
(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 8 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 (if (<= k 4.3e-65) (* (sqrt (/ PI k)) (sqrt (* n 2.0))) (sqrt (/ (pow (* PI (* n 2.0)) (- 1.0 k)) k))))
double code(double k, double n) {
double tmp;
if (k <= 4.3e-65) {
tmp = sqrt((((double) M_PI) / k)) * sqrt((n * 2.0));
} else {
tmp = sqrt((pow((((double) M_PI) * (n * 2.0)), (1.0 - k)) / k));
}
return tmp;
}
public static double code(double k, double n) {
double tmp;
if (k <= 4.3e-65) {
tmp = Math.sqrt((Math.PI / k)) * Math.sqrt((n * 2.0));
} else {
tmp = Math.sqrt((Math.pow((Math.PI * (n * 2.0)), (1.0 - k)) / k));
}
return tmp;
}
def code(k, n): tmp = 0 if k <= 4.3e-65: tmp = math.sqrt((math.pi / k)) * math.sqrt((n * 2.0)) else: tmp = math.sqrt((math.pow((math.pi * (n * 2.0)), (1.0 - k)) / k)) return tmp
function code(k, n) tmp = 0.0 if (k <= 4.3e-65) tmp = Float64(sqrt(Float64(pi / k)) * sqrt(Float64(n * 2.0))); else tmp = sqrt(Float64((Float64(pi * Float64(n * 2.0)) ^ Float64(1.0 - k)) / k)); end return tmp end
function tmp_2 = code(k, n) tmp = 0.0; if (k <= 4.3e-65) tmp = sqrt((pi / k)) * sqrt((n * 2.0)); else tmp = sqrt((((pi * (n * 2.0)) ^ (1.0 - k)) / k)); end tmp_2 = tmp; end
code[k_, n_] := If[LessEqual[k, 4.3e-65], N[(N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(n * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[Power[N[(Pi * N[(n * 2.0), $MachinePrecision]), $MachinePrecision], N[(1.0 - k), $MachinePrecision]], $MachinePrecision] / k), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;k \leq 4.3 \cdot 10^{-65}:\\
\;\;\;\;\sqrt{\frac{\pi}{k}} \cdot \sqrt{n \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{{\left(\pi \cdot \left(n \cdot 2\right)\right)}^{\left(1 - k\right)}}{k}}\\
\end{array}
\end{array}
if k < 4.30000000000000024e-65Initial program 98.2%
Taylor expanded in k around 0 68.6%
*-commutative68.6%
associate-/l*68.6%
Simplified68.6%
sqrt-unprod68.8%
associate-*r/68.8%
*-commutative68.8%
Applied egg-rr68.8%
Taylor expanded in n around 0 68.8%
associate-*r/68.8%
Simplified68.8%
associate-*r*68.8%
*-commutative68.8%
sqrt-prod99.3%
*-commutative99.3%
Applied egg-rr99.3%
*-commutative99.3%
Simplified99.3%
if 4.30000000000000024e-65 < k Initial program 99.5%
add-sqr-sqrt99.5%
sqrt-unprod99.5%
*-commutative99.5%
associate-*r*99.5%
div-sub99.5%
metadata-eval99.5%
div-inv99.5%
*-commutative99.5%
Applied egg-rr99.6%
Simplified99.6%
Final simplification99.5%
(FPCore (k n) :precision binary64 (* (sqrt (/ PI k)) (/ (sqrt (* n 2.0)) (pow (sqrt (* PI (* n 2.0))) k))))
double code(double k, double n) {
return sqrt((((double) M_PI) / k)) * (sqrt((n * 2.0)) / pow(sqrt((((double) M_PI) * (n * 2.0))), k));
}
public static double code(double k, double n) {
return Math.sqrt((Math.PI / k)) * (Math.sqrt((n * 2.0)) / Math.pow(Math.sqrt((Math.PI * (n * 2.0))), k));
}
def code(k, n): return math.sqrt((math.pi / k)) * (math.sqrt((n * 2.0)) / math.pow(math.sqrt((math.pi * (n * 2.0))), k))
function code(k, n) return Float64(sqrt(Float64(pi / k)) * Float64(sqrt(Float64(n * 2.0)) / (sqrt(Float64(pi * Float64(n * 2.0))) ^ k))) end
function tmp = code(k, n) tmp = sqrt((pi / k)) * (sqrt((n * 2.0)) / (sqrt((pi * (n * 2.0))) ^ k)); end
code[k_, n_] := N[(N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision] * N[(N[Sqrt[N[(n * 2.0), $MachinePrecision]], $MachinePrecision] / N[Power[N[Sqrt[N[(Pi * N[(n * 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], k], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\frac{\pi}{k}} \cdot \frac{\sqrt{n \cdot 2}}{{\left(\sqrt{\pi \cdot \left(n \cdot 2\right)}\right)}^{k}}
\end{array}
Initial program 99.0%
associate-*l/99.1%
*-un-lft-identity99.1%
associate-*r*99.1%
div-sub99.1%
metadata-eval99.1%
pow-div99.3%
pow1/299.3%
associate-/l/99.3%
div-inv99.3%
metadata-eval99.3%
Applied egg-rr99.3%
*-commutative99.3%
associate-*l*99.3%
*-commutative99.3%
*-commutative99.3%
associate-*l*99.3%
*-commutative99.3%
Simplified99.3%
sqrt-prod99.1%
*-commutative99.1%
times-frac99.1%
sqrt-div99.3%
pow-unpow99.3%
pow1/299.3%
Applied egg-rr99.3%
Final simplification99.3%
(FPCore (k n) :precision binary64 (let* ((t_0 (* PI (* n 2.0)))) (/ (sqrt t_0) (sqrt (* k (pow t_0 k))))))
double code(double k, double n) {
double t_0 = ((double) M_PI) * (n * 2.0);
return sqrt(t_0) / sqrt((k * pow(t_0, k)));
}
public static double code(double k, double n) {
double t_0 = Math.PI * (n * 2.0);
return Math.sqrt(t_0) / Math.sqrt((k * Math.pow(t_0, k)));
}
def code(k, n): t_0 = math.pi * (n * 2.0) return math.sqrt(t_0) / math.sqrt((k * math.pow(t_0, k)))
function code(k, n) t_0 = Float64(pi * Float64(n * 2.0)) return Float64(sqrt(t_0) / sqrt(Float64(k * (t_0 ^ k)))) end
function tmp = code(k, n) t_0 = pi * (n * 2.0); tmp = sqrt(t_0) / sqrt((k * (t_0 ^ k))); end
code[k_, n_] := Block[{t$95$0 = N[(Pi * N[(n * 2.0), $MachinePrecision]), $MachinePrecision]}, N[(N[Sqrt[t$95$0], $MachinePrecision] / N[Sqrt[N[(k * N[Power[t$95$0, k], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \pi \cdot \left(n \cdot 2\right)\\
\frac{\sqrt{t\_0}}{\sqrt{k \cdot {t\_0}^{k}}}
\end{array}
\end{array}
Initial program 99.0%
associate-*l/99.1%
*-un-lft-identity99.1%
associate-*r*99.1%
div-sub99.1%
metadata-eval99.1%
pow-div99.3%
pow1/299.3%
associate-/l/99.3%
div-inv99.3%
metadata-eval99.3%
Applied egg-rr99.3%
*-commutative99.3%
associate-*l*99.3%
*-commutative99.3%
*-commutative99.3%
associate-*l*99.3%
*-commutative99.3%
Simplified99.3%
div-inv99.1%
add-sqr-sqrt99.0%
sqrt-unprod99.1%
*-commutative99.1%
*-commutative99.1%
swap-sqr99.1%
add-sqr-sqrt99.1%
pow-unpow99.1%
pow1/299.1%
Applied egg-rr99.2%
associate-*r/99.3%
*-rgt-identity99.3%
Simplified99.3%
Final simplification99.3%
(FPCore (k n) :precision binary64 (if (<= k 7.6e+93) (* (sqrt (/ PI k)) (sqrt (* n 2.0))) (sqrt (* 2.0 (+ -1.0 (fma n (/ PI k) 1.0))))))
double code(double k, double n) {
double tmp;
if (k <= 7.6e+93) {
tmp = sqrt((((double) M_PI) / k)) * sqrt((n * 2.0));
} else {
tmp = sqrt((2.0 * (-1.0 + fma(n, (((double) M_PI) / k), 1.0))));
}
return tmp;
}
function code(k, n) tmp = 0.0 if (k <= 7.6e+93) tmp = Float64(sqrt(Float64(pi / k)) * sqrt(Float64(n * 2.0))); else tmp = sqrt(Float64(2.0 * Float64(-1.0 + fma(n, Float64(pi / k), 1.0)))); end return tmp end
code[k_, n_] := If[LessEqual[k, 7.6e+93], N[(N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(n * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(2.0 * N[(-1.0 + N[(n * N[(Pi / k), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;k \leq 7.6 \cdot 10^{+93}:\\
\;\;\;\;\sqrt{\frac{\pi}{k}} \cdot \sqrt{n \cdot 2}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{2 \cdot \left(-1 + \mathsf{fma}\left(n, \frac{\pi}{k}, 1\right)\right)}\\
\end{array}
\end{array}
if k < 7.5999999999999996e93Initial program 98.5%
Taylor expanded in k around 0 59.2%
*-commutative59.2%
associate-/l*59.2%
Simplified59.2%
sqrt-unprod59.4%
associate-*r/59.4%
*-commutative59.4%
Applied egg-rr59.4%
Taylor expanded in n around 0 59.4%
associate-*r/59.4%
Simplified59.4%
associate-*r*59.4%
*-commutative59.4%
sqrt-prod77.2%
*-commutative77.2%
Applied egg-rr77.2%
*-commutative77.2%
Simplified77.2%
if 7.5999999999999996e93 < k Initial program 100.0%
Taylor expanded in k around 0 2.6%
*-commutative2.6%
associate-/l*2.6%
Simplified2.6%
sqrt-unprod2.6%
associate-*r/2.6%
*-commutative2.6%
Applied egg-rr2.6%
Taylor expanded in n around 0 2.6%
associate-*r/2.6%
Simplified2.6%
associate-*r/2.6%
*-commutative2.6%
associate-*r/2.6%
expm1-log1p-u2.6%
expm1-undefine28.8%
clear-num28.8%
un-div-inv28.8%
Applied egg-rr28.8%
sub-neg28.8%
metadata-eval28.8%
+-commutative28.8%
log1p-undefine28.8%
rem-exp-log28.8%
+-commutative28.8%
associate-/r/28.8%
*-commutative28.8%
fma-define28.8%
Simplified28.8%
Final simplification61.3%
(FPCore (k n) :precision binary64 (/ (pow (* 2.0 (* PI n)) (- 0.5 (/ k 2.0))) (sqrt k)))
double code(double k, double n) {
return pow((2.0 * (((double) M_PI) * n)), (0.5 - (k / 2.0))) / sqrt(k);
}
public static double code(double k, double n) {
return Math.pow((2.0 * (Math.PI * n)), (0.5 - (k / 2.0))) / Math.sqrt(k);
}
def code(k, n): return math.pow((2.0 * (math.pi * n)), (0.5 - (k / 2.0))) / math.sqrt(k)
function code(k, n) return Float64((Float64(2.0 * Float64(pi * n)) ^ Float64(0.5 - Float64(k / 2.0))) / sqrt(k)) end
function tmp = code(k, n) tmp = ((2.0 * (pi * n)) ^ (0.5 - (k / 2.0))) / sqrt(k); end
code[k_, n_] := N[(N[Power[N[(2.0 * N[(Pi * n), $MachinePrecision]), $MachinePrecision], N[(0.5 - N[(k / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(0.5 - \frac{k}{2}\right)}}{\sqrt{k}}
\end{array}
Initial program 99.0%
associate-*l/99.1%
*-lft-identity99.1%
associate-*l*99.1%
div-sub99.1%
metadata-eval99.1%
Simplified99.1%
Final simplification99.1%
(FPCore (k n) :precision binary64 (* (sqrt (/ PI k)) (sqrt (* n 2.0))))
double code(double k, double n) {
return sqrt((((double) M_PI) / k)) * sqrt((n * 2.0));
}
public static double code(double k, double n) {
return Math.sqrt((Math.PI / k)) * Math.sqrt((n * 2.0));
}
def code(k, n): return math.sqrt((math.pi / k)) * math.sqrt((n * 2.0))
function code(k, n) return Float64(sqrt(Float64(pi / k)) * sqrt(Float64(n * 2.0))) end
function tmp = code(k, n) tmp = sqrt((pi / k)) * sqrt((n * 2.0)); end
code[k_, n_] := N[(N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(n * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\frac{\pi}{k}} \cdot \sqrt{n \cdot 2}
\end{array}
Initial program 99.0%
Taylor expanded in k around 0 40.6%
*-commutative40.6%
associate-/l*40.6%
Simplified40.6%
sqrt-unprod40.8%
associate-*r/40.8%
*-commutative40.8%
Applied egg-rr40.8%
Taylor expanded in n around 0 40.8%
associate-*r/40.8%
Simplified40.8%
associate-*r*40.8%
*-commutative40.8%
sqrt-prod52.7%
*-commutative52.7%
Applied egg-rr52.7%
*-commutative52.7%
Simplified52.7%
Final simplification52.7%
(FPCore (k n) :precision binary64 (pow (/ k (* PI (* n 2.0))) -0.5))
double code(double k, double n) {
return pow((k / (((double) M_PI) * (n * 2.0))), -0.5);
}
public static double code(double k, double n) {
return Math.pow((k / (Math.PI * (n * 2.0))), -0.5);
}
def code(k, n): return math.pow((k / (math.pi * (n * 2.0))), -0.5)
function code(k, n) return Float64(k / Float64(pi * Float64(n * 2.0))) ^ -0.5 end
function tmp = code(k, n) tmp = (k / (pi * (n * 2.0))) ^ -0.5; end
code[k_, n_] := N[Power[N[(k / N[(Pi * N[(n * 2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -0.5], $MachinePrecision]
\begin{array}{l}
\\
{\left(\frac{k}{\pi \cdot \left(n \cdot 2\right)}\right)}^{-0.5}
\end{array}
Initial program 99.0%
Taylor expanded in k around 0 40.6%
*-commutative40.6%
associate-/l*40.6%
Simplified40.6%
sqrt-unprod40.8%
associate-*r/40.8%
*-commutative40.8%
Applied egg-rr40.8%
*-commutative40.8%
sqrt-prod40.6%
clear-num40.6%
*-commutative40.6%
sqrt-div40.9%
metadata-eval40.9%
associate-/r/40.9%
inv-pow40.9%
sqrt-undiv41.0%
sqrt-pow241.1%
*-commutative41.1%
metadata-eval41.1%
Applied egg-rr41.1%
associate-/r*41.1%
associate-*r*41.1%
Simplified41.1%
Final simplification41.1%
(FPCore (k n) :precision binary64 (sqrt (* 2.0 (* (/ PI k) n))))
double code(double k, double n) {
return sqrt((2.0 * ((((double) M_PI) / k) * n)));
}
public static double code(double k, double n) {
return Math.sqrt((2.0 * ((Math.PI / k) * n)));
}
def code(k, n): return math.sqrt((2.0 * ((math.pi / k) * n)))
function code(k, n) return sqrt(Float64(2.0 * Float64(Float64(pi / k) * n))) end
function tmp = code(k, n) tmp = sqrt((2.0 * ((pi / k) * n))); end
code[k_, n_] := N[Sqrt[N[(2.0 * N[(N[(Pi / k), $MachinePrecision] * n), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2 \cdot \left(\frac{\pi}{k} \cdot n\right)}
\end{array}
Initial program 99.0%
Taylor expanded in k around 0 40.6%
*-commutative40.6%
associate-/l*40.6%
Simplified40.6%
sqrt-unprod40.8%
associate-*r/40.8%
*-commutative40.8%
Applied egg-rr40.8%
Taylor expanded in n around 0 40.8%
associate-*r/40.8%
Simplified40.8%
Final simplification40.8%
herbie shell --seed 2024051
(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))))