
(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 4e-48) (/ (sqrt (* PI (* 2.0 n))) (sqrt k)) (sqrt (* (pow (* 2.0 (* PI n)) (- 1.0 k)) (/ 1.0 k)))))
double code(double k, double n) {
double tmp;
if (k <= 4e-48) {
tmp = sqrt((((double) M_PI) * (2.0 * n))) / sqrt(k);
} else {
tmp = sqrt((pow((2.0 * (((double) M_PI) * n)), (1.0 - k)) * (1.0 / k)));
}
return tmp;
}
public static double code(double k, double n) {
double tmp;
if (k <= 4e-48) {
tmp = Math.sqrt((Math.PI * (2.0 * n))) / Math.sqrt(k);
} else {
tmp = Math.sqrt((Math.pow((2.0 * (Math.PI * n)), (1.0 - k)) * (1.0 / k)));
}
return tmp;
}
def code(k, n): tmp = 0 if k <= 4e-48: tmp = math.sqrt((math.pi * (2.0 * n))) / math.sqrt(k) else: tmp = math.sqrt((math.pow((2.0 * (math.pi * n)), (1.0 - k)) * (1.0 / k))) return tmp
function code(k, n) tmp = 0.0 if (k <= 4e-48) tmp = Float64(sqrt(Float64(pi * Float64(2.0 * n))) / sqrt(k)); else tmp = sqrt(Float64((Float64(2.0 * Float64(pi * n)) ^ Float64(1.0 - k)) * Float64(1.0 / k))); end return tmp end
function tmp_2 = code(k, n) tmp = 0.0; if (k <= 4e-48) tmp = sqrt((pi * (2.0 * n))) / sqrt(k); else tmp = sqrt((((2.0 * (pi * n)) ^ (1.0 - k)) * (1.0 / k))); end tmp_2 = tmp; end
code[k_, n_] := If[LessEqual[k, 4e-48], N[(N[Sqrt[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[Power[N[(2.0 * N[(Pi * n), $MachinePrecision]), $MachinePrecision], N[(1.0 - k), $MachinePrecision]], $MachinePrecision] * N[(1.0 / k), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;k \leq 4 \cdot 10^{-48}:\\
\;\;\;\;\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\sqrt{k}}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{{\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(1 - k\right)} \cdot \frac{1}{k}}\\
\end{array}
\end{array}
if k < 3.9999999999999999e-48Initial program 99.3%
*-commutative99.3%
*-commutative99.3%
associate-*r*99.3%
div-inv99.5%
expm1-log1p-u93.2%
expm1-udef77.0%
Applied egg-rr47.2%
expm1-def63.4%
expm1-log1p66.3%
associate-*r*66.3%
Simplified66.3%
Taylor expanded in k around 0 66.3%
associate-/l*66.4%
associate-/r/66.4%
Simplified66.4%
expm1-log1p-u63.5%
expm1-udef47.2%
*-commutative47.2%
Applied egg-rr47.2%
expm1-def63.5%
expm1-log1p66.4%
associate-*r/66.3%
*-commutative66.3%
associate-*r/66.3%
Simplified66.3%
sqrt-div99.5%
associate-*r*99.5%
Applied egg-rr99.5%
if 3.9999999999999999e-48 < k Initial program 99.8%
*-commutative99.8%
*-commutative99.8%
associate-*r*99.8%
div-inv99.8%
expm1-log1p-u99.3%
expm1-udef93.5%
Applied egg-rr93.5%
expm1-def99.3%
expm1-log1p99.8%
associate-*r*99.8%
Simplified99.8%
div-inv99.8%
associate-*r*99.8%
Applied egg-rr99.8%
Final simplification99.7%
(FPCore (k n) :precision binary64 (if (<= k 4e-48) (/ (sqrt (* PI (* 2.0 n))) (sqrt k)) (sqrt (/ (pow (* n (* PI 2.0)) (- 1.0 k)) k))))
double code(double k, double n) {
double tmp;
if (k <= 4e-48) {
tmp = sqrt((((double) M_PI) * (2.0 * n))) / sqrt(k);
} else {
tmp = sqrt((pow((n * (((double) M_PI) * 2.0)), (1.0 - k)) / k));
}
return tmp;
}
public static double code(double k, double n) {
double tmp;
if (k <= 4e-48) {
tmp = Math.sqrt((Math.PI * (2.0 * n))) / Math.sqrt(k);
} else {
tmp = Math.sqrt((Math.pow((n * (Math.PI * 2.0)), (1.0 - k)) / k));
}
return tmp;
}
def code(k, n): tmp = 0 if k <= 4e-48: tmp = math.sqrt((math.pi * (2.0 * n))) / math.sqrt(k) else: tmp = math.sqrt((math.pow((n * (math.pi * 2.0)), (1.0 - k)) / k)) return tmp
function code(k, n) tmp = 0.0 if (k <= 4e-48) tmp = Float64(sqrt(Float64(pi * Float64(2.0 * n))) / sqrt(k)); else tmp = sqrt(Float64((Float64(n * Float64(pi * 2.0)) ^ Float64(1.0 - k)) / k)); end return tmp end
function tmp_2 = code(k, n) tmp = 0.0; if (k <= 4e-48) tmp = sqrt((pi * (2.0 * n))) / sqrt(k); else tmp = sqrt((((n * (pi * 2.0)) ^ (1.0 - k)) / k)); end tmp_2 = tmp; end
code[k_, n_] := If[LessEqual[k, 4e-48], N[(N[Sqrt[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[Power[N[(n * N[(Pi * 2.0), $MachinePrecision]), $MachinePrecision], N[(1.0 - k), $MachinePrecision]], $MachinePrecision] / k), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;k \leq 4 \cdot 10^{-48}:\\
\;\;\;\;\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\sqrt{k}}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{{\left(n \cdot \left(\pi \cdot 2\right)\right)}^{\left(1 - k\right)}}{k}}\\
\end{array}
\end{array}
if k < 3.9999999999999999e-48Initial program 99.3%
*-commutative99.3%
*-commutative99.3%
associate-*r*99.3%
div-inv99.5%
expm1-log1p-u93.2%
expm1-udef77.0%
Applied egg-rr47.2%
expm1-def63.4%
expm1-log1p66.3%
associate-*r*66.3%
Simplified66.3%
Taylor expanded in k around 0 66.3%
associate-/l*66.4%
associate-/r/66.4%
Simplified66.4%
expm1-log1p-u63.5%
expm1-udef47.2%
*-commutative47.2%
Applied egg-rr47.2%
expm1-def63.5%
expm1-log1p66.4%
associate-*r/66.3%
*-commutative66.3%
associate-*r/66.3%
Simplified66.3%
sqrt-div99.5%
associate-*r*99.5%
Applied egg-rr99.5%
if 3.9999999999999999e-48 < k Initial program 99.8%
*-commutative99.8%
*-commutative99.8%
associate-*r*99.8%
div-inv99.8%
expm1-log1p-u99.3%
expm1-udef93.5%
Applied egg-rr93.5%
expm1-def99.3%
expm1-log1p99.8%
associate-*r*99.8%
Simplified99.8%
Final simplification99.7%
(FPCore (k n) :precision binary64 (/ (pow (* PI (* 2.0 n)) (/ (- 1.0 k) 2.0)) (sqrt k)))
double code(double k, double n) {
return pow((((double) M_PI) * (2.0 * n)), ((1.0 - k) / 2.0)) / sqrt(k);
}
public static double code(double k, double n) {
return Math.pow((Math.PI * (2.0 * n)), ((1.0 - k) / 2.0)) / Math.sqrt(k);
}
def code(k, n): return math.pow((math.pi * (2.0 * n)), ((1.0 - k) / 2.0)) / math.sqrt(k)
function code(k, n) return Float64((Float64(pi * Float64(2.0 * n)) ^ Float64(Float64(1.0 - k) / 2.0)) / sqrt(k)) end
function tmp = code(k, n) tmp = ((pi * (2.0 * n)) ^ ((1.0 - k) / 2.0)) / sqrt(k); end
code[k_, n_] := N[(N[Power[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}
\end{array}
Initial program 99.6%
associate-*l/99.7%
*-lft-identity99.7%
*-commutative99.7%
associate-*l*99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (k n) :precision binary64 (/ (sqrt 2.0) (sqrt (/ (/ k PI) n))))
double code(double k, double n) {
return sqrt(2.0) / sqrt(((k / ((double) M_PI)) / n));
}
public static double code(double k, double n) {
return Math.sqrt(2.0) / Math.sqrt(((k / Math.PI) / n));
}
def code(k, n): return math.sqrt(2.0) / math.sqrt(((k / math.pi) / n))
function code(k, n) return Float64(sqrt(2.0) / sqrt(Float64(Float64(k / pi) / n))) end
function tmp = code(k, n) tmp = sqrt(2.0) / sqrt(((k / pi) / n)); end
code[k_, n_] := N[(N[Sqrt[2.0], $MachinePrecision] / N[Sqrt[N[(N[(k / Pi), $MachinePrecision] / n), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sqrt{2}}{\sqrt{\frac{\frac{k}{\pi}}{n}}}
\end{array}
Initial program 99.6%
*-commutative99.6%
*-commutative99.6%
associate-*r*99.6%
div-inv99.7%
expm1-log1p-u96.7%
expm1-udef86.4%
Applied egg-rr73.6%
expm1-def83.9%
expm1-log1p85.4%
associate-*r*85.4%
Simplified85.4%
Taylor expanded in k around 0 36.8%
associate-/l*36.8%
associate-/r/36.8%
Simplified36.8%
expm1-log1p-u35.3%
expm1-udef34.9%
*-commutative34.9%
Applied egg-rr34.9%
expm1-def35.3%
expm1-log1p36.8%
associate-*r/36.8%
*-commutative36.8%
associate-*r/36.8%
Simplified36.8%
associate-/l*36.8%
sqrt-div36.9%
*-commutative36.9%
Applied egg-rr36.9%
associate-/r*36.9%
Simplified36.9%
Final simplification36.9%
(FPCore (k n) :precision binary64 (/ (sqrt (* PI (* 2.0 n))) (sqrt k)))
double code(double k, double n) {
return sqrt((((double) M_PI) * (2.0 * n))) / sqrt(k);
}
public static double code(double k, double n) {
return Math.sqrt((Math.PI * (2.0 * n))) / Math.sqrt(k);
}
def code(k, n): return math.sqrt((math.pi * (2.0 * n))) / math.sqrt(k)
function code(k, n) return Float64(sqrt(Float64(pi * Float64(2.0 * n))) / sqrt(k)) end
function tmp = code(k, n) tmp = sqrt((pi * (2.0 * n))) / sqrt(k); end
code[k_, n_] := N[(N[Sqrt[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\sqrt{k}}
\end{array}
Initial program 99.6%
*-commutative99.6%
*-commutative99.6%
associate-*r*99.6%
div-inv99.7%
expm1-log1p-u96.7%
expm1-udef86.4%
Applied egg-rr73.6%
expm1-def83.9%
expm1-log1p85.4%
associate-*r*85.4%
Simplified85.4%
Taylor expanded in k around 0 36.8%
associate-/l*36.8%
associate-/r/36.8%
Simplified36.8%
expm1-log1p-u35.3%
expm1-udef34.9%
*-commutative34.9%
Applied egg-rr34.9%
expm1-def35.3%
expm1-log1p36.8%
associate-*r/36.8%
*-commutative36.8%
associate-*r/36.8%
Simplified36.8%
sqrt-div51.0%
associate-*r*51.0%
Applied egg-rr51.0%
Final simplification51.0%
(FPCore (k n) :precision binary64 (/ 1.0 (sqrt (* (/ 0.5 PI) (/ k n)))))
double code(double k, double n) {
return 1.0 / sqrt(((0.5 / ((double) M_PI)) * (k / n)));
}
public static double code(double k, double n) {
return 1.0 / Math.sqrt(((0.5 / Math.PI) * (k / n)));
}
def code(k, n): return 1.0 / math.sqrt(((0.5 / math.pi) * (k / n)))
function code(k, n) return Float64(1.0 / sqrt(Float64(Float64(0.5 / pi) * Float64(k / n)))) end
function tmp = code(k, n) tmp = 1.0 / sqrt(((0.5 / pi) * (k / n))); end
code[k_, n_] := N[(1.0 / N[Sqrt[N[(N[(0.5 / Pi), $MachinePrecision] * N[(k / n), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\sqrt{\frac{0.5}{\pi} \cdot \frac{k}{n}}}
\end{array}
Initial program 99.6%
*-commutative99.6%
associate-*r*99.6%
associate-/r/99.6%
add-sqr-sqrt99.3%
sqrt-unprod99.6%
associate-*r*99.6%
*-commutative99.6%
associate-*r*99.6%
*-commutative99.6%
pow-prod-up99.6%
Applied egg-rr99.6%
Taylor expanded in n around 0 82.8%
distribute-lft-in82.8%
remove-double-neg82.8%
log-rec82.8%
mul-1-neg82.8%
distribute-lft-in82.8%
*-commutative82.8%
exp-prod82.8%
Simplified85.6%
Taylor expanded in k around 0 36.9%
associate-*r/36.9%
*-commutative36.9%
times-frac36.9%
Simplified36.9%
Final simplification36.9%
(FPCore (k n) :precision binary64 (/ 1.0 (sqrt (/ (* k 0.5) (* PI n)))))
double code(double k, double n) {
return 1.0 / sqrt(((k * 0.5) / (((double) M_PI) * n)));
}
public static double code(double k, double n) {
return 1.0 / Math.sqrt(((k * 0.5) / (Math.PI * n)));
}
def code(k, n): return 1.0 / math.sqrt(((k * 0.5) / (math.pi * n)))
function code(k, n) return Float64(1.0 / sqrt(Float64(Float64(k * 0.5) / Float64(pi * n)))) end
function tmp = code(k, n) tmp = 1.0 / sqrt(((k * 0.5) / (pi * n))); end
code[k_, n_] := N[(1.0 / N[Sqrt[N[(N[(k * 0.5), $MachinePrecision] / N[(Pi * n), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\sqrt{\frac{k \cdot 0.5}{\pi \cdot n}}}
\end{array}
Initial program 99.6%
*-commutative99.6%
associate-*r*99.6%
associate-/r/99.6%
add-sqr-sqrt99.3%
sqrt-unprod99.6%
associate-*r*99.6%
*-commutative99.6%
associate-*r*99.6%
*-commutative99.6%
pow-prod-up99.6%
Applied egg-rr99.6%
Taylor expanded in n around 0 82.8%
distribute-lft-in82.8%
remove-double-neg82.8%
log-rec82.8%
mul-1-neg82.8%
distribute-lft-in82.8%
*-commutative82.8%
exp-prod82.8%
Simplified85.6%
Taylor expanded in k around 0 36.9%
associate-*r/36.9%
Simplified36.9%
Final simplification36.9%
(FPCore (k n) :precision binary64 (sqrt (* 2.0 (* n (/ PI k)))))
double code(double k, double n) {
return sqrt((2.0 * (n * (((double) M_PI) / k))));
}
public static double code(double k, double n) {
return Math.sqrt((2.0 * (n * (Math.PI / k))));
}
def code(k, n): return math.sqrt((2.0 * (n * (math.pi / k))))
function code(k, n) return sqrt(Float64(2.0 * Float64(n * Float64(pi / k)))) end
function tmp = code(k, n) tmp = sqrt((2.0 * (n * (pi / k)))); end
code[k_, n_] := N[Sqrt[N[(2.0 * N[(n * N[(Pi / k), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2 \cdot \left(n \cdot \frac{\pi}{k}\right)}
\end{array}
Initial program 99.6%
*-commutative99.6%
*-commutative99.6%
associate-*r*99.6%
div-inv99.7%
expm1-log1p-u96.7%
expm1-udef86.4%
Applied egg-rr73.6%
expm1-def83.9%
expm1-log1p85.4%
associate-*r*85.4%
Simplified85.4%
Taylor expanded in k around 0 36.8%
associate-/l*36.8%
associate-/r/36.8%
Simplified36.8%
expm1-log1p-u35.3%
expm1-udef34.9%
*-commutative34.9%
Applied egg-rr34.9%
expm1-def35.3%
expm1-log1p36.8%
associate-*r/36.8%
*-commutative36.8%
associate-*r/36.8%
Simplified36.8%
Taylor expanded in n around 0 36.8%
associate-*r/36.8%
associate-*l*36.8%
associate-*r/36.8%
associate-*l*36.8%
Simplified36.8%
Final simplification36.8%
herbie shell --seed 2023252
(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))))