
(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 8 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 (cos (* PI (+ u2 u2))) (* (sqrt (- (log u1))) (* 0.16666666666666666 (sqrt 2.0))) 0.5))
double code(double u1, double u2) {
return fma(cos((((double) M_PI) * (u2 + u2))), (sqrt(-log(u1)) * (0.16666666666666666 * sqrt(2.0))), 0.5);
}
function code(u1, u2) return fma(cos(Float64(pi * Float64(u2 + u2))), Float64(sqrt(Float64(-log(u1))) * Float64(0.16666666666666666 * sqrt(2.0))), 0.5) end
code[u1_, u2_] := N[(N[Cos[N[(Pi * N[(u2 + u2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[(N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] * N[(0.16666666666666666 * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\cos \left(\pi \cdot \left(u2 + u2\right)\right), \sqrt{-\log u1} \cdot \left(0.16666666666666666 \cdot \sqrt{2}\right), 0.5\right)
\end{array}
Initial program 99.4%
lift-+.f64N/A
lift-*.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-*l*N/A
lift-pow.f64N/A
sqr-powN/A
associate-*l*N/A
lower-fma.f64N/A
Applied rewrites99.1%
Taylor expanded in u1 around inf
+-commutativeN/A
associate-*r*N/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.5%
Taylor expanded in u1 around inf
+-commutativeN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.6%
Applied rewrites99.6%
(FPCore (u1 u2) :precision binary64 (fma (* 0.16666666666666666 (sqrt (* -2.0 (log u1)))) (cos (* PI (+ u2 u2))) 0.5))
double code(double u1, double u2) {
return fma((0.16666666666666666 * sqrt((-2.0 * log(u1)))), cos((((double) M_PI) * (u2 + u2))), 0.5);
}
function code(u1, u2) return fma(Float64(0.16666666666666666 * sqrt(Float64(-2.0 * log(u1)))), cos(Float64(pi * Float64(u2 + u2))), 0.5) end
code[u1_, u2_] := N[(N[(0.16666666666666666 * N[Sqrt[N[(-2.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[Cos[N[(Pi * N[(u2 + u2), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(0.16666666666666666 \cdot \sqrt{-2 \cdot \log u1}, \cos \left(\pi \cdot \left(u2 + u2\right)\right), 0.5\right)
\end{array}
Initial program 99.4%
lift-+.f64N/A
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.4%
lift-fma.f64N/A
Applied rewrites99.4%
(FPCore (u1 u2) :precision binary64 (fma (fma (* u2 u2) (* -2.0 (* PI PI)) 1.0) (* (sqrt (- (log u1))) (* 0.16666666666666666 (sqrt 2.0))) 0.5))
double code(double u1, double u2) {
return fma(fma((u2 * u2), (-2.0 * (((double) M_PI) * ((double) M_PI))), 1.0), (sqrt(-log(u1)) * (0.16666666666666666 * sqrt(2.0))), 0.5);
}
function code(u1, u2) return fma(fma(Float64(u2 * u2), Float64(-2.0 * Float64(pi * pi)), 1.0), Float64(sqrt(Float64(-log(u1))) * Float64(0.16666666666666666 * sqrt(2.0))), 0.5) end
code[u1_, u2_] := N[(N[(N[(u2 * u2), $MachinePrecision] * N[(-2.0 * N[(Pi * Pi), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision] * N[(N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] * N[(0.16666666666666666 * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\mathsf{fma}\left(u2 \cdot u2, -2 \cdot \left(\pi \cdot \pi\right), 1\right), \sqrt{-\log u1} \cdot \left(0.16666666666666666 \cdot \sqrt{2}\right), 0.5\right)
\end{array}
Initial program 99.4%
lift-+.f64N/A
lift-*.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-*l*N/A
lift-pow.f64N/A
sqr-powN/A
associate-*l*N/A
lower-fma.f64N/A
Applied rewrites99.1%
Taylor expanded in u1 around inf
+-commutativeN/A
associate-*r*N/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.5%
Taylor expanded in u1 around inf
+-commutativeN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.6%
Taylor expanded in u2 around 0
Applied rewrites98.1%
(FPCore (u1 u2) :precision binary64 (fma (sqrt (- (log u1))) (* (sqrt 2.0) (fma (* u2 u2) (* (* PI PI) -0.3333333333333333) 0.16666666666666666)) 0.5))
double code(double u1, double u2) {
return fma(sqrt(-log(u1)), (sqrt(2.0) * fma((u2 * u2), ((((double) M_PI) * ((double) M_PI)) * -0.3333333333333333), 0.16666666666666666)), 0.5);
}
function code(u1, u2) return fma(sqrt(Float64(-log(u1))), Float64(sqrt(2.0) * fma(Float64(u2 * u2), Float64(Float64(pi * pi) * -0.3333333333333333), 0.16666666666666666)), 0.5) end
code[u1_, u2_] := N[(N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] * N[(N[Sqrt[2.0], $MachinePrecision] * N[(N[(u2 * u2), $MachinePrecision] * N[(N[(Pi * Pi), $MachinePrecision] * -0.3333333333333333), $MachinePrecision] + 0.16666666666666666), $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{-\log u1}, \sqrt{2} \cdot \mathsf{fma}\left(u2 \cdot u2, \left(\pi \cdot \pi\right) \cdot -0.3333333333333333, 0.16666666666666666\right), 0.5\right)
\end{array}
Initial program 99.4%
lift-+.f64N/A
lift-*.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-*l*N/A
lift-pow.f64N/A
sqr-powN/A
associate-*l*N/A
lower-fma.f64N/A
Applied rewrites99.1%
Taylor expanded in u1 around inf
+-commutativeN/A
associate-*r*N/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.5%
Taylor expanded in u2 around 0
Applied rewrites98.1%
Final simplification98.1%
(FPCore (u1 u2) :precision binary64 (fma (* 0.16666666666666666 (fma u2 (* u2 (* -2.0 (* PI PI))) 1.0)) (sqrt (* (log u1) (- 2.0))) 0.5))
double code(double u1, double u2) {
return fma((0.16666666666666666 * fma(u2, (u2 * (-2.0 * (((double) M_PI) * ((double) M_PI)))), 1.0)), sqrt((log(u1) * -2.0)), 0.5);
}
function code(u1, u2) return fma(Float64(0.16666666666666666 * fma(u2, Float64(u2 * Float64(-2.0 * Float64(pi * pi))), 1.0)), sqrt(Float64(log(u1) * Float64(-2.0))), 0.5) end
code[u1_, u2_] := N[(N[(0.16666666666666666 * N[(u2 * N[(u2 * N[(-2.0 * N[(Pi * Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + 1.0), $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(N[Log[u1], $MachinePrecision] * (-2.0)), $MachinePrecision]], $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(0.16666666666666666 \cdot \mathsf{fma}\left(u2, u2 \cdot \left(-2 \cdot \left(\pi \cdot \pi\right)\right), 1\right), \sqrt{\log u1 \cdot \left(-2\right)}, 0.5\right)
\end{array}
Initial program 99.4%
Taylor expanded in u1 around inf
lower-*.f64N/A
lower-sqrt.f64N/A
log-recN/A
lower-neg.f64N/A
lower-log.f64N/A
lower-sqrt.f6499.4
Applied rewrites99.4%
Taylor expanded in u2 around 0
+-commutativeN/A
rem-square-sqrtN/A
unpow2N/A
*-commutativeN/A
associate-*r*N/A
unpow2N/A
rem-square-sqrtN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
*-commutativeN/A
rem-square-sqrtN/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
lower-PI.f64N/A
lower-PI.f64N/A
unpow2N/A
rem-square-sqrt98.0
Applied rewrites98.0%
lift-+.f64N/A
Applied rewrites97.9%
Final simplification97.9%
(FPCore (u1 u2) :precision binary64 (fma (sqrt (- (log u1))) (* 0.16666666666666666 (sqrt 2.0)) 0.5))
double code(double u1, double u2) {
return fma(sqrt(-log(u1)), (0.16666666666666666 * sqrt(2.0)), 0.5);
}
function code(u1, u2) return fma(sqrt(Float64(-log(u1))), Float64(0.16666666666666666 * sqrt(2.0)), 0.5) end
code[u1_, u2_] := N[(N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] * N[(0.16666666666666666 * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{-\log u1}, 0.16666666666666666 \cdot \sqrt{2}, 0.5\right)
\end{array}
Initial program 99.4%
lift-+.f64N/A
lift-*.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-*l*N/A
lift-pow.f64N/A
sqr-powN/A
associate-*l*N/A
lower-fma.f64N/A
Applied rewrites99.1%
Taylor expanded in u1 around inf
+-commutativeN/A
associate-*r*N/A
*-commutativeN/A
lower-fma.f64N/A
Applied rewrites99.5%
Taylor expanded in u2 around 0
Applied rewrites97.4%
(FPCore (u1 u2) :precision binary64 (fma (* (sqrt (- (log u1))) (sqrt 2.0)) 0.16666666666666666 0.5))
double code(double u1, double u2) {
return fma((sqrt(-log(u1)) * sqrt(2.0)), 0.16666666666666666, 0.5);
}
function code(u1, u2) return fma(Float64(sqrt(Float64(-log(u1))) * sqrt(2.0)), 0.16666666666666666, 0.5) end
code[u1_, u2_] := N[(N[(N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * 0.16666666666666666 + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{-\log u1} \cdot \sqrt{2}, 0.16666666666666666, 0.5\right)
\end{array}
Initial program 99.4%
Taylor expanded in u2 around 0
+-commutativeN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
lower-fma.f64N/A
lower-sqrt.f64N/A
lower-log.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f640.0
Applied rewrites0.0%
Applied rewrites97.3%
Applied rewrites96.4%
Taylor expanded in u1 around inf
Applied rewrites97.3%
Final simplification97.3%
(FPCore (u1 u2) :precision binary64 (fma (sqrt (* -2.0 (log u1))) 0.16666666666666666 0.5))
double code(double u1, double u2) {
return fma(sqrt((-2.0 * log(u1))), 0.16666666666666666, 0.5);
}
function code(u1, u2) return fma(sqrt(Float64(-2.0 * log(u1))), 0.16666666666666666, 0.5) end
code[u1_, u2_] := N[(N[Sqrt[N[(-2.0 * N[Log[u1], $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * 0.16666666666666666 + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{-2 \cdot \log u1}, 0.16666666666666666, 0.5\right)
\end{array}
Initial program 99.4%
Taylor expanded in u2 around 0
+-commutativeN/A
*-commutativeN/A
associate-*l*N/A
*-commutativeN/A
lower-fma.f64N/A
lower-sqrt.f64N/A
lower-log.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f640.0
Applied rewrites0.0%
Applied rewrites97.3%
herbie shell --seed 2024222
(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))