
(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 10 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 (* PI n)))) (/ (* (pow t_0 (* k -0.5)) (sqrt t_0)) (sqrt k))))
double code(double k, double n) {
double t_0 = 2.0 * (((double) M_PI) * n);
return (pow(t_0, (k * -0.5)) * sqrt(t_0)) / sqrt(k);
}
public static double code(double k, double n) {
double t_0 = 2.0 * (Math.PI * n);
return (Math.pow(t_0, (k * -0.5)) * Math.sqrt(t_0)) / Math.sqrt(k);
}
def code(k, n): t_0 = 2.0 * (math.pi * n) return (math.pow(t_0, (k * -0.5)) * math.sqrt(t_0)) / math.sqrt(k)
function code(k, n) t_0 = Float64(2.0 * Float64(pi * n)) return Float64(Float64((t_0 ^ Float64(k * -0.5)) * sqrt(t_0)) / sqrt(k)) end
function tmp = code(k, n) t_0 = 2.0 * (pi * n); tmp = ((t_0 ^ (k * -0.5)) * sqrt(t_0)) / sqrt(k); end
code[k_, n_] := Block[{t$95$0 = N[(2.0 * N[(Pi * n), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[Power[t$95$0, N[(k * -0.5), $MachinePrecision]], $MachinePrecision] * N[Sqrt[t$95$0], $MachinePrecision]), $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 2 \cdot \left(\pi \cdot n\right)\\
\frac{{t_0}^{\left(k \cdot -0.5\right)} \cdot \sqrt{t_0}}{\sqrt{k}}
\end{array}
\end{array}
(FPCore (k n) :precision binary64 (let* ((t_0 (* PI (* 2.0 n)))) (if (<= k 1e-26) (/ (sqrt t_0) (sqrt k)) (sqrt (/ (pow t_0 (- 1.0 k)) k)))))
double code(double k, double n) {
double t_0 = ((double) M_PI) * (2.0 * n);
double tmp;
if (k <= 1e-26) {
tmp = sqrt(t_0) / sqrt(k);
} else {
tmp = sqrt((pow(t_0, (1.0 - k)) / k));
}
return tmp;
}
public static double code(double k, double n) {
double t_0 = Math.PI * (2.0 * n);
double tmp;
if (k <= 1e-26) {
tmp = Math.sqrt(t_0) / Math.sqrt(k);
} else {
tmp = Math.sqrt((Math.pow(t_0, (1.0 - k)) / k));
}
return tmp;
}
def code(k, n): t_0 = math.pi * (2.0 * n) tmp = 0 if k <= 1e-26: tmp = math.sqrt(t_0) / math.sqrt(k) else: tmp = math.sqrt((math.pow(t_0, (1.0 - k)) / k)) return tmp
function code(k, n) t_0 = Float64(pi * Float64(2.0 * n)) tmp = 0.0 if (k <= 1e-26) tmp = Float64(sqrt(t_0) / sqrt(k)); else tmp = sqrt(Float64((t_0 ^ Float64(1.0 - k)) / k)); end return tmp end
function tmp_2 = code(k, n) t_0 = pi * (2.0 * n); tmp = 0.0; if (k <= 1e-26) tmp = sqrt(t_0) / sqrt(k); else tmp = sqrt(((t_0 ^ (1.0 - k)) / k)); end tmp_2 = tmp; end
code[k_, n_] := Block[{t$95$0 = N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[k, 1e-26], N[(N[Sqrt[t$95$0], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision], N[Sqrt[N[(N[Power[t$95$0, N[(1.0 - k), $MachinePrecision]], $MachinePrecision] / k), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \pi \cdot \left(2 \cdot n\right)\\
\mathbf{if}\;k \leq 10^{-26}:\\
\;\;\;\;\frac{\sqrt{t_0}}{\sqrt{k}}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{\frac{{t_0}^{\left(1 - k\right)}}{k}}\\
\end{array}
\end{array}
(FPCore (k n) :precision binary64 (/ (pow (* PI (* 2.0 n)) (+ 0.5 (* k -0.5))) (sqrt k)))
double code(double k, double n) {
return pow((((double) M_PI) * (2.0 * n)), (0.5 + (k * -0.5))) / sqrt(k);
}
public static double code(double k, double n) {
return Math.pow((Math.PI * (2.0 * n)), (0.5 + (k * -0.5))) / Math.sqrt(k);
}
def code(k, n): return math.pow((math.pi * (2.0 * n)), (0.5 + (k * -0.5))) / math.sqrt(k)
function code(k, n) return Float64((Float64(pi * Float64(2.0 * n)) ^ Float64(0.5 + Float64(k * -0.5))) / sqrt(k)) end
function tmp = code(k, n) tmp = ((pi * (2.0 * n)) ^ (0.5 + (k * -0.5))) / sqrt(k); end
code[k_, n_] := N[(N[Power[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision], N[(0.5 + N[(k * -0.5), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(0.5 + k \cdot -0.5\right)}}{\sqrt{k}}
\end{array}
(FPCore (k n) :precision binary64 (if (<= k 7e+232) (/ (sqrt (* PI (* 2.0 n))) (sqrt k)) (cbrt (pow (* 2.0 (/ n (/ k PI))) 1.5))))
double code(double k, double n) {
double tmp;
if (k <= 7e+232) {
tmp = sqrt((((double) M_PI) * (2.0 * n))) / sqrt(k);
} else {
tmp = cbrt(pow((2.0 * (n / (k / ((double) M_PI)))), 1.5));
}
return tmp;
}
public static double code(double k, double n) {
double tmp;
if (k <= 7e+232) {
tmp = Math.sqrt((Math.PI * (2.0 * n))) / Math.sqrt(k);
} else {
tmp = Math.cbrt(Math.pow((2.0 * (n / (k / Math.PI))), 1.5));
}
return tmp;
}
function code(k, n) tmp = 0.0 if (k <= 7e+232) tmp = Float64(sqrt(Float64(pi * Float64(2.0 * n))) / sqrt(k)); else tmp = cbrt((Float64(2.0 * Float64(n / Float64(k / pi))) ^ 1.5)); end return tmp end
code[k_, n_] := If[LessEqual[k, 7e+232], N[(N[Sqrt[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision], N[Power[N[Power[N[(2.0 * N[(n / N[(k / Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.5], $MachinePrecision], 1/3], $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;k \leq 7 \cdot 10^{+232}:\\
\;\;\;\;\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\sqrt{k}}\\
\mathbf{else}:\\
\;\;\;\;\sqrt[3]{{\left(2 \cdot \frac{n}{\frac{k}{\pi}}\right)}^{1.5}}\\
\end{array}
\end{array}
(FPCore (k n) :precision binary64 (/ (sqrt n) (sqrt (/ (/ k 2.0) PI))))
double code(double k, double n) {
return sqrt(n) / sqrt(((k / 2.0) / ((double) M_PI)));
}
public static double code(double k, double n) {
return Math.sqrt(n) / Math.sqrt(((k / 2.0) / Math.PI));
}
def code(k, n): return math.sqrt(n) / math.sqrt(((k / 2.0) / math.pi))
function code(k, n) return Float64(sqrt(n) / sqrt(Float64(Float64(k / 2.0) / pi))) end
function tmp = code(k, n) tmp = sqrt(n) / sqrt(((k / 2.0) / pi)); end
code[k_, n_] := N[(N[Sqrt[n], $MachinePrecision] / N[Sqrt[N[(N[(k / 2.0), $MachinePrecision] / Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sqrt{n}}{\sqrt{\frac{\frac{k}{2}}{\pi}}}
\end{array}
(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}
(FPCore (k n) :precision binary64 (pow (* (/ k PI) (/ 0.5 n)) -0.5))
double code(double k, double n) {
return pow(((k / ((double) M_PI)) * (0.5 / n)), -0.5);
}
public static double code(double k, double n) {
return Math.pow(((k / Math.PI) * (0.5 / n)), -0.5);
}
def code(k, n): return math.pow(((k / math.pi) * (0.5 / n)), -0.5)
function code(k, n) return Float64(Float64(k / pi) * Float64(0.5 / n)) ^ -0.5 end
function tmp = code(k, n) tmp = ((k / pi) * (0.5 / n)) ^ -0.5; end
code[k_, n_] := N[Power[N[(N[(k / Pi), $MachinePrecision] * N[(0.5 / n), $MachinePrecision]), $MachinePrecision], -0.5], $MachinePrecision]
\begin{array}{l}
\\
{\left(\frac{k}{\pi} \cdot \frac{0.5}{n}\right)}^{-0.5}
\end{array}
(FPCore (k n) :precision binary64 (pow (/ k (* n (* 2.0 PI))) -0.5))
double code(double k, double n) {
return pow((k / (n * (2.0 * ((double) M_PI)))), -0.5);
}
public static double code(double k, double n) {
return Math.pow((k / (n * (2.0 * Math.PI))), -0.5);
}
def code(k, n): return math.pow((k / (n * (2.0 * math.pi))), -0.5)
function code(k, n) return Float64(k / Float64(n * Float64(2.0 * pi))) ^ -0.5 end
function tmp = code(k, n) tmp = (k / (n * (2.0 * pi))) ^ -0.5; end
code[k_, n_] := N[Power[N[(k / N[(n * N[(2.0 * Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], -0.5], $MachinePrecision]
\begin{array}{l}
\\
{\left(\frac{k}{n \cdot \left(2 \cdot \pi\right)}\right)}^{-0.5}
\end{array}
(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}
(FPCore (k n) :precision binary64 (sqrt (* 2.0 (/ n (/ k PI)))))
double code(double k, double n) {
return sqrt((2.0 * (n / (k / ((double) M_PI)))));
}
public static double code(double k, double n) {
return Math.sqrt((2.0 * (n / (k / Math.PI))));
}
def code(k, n): return math.sqrt((2.0 * (n / (k / math.pi))))
function code(k, n) return sqrt(Float64(2.0 * Float64(n / Float64(k / pi)))) end
function tmp = code(k, n) tmp = sqrt((2.0 * (n / (k / pi)))); end
code[k_, n_] := N[Sqrt[N[(2.0 * N[(n / N[(k / Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\sqrt{2 \cdot \frac{n}{\frac{k}{\pi}}}
\end{array}
herbie shell --seed 2023340
(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))))