
(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 9 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 (* (* (sin (fma (* -2.0 u2) PI (/ PI 2.0))) (sqrt 2.0)) 0.16666666666666666) (sqrt (- (log u1))) 0.5))
double code(double u1, double u2) {
return fma(((sin(fma((-2.0 * u2), ((double) M_PI), (((double) M_PI) / 2.0))) * sqrt(2.0)) * 0.16666666666666666), sqrt(-log(u1)), 0.5);
}
function code(u1, u2) return fma(Float64(Float64(sin(fma(Float64(-2.0 * u2), pi, Float64(pi / 2.0))) * sqrt(2.0)) * 0.16666666666666666), sqrt(Float64(-log(u1))), 0.5) end
code[u1_, u2_] := N[(N[(N[(N[Sin[N[(N[(-2.0 * u2), $MachinePrecision] * Pi + N[(Pi / 2.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * 0.16666666666666666), $MachinePrecision] * N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\left(\sin \left(\mathsf{fma}\left(-2 \cdot u2, \pi, \frac{\pi}{2}\right)\right) \cdot \sqrt{2}\right) \cdot 0.16666666666666666, \sqrt{-\log u1}, 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
lift-*.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
lift-cos.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
*-commutativeN/A
*-commutativeN/A
associate-*r*N/A
lower-*.f64N/A
Applied rewrites99.5%
Applied rewrites99.5%
lift-cos.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
sin-+PI/2-revN/A
lower-sin.f64N/A
lower-fma.f64N/A
*-commutativeN/A
lower-*.f64N/A
lift-PI.f64N/A
lower-/.f64N/A
lift-PI.f6499.5
Applied rewrites99.5%
(FPCore (u1 u2) :precision binary64 (fma (* (* 0.16666666666666666 (sqrt 2.0)) (cos (* (* PI u2) -2.0))) (sqrt (- (log u1))) 0.5))
double code(double u1, double u2) {
return fma(((0.16666666666666666 * sqrt(2.0)) * cos(((((double) M_PI) * u2) * -2.0))), sqrt(-log(u1)), 0.5);
}
function code(u1, u2) return fma(Float64(Float64(0.16666666666666666 * sqrt(2.0)) * cos(Float64(Float64(pi * u2) * -2.0))), sqrt(Float64(-log(u1))), 0.5) end
code[u1_, u2_] := N[(N[(N[(0.16666666666666666 * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(N[(Pi * u2), $MachinePrecision] * -2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\left(0.16666666666666666 \cdot \sqrt{2}\right) \cdot \cos \left(\left(\pi \cdot u2\right) \cdot -2\right), \sqrt{-\log u1}, 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
(FPCore (u1 u2) :precision binary64 (fma (* (* 0.16666666666666666 (cos (* (* -2.0 u2) PI))) (sqrt 2.0)) (sqrt (- (log u1))) 0.5))
double code(double u1, double u2) {
return fma(((0.16666666666666666 * cos(((-2.0 * u2) * ((double) M_PI)))) * sqrt(2.0)), sqrt(-log(u1)), 0.5);
}
function code(u1, u2) return fma(Float64(Float64(0.16666666666666666 * cos(Float64(Float64(-2.0 * u2) * pi))) * sqrt(2.0)), sqrt(Float64(-log(u1))), 0.5) end
code[u1_, u2_] := N[(N[(N[(0.16666666666666666 * N[Cos[N[(N[(-2.0 * u2), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\left(0.16666666666666666 \cdot \cos \left(\left(-2 \cdot u2\right) \cdot \pi\right)\right) \cdot \sqrt{2}, \sqrt{-\log u1}, 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
lift-*.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
lift-cos.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
*-commutativeN/A
*-commutativeN/A
associate-*r*N/A
lower-*.f64N/A
Applied rewrites99.5%
(FPCore (u1 u2) :precision binary64 (fma (* (sqrt 2.0) 0.16666666666666666) (* (cos (* (* -2.0 u2) PI)) (sqrt (- (log u1)))) 0.5))
double code(double u1, double u2) {
return fma((sqrt(2.0) * 0.16666666666666666), (cos(((-2.0 * u2) * ((double) M_PI))) * sqrt(-log(u1))), 0.5);
}
function code(u1, u2) return fma(Float64(sqrt(2.0) * 0.16666666666666666), Float64(cos(Float64(Float64(-2.0 * u2) * pi)) * sqrt(Float64(-log(u1)))), 0.5) end
code[u1_, u2_] := N[(N[(N[Sqrt[2.0], $MachinePrecision] * 0.16666666666666666), $MachinePrecision] * N[(N[Cos[N[(N[(-2.0 * u2), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision] * N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{2} \cdot 0.16666666666666666, \cos \left(\left(-2 \cdot u2\right) \cdot \pi\right) \cdot \sqrt{-\log u1}, 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
lift-fma.f64N/A
lift-*.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
lift-cos.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
lift-neg.f64N/A
lift-log.f64N/A
associate-*l*N/A
Applied rewrites99.5%
(FPCore (u1 u2) :precision binary64 (fma (sqrt 2.0) (* 0.16666666666666666 (* (sqrt (- (log u1))) (cos (* (* u2 -2.0) PI)))) 0.5))
double code(double u1, double u2) {
return fma(sqrt(2.0), (0.16666666666666666 * (sqrt(-log(u1)) * cos(((u2 * -2.0) * ((double) M_PI))))), 0.5);
}
function code(u1, u2) return fma(sqrt(2.0), Float64(0.16666666666666666 * Float64(sqrt(Float64(-log(u1))) * cos(Float64(Float64(u2 * -2.0) * pi)))), 0.5) end
code[u1_, u2_] := N[(N[Sqrt[2.0], $MachinePrecision] * N[(0.16666666666666666 * N[(N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] * N[Cos[N[(N[(u2 * -2.0), $MachinePrecision] * Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{2}, 0.16666666666666666 \cdot \left(\sqrt{-\log u1} \cdot \cos \left(\left(u2 \cdot -2\right) \cdot \pi\right)\right), 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
lift-*.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
lift-cos.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
*-commutativeN/A
*-commutativeN/A
associate-*r*N/A
lower-*.f64N/A
Applied rewrites99.5%
Applied rewrites99.5%
(FPCore (u1 u2) :precision binary64 (fma (* (cos (* (* PI u2) -2.0)) (sqrt (* (log u1) -2.0))) 0.16666666666666666 0.5))
double code(double u1, double u2) {
return fma((cos(((((double) M_PI) * u2) * -2.0)) * sqrt((log(u1) * -2.0))), 0.16666666666666666, 0.5);
}
function code(u1, u2) return fma(Float64(cos(Float64(Float64(pi * u2) * -2.0)) * sqrt(Float64(log(u1) * -2.0))), 0.16666666666666666, 0.5) end
code[u1_, u2_] := N[(N[(N[Cos[N[(N[(Pi * u2), $MachinePrecision] * -2.0), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(N[Log[u1], $MachinePrecision] * -2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * 0.16666666666666666 + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(\left(\pi \cdot u2\right) \cdot -2\right) \cdot \sqrt{\log u1 \cdot -2}, 0.16666666666666666, 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.4%
(FPCore (u1 u2) :precision binary64 (fma (* (fma (* (* PI u2) (* PI u2)) -0.3333333333333333 0.16666666666666666) (sqrt 2.0)) (sqrt (- (log u1))) 0.5))
double code(double u1, double u2) {
return fma((fma(((((double) M_PI) * u2) * (((double) M_PI) * u2)), -0.3333333333333333, 0.16666666666666666) * sqrt(2.0)), sqrt(-log(u1)), 0.5);
}
function code(u1, u2) return fma(Float64(fma(Float64(Float64(pi * u2) * Float64(pi * u2)), -0.3333333333333333, 0.16666666666666666) * sqrt(2.0)), sqrt(Float64(-log(u1))), 0.5) end
code[u1_, u2_] := N[(N[(N[(N[(N[(Pi * u2), $MachinePrecision] * N[(Pi * u2), $MachinePrecision]), $MachinePrecision] * -0.3333333333333333 + 0.16666666666666666), $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\mathsf{fma}\left(\left(\pi \cdot u2\right) \cdot \left(\pi \cdot u2\right), -0.3333333333333333, 0.16666666666666666\right) \cdot \sqrt{2}, \sqrt{-\log u1}, 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
lift-*.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
lift-cos.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
*-commutativeN/A
*-commutativeN/A
associate-*r*N/A
lower-*.f64N/A
Applied rewrites99.5%
Taylor expanded in u2 around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
pow-prod-downN/A
lower-pow.f64N/A
*-commutativeN/A
lower-*.f64N/A
lift-PI.f6498.3
Applied rewrites98.3%
lift-pow.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
unpow2N/A
lower-*.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift-PI.f6498.3
Applied rewrites98.3%
(FPCore (u1 u2) :precision binary64 (fma (* (sqrt 2.0) 0.16666666666666666) (sqrt (- (log u1))) 0.5))
double code(double u1, double u2) {
return fma((sqrt(2.0) * 0.16666666666666666), sqrt(-log(u1)), 0.5);
}
function code(u1, u2) return fma(Float64(sqrt(2.0) * 0.16666666666666666), sqrt(Float64(-log(u1))), 0.5) end
code[u1_, u2_] := N[(N[(N[Sqrt[2.0], $MachinePrecision] * 0.16666666666666666), $MachinePrecision] * N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{2} \cdot 0.16666666666666666, \sqrt{-\log u1}, 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
Taylor expanded in u2 around 0
*-commutativeN/A
lower-*.f64N/A
lift-sqrt.f6497.6
Applied rewrites97.6%
(FPCore (u1 u2) :precision binary64 (fma (sqrt (* (log u1) -2.0)) 0.16666666666666666 0.5))
double code(double u1, double u2) {
return fma(sqrt((log(u1) * -2.0)), 0.16666666666666666, 0.5);
}
function code(u1, u2) return fma(sqrt(Float64(log(u1) * -2.0)), 0.16666666666666666, 0.5) end
code[u1_, u2_] := N[(N[Sqrt[N[(N[Log[u1], $MachinePrecision] * -2.0), $MachinePrecision]], $MachinePrecision] * 0.16666666666666666 + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{\log u1 \cdot -2}, 0.16666666666666666, 0.5\right)
\end{array}
Initial program 99.4%
Taylor expanded in u2 around 0
metadata-evalN/A
+-commutativeN/A
*-commutativeN/A
sqrt-unprodN/A
*-commutativeN/A
unpow1/2N/A
lower-fma.f64N/A
unpow1/2N/A
lower-sqrt.f64N/A
*-commutativeN/A
lower-*.f64N/A
lift-log.f64N/A
metadata-eval97.5
Applied rewrites97.5%
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))