applied rewrites100.0%
lift-/.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
Applied rewrites100.0%
Taylor expanded in k around inf
*-commutativeN/A
lower-*.f64100.0
Applied rewrites100.0%
Final simplification98.3%
(FPCore (k n) :precision binary64 (/ (pow (* 2.0 (* n PI)) (fma k -0.5 0.5)) (sqrt k)))
double code(double k, double n) {
return pow((2.0 * (n * ((double) M_PI))), fma(k, -0.5, 0.5)) / sqrt(k);
}
function code(k, n) return Float64((Float64(2.0 * Float64(n * pi)) ^ fma(k, -0.5, 0.5)) / sqrt(k)) end
code[k_, n_] := N[(N[Power[N[(2.0 * N[(n * Pi), $MachinePrecision]), $MachinePrecision], N[(k * -0.5 + 0.5), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{{\left(2 \cdot \left(n \cdot \pi\right)\right)}^{\left(\mathsf{fma}\left(k, -0.5, 0.5\right)\right)}}{\sqrt{k}}
\end{array}
Initial program 99.4%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lift-pow.f64N/A
lift-/.f64N/A
lift--.f64N/A
div-subN/A
metadata-evalN/A
pow-subN/A
associate-/l/N/A
lower-/.f64N/A
Applied rewrites99.7%
lift-*.f64N/A
lift-sqrt.f64N/A
lift-pow.f64N/A
lift-*.f64N/A
pow-unpowN/A
unpow1/2N/A
sqrt-unprodN/A
lower-sqrt.f64N/A
lower-*.f64N/A
lower-pow.f6499.7
Applied rewrites99.7%
lift-/.f64N/A
lift-sqrt.f64N/A
lift-*.f64N/A
sqrt-prodN/A
lift-sqrt.f64N/A
pow1/2N/A
lift-pow.f64N/A
pow-unpowN/A
lift-*.f64N/A
associate-/l/N/A
Applied rewrites99.4%
Final simplification99.4%
(FPCore (k n) :precision binary64 (* (sqrt (/ 2.0 k)) (sqrt (* n PI))))
double code(double k, double n) {
return sqrt((2.0 / k)) * sqrt((n * ((double) M_PI)));
}
public static double code(double k, double n) {
return Math.sqrt((2.0 / k)) * Math.sqrt((n * Math.PI));
}
def code(k, n): return math.sqrt((2.0 / k)) * math.sqrt((n * math.pi))
function code(k, n) return Float64(sqrt(Float64(2.0 / k)) * sqrt(Float64(n * pi))) end
function tmp = code(k, n) tmp = sqrt((2.0 / k)) * sqrt((n * pi)); end
code[k_, n_] := N[(N[Sqrt[N[(2.0 / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(n * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\frac{2}{k}} \cdot \sqrt{n \cdot \pi}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
lower-*.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-PI.f64N/A
lower-sqrt.f6436.0
Applied rewrites36.0%
Applied rewrites36.1%
Applied rewrites48.9%
Final simplification48.9%
(FPCore (k n) :precision binary64 (* (sqrt n) (sqrt (* 2.0 (/ PI k)))))
double code(double k, double n) {
return sqrt(n) * sqrt((2.0 * (((double) M_PI) / k)));
}
public static double code(double k, double n) {
return Math.sqrt(n) * Math.sqrt((2.0 * (Math.PI / k)));
}
def code(k, n): return math.sqrt(n) * math.sqrt((2.0 * (math.pi / k)))
function code(k, n) return Float64(sqrt(n) * sqrt(Float64(2.0 * Float64(pi / k)))) end
function tmp = code(k, n) tmp = sqrt(n) * sqrt((2.0 * (pi / k))); end
code[k_, n_] := N[(N[Sqrt[n], $MachinePrecision] * N[Sqrt[N[(2.0 * N[(Pi / k), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{n} \cdot \sqrt{2 \cdot \frac{\pi}{k}}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
lower-*.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-PI.f64N/A
lower-sqrt.f6436.0
Applied rewrites36.0%
Applied rewrites48.8%
Final simplification48.8%
(FPCore (k n) :precision binary64 (sqrt (* (* 2.0 PI) (/ n k))))
double code(double k, double n) {
return sqrt(((2.0 * ((double) M_PI)) * (n / k)));
}
public static double code(double k, double n) {
return Math.sqrt(((2.0 * Math.PI) * (n / k)));
}
def code(k, n): return math.sqrt(((2.0 * math.pi) * (n / k)))
function code(k, n) return sqrt(Float64(Float64(2.0 * pi) * Float64(n / k))) end
function tmp = code(k, n) tmp = sqrt(((2.0 * pi) * (n / k))); end
code[k_, n_] := N[Sqrt[N[(N[(2.0 * Pi), $MachinePrecision] * N[(n / k), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\left(2 \cdot \pi\right) \cdot \frac{n}{k}}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
lower-*.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-PI.f64N/A
lower-sqrt.f6436.0
Applied rewrites36.0%
Applied rewrites36.1%
Applied rewrites36.1%
(FPCore (k n) :precision binary64 (sqrt (* n (/ (* 2.0 PI) k))))
double code(double k, double n) {
return sqrt((n * ((2.0 * ((double) M_PI)) / k)));
}
public static double code(double k, double n) {
return Math.sqrt((n * ((2.0 * Math.PI) / k)));
}
def code(k, n): return math.sqrt((n * ((2.0 * math.pi) / k)))
function code(k, n) return sqrt(Float64(n * Float64(Float64(2.0 * pi) / k))) end
function tmp = code(k, n) tmp = sqrt((n * ((2.0 * pi) / k))); end
code[k_, n_] := N[Sqrt[N[(n * N[(N[(2.0 * Pi), $MachinePrecision] / k), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{n \cdot \frac{2 \cdot \pi}{k}}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
lower-*.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-PI.f64N/A
lower-sqrt.f6436.0
Applied rewrites36.0%
Applied rewrites36.1%
Applied rewrites36.1%
(FPCore (k n) :precision binary64 (sqrt (* n (* PI (/ 2.0 k)))))
double code(double k, double n) {
return sqrt((n * (((double) M_PI) * (2.0 / k))));
}
public static double code(double k, double n) {
return Math.sqrt((n * (Math.PI * (2.0 / k))));
}
def code(k, n): return math.sqrt((n * (math.pi * (2.0 / k))))
function code(k, n) return sqrt(Float64(n * Float64(pi * Float64(2.0 / k)))) end
function tmp = code(k, n) tmp = sqrt((n * (pi * (2.0 / k)))); end
code[k_, n_] := N[Sqrt[N[(n * N[(Pi * N[(2.0 / k), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{n \cdot \left(\pi \cdot \frac{2}{k}\right)}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
lower-*.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-PI.f64N/A
lower-sqrt.f6436.0
Applied rewrites36.0%
Applied rewrites36.1%
Applied rewrites36.1%
Applied rewrites36.1%
herbie shell --seed 2024231
(FPCore (k n)
:name "Migdal et al, Equation (51)"
:precision binary64
(* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))