
(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 (/ (pow (* PI (* n 2.0)) (fma k -0.5 0.5)) (sqrt k)))
double code(double k, double n) {
return pow((((double) M_PI) * (n * 2.0)), fma(k, -0.5, 0.5)) / sqrt(k);
}
function code(k, n) return Float64((Float64(pi * Float64(n * 2.0)) ^ fma(k, -0.5, 0.5)) / sqrt(k)) end
code[k_, n_] := N[(N[Power[N[(Pi * N[(n * 2.0), $MachinePrecision]), $MachinePrecision], N[(k * -0.5 + 0.5), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{{\left(\pi \cdot \left(n \cdot 2\right)\right)}^{\left(\mathsf{fma}\left(k, -0.5, 0.5\right)\right)}}{\sqrt{k}}
\end{array}
Initial program 99.4%
lift-/.f64N/A
lift--.f64N/A
div-subN/A
metadata-evalN/A
sub-negN/A
+-commutativeN/A
div-invN/A
metadata-evalN/A
distribute-rgt-neg-inN/A
metadata-evalN/A
metadata-evalN/A
lower-fma.f64N/A
metadata-eval99.4
Applied rewrites99.4%
lift-*.f64N/A
*-commutativeN/A
lift-/.f64N/A
un-div-invN/A
lower-/.f6499.5
lift-*.f64N/A
*-commutativeN/A
lift-*.f64N/A
associate-*r*N/A
lift-*.f64N/A
lower-*.f6499.5
lift-*.f64N/A
*-commutativeN/A
lower-*.f6499.5
Applied rewrites99.5%
Final simplification99.5%
(FPCore (k n) :precision binary64 (* (sqrt n) (sqrt (* (/ PI k) 2.0))))
double code(double k, double n) {
return sqrt(n) * sqrt(((((double) M_PI) / k) * 2.0));
}
public static double code(double k, double n) {
return Math.sqrt(n) * Math.sqrt(((Math.PI / k) * 2.0));
}
def code(k, n): return math.sqrt(n) * math.sqrt(((math.pi / k) * 2.0))
function code(k, n) return Float64(sqrt(n) * sqrt(Float64(Float64(pi / k) * 2.0))) end
function tmp = code(k, n) tmp = sqrt(n) * sqrt(((pi / k) * 2.0)); end
code[k_, n_] := N[(N[Sqrt[n], $MachinePrecision] * N[Sqrt[N[(N[(Pi / k), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{n} \cdot \sqrt{\frac{\pi}{k} \cdot 2}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-PI.f6438.5
Applied rewrites38.5%
Applied rewrites38.5%
Applied rewrites48.8%
Final simplification48.8%
(FPCore (k n) :precision binary64 (* (sqrt (* (/ 2.0 k) PI)) (sqrt n)))
double code(double k, double n) {
return sqrt(((2.0 / k) * ((double) M_PI))) * sqrt(n);
}
public static double code(double k, double n) {
return Math.sqrt(((2.0 / k) * Math.PI)) * Math.sqrt(n);
}
def code(k, n): return math.sqrt(((2.0 / k) * math.pi)) * math.sqrt(n)
function code(k, n) return Float64(sqrt(Float64(Float64(2.0 / k) * pi)) * sqrt(n)) end
function tmp = code(k, n) tmp = sqrt(((2.0 / k) * pi)) * sqrt(n); end
code[k_, n_] := N[(N[Sqrt[N[(N[(2.0 / k), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision] * N[Sqrt[n], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\frac{2}{k} \cdot \pi} \cdot \sqrt{n}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-PI.f6438.5
Applied rewrites38.5%
Applied rewrites38.5%
Applied rewrites48.7%
(FPCore (k n) :precision binary64 (sqrt (* (/ n (/ k PI)) 2.0)))
double code(double k, double n) {
return sqrt(((n / (k / ((double) M_PI))) * 2.0));
}
public static double code(double k, double n) {
return Math.sqrt(((n / (k / Math.PI)) * 2.0));
}
def code(k, n): return math.sqrt(((n / (k / math.pi)) * 2.0))
function code(k, n) return sqrt(Float64(Float64(n / Float64(k / pi)) * 2.0)) end
function tmp = code(k, n) tmp = sqrt(((n / (k / pi)) * 2.0)); end
code[k_, n_] := N[Sqrt[N[(N[(n / N[(k / Pi), $MachinePrecision]), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\frac{n}{\frac{k}{\pi}} \cdot 2}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-PI.f6438.5
Applied rewrites38.5%
Applied rewrites38.5%
Applied rewrites38.5%
(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(Float64(Float64(pi * n) / k) * 2.0)) end
function tmp = code(k, n) tmp = sqrt((((pi * n) / k) * 2.0)); end
code[k_, n_] := N[Sqrt[N[(N[(N[(Pi * n), $MachinePrecision] / k), $MachinePrecision] * 2.0), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\frac{\pi \cdot n}{k} \cdot 2}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-PI.f6438.5
Applied rewrites38.5%
Applied rewrites38.5%
(FPCore (k n) :precision binary64 (sqrt (* (/ n k) (* PI 2.0))))
double code(double k, double n) {
return sqrt(((n / k) * (((double) M_PI) * 2.0)));
}
public static double code(double k, double n) {
return Math.sqrt(((n / k) * (Math.PI * 2.0)));
}
def code(k, n): return math.sqrt(((n / k) * (math.pi * 2.0)))
function code(k, n) return sqrt(Float64(Float64(n / k) * Float64(pi * 2.0))) end
function tmp = code(k, n) tmp = sqrt(((n / k) * (pi * 2.0))); end
code[k_, n_] := N[Sqrt[N[(N[(n / k), $MachinePrecision] * N[(Pi * 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{\frac{n}{k} \cdot \left(\pi \cdot 2\right)}
\end{array}
Initial program 99.4%
Taylor expanded in k around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-PI.f6438.5
Applied rewrites38.5%
Applied rewrites38.5%
Applied rewrites38.5%
Final simplification38.5%
herbie shell --seed 2024235
(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))))