
(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 5 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 (/ (pow (* n (+ PI PI)) (+ (* -0.5 k) 0.5)) (sqrt k)))
double code(double k, double n) {
return pow((n * (((double) M_PI) + ((double) M_PI))), ((-0.5 * k) + 0.5)) / sqrt(k);
}
public static double code(double k, double n) {
return Math.pow((n * (Math.PI + Math.PI)), ((-0.5 * k) + 0.5)) / Math.sqrt(k);
}
def code(k, n): return math.pow((n * (math.pi + math.pi)), ((-0.5 * k) + 0.5)) / math.sqrt(k)
function code(k, n) return Float64((Float64(n * Float64(pi + pi)) ^ Float64(Float64(-0.5 * k) + 0.5)) / sqrt(k)) end
function tmp = code(k, n) tmp = ((n * (pi + pi)) ^ ((-0.5 * k) + 0.5)) / sqrt(k); end
code[k_, n_] := N[(N[Power[N[(n * N[(Pi + Pi), $MachinePrecision]), $MachinePrecision], N[(N[(-0.5 * k), $MachinePrecision] + 0.5), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{{\left(n \cdot \left(\pi + \pi\right)\right)}^{\left(-0.5 \cdot k + 0.5\right)}}{\sqrt{k}}
\end{array}
Initial program 99.2%
lift-*.f64N/A
lift-/.f64N/A
lift-sqrt.f64N/A
lift-pow.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift--.f64N/A
lift-/.f64N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites99.3%
Taylor expanded in k around 0
+-commutativeN/A
lower-+.f64N/A
lower-*.f6499.3
Applied rewrites99.3%
lift-*.f64N/A
*-lft-identity99.3
lift-*.f64N/A
*-commutativeN/A
lower-*.f6499.3
Applied rewrites99.3%
lift-PI.f64N/A
lift-*.f64N/A
*-commutativeN/A
count-2-revN/A
lower-+.f64N/A
lift-PI.f64N/A
lift-PI.f6499.3
Applied rewrites99.3%
(FPCore (k n) :precision binary64 (if (<= (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))) 5e+147) (sqrt (* PI (* (/ n k) 2.0))) (/ (sqrt (* (* 2.0 k) (* PI n))) k)))
double code(double k, double n) {
double tmp;
if (((1.0 / sqrt(k)) * pow(((2.0 * ((double) M_PI)) * n), ((1.0 - k) / 2.0))) <= 5e+147) {
tmp = sqrt((((double) M_PI) * ((n / k) * 2.0)));
} else {
tmp = sqrt(((2.0 * k) * (((double) M_PI) * n))) / k;
}
return tmp;
}
public static double code(double k, double n) {
double tmp;
if (((1.0 / Math.sqrt(k)) * Math.pow(((2.0 * Math.PI) * n), ((1.0 - k) / 2.0))) <= 5e+147) {
tmp = Math.sqrt((Math.PI * ((n / k) * 2.0)));
} else {
tmp = Math.sqrt(((2.0 * k) * (Math.PI * n))) / k;
}
return tmp;
}
def code(k, n): tmp = 0 if ((1.0 / math.sqrt(k)) * math.pow(((2.0 * math.pi) * n), ((1.0 - k) / 2.0))) <= 5e+147: tmp = math.sqrt((math.pi * ((n / k) * 2.0))) else: tmp = math.sqrt(((2.0 * k) * (math.pi * n))) / k return tmp
function code(k, n) tmp = 0.0 if (Float64(Float64(1.0 / sqrt(k)) * (Float64(Float64(2.0 * pi) * n) ^ Float64(Float64(1.0 - k) / 2.0))) <= 5e+147) tmp = sqrt(Float64(pi * Float64(Float64(n / k) * 2.0))); else tmp = Float64(sqrt(Float64(Float64(2.0 * k) * Float64(pi * n))) / k); end return tmp end
function tmp_2 = code(k, n) tmp = 0.0; if (((1.0 / sqrt(k)) * (((2.0 * pi) * n) ^ ((1.0 - k) / 2.0))) <= 5e+147) tmp = sqrt((pi * ((n / k) * 2.0))); else tmp = sqrt(((2.0 * k) * (pi * n))) / k; end tmp_2 = tmp; end
code[k_, n_] := If[LessEqual[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], 5e+147], N[Sqrt[N[(Pi * N[(N[(n / k), $MachinePrecision] * 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[(N[Sqrt[N[(N[(2.0 * k), $MachinePrecision] * N[(Pi * n), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / k), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \leq 5 \cdot 10^{+147}:\\
\;\;\;\;\sqrt{\pi \cdot \left(\frac{n}{k} \cdot 2\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{\sqrt{\left(2 \cdot k\right) \cdot \left(\pi \cdot n\right)}}{k}\\
\end{array}
\end{array}
if (*.f64 (/.f64 #s(literal 1 binary64) (sqrt.f64 k)) (pow.f64 (*.f64 (*.f64 #s(literal 2 binary64) (PI.f64)) n) (/.f64 (-.f64 #s(literal 1 binary64) k) #s(literal 2 binary64)))) < 5.0000000000000002e147Initial program 98.9%
Taylor expanded in k around 0
sqrt-unprodN/A
lower-sqrt.f64N/A
lower-*.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lift-PI.f6454.8
Applied rewrites54.8%
lift-/.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
associate-/l*N/A
lower-*.f64N/A
lift-PI.f64N/A
lower-/.f6454.9
Applied rewrites54.9%
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
associate-*l*N/A
lower-*.f64N/A
lift-PI.f64N/A
lower-*.f6454.9
Applied rewrites54.9%
if 5.0000000000000002e147 < (*.f64 (/.f64 #s(literal 1 binary64) (sqrt.f64 k)) (pow.f64 (*.f64 (*.f64 #s(literal 2 binary64) (PI.f64)) n) (/.f64 (-.f64 #s(literal 1 binary64) k) #s(literal 2 binary64)))) Initial program 99.8%
Taylor expanded in k around 0
lower-/.f64N/A
Applied rewrites83.6%
Taylor expanded in k around 0
*-commutativeN/A
lift-*.f64N/A
lift-PI.f64N/A
*-commutativeN/A
lift-*.f64N/A
sqrt-prodN/A
lift-*.f64N/A
lift-sqrt.f6437.6
lift-*.f64N/A
*-commutativeN/A
lift-*.f64N/A
*-commutativeN/A
lift-PI.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-*r*N/A
Applied rewrites37.6%
(FPCore (k n) :precision binary64 (let* ((t_0 (* n (* PI 2.0)))) (if (<= k 1.0) (/ (sqrt t_0) (sqrt k)) (/ (pow t_0 (* -0.5 k)) (sqrt k)))))
double code(double k, double n) {
double t_0 = n * (((double) M_PI) * 2.0);
double tmp;
if (k <= 1.0) {
tmp = sqrt(t_0) / sqrt(k);
} else {
tmp = pow(t_0, (-0.5 * k)) / sqrt(k);
}
return tmp;
}
public static double code(double k, double n) {
double t_0 = n * (Math.PI * 2.0);
double tmp;
if (k <= 1.0) {
tmp = Math.sqrt(t_0) / Math.sqrt(k);
} else {
tmp = Math.pow(t_0, (-0.5 * k)) / Math.sqrt(k);
}
return tmp;
}
def code(k, n): t_0 = n * (math.pi * 2.0) tmp = 0 if k <= 1.0: tmp = math.sqrt(t_0) / math.sqrt(k) else: tmp = math.pow(t_0, (-0.5 * k)) / math.sqrt(k) return tmp
function code(k, n) t_0 = Float64(n * Float64(pi * 2.0)) tmp = 0.0 if (k <= 1.0) tmp = Float64(sqrt(t_0) / sqrt(k)); else tmp = Float64((t_0 ^ Float64(-0.5 * k)) / sqrt(k)); end return tmp end
function tmp_2 = code(k, n) t_0 = n * (pi * 2.0); tmp = 0.0; if (k <= 1.0) tmp = sqrt(t_0) / sqrt(k); else tmp = (t_0 ^ (-0.5 * k)) / sqrt(k); end tmp_2 = tmp; end
code[k_, n_] := Block[{t$95$0 = N[(n * N[(Pi * 2.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[k, 1.0], N[(N[Sqrt[t$95$0], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision], N[(N[Power[t$95$0, N[(-0.5 * k), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := n \cdot \left(\pi \cdot 2\right)\\
\mathbf{if}\;k \leq 1:\\
\;\;\;\;\frac{\sqrt{t\_0}}{\sqrt{k}}\\
\mathbf{else}:\\
\;\;\;\;\frac{{t\_0}^{\left(-0.5 \cdot k\right)}}{\sqrt{k}}\\
\end{array}
\end{array}
if k < 1Initial program 98.5%
lift-*.f64N/A
lift-/.f64N/A
lift-sqrt.f64N/A
lift-pow.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift--.f64N/A
lift-/.f64N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites98.6%
Taylor expanded in k around 0
*-lft-identityN/A
*-commutativeN/A
sqrt-unprodN/A
*-commutativeN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift-sqrt.f6492.5
lift-*.f64N/A
*-commutativeN/A
lower-*.f6492.5
Applied rewrites92.5%
if 1 < k Initial program 100.0%
lift-*.f64N/A
lift-/.f64N/A
lift-sqrt.f64N/A
lift-pow.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift--.f64N/A
lift-/.f64N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites100.0%
Taylor expanded in k around 0
+-commutativeN/A
lower-+.f64N/A
lower-*.f64100.0
Applied rewrites100.0%
lift-*.f64N/A
*-lft-identity100.0
lift-*.f64N/A
*-commutativeN/A
lower-*.f64100.0
Applied rewrites100.0%
Taylor expanded in k around inf
lift-*.f6499.3
Applied rewrites99.3%
(FPCore (k n) :precision binary64 (/ (sqrt (* n (* PI 2.0))) (sqrt k)))
double code(double k, double n) {
return sqrt((n * (((double) M_PI) * 2.0))) / sqrt(k);
}
public static double code(double k, double n) {
return Math.sqrt((n * (Math.PI * 2.0))) / Math.sqrt(k);
}
def code(k, n): return math.sqrt((n * (math.pi * 2.0))) / math.sqrt(k)
function code(k, n) return Float64(sqrt(Float64(n * Float64(pi * 2.0))) / sqrt(k)) end
function tmp = code(k, n) tmp = sqrt((n * (pi * 2.0))) / sqrt(k); end
code[k_, n_] := N[(N[Sqrt[N[(n * N[(Pi * 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sqrt{n \cdot \left(\pi \cdot 2\right)}}{\sqrt{k}}
\end{array}
Initial program 99.2%
lift-*.f64N/A
lift-/.f64N/A
lift-sqrt.f64N/A
lift-pow.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift--.f64N/A
lift-/.f64N/A
associate-*l/N/A
lower-/.f64N/A
Applied rewrites99.3%
Taylor expanded in k around 0
*-lft-identityN/A
*-commutativeN/A
sqrt-unprodN/A
*-commutativeN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift-sqrt.f6448.3
lift-*.f64N/A
*-commutativeN/A
lower-*.f6448.3
Applied rewrites48.3%
(FPCore (k n) :precision binary64 (sqrt (* PI (* (/ n k) 2.0))))
double code(double k, double n) {
return sqrt((((double) M_PI) * ((n / k) * 2.0)));
}
public static double code(double k, double n) {
return Math.sqrt((Math.PI * ((n / k) * 2.0)));
}
def code(k, n): return math.sqrt((math.pi * ((n / k) * 2.0)))
function code(k, n) return sqrt(Float64(pi * Float64(Float64(n / k) * 2.0))) end
function tmp = code(k, n) tmp = sqrt((pi * ((n / k) * 2.0))); end
code[k_, n_] := N[Sqrt[N[(Pi * N[(N[(n / k), $MachinePrecision] * 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\pi \cdot \left(\frac{n}{k} \cdot 2\right)}
\end{array}
Initial program 99.2%
Taylor expanded in k around 0
sqrt-unprodN/A
lower-sqrt.f64N/A
lower-*.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lift-PI.f6436.3
Applied rewrites36.3%
lift-/.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
associate-/l*N/A
lower-*.f64N/A
lift-PI.f64N/A
lower-/.f6436.3
Applied rewrites36.3%
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
associate-*l*N/A
lower-*.f64N/A
lift-PI.f64N/A
lower-*.f6436.3
Applied rewrites36.3%
herbie shell --seed 2025058
(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))))