
(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 7 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 (* PI (* n 2.0)))) (* (/ 1.0 (sqrt k)) (/ (sqrt t_0) (pow t_0 (* k 0.5))))))
double code(double k, double n) {
double t_0 = ((double) M_PI) * (n * 2.0);
return (1.0 / sqrt(k)) * (sqrt(t_0) / pow(t_0, (k * 0.5)));
}
public static double code(double k, double n) {
double t_0 = Math.PI * (n * 2.0);
return (1.0 / Math.sqrt(k)) * (Math.sqrt(t_0) / Math.pow(t_0, (k * 0.5)));
}
def code(k, n): t_0 = math.pi * (n * 2.0) return (1.0 / math.sqrt(k)) * (math.sqrt(t_0) / math.pow(t_0, (k * 0.5)))
function code(k, n) t_0 = Float64(pi * Float64(n * 2.0)) return Float64(Float64(1.0 / sqrt(k)) * Float64(sqrt(t_0) / (t_0 ^ Float64(k * 0.5)))) end
function tmp = code(k, n) t_0 = pi * (n * 2.0); tmp = (1.0 / sqrt(k)) * (sqrt(t_0) / (t_0 ^ (k * 0.5))); end
code[k_, n_] := Block[{t$95$0 = N[(Pi * N[(n * 2.0), $MachinePrecision]), $MachinePrecision]}, N[(N[(1.0 / N[Sqrt[k], $MachinePrecision]), $MachinePrecision] * N[(N[Sqrt[t$95$0], $MachinePrecision] / N[Power[t$95$0, N[(k * 0.5), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \pi \cdot \left(n \cdot 2\right)\\
\frac{1}{\sqrt{k}} \cdot \frac{\sqrt{t_0}}{{t_0}^{\left(k \cdot 0.5\right)}}
\end{array}
\end{array}
Initial program 99.4%
div-sub99.4%
metadata-eval99.4%
pow-sub99.6%
pow1/299.6%
associate-*l*99.6%
associate-*l*99.6%
div-inv99.6%
metadata-eval99.6%
Applied egg-rr99.6%
*-commutative99.6%
associate-*r*99.6%
*-commutative99.6%
*-commutative99.6%
associate-*r*99.6%
*-commutative99.6%
*-commutative99.6%
Simplified99.6%
Final simplification99.6%
(FPCore (k n)
:precision binary64
(let* ((t_0 (* 2.0 (* n PI))))
(if (<= k 1.4e-41)
(/ 1.0 (/ (sqrt k) (sqrt t_0)))
(sqrt (* (pow t_0 (- 1.0 k)) (/ 1.0 k))))))
double code(double k, double n) {
double t_0 = 2.0 * (n * ((double) M_PI));
double tmp;
if (k <= 1.4e-41) {
tmp = 1.0 / (sqrt(k) / sqrt(t_0));
} else {
tmp = sqrt((pow(t_0, (1.0 - k)) * (1.0 / k)));
}
return tmp;
}
public static double code(double k, double n) {
double t_0 = 2.0 * (n * Math.PI);
double tmp;
if (k <= 1.4e-41) {
tmp = 1.0 / (Math.sqrt(k) / Math.sqrt(t_0));
} else {
tmp = Math.sqrt((Math.pow(t_0, (1.0 - k)) * (1.0 / k)));
}
return tmp;
}
def code(k, n): t_0 = 2.0 * (n * math.pi) tmp = 0 if k <= 1.4e-41: tmp = 1.0 / (math.sqrt(k) / math.sqrt(t_0)) else: tmp = math.sqrt((math.pow(t_0, (1.0 - k)) * (1.0 / k))) return tmp
function code(k, n) t_0 = Float64(2.0 * Float64(n * pi)) tmp = 0.0 if (k <= 1.4e-41) tmp = Float64(1.0 / Float64(sqrt(k) / sqrt(t_0))); else tmp = sqrt(Float64((t_0 ^ Float64(1.0 - k)) * Float64(1.0 / k))); end return tmp end
function tmp_2 = code(k, n) t_0 = 2.0 * (n * pi); tmp = 0.0; if (k <= 1.4e-41) tmp = 1.0 / (sqrt(k) / sqrt(t_0)); else tmp = sqrt(((t_0 ^ (1.0 - k)) * (1.0 / k))); end tmp_2 = tmp; end
code[k_, n_] := Block[{t$95$0 = N[(2.0 * N[(n * Pi), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[k, 1.4e-41], N[(1.0 / N[(N[Sqrt[k], $MachinePrecision] / N[Sqrt[t$95$0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[Power[t$95$0, N[(1.0 - k), $MachinePrecision]], $MachinePrecision] * N[(1.0 / k), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 2 \cdot \left(n \cdot \pi\right)\\
\mathbf{if}\;k \leq 1.4 \cdot 10^{-41}:\\
\;\;\;\;\frac{1}{\frac{\sqrt{k}}{\sqrt{t_0}}}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{{t_0}^{\left(1 - k\right)} \cdot \frac{1}{k}}\\
\end{array}
\end{array}
if k < 1.4000000000000001e-41Initial program 99.3%
*-commutative99.3%
associate-*r*99.3%
associate-/r/99.2%
add-sqr-sqrt98.8%
sqrt-unprod99.2%
associate-*r*99.2%
*-commutative99.2%
associate-*r*99.2%
*-commutative99.2%
pow-prod-up99.2%
Applied egg-rr99.2%
Taylor expanded in k around 0 99.2%
if 1.4000000000000001e-41 < k Initial program 99.5%
*-commutative99.5%
*-commutative99.5%
associate-*r*99.5%
div-inv99.5%
expm1-log1p-u99.1%
expm1-udef95.3%
Applied egg-rr95.3%
expm1-def99.1%
expm1-log1p99.5%
*-commutative99.5%
associate-*r*99.5%
*-commutative99.5%
Simplified99.5%
sub-neg99.5%
unpow-prod-up100.0%
pow1100.0%
associate-*l*100.0%
associate-*l*100.0%
Applied egg-rr100.0%
div-inv100.0%
pow1100.0%
pow-prod-up99.5%
sub-neg99.5%
*-commutative99.5%
associate-*l*99.5%
Applied egg-rr99.5%
Final simplification99.4%
(FPCore (k n) :precision binary64 (* (pow k -0.5) (pow (* n (* 2.0 PI)) (/ (- 1.0 k) 2.0))))
double code(double k, double n) {
return pow(k, -0.5) * pow((n * (2.0 * ((double) M_PI))), ((1.0 - k) / 2.0));
}
public static double code(double k, double n) {
return Math.pow(k, -0.5) * Math.pow((n * (2.0 * Math.PI)), ((1.0 - k) / 2.0));
}
def code(k, n): return math.pow(k, -0.5) * math.pow((n * (2.0 * math.pi)), ((1.0 - k) / 2.0))
function code(k, n) return Float64((k ^ -0.5) * (Float64(n * Float64(2.0 * pi)) ^ Float64(Float64(1.0 - k) / 2.0))) end
function tmp = code(k, n) tmp = (k ^ -0.5) * ((n * (2.0 * pi)) ^ ((1.0 - k) / 2.0)); end
code[k_, n_] := N[(N[Power[k, -0.5], $MachinePrecision] * N[Power[N[(n * N[(2.0 * Pi), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
{k}^{-0.5} \cdot {\left(n \cdot \left(2 \cdot \pi\right)\right)}^{\left(\frac{1 - k}{2}\right)}
\end{array}
Initial program 99.4%
expm1-log1p-u96.2%
expm1-udef72.7%
pow1/272.7%
pow-flip72.7%
metadata-eval72.7%
Applied egg-rr72.7%
expm1-def96.2%
expm1-log1p99.5%
Simplified99.5%
Final simplification99.5%
(FPCore (k n) :precision binary64 (if (<= k 1.55e-43) (/ 1.0 (/ (sqrt k) (sqrt (* 2.0 (* n PI))))) (sqrt (/ (pow (* PI (* n 2.0)) (- 1.0 k)) k))))
double code(double k, double n) {
double tmp;
if (k <= 1.55e-43) {
tmp = 1.0 / (sqrt(k) / sqrt((2.0 * (n * ((double) M_PI)))));
} 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 <= 1.55e-43) {
tmp = 1.0 / (Math.sqrt(k) / Math.sqrt((2.0 * (n * Math.PI))));
} 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 <= 1.55e-43: tmp = 1.0 / (math.sqrt(k) / math.sqrt((2.0 * (n * math.pi)))) 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 <= 1.55e-43) tmp = Float64(1.0 / Float64(sqrt(k) / sqrt(Float64(2.0 * Float64(n * pi))))); 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 <= 1.55e-43) tmp = 1.0 / (sqrt(k) / sqrt((2.0 * (n * pi)))); else tmp = sqrt((((pi * (n * 2.0)) ^ (1.0 - k)) / k)); end tmp_2 = tmp; end
code[k_, n_] := If[LessEqual[k, 1.55e-43], N[(1.0 / N[(N[Sqrt[k], $MachinePrecision] / N[Sqrt[N[(2.0 * N[(n * Pi), $MachinePrecision]), $MachinePrecision]], $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 1.55 \cdot 10^{-43}:\\
\;\;\;\;\frac{1}{\frac{\sqrt{k}}{\sqrt{2 \cdot \left(n \cdot \pi\right)}}}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{{\left(\pi \cdot \left(n \cdot 2\right)\right)}^{\left(1 - k\right)}}{k}}\\
\end{array}
\end{array}
if k < 1.55e-43Initial program 99.3%
*-commutative99.3%
associate-*r*99.3%
associate-/r/99.2%
add-sqr-sqrt98.8%
sqrt-unprod99.2%
associate-*r*99.2%
*-commutative99.2%
associate-*r*99.2%
*-commutative99.2%
pow-prod-up99.2%
Applied egg-rr99.2%
Taylor expanded in k around 0 99.2%
if 1.55e-43 < k Initial program 99.5%
*-commutative99.5%
*-commutative99.5%
associate-*r*99.5%
div-inv99.5%
expm1-log1p-u99.1%
expm1-udef95.3%
Applied egg-rr95.3%
expm1-def99.1%
expm1-log1p99.5%
*-commutative99.5%
associate-*r*99.5%
*-commutative99.5%
Simplified99.5%
Final simplification99.4%
(FPCore (k n) :precision binary64 (/ (pow (* PI (* n 2.0)) (/ (- 1.0 k) 2.0)) (sqrt k)))
double code(double k, double n) {
return pow((((double) M_PI) * (n * 2.0)), ((1.0 - k) / 2.0)) / sqrt(k);
}
public static double code(double k, double n) {
return Math.pow((Math.PI * (n * 2.0)), ((1.0 - k) / 2.0)) / Math.sqrt(k);
}
def code(k, n): return math.pow((math.pi * (n * 2.0)), ((1.0 - k) / 2.0)) / math.sqrt(k)
function code(k, n) return Float64((Float64(pi * Float64(n * 2.0)) ^ Float64(Float64(1.0 - k) / 2.0)) / sqrt(k)) end
function tmp = code(k, n) tmp = ((pi * (n * 2.0)) ^ ((1.0 - k) / 2.0)) / sqrt(k); end
code[k_, n_] := N[(N[Power[N[(Pi * N[(n * 2.0), $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(n \cdot 2\right)\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}
\end{array}
Initial program 99.4%
associate-*l/99.5%
*-lft-identity99.5%
*-commutative99.5%
associate-*l*99.5%
Simplified99.5%
Final simplification99.5%
(FPCore (k n) :precision binary64 (/ 1.0 (/ (sqrt k) (sqrt (* 2.0 (* n PI))))))
double code(double k, double n) {
return 1.0 / (sqrt(k) / sqrt((2.0 * (n * ((double) M_PI)))));
}
public static double code(double k, double n) {
return 1.0 / (Math.sqrt(k) / Math.sqrt((2.0 * (n * Math.PI))));
}
def code(k, n): return 1.0 / (math.sqrt(k) / math.sqrt((2.0 * (n * math.pi))))
function code(k, n) return Float64(1.0 / Float64(sqrt(k) / sqrt(Float64(2.0 * Float64(n * pi))))) end
function tmp = code(k, n) tmp = 1.0 / (sqrt(k) / sqrt((2.0 * (n * pi)))); end
code[k_, n_] := N[(1.0 / N[(N[Sqrt[k], $MachinePrecision] / N[Sqrt[N[(2.0 * N[(n * Pi), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{\frac{\sqrt{k}}{\sqrt{2 \cdot \left(n \cdot \pi\right)}}}
\end{array}
Initial program 99.4%
*-commutative99.4%
associate-*r*99.4%
associate-/r/99.4%
add-sqr-sqrt99.2%
sqrt-unprod99.4%
associate-*r*99.4%
*-commutative99.4%
associate-*r*99.4%
*-commutative99.4%
pow-prod-up99.4%
Applied egg-rr99.4%
Taylor expanded in k around 0 48.9%
Final simplification48.9%
(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%
*-commutative99.4%
associate-*r*99.4%
div-inv99.5%
expm1-log1p-u96.7%
expm1-udef86.5%
Applied egg-rr78.4%
expm1-def88.6%
expm1-log1p90.4%
*-commutative90.4%
associate-*r*90.4%
*-commutative90.4%
Simplified90.4%
sub-neg90.4%
unpow-prod-up90.7%
pow190.7%
associate-*l*90.7%
associate-*l*90.7%
Applied egg-rr90.7%
Taylor expanded in k around 0 39.9%
expm1-log1p-u38.2%
expm1-udef38.6%
*-commutative38.6%
Applied egg-rr38.6%
expm1-def38.2%
expm1-log1p39.9%
*-commutative39.9%
associate-/l*39.9%
associate-/r/39.9%
Simplified39.9%
Final simplification39.9%
herbie shell --seed 2023213
(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))))