
(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 6 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 (let* ((t_0 (* (* 2.0 n) PI))) (/ (sqrt t_0) (* (pow t_0 (* 0.5 k)) (sqrt k)))))
double code(double k, double n) {
double t_0 = (2.0 * n) * ((double) M_PI);
return sqrt(t_0) / (pow(t_0, (0.5 * k)) * sqrt(k));
}
public static double code(double k, double n) {
double t_0 = (2.0 * n) * Math.PI;
return Math.sqrt(t_0) / (Math.pow(t_0, (0.5 * k)) * Math.sqrt(k));
}
def code(k, n): t_0 = (2.0 * n) * math.pi return math.sqrt(t_0) / (math.pow(t_0, (0.5 * k)) * math.sqrt(k))
function code(k, n) t_0 = Float64(Float64(2.0 * n) * pi) return Float64(sqrt(t_0) / Float64((t_0 ^ Float64(0.5 * k)) * sqrt(k))) end
function tmp = code(k, n) t_0 = (2.0 * n) * pi; tmp = sqrt(t_0) / ((t_0 ^ (0.5 * k)) * sqrt(k)); end
code[k_, n_] := Block[{t$95$0 = N[(N[(2.0 * n), $MachinePrecision] * Pi), $MachinePrecision]}, N[(N[Sqrt[t$95$0], $MachinePrecision] / N[(N[Power[t$95$0, N[(0.5 * k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[k], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(2 \cdot n\right) \cdot \pi\\
\frac{\sqrt{t_0}}{{t_0}^{\left(0.5 \cdot k\right)} \cdot \sqrt{k}}
\end{array}
\end{array}
Initial program 99.4%
unpow-prod-down75.3%
unpow-prod-down99.4%
div-sub99.4%
metadata-eval99.4%
pow-sub99.6%
pow1/299.6%
frac-times99.7%
*-un-lft-identity99.7%
associate-*l*99.7%
associate-*l*99.7%
div-inv99.7%
metadata-eval99.7%
Applied egg-rr99.7%
*-commutative99.7%
*-commutative99.7%
associate-*r*99.7%
*-commutative99.7%
associate-*r*99.7%
*-commutative99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (k n) :precision binary64 (/ (pow (* n (* 2.0 PI)) (- 0.5 (/ k 2.0))) (sqrt k)))
double code(double k, double n) {
return pow((n * (2.0 * ((double) M_PI))), (0.5 - (k / 2.0))) / sqrt(k);
}
public static double code(double k, double n) {
return Math.pow((n * (2.0 * Math.PI)), (0.5 - (k / 2.0))) / Math.sqrt(k);
}
def code(k, n): return math.pow((n * (2.0 * math.pi)), (0.5 - (k / 2.0))) / math.sqrt(k)
function code(k, n) return Float64((Float64(n * Float64(2.0 * pi)) ^ Float64(0.5 - Float64(k / 2.0))) / sqrt(k)) end
function tmp = code(k, n) tmp = ((n * (2.0 * pi)) ^ (0.5 - (k / 2.0))) / sqrt(k); end
code[k_, n_] := N[(N[Power[N[(n * N[(2.0 * Pi), $MachinePrecision]), $MachinePrecision], N[(0.5 - N[(k / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{{\left(n \cdot \left(2 \cdot \pi\right)\right)}^{\left(0.5 - \frac{k}{2}\right)}}{\sqrt{k}}
\end{array}
Initial program 99.4%
associate-*l/99.4%
*-lft-identity99.4%
sqr-pow99.2%
pow-sqr99.4%
*-commutative99.4%
associate-*l/99.4%
associate-/l*99.4%
metadata-eval99.4%
/-rgt-identity99.4%
div-sub99.4%
metadata-eval99.4%
Simplified99.4%
Final simplification99.4%
(FPCore (k n) :precision binary64 (pow (/ k (pow (* 2.0 (* n PI)) (- 1.0 k))) -0.5))
double code(double k, double n) {
return pow((k / pow((2.0 * (n * ((double) M_PI))), (1.0 - k))), -0.5);
}
public static double code(double k, double n) {
return Math.pow((k / Math.pow((2.0 * (n * Math.PI)), (1.0 - k))), -0.5);
}
def code(k, n): return math.pow((k / math.pow((2.0 * (n * math.pi)), (1.0 - k))), -0.5)
function code(k, n) return Float64(k / (Float64(2.0 * Float64(n * pi)) ^ Float64(1.0 - k))) ^ -0.5 end
function tmp = code(k, n) tmp = (k / ((2.0 * (n * pi)) ^ (1.0 - k))) ^ -0.5; end
code[k_, n_] := N[Power[N[(k / N[Power[N[(2.0 * N[(n * Pi), $MachinePrecision]), $MachinePrecision], N[(1.0 - k), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], -0.5], $MachinePrecision]
\begin{array}{l}
\\
{\left(\frac{k}{{\left(2 \cdot \left(n \cdot \pi\right)\right)}^{\left(1 - k\right)}}\right)}^{-0.5}
\end{array}
Initial program 99.4%
*-commutative99.4%
div-sub99.4%
metadata-eval99.4%
div-inv99.4%
expm1-log1p-u96.3%
expm1-udef83.4%
Applied egg-rr69.5%
expm1-def82.6%
expm1-log1p84.1%
*-commutative84.1%
associate-*r*84.1%
Simplified84.1%
clear-num84.1%
sqrt-div85.6%
metadata-eval85.6%
*-commutative85.6%
Applied egg-rr85.6%
pow1/285.6%
pow-flip85.7%
associate-*r*85.7%
*-commutative85.7%
associate-*r*85.7%
metadata-eval85.7%
Applied egg-rr85.7%
Final simplification85.7%
(FPCore (k n) :precision binary64 (sqrt (/ (pow (* (* 2.0 n) PI) (- 1.0 k)) k)))
double code(double k, double n) {
return sqrt((pow(((2.0 * n) * ((double) M_PI)), (1.0 - k)) / k));
}
public static double code(double k, double n) {
return Math.sqrt((Math.pow(((2.0 * n) * Math.PI), (1.0 - k)) / k));
}
def code(k, n): return math.sqrt((math.pow(((2.0 * n) * math.pi), (1.0 - k)) / k))
function code(k, n) return sqrt(Float64((Float64(Float64(2.0 * n) * pi) ^ Float64(1.0 - k)) / k)) end
function tmp = code(k, n) tmp = sqrt(((((2.0 * n) * pi) ^ (1.0 - k)) / k)); end
code[k_, n_] := N[Sqrt[N[(N[Power[N[(N[(2.0 * n), $MachinePrecision] * Pi), $MachinePrecision], N[(1.0 - k), $MachinePrecision]], $MachinePrecision] / k), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\frac{{\left(\left(2 \cdot n\right) \cdot \pi\right)}^{\left(1 - k\right)}}{k}}
\end{array}
Initial program 99.4%
*-commutative99.4%
div-sub99.4%
metadata-eval99.4%
div-inv99.4%
expm1-log1p-u96.3%
expm1-udef83.4%
Applied egg-rr69.5%
expm1-def82.6%
expm1-log1p84.1%
*-commutative84.1%
associate-*r*84.1%
Simplified84.1%
Final simplification84.1%
(FPCore (k n) :precision binary64 (/ 1.0 (sqrt (/ k (* 2.0 (* n PI))))))
double code(double k, double n) {
return 1.0 / sqrt((k / (2.0 * (n * ((double) M_PI)))));
}
public static double code(double k, double n) {
return 1.0 / Math.sqrt((k / (2.0 * (n * Math.PI))));
}
def code(k, n): return 1.0 / math.sqrt((k / (2.0 * (n * math.pi))))
function code(k, n) return Float64(1.0 / sqrt(Float64(k / Float64(2.0 * Float64(n * pi))))) end
function tmp = code(k, n) tmp = 1.0 / sqrt((k / (2.0 * (n * pi)))); end
code[k_, n_] := N[(1.0 / N[Sqrt[N[(k / N[(2.0 * N[(n * Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\sqrt{\frac{k}{2 \cdot \left(n \cdot \pi\right)}}}
\end{array}
Initial program 99.4%
*-commutative99.4%
div-sub99.4%
metadata-eval99.4%
div-inv99.4%
expm1-log1p-u96.3%
expm1-udef83.4%
Applied egg-rr69.5%
expm1-def82.6%
expm1-log1p84.1%
*-commutative84.1%
associate-*r*84.1%
Simplified84.1%
clear-num84.1%
sqrt-div85.6%
metadata-eval85.6%
*-commutative85.6%
Applied egg-rr85.6%
Taylor expanded in k around 0 39.6%
Final simplification39.6%
(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(2.0 * Float64(pi * Float64(n / k)))) end
function tmp = code(k, n) tmp = sqrt((2.0 * (pi * (n / k)))); end
code[k_, n_] := N[Sqrt[N[(2.0 * N[(Pi * N[(n / k), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2 \cdot \left(\pi \cdot \frac{n}{k}\right)}
\end{array}
Initial program 99.4%
*-commutative99.4%
div-sub99.4%
metadata-eval99.4%
div-inv99.4%
expm1-log1p-u96.3%
expm1-udef83.4%
Applied egg-rr69.5%
expm1-def82.6%
expm1-log1p84.1%
*-commutative84.1%
associate-*r*84.1%
Simplified84.1%
pow-sub84.4%
pow184.4%
*-commutative84.4%
*-commutative84.4%
Applied egg-rr84.4%
Taylor expanded in k around 0 38.1%
associate-/l*38.1%
Simplified38.1%
associate-/r/38.2%
Applied egg-rr38.2%
Final simplification38.2%
herbie shell --seed 2023292
(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))))