
(FPCore (u1 u2) :precision binary64 (+ (* (* (/ 1.0 6.0) (pow (* -2.0 (log u1)) 0.5)) (cos (* (* 2.0 PI) u2))) 0.5))
double code(double u1, double u2) {
return (((1.0 / 6.0) * pow((-2.0 * log(u1)), 0.5)) * cos(((2.0 * ((double) M_PI)) * u2))) + 0.5;
}
public static double code(double u1, double u2) {
return (((1.0 / 6.0) * Math.pow((-2.0 * Math.log(u1)), 0.5)) * Math.cos(((2.0 * Math.PI) * u2))) + 0.5;
}
def code(u1, u2): return (((1.0 / 6.0) * math.pow((-2.0 * math.log(u1)), 0.5)) * math.cos(((2.0 * math.pi) * u2))) + 0.5
function code(u1, u2) return Float64(Float64(Float64(Float64(1.0 / 6.0) * (Float64(-2.0 * log(u1)) ^ 0.5)) * cos(Float64(Float64(2.0 * pi) * u2))) + 0.5) end
function tmp = code(u1, u2) tmp = (((1.0 / 6.0) * ((-2.0 * log(u1)) ^ 0.5)) * cos(((2.0 * pi) * u2))) + 0.5; end
code[u1_, u2_] := N[(N[(N[(N[(1.0 / 6.0), $MachinePrecision] * N[Power[N[(-2.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision], 0.5], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(N[(2.0 * Pi), $MachinePrecision] * u2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{6} \cdot {\left(-2 \cdot \log u1\right)}^{0.5}\right) \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right) + 0.5
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (u1 u2) :precision binary64 (+ (* (* (/ 1.0 6.0) (pow (* -2.0 (log u1)) 0.5)) (cos (* (* 2.0 PI) u2))) 0.5))
double code(double u1, double u2) {
return (((1.0 / 6.0) * pow((-2.0 * log(u1)), 0.5)) * cos(((2.0 * ((double) M_PI)) * u2))) + 0.5;
}
public static double code(double u1, double u2) {
return (((1.0 / 6.0) * Math.pow((-2.0 * Math.log(u1)), 0.5)) * Math.cos(((2.0 * Math.PI) * u2))) + 0.5;
}
def code(u1, u2): return (((1.0 / 6.0) * math.pow((-2.0 * math.log(u1)), 0.5)) * math.cos(((2.0 * math.pi) * u2))) + 0.5
function code(u1, u2) return Float64(Float64(Float64(Float64(1.0 / 6.0) * (Float64(-2.0 * log(u1)) ^ 0.5)) * cos(Float64(Float64(2.0 * pi) * u2))) + 0.5) end
function tmp = code(u1, u2) tmp = (((1.0 / 6.0) * ((-2.0 * log(u1)) ^ 0.5)) * cos(((2.0 * pi) * u2))) + 0.5; end
code[u1_, u2_] := N[(N[(N[(N[(1.0 / 6.0), $MachinePrecision] * N[Power[N[(-2.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision], 0.5], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(N[(2.0 * Pi), $MachinePrecision] * u2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{6} \cdot {\left(-2 \cdot \log u1\right)}^{0.5}\right) \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right) + 0.5
\end{array}
(FPCore (u1 u2) :precision binary64 (fma (pow (* -1.0 (log u1)) 0.5) (* (* 0.16666666666666666 (pow 2.0 0.5)) (sin (fma (* PI u2) -2.0 (/ PI 2.0)))) 0.5))
double code(double u1, double u2) {
return fma(pow((-1.0 * log(u1)), 0.5), ((0.16666666666666666 * pow(2.0, 0.5)) * sin(fma((((double) M_PI) * u2), -2.0, (((double) M_PI) / 2.0)))), 0.5);
}
function code(u1, u2) return fma((Float64(-1.0 * log(u1)) ^ 0.5), Float64(Float64(0.16666666666666666 * (2.0 ^ 0.5)) * sin(fma(Float64(pi * u2), -2.0, Float64(pi / 2.0)))), 0.5) end
code[u1_, u2_] := N[(N[Power[N[(-1.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision], 0.5], $MachinePrecision] * N[(N[(0.16666666666666666 * N[Power[2.0, 0.5], $MachinePrecision]), $MachinePrecision] * N[Sin[N[(N[(Pi * u2), $MachinePrecision] * -2.0 + N[(Pi / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left({\left(-1 \cdot \log u1\right)}^{0.5}, \left(0.16666666666666666 \cdot {2}^{0.5}\right) \cdot \sin \left(\mathsf{fma}\left(\pi \cdot u2, -2, \frac{\pi}{2}\right)\right), 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
(FPCore (u1 u2) :precision binary64 (fma (* (pow (* -1.0 (log u1)) 0.5) 0.16666666666666666) (* (pow 2.0 0.5) (sin (fma (* PI u2) -2.0 (/ PI 2.0)))) 0.5))
double code(double u1, double u2) {
return fma((pow((-1.0 * log(u1)), 0.5) * 0.16666666666666666), (pow(2.0, 0.5) * sin(fma((((double) M_PI) * u2), -2.0, (((double) M_PI) / 2.0)))), 0.5);
}
function code(u1, u2) return fma(Float64((Float64(-1.0 * log(u1)) ^ 0.5) * 0.16666666666666666), Float64((2.0 ^ 0.5) * sin(fma(Float64(pi * u2), -2.0, Float64(pi / 2.0)))), 0.5) end
code[u1_, u2_] := N[(N[(N[Power[N[(-1.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision], 0.5], $MachinePrecision] * 0.16666666666666666), $MachinePrecision] * N[(N[Power[2.0, 0.5], $MachinePrecision] * N[Sin[N[(N[(Pi * u2), $MachinePrecision] * -2.0 + N[(Pi / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left({\left(-1 \cdot \log u1\right)}^{0.5} \cdot 0.16666666666666666, {2}^{0.5} \cdot \sin \left(\mathsf{fma}\left(\pi \cdot u2, -2, \frac{\pi}{2}\right)\right), 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
(FPCore (u1 u2) :precision binary64 (fma 0.16666666666666666 (* (pow (* (log u1) -2.0) 0.5) (sin (fma (* PI 2.0) u2 (/ PI 2.0)))) 0.5))
double code(double u1, double u2) {
return fma(0.16666666666666666, (pow((log(u1) * -2.0), 0.5) * sin(fma((((double) M_PI) * 2.0), u2, (((double) M_PI) / 2.0)))), 0.5);
}
function code(u1, u2) return fma(0.16666666666666666, Float64((Float64(log(u1) * -2.0) ^ 0.5) * sin(fma(Float64(pi * 2.0), u2, Float64(pi / 2.0)))), 0.5) end
code[u1_, u2_] := N[(0.16666666666666666 * N[(N[Power[N[(N[Log[u1], $MachinePrecision] * -2.0), $MachinePrecision], 0.5], $MachinePrecision] * N[Sin[N[(N[(Pi * 2.0), $MachinePrecision] * u2 + N[(Pi / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(0.16666666666666666, {\left(\log u1 \cdot -2\right)}^{0.5} \cdot \sin \left(\mathsf{fma}\left(\pi \cdot 2, u2, \frac{\pi}{2}\right)\right), 0.5\right)
\end{array}
Initial program 99.4%
lift-pow.f64N/A
lift-*.f64N/A
lift-log.f64N/A
pow-to-expN/A
exp-prodN/A
lower-pow.f64N/A
lower-exp.f64N/A
lower-log.f64N/A
*-commutativeN/A
lower-*.f64N/A
lift-log.f6498.9
Applied rewrites98.9%
Applied rewrites99.4%
(FPCore (u1 u2) :precision binary64 (+ (* (* (/ 1.0 6.0) (pow (* -2.0 (log u1)) 0.5)) (cos (* (* 2.0 PI) u2))) 0.5))
double code(double u1, double u2) {
return (((1.0 / 6.0) * pow((-2.0 * log(u1)), 0.5)) * cos(((2.0 * ((double) M_PI)) * u2))) + 0.5;
}
public static double code(double u1, double u2) {
return (((1.0 / 6.0) * Math.pow((-2.0 * Math.log(u1)), 0.5)) * Math.cos(((2.0 * Math.PI) * u2))) + 0.5;
}
def code(u1, u2): return (((1.0 / 6.0) * math.pow((-2.0 * math.log(u1)), 0.5)) * math.cos(((2.0 * math.pi) * u2))) + 0.5
function code(u1, u2) return Float64(Float64(Float64(Float64(1.0 / 6.0) * (Float64(-2.0 * log(u1)) ^ 0.5)) * cos(Float64(Float64(2.0 * pi) * u2))) + 0.5) end
function tmp = code(u1, u2) tmp = (((1.0 / 6.0) * ((-2.0 * log(u1)) ^ 0.5)) * cos(((2.0 * pi) * u2))) + 0.5; end
code[u1_, u2_] := N[(N[(N[(N[(1.0 / 6.0), $MachinePrecision] * N[Power[N[(-2.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision], 0.5], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(N[(2.0 * Pi), $MachinePrecision] * u2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{6} \cdot {\left(-2 \cdot \log u1\right)}^{0.5}\right) \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right) + 0.5
\end{array}
Initial program 99.4%
(FPCore (u1 u2)
:precision binary64
(let* ((t_0 (pow (* (log u1) -2.0) 0.5)) (t_1 (pow t_0 0.25)))
(+
(*
(* (* t_1 t_1) (* (pow t_0 0.5) 0.16666666666666666))
(cos (* (* 2.0 PI) u2)))
0.5)))
double code(double u1, double u2) {
double t_0 = pow((log(u1) * -2.0), 0.5);
double t_1 = pow(t_0, 0.25);
return (((t_1 * t_1) * (pow(t_0, 0.5) * 0.16666666666666666)) * cos(((2.0 * ((double) M_PI)) * u2))) + 0.5;
}
public static double code(double u1, double u2) {
double t_0 = Math.pow((Math.log(u1) * -2.0), 0.5);
double t_1 = Math.pow(t_0, 0.25);
return (((t_1 * t_1) * (Math.pow(t_0, 0.5) * 0.16666666666666666)) * Math.cos(((2.0 * Math.PI) * u2))) + 0.5;
}
def code(u1, u2): t_0 = math.pow((math.log(u1) * -2.0), 0.5) t_1 = math.pow(t_0, 0.25) return (((t_1 * t_1) * (math.pow(t_0, 0.5) * 0.16666666666666666)) * math.cos(((2.0 * math.pi) * u2))) + 0.5
function code(u1, u2) t_0 = Float64(log(u1) * -2.0) ^ 0.5 t_1 = t_0 ^ 0.25 return Float64(Float64(Float64(Float64(t_1 * t_1) * Float64((t_0 ^ 0.5) * 0.16666666666666666)) * cos(Float64(Float64(2.0 * pi) * u2))) + 0.5) end
function tmp = code(u1, u2) t_0 = (log(u1) * -2.0) ^ 0.5; t_1 = t_0 ^ 0.25; tmp = (((t_1 * t_1) * ((t_0 ^ 0.5) * 0.16666666666666666)) * cos(((2.0 * pi) * u2))) + 0.5; end
code[u1_, u2_] := Block[{t$95$0 = N[Power[N[(N[Log[u1], $MachinePrecision] * -2.0), $MachinePrecision], 0.5], $MachinePrecision]}, Block[{t$95$1 = N[Power[t$95$0, 0.25], $MachinePrecision]}, N[(N[(N[(N[(t$95$1 * t$95$1), $MachinePrecision] * N[(N[Power[t$95$0, 0.5], $MachinePrecision] * 0.16666666666666666), $MachinePrecision]), $MachinePrecision] * N[Cos[N[(N[(2.0 * Pi), $MachinePrecision] * u2), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := {\left(\log u1 \cdot -2\right)}^{0.5}\\
t_1 := {t\_0}^{0.25}\\
\left(\left(t\_1 \cdot t\_1\right) \cdot \left({t\_0}^{0.5} \cdot 0.16666666666666666\right)\right) \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right) + 0.5
\end{array}
\end{array}
Initial program 99.4%
lift-*.f64N/A
lift-/.f64N/A
lift-pow.f64N/A
lift-*.f64N/A
lift-log.f64N/A
*-commutativeN/A
sqr-powN/A
associate-*l*N/A
lower-*.f64N/A
metadata-evalN/A
metadata-evalN/A
pow-unpowN/A
lower-pow.f64N/A
lower-pow.f64N/A
*-commutativeN/A
lower-*.f64N/A
lift-log.f64N/A
lower-*.f64N/A
Applied rewrites99.0%
lift-pow.f64N/A
lift-pow.f64N/A
lift-*.f64N/A
lift-log.f64N/A
sqr-powN/A
lower-*.f64N/A
metadata-evalN/A
lower-pow.f64N/A
lift-log.f64N/A
lift-*.f64N/A
lift-pow.f64N/A
metadata-evalN/A
lower-pow.f64N/A
lift-log.f64N/A
lift-*.f64N/A
lift-pow.f6498.9
Applied rewrites98.9%
herbie shell --seed 2025064
(FPCore (u1 u2)
:name "normal distribution"
:precision binary64
:pre (and (and (<= 0.0 u1) (<= u1 1.0)) (and (<= 0.0 u2) (<= u2 1.0)))
(+ (* (* (/ 1.0 6.0) (pow (* -2.0 (log u1)) 0.5)) (cos (* (* 2.0 PI) u2))) 0.5))