
(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 4 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 (* (* 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 rewrites99.6%
(FPCore (u1 u2) :precision binary64 (fma (* (sqrt (- (log u1))) 0.16666666666666666) (* (sqrt 2.0) (cos (* (* PI u2) -2.0))) 0.5))
double code(double u1, double u2) {
return fma((sqrt(-log(u1)) * 0.16666666666666666), (sqrt(2.0) * cos(((((double) M_PI) * u2) * -2.0))), 0.5);
}
function code(u1, u2) return fma(Float64(sqrt(Float64(-log(u1))) * 0.16666666666666666), Float64(sqrt(2.0) * cos(Float64(Float64(pi * u2) * -2.0))), 0.5) end
code[u1_, u2_] := N[(N[(N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] * 0.16666666666666666), $MachinePrecision] * N[(N[Sqrt[2.0], $MachinePrecision] * N[Cos[N[(N[(Pi * u2), $MachinePrecision] * -2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{-\log u1} \cdot 0.16666666666666666, \sqrt{2} \cdot \cos \left(\left(\pi \cdot u2\right) \cdot -2\right), 0.5\right)
\end{array}
Initial program 99.4%
Applied rewrites99.5%
(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 (* (log (* (log u1) -2.0)) 0.5)))
(+
(* (* (/ 1.0 6.0) (+ (cosh t_0) (sinh t_0))) (cos (* (* 2.0 PI) u2)))
0.5)))
double code(double u1, double u2) {
double t_0 = log((log(u1) * -2.0)) * 0.5;
return (((1.0 / 6.0) * (cosh(t_0) + sinh(t_0))) * cos(((2.0 * ((double) M_PI)) * u2))) + 0.5;
}
public static double code(double u1, double u2) {
double t_0 = Math.log((Math.log(u1) * -2.0)) * 0.5;
return (((1.0 / 6.0) * (Math.cosh(t_0) + Math.sinh(t_0))) * Math.cos(((2.0 * Math.PI) * u2))) + 0.5;
}
def code(u1, u2): t_0 = math.log((math.log(u1) * -2.0)) * 0.5 return (((1.0 / 6.0) * (math.cosh(t_0) + math.sinh(t_0))) * math.cos(((2.0 * math.pi) * u2))) + 0.5
function code(u1, u2) t_0 = Float64(log(Float64(log(u1) * -2.0)) * 0.5) return Float64(Float64(Float64(Float64(1.0 / 6.0) * Float64(cosh(t_0) + sinh(t_0))) * cos(Float64(Float64(2.0 * pi) * u2))) + 0.5) end
function tmp = code(u1, u2) t_0 = log((log(u1) * -2.0)) * 0.5; tmp = (((1.0 / 6.0) * (cosh(t_0) + sinh(t_0))) * cos(((2.0 * pi) * u2))) + 0.5; end
code[u1_, u2_] := Block[{t$95$0 = N[(N[Log[N[(N[Log[u1], $MachinePrecision] * -2.0), $MachinePrecision]], $MachinePrecision] * 0.5), $MachinePrecision]}, N[(N[(N[(N[(1.0 / 6.0), $MachinePrecision] * N[(N[Cosh[t$95$0], $MachinePrecision] + N[Sinh[t$95$0], $MachinePrecision]), $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 := \log \left(\log u1 \cdot -2\right) \cdot 0.5\\
\left(\frac{1}{6} \cdot \left(\cosh t\_0 + \sinh t\_0\right)\right) \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right) + 0.5
\end{array}
\end{array}
Initial program 99.4%
lift-pow.f64N/A
lift-*.f64N/A
lift-log.f64N/A
pow-to-expN/A
sinh-+-cosh-revN/A
lower-+.f64N/A
lower-cosh.f64N/A
lower-*.f64N/A
lower-log.f64N/A
*-commutativeN/A
lower-*.f64N/A
lift-log.f64N/A
lower-sinh.f64N/A
lower-*.f64N/A
lower-log.f64N/A
*-commutativeN/A
lower-*.f64N/A
lift-log.f6499.0
Applied rewrites99.0%
herbie shell --seed 2025057
(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))