
(FPCore (u1 u2) :precision binary64 (+ (* (* (/ 1.0 6.0) (pow (* -2.0 (log u1)) 0.5)) (cos (* (* 2.0 (PI)) u2))) 0.5))
\begin{array}{l}
\\
\left(\frac{1}{6} \cdot {\left(-2 \cdot \log u1\right)}^{0.5}\right) \cdot \cos \left(\left(2 \cdot \mathsf{PI}\left(\right)\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))
\begin{array}{l}
\\
\left(\frac{1}{6} \cdot {\left(-2 \cdot \log u1\right)}^{0.5}\right) \cdot \cos \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right) + 0.5
\end{array}
(FPCore (u1 u2) :precision binary64 (+ (* (cos (* u2 (* (cbrt (* (* (PI) (PI)) (PI))) 2.0))) (* (* (sqrt (- (log u1))) (sqrt 2.0)) (/ 1.0 6.0))) 0.5))
\begin{array}{l}
\\
\cos \left(u2 \cdot \left(\sqrt[3]{\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \mathsf{PI}\left(\right)} \cdot 2\right)\right) \cdot \left(\left(\sqrt{-\log u1} \cdot \sqrt{2}\right) \cdot \frac{1}{6}\right) + 0.5
\end{array}
Initial program 99.4%
Taylor expanded in u1 around inf
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
log-recN/A
lower-neg.f64N/A
lower-log.f6499.5
Applied rewrites99.5%
lift-PI.f64N/A
add-cbrt-cubeN/A
lower-cbrt.f64N/A
rem-cube-cbrtN/A
add-cbrt-cubeN/A
lift-PI.f64N/A
lower-pow.f6499.5
Applied rewrites99.5%
lift-pow.f64N/A
unpow3N/A
lower-*.f64N/A
lower-*.f6499.5
Applied rewrites99.5%
Final simplification99.5%
(FPCore (u1 u2) :precision binary64 (+ (* (cos (* (* (PI) 2.0) u2)) (* 0.16666666666666666 (* (sqrt (- (log u1))) (sqrt 2.0)))) 0.5))
\begin{array}{l}
\\
\cos \left(\left(\mathsf{PI}\left(\right) \cdot 2\right) \cdot u2\right) \cdot \left(0.16666666666666666 \cdot \left(\sqrt{-\log u1} \cdot \sqrt{2}\right)\right) + 0.5
\end{array}
Initial program 99.4%
Taylor expanded in u1 around inf
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
log-recN/A
lower-neg.f64N/A
lower-log.f6499.5
Applied rewrites99.5%
lift-/.f64N/A
metadata-eval99.5
Applied rewrites99.5%
Final simplification99.5%
(FPCore (u1 u2) :precision binary64 (fma (* (* 0.16666666666666666 (sqrt (- (log u1)))) (cos (* (* (PI) 2.0) u2))) (sqrt 2.0) 0.5))
\begin{array}{l}
\\
\mathsf{fma}\left(\left(0.16666666666666666 \cdot \sqrt{-\log u1}\right) \cdot \cos \left(\left(\mathsf{PI}\left(\right) \cdot 2\right) \cdot u2\right), \sqrt{2}, 0.5\right)
\end{array}
Initial program 99.4%
lift-pow.f64N/A
sqr-powN/A
pow2N/A
lower-pow.f64N/A
metadata-evalN/A
metadata-evalN/A
lower-pow.f64N/A
lift-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
metadata-eval99.0
Applied rewrites99.0%
lift-/.f64N/A
metadata-eval99.0
Applied rewrites99.0%
metadata-evalN/A
lift-+.f64N/A
lift-*.f64N/A
lift-*.f64N/A
lift-pow.f64N/A
lift-pow.f64N/A
pow-powN/A
metadata-evalN/A
pow1/2N/A
lift-sqrt.f64N/A
*-commutativeN/A
lift-*.f64N/A
Applied rewrites99.4%
metadata-evalN/A
lift-fma.f64N/A
Applied rewrites99.5%
Final simplification99.5%
(FPCore (u1 u2) :precision binary64 (fma (* (sqrt (* (log u1) -2.0)) 0.16666666666666666) (cos (* (* (PI) 2.0) u2)) 0.5))
\begin{array}{l}
\\
\mathsf{fma}\left(\sqrt{\log u1 \cdot -2} \cdot 0.16666666666666666, \cos \left(\left(\mathsf{PI}\left(\right) \cdot 2\right) \cdot u2\right), 0.5\right)
\end{array}
Initial program 99.4%
lift-+.f64N/A
lift-*.f64N/A
lower-fma.f6499.4
lift-/.f64N/A
metadata-eval99.4
lift-pow.f64N/A
unpow1/2N/A
lower-sqrt.f6499.4
lift-*.f64N/A
*-commutativeN/A
lower-*.f6499.4
lift-*.f64N/A
*-commutativeN/A
lower-*.f6499.4
lift-*.f64N/A
*-commutativeN/A
lower-*.f6499.4
Applied rewrites99.4%
Final simplification99.4%
(FPCore (u1 u2) :precision binary64 (+ (* (fma (* (* (PI) (PI)) -2.0) (* u2 u2) 1.0) (* (* (sqrt (- (log u1))) (sqrt 2.0)) (/ 1.0 6.0))) 0.5))
\begin{array}{l}
\\
\mathsf{fma}\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot -2, u2 \cdot u2, 1\right) \cdot \left(\left(\sqrt{-\log u1} \cdot \sqrt{2}\right) \cdot \frac{1}{6}\right) + 0.5
\end{array}
Initial program 99.4%
Taylor expanded in u1 around inf
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
log-recN/A
lower-neg.f64N/A
lower-log.f6499.5
Applied rewrites99.5%
Taylor expanded in u2 around 0
+-commutativeN/A
*-commutativeN/A
rem-square-sqrtN/A
unpow2N/A
associate-*r*N/A
unpow2N/A
rem-square-sqrtN/A
*-commutativeN/A
*-commutativeN/A
lower-fma.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-sqrtN/A
unpow2N/A
lower-*.f6498.8
Applied rewrites98.8%
Final simplification98.8%
(FPCore (u1 u2) :precision binary64 (+ (* (* (* 0.16666666666666666 (sqrt (- (log u1)))) (sqrt 2.0)) (fma (* (* (PI) (PI)) -2.0) (* u2 u2) 1.0)) 0.5))
\begin{array}{l}
\\
\left(\left(0.16666666666666666 \cdot \sqrt{-\log u1}\right) \cdot \sqrt{2}\right) \cdot \mathsf{fma}\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot -2, u2 \cdot u2, 1\right) + 0.5
\end{array}
Initial program 99.4%
lift-pow.f64N/A
sqr-powN/A
pow2N/A
lower-pow.f64N/A
metadata-evalN/A
metadata-evalN/A
lower-pow.f64N/A
lift-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
metadata-eval99.0
Applied rewrites99.0%
Taylor expanded in u2 around 0
+-commutativeN/A
*-commutativeN/A
rem-square-sqrtN/A
unpow2N/A
associate-*r*N/A
unpow2N/A
rem-square-sqrtN/A
*-commutativeN/A
*-commutativeN/A
lower-fma.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-sqrtN/A
unpow2N/A
lower-*.f6498.3
Applied rewrites98.3%
lift-*.f64N/A
lift-/.f64N/A
lift-pow.f64N/A
lift-pow.f64N/A
pow-powN/A
lift-*.f64N/A
metadata-evalN/A
distribute-rgt-neg-inN/A
distribute-lft-neg-outN/A
lift-neg.f64N/A
metadata-evalN/A
pow1/2N/A
sqrt-unprodN/A
lift-sqrt.f64N/A
lift-sqrt.f64N/A
associate-*r*N/A
lower-*.f64N/A
lower-*.f64N/A
metadata-eval98.7
Applied rewrites98.7%
(FPCore (u1 u2) :precision binary64 (+ (* (* (sqrt (* (log u1) -2.0)) 0.16666666666666666) (fma (* (* (PI) (PI)) -2.0) (* u2 u2) 1.0)) 0.5))
\begin{array}{l}
\\
\left(\sqrt{\log u1 \cdot -2} \cdot 0.16666666666666666\right) \cdot \mathsf{fma}\left(\left(\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot -2, u2 \cdot u2, 1\right) + 0.5
\end{array}
Initial program 99.4%
lift-pow.f64N/A
sqr-powN/A
pow2N/A
lower-pow.f64N/A
metadata-evalN/A
metadata-evalN/A
lower-pow.f64N/A
lift-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
metadata-eval99.0
Applied rewrites99.0%
Taylor expanded in u2 around 0
+-commutativeN/A
*-commutativeN/A
rem-square-sqrtN/A
unpow2N/A
associate-*r*N/A
unpow2N/A
rem-square-sqrtN/A
*-commutativeN/A
*-commutativeN/A
lower-fma.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-sqrtN/A
unpow2N/A
lower-*.f6498.3
Applied rewrites98.3%
lift-*.f64N/A
lift-/.f64N/A
lift-pow.f64N/A
lift-pow.f64N/A
pow-powN/A
metadata-evalN/A
pow1/2N/A
lift-sqrt.f64N/A
*-commutativeN/A
lift-*.f64N/A
metadata-eval98.6
Applied rewrites98.6%
(FPCore (u1 u2) :precision binary64 (fma (* 0.16666666666666666 (sqrt 2.0)) (sqrt (- (log u1))) 0.5))
double code(double u1, double u2) {
return fma((0.16666666666666666 * sqrt(2.0)), sqrt(-log(u1)), 0.5);
}
function code(u1, u2) return fma(Float64(0.16666666666666666 * sqrt(2.0)), sqrt(Float64(-log(u1))), 0.5) end
code[u1_, u2_] := N[(N[(0.16666666666666666 * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] * N[Sqrt[(-N[Log[u1], $MachinePrecision])], $MachinePrecision] + 0.5), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(0.16666666666666666 \cdot \sqrt{2}, \sqrt{-\log u1}, 0.5\right)
\end{array}
Initial program 99.4%
Taylor expanded in u2 around 0
+-commutativeN/A
*-commutativeN/A
associate-*r*N/A
lower-fma.f64N/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-log.f640.0
Applied rewrites0.0%
Applied rewrites97.6%
Applied rewrites97.8%
Applied rewrites97.9%
(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
+-commutativeN/A
*-commutativeN/A
associate-*r*N/A
lower-fma.f64N/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-sqrt.f64N/A
lower-log.f640.0
Applied rewrites0.0%
Applied rewrites97.6%
herbie shell --seed 2024244
(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))