
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (sin (* (* 2.0 PI) u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-logf((1.0f - u1))) * sinf(((2.0f * ((float) M_PI)) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log(Float32(Float32(1.0) - u1)))) * sin(Float32(Float32(Float32(2.0) * Float32(pi)) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(-log((single(1.0) - u1))) * sin(((single(2.0) * single(pi)) * u2)); end
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \sin \left(\left(2 \cdot \pi\right) \cdot u2\right)
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 11 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (sin (* (* 2.0 PI) u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-logf((1.0f - u1))) * sinf(((2.0f * ((float) M_PI)) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log(Float32(Float32(1.0) - u1)))) * sin(Float32(Float32(Float32(2.0) * Float32(pi)) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(-log((single(1.0) - u1))) * sin(((single(2.0) * single(pi)) * u2)); end
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \sin \left(\left(2 \cdot \pi\right) \cdot u2\right)
\end{array}
(FPCore (cosTheta_i u1 u2) :precision binary32 (cbrt (* (pow (sin (* PI (* 2.0 u2))) 3.0) (pow (- (log1p (- u1))) 1.5))))
float code(float cosTheta_i, float u1, float u2) {
return cbrtf((powf(sinf((((float) M_PI) * (2.0f * u2))), 3.0f) * powf(-log1pf(-u1), 1.5f)));
}
function code(cosTheta_i, u1, u2) return cbrt(Float32((sin(Float32(Float32(pi) * Float32(Float32(2.0) * u2))) ^ Float32(3.0)) * (Float32(-log1p(Float32(-u1))) ^ Float32(1.5)))) end
\begin{array}{l}
\\
\sqrt[3]{{\sin \left(\pi \cdot \left(2 \cdot u2\right)\right)}^{3} \cdot {\left(-\mathsf{log1p}\left(-u1\right)\right)}^{1.5}}
\end{array}
Initial program 58.3%
add-exp-log57.7%
associate-*l*57.7%
Applied egg-rr57.7%
*-commutative57.7%
rem-exp-log58.3%
*-commutative58.3%
associate-*r*58.3%
*-commutative58.3%
add-cbrt-cube58.3%
add-cbrt-cube58.3%
cbrt-unprod58.3%
Applied egg-rr98.5%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sin (* PI (* 2.0 u2))) (sqrt (- (log1p (- u1))))))
float code(float cosTheta_i, float u1, float u2) {
return sinf((((float) M_PI) * (2.0f * u2))) * sqrtf(-log1pf(-u1));
}
function code(cosTheta_i, u1, u2) return Float32(sin(Float32(Float32(pi) * Float32(Float32(2.0) * u2))) * sqrt(Float32(-log1p(Float32(-u1))))) end
\begin{array}{l}
\\
\sin \left(\pi \cdot \left(2 \cdot u2\right)\right) \cdot \sqrt{-\mathsf{log1p}\left(-u1\right)}
\end{array}
Initial program 58.3%
sub-neg58.3%
log1p-define98.3%
*-commutative98.3%
associate-*l*98.3%
Simplified98.3%
Final simplification98.3%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (* u1 (+ 1.0 (* u1 (- 0.5 (* u1 (- (* u1 -0.25) 0.3333333333333333))))))) (sin (* u2 (* PI 2.0)))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 * (1.0f + (u1 * (0.5f - (u1 * ((u1 * -0.25f) - 0.3333333333333333f))))))) * sinf((u2 * (((float) M_PI) * 2.0f)));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(Float32(0.5) - Float32(u1 * Float32(Float32(u1 * Float32(-0.25)) - Float32(0.3333333333333333)))))))) * sin(Float32(u2 * Float32(Float32(pi) * Float32(2.0))))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 * (single(1.0) + (u1 * (single(0.5) - (u1 * ((u1 * single(-0.25)) - single(0.3333333333333333)))))))) * sin((u2 * (single(pi) * single(2.0)))); end
\begin{array}{l}
\\
\sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 - u1 \cdot \left(u1 \cdot -0.25 - 0.3333333333333333\right)\right)\right)} \cdot \sin \left(u2 \cdot \left(\pi \cdot 2\right)\right)
\end{array}
Initial program 58.3%
Taylor expanded in u1 around 0 91.7%
Final simplification91.7%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sin (* u2 (* PI 2.0))) (sqrt (* u1 (+ 1.0 (* u1 (- 0.5 (* u1 -0.3333333333333333))))))))
float code(float cosTheta_i, float u1, float u2) {
return sinf((u2 * (((float) M_PI) * 2.0f))) * sqrtf((u1 * (1.0f + (u1 * (0.5f - (u1 * -0.3333333333333333f))))));
}
function code(cosTheta_i, u1, u2) return Float32(sin(Float32(u2 * Float32(Float32(pi) * Float32(2.0)))) * sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(Float32(0.5) - Float32(u1 * Float32(-0.3333333333333333)))))))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sin((u2 * (single(pi) * single(2.0)))) * sqrt((u1 * (single(1.0) + (u1 * (single(0.5) - (u1 * single(-0.3333333333333333))))))); end
\begin{array}{l}
\\
\sin \left(u2 \cdot \left(\pi \cdot 2\right)\right) \cdot \sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 - u1 \cdot -0.3333333333333333\right)\right)}
\end{array}
Initial program 58.3%
Taylor expanded in u1 around 0 89.8%
Final simplification89.8%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sin (* u2 (* PI 2.0))) (sqrt (* u1 (- 1.0 (* u1 -0.5))))))
float code(float cosTheta_i, float u1, float u2) {
return sinf((u2 * (((float) M_PI) * 2.0f))) * sqrtf((u1 * (1.0f - (u1 * -0.5f))));
}
function code(cosTheta_i, u1, u2) return Float32(sin(Float32(u2 * Float32(Float32(pi) * Float32(2.0)))) * sqrt(Float32(u1 * Float32(Float32(1.0) - Float32(u1 * Float32(-0.5)))))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sin((u2 * (single(pi) * single(2.0)))) * sqrt((u1 * (single(1.0) - (u1 * single(-0.5))))); end
\begin{array}{l}
\\
\sin \left(u2 \cdot \left(\pi \cdot 2\right)\right) \cdot \sqrt{u1 \cdot \left(1 - u1 \cdot -0.5\right)}
\end{array}
Initial program 58.3%
Taylor expanded in u1 around 0 86.3%
Final simplification86.3%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sin (/ 1.0 (/ 1.0 (* PI (* 2.0 u2))))) (sqrt u1)))
float code(float cosTheta_i, float u1, float u2) {
return sinf((1.0f / (1.0f / (((float) M_PI) * (2.0f * u2))))) * sqrtf(u1);
}
function code(cosTheta_i, u1, u2) return Float32(sin(Float32(Float32(1.0) / Float32(Float32(1.0) / Float32(Float32(pi) * Float32(Float32(2.0) * u2))))) * sqrt(u1)) end
function tmp = code(cosTheta_i, u1, u2) tmp = sin((single(1.0) / (single(1.0) / (single(pi) * (single(2.0) * u2))))) * sqrt(u1); end
\begin{array}{l}
\\
\sin \left(\frac{1}{\frac{1}{\pi \cdot \left(2 \cdot u2\right)}}\right) \cdot \sqrt{u1}
\end{array}
Initial program 58.3%
add-exp-log57.7%
associate-*l*57.7%
Applied egg-rr57.7%
rem-exp-log58.3%
*-commutative58.3%
pow158.3%
metadata-eval58.3%
pow-div58.3%
pow158.3%
clear-num58.3%
pow158.3%
pow-div58.3%
metadata-eval58.3%
inv-pow58.3%
associate-*r*58.3%
*-commutative58.3%
Applied egg-rr58.3%
Taylor expanded in u1 around 0 75.4%
mul-1-neg75.4%
Simplified75.4%
Final simplification75.4%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sin (* u2 (* PI 2.0))) (sqrt u1)))
float code(float cosTheta_i, float u1, float u2) {
return sinf((u2 * (((float) M_PI) * 2.0f))) * sqrtf(u1);
}
function code(cosTheta_i, u1, u2) return Float32(sin(Float32(u2 * Float32(Float32(pi) * Float32(2.0)))) * sqrt(u1)) end
function tmp = code(cosTheta_i, u1, u2) tmp = sin((u2 * (single(pi) * single(2.0)))) * sqrt(u1); end
\begin{array}{l}
\\
\sin \left(u2 \cdot \left(\pi \cdot 2\right)\right) \cdot \sqrt{u1}
\end{array}
Initial program 58.3%
sub-neg58.3%
log1p-define98.3%
*-commutative98.3%
associate-*l*98.3%
Simplified98.3%
add-cbrt-cube98.4%
pow1/395.8%
Applied egg-rr71.8%
unpow1/373.4%
Simplified73.4%
Taylor expanded in u1 around 0 75.4%
*-commutative75.4%
associate-*r*75.4%
Simplified75.4%
Final simplification75.4%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* 2.0 (* PI (* u2 (sqrt u1)))))
float code(float cosTheta_i, float u1, float u2) {
return 2.0f * (((float) M_PI) * (u2 * sqrtf(u1)));
}
function code(cosTheta_i, u1, u2) return Float32(Float32(2.0) * Float32(Float32(pi) * Float32(u2 * sqrt(u1)))) end
function tmp = code(cosTheta_i, u1, u2) tmp = single(2.0) * (single(pi) * (u2 * sqrt(u1))); end
\begin{array}{l}
\\
2 \cdot \left(\pi \cdot \left(u2 \cdot \sqrt{u1}\right)\right)
\end{array}
Initial program 58.3%
sub-neg58.3%
log1p-define98.3%
*-commutative98.3%
associate-*l*98.3%
Simplified98.3%
add-cbrt-cube98.4%
pow1/395.8%
Applied egg-rr71.8%
unpow1/373.4%
Simplified73.4%
Taylor expanded in u1 around 0 75.3%
Taylor expanded in u2 around 0 62.8%
associate-*r*62.8%
*-commutative62.8%
Simplified62.8%
Final simplification62.8%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* 2.0 (* (sqrt u1) (* PI u2))))
float code(float cosTheta_i, float u1, float u2) {
return 2.0f * (sqrtf(u1) * (((float) M_PI) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(Float32(2.0) * Float32(sqrt(u1) * Float32(Float32(pi) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = single(2.0) * (sqrt(u1) * (single(pi) * u2)); end
\begin{array}{l}
\\
2 \cdot \left(\sqrt{u1} \cdot \left(\pi \cdot u2\right)\right)
\end{array}
Initial program 58.3%
sub-neg58.3%
log1p-define98.3%
*-commutative98.3%
associate-*l*98.3%
Simplified98.3%
add-cbrt-cube98.4%
pow1/395.8%
Applied egg-rr71.8%
unpow1/373.4%
Simplified73.4%
Taylor expanded in u1 around 0 75.3%
Taylor expanded in u2 around 0 62.8%
Final simplification62.8%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (* PI (* u2 (sqrt u1))) -2.0))
float code(float cosTheta_i, float u1, float u2) {
return (((float) M_PI) * (u2 * sqrtf(u1))) * -2.0f;
}
function code(cosTheta_i, u1, u2) return Float32(Float32(Float32(pi) * Float32(u2 * sqrt(u1))) * Float32(-2.0)) end
function tmp = code(cosTheta_i, u1, u2) tmp = (single(pi) * (u2 * sqrt(u1))) * single(-2.0); end
\begin{array}{l}
\\
\left(\pi \cdot \left(u2 \cdot \sqrt{u1}\right)\right) \cdot -2
\end{array}
Initial program 58.3%
Taylor expanded in u1 around 0 -0.0%
*-commutative-0.0%
unpow2-0.0%
rem-square-sqrt4.0%
*-commutative4.0%
neg-mul-14.0%
*-commutative4.0%
Simplified4.0%
Taylor expanded in u2 around 0 4.6%
add04.6%
*-commutative4.6%
Applied egg-rr4.6%
add04.6%
associate-*l*4.6%
*-commutative4.6%
associate-*l*4.6%
Simplified4.6%
Final simplification4.6%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (* (sqrt u1) (* PI u2)) -2.0))
float code(float cosTheta_i, float u1, float u2) {
return (sqrtf(u1) * (((float) M_PI) * u2)) * -2.0f;
}
function code(cosTheta_i, u1, u2) return Float32(Float32(sqrt(u1) * Float32(Float32(pi) * u2)) * Float32(-2.0)) end
function tmp = code(cosTheta_i, u1, u2) tmp = (sqrt(u1) * (single(pi) * u2)) * single(-2.0); end
\begin{array}{l}
\\
\left(\sqrt{u1} \cdot \left(\pi \cdot u2\right)\right) \cdot -2
\end{array}
Initial program 58.3%
Taylor expanded in u1 around 0 -0.0%
*-commutative-0.0%
unpow2-0.0%
rem-square-sqrt4.0%
*-commutative4.0%
neg-mul-14.0%
*-commutative4.0%
Simplified4.0%
Taylor expanded in u2 around 0 4.6%
Final simplification4.6%
herbie shell --seed 2024107
(FPCore (cosTheta_i u1 u2)
:name "Beckmann Sample, near normal, slope_y"
:precision binary32
:pre (and (and (and (> cosTheta_i 0.9999) (<= cosTheta_i 1.0)) (and (<= 2.328306437e-10 u1) (<= u1 1.0))) (and (<= 2.328306437e-10 u2) (<= u2 1.0)))
(* (sqrt (- (log (- 1.0 u1)))) (sin (* (* 2.0 PI) u2))))