
(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 9 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 (* (sqrt (- (log1p (- u1)))) (sin (* 2.0 (cbrt (* (pow PI 3.0) (pow u2 3.0)))))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-log1pf(-u1)) * sinf((2.0f * cbrtf((powf(((float) M_PI), 3.0f) * powf(u2, 3.0f)))));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * sin(Float32(Float32(2.0) * cbrt(Float32((Float32(pi) ^ Float32(3.0)) * (u2 ^ Float32(3.0))))))) end
\begin{array}{l}
\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \sin \left(2 \cdot \sqrt[3]{{\pi}^{3} \cdot {u2}^{3}}\right)
\end{array}
Initial program 58.8%
sub-neg58.8%
log1p-def98.3%
associate-*l*98.3%
Simplified98.3%
add-cbrt-cube98.3%
add-cbrt-cube98.3%
cbrt-unprod98.3%
pow398.3%
pow398.3%
Applied egg-rr98.3%
Final simplification98.3%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log1p (- u1)))) (log1p (expm1 (sin (* 2.0 (* PI u2)))))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-log1pf(-u1)) * log1pf(expm1f(sinf((2.0f * (((float) M_PI) * u2)))));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * log1p(expm1(sin(Float32(Float32(2.0) * Float32(Float32(pi) * u2)))))) end
\begin{array}{l}
\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \mathsf{log1p}\left(\mathsf{expm1}\left(\sin \left(2 \cdot \left(\pi \cdot u2\right)\right)\right)\right)
\end{array}
Initial program 58.8%
sub-neg58.8%
log1p-def98.3%
associate-*l*98.3%
Simplified98.3%
add-cbrt-cube98.3%
add-cbrt-cube98.3%
cbrt-unprod98.3%
pow398.3%
pow398.3%
Applied egg-rr98.3%
cbrt-prod98.3%
unpow398.3%
add-cbrt-cube98.3%
unpow398.3%
add-cbrt-cube98.3%
pow198.3%
metadata-eval98.3%
pow-pow94.4%
log1p-expm1-u94.3%
pow-pow98.3%
metadata-eval98.3%
pow198.3%
Applied egg-rr98.3%
Final simplification98.3%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* u2 (* 2.0 PI))))
(if (<= t_0 0.0015999999595806003)
(* (sqrt (- (log1p (- u1)))) t_0)
(* (sin (* 2.0 (* PI u2))) (sqrt (+ u1 (* 0.5 (* u1 u1))))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = u2 * (2.0f * ((float) M_PI));
float tmp;
if (t_0 <= 0.0015999999595806003f) {
tmp = sqrtf(-log1pf(-u1)) * t_0;
} else {
tmp = sinf((2.0f * (((float) M_PI) * u2))) * sqrtf((u1 + (0.5f * (u1 * u1))));
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = Float32(u2 * Float32(Float32(2.0) * Float32(pi))) tmp = Float32(0.0) if (t_0 <= Float32(0.0015999999595806003)) tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * t_0); else tmp = Float32(sin(Float32(Float32(2.0) * Float32(Float32(pi) * u2))) * sqrt(Float32(u1 + Float32(Float32(0.5) * Float32(u1 * u1))))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := u2 \cdot \left(2 \cdot \pi\right)\\
\mathbf{if}\;t_0 \leq 0.0015999999595806003:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot t_0\\
\mathbf{else}:\\
\;\;\;\;\sin \left(2 \cdot \left(\pi \cdot u2\right)\right) \cdot \sqrt{u1 + 0.5 \cdot \left(u1 \cdot u1\right)}\\
\end{array}
\end{array}
if (*.f32 (*.f32 2 (PI.f32)) u2) < 0.00159999996Initial program 61.8%
sub-neg61.8%
log1p-def98.3%
associate-*l*98.3%
Simplified98.3%
add-cbrt-cube98.3%
add-cbrt-cube98.3%
cbrt-unprod98.3%
pow398.3%
pow398.4%
Applied egg-rr98.4%
Taylor expanded in u2 around 0 98.0%
associate-*r*98.0%
*-commutative98.0%
associate-*r*98.0%
Simplified98.0%
if 0.00159999996 < (*.f32 (*.f32 2 (PI.f32)) u2) Initial program 54.0%
associate-*r*54.0%
add-cbrt-cube54.0%
pow1/353.6%
pow353.5%
Applied egg-rr53.5%
Taylor expanded in u1 around 0 87.2%
+-commutative87.2%
mul-1-neg87.2%
unsub-neg87.2%
unpow287.2%
associate-*r*87.2%
Simplified87.2%
Taylor expanded in u2 around inf 87.2%
*-commutative87.2%
unpow1/387.8%
rem-cbrt-cube87.8%
cancel-sign-sub-inv87.8%
metadata-eval87.8%
unpow287.8%
Simplified87.8%
Final simplification94.2%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* u2 (* 2.0 PI))))
(if (<= t_0 0.014999999664723873)
(* (sqrt (- (log1p (- u1)))) t_0)
(* (sqrt u1) (sin t_0)))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = u2 * (2.0f * ((float) M_PI));
float tmp;
if (t_0 <= 0.014999999664723873f) {
tmp = sqrtf(-log1pf(-u1)) * t_0;
} else {
tmp = sqrtf(u1) * sinf(t_0);
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = Float32(u2 * Float32(Float32(2.0) * Float32(pi))) tmp = Float32(0.0) if (t_0 <= Float32(0.014999999664723873)) tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * t_0); else tmp = Float32(sqrt(u1) * sin(t_0)); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := u2 \cdot \left(2 \cdot \pi\right)\\
\mathbf{if}\;t_0 \leq 0.014999999664723873:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot t_0\\
\mathbf{else}:\\
\;\;\;\;\sqrt{u1} \cdot \sin t_0\\
\end{array}
\end{array}
if (*.f32 (*.f32 2 (PI.f32)) u2) < 0.0149999997Initial program 61.0%
sub-neg61.0%
log1p-def98.3%
associate-*l*98.3%
Simplified98.3%
add-cbrt-cube98.3%
add-cbrt-cube98.3%
cbrt-unprod98.3%
pow398.3%
pow398.4%
Applied egg-rr98.4%
Taylor expanded in u2 around 0 96.2%
associate-*r*96.2%
*-commutative96.2%
associate-*r*96.2%
Simplified96.2%
if 0.0149999997 < (*.f32 (*.f32 2 (PI.f32)) u2) Initial program 53.6%
Taylor expanded in u1 around 0 79.0%
mul-1-neg79.0%
Simplified79.0%
Taylor expanded in u2 around inf 79.0%
*-commutative79.0%
*-commutative79.0%
associate-*r*79.0%
*-commutative79.0%
*-commutative79.0%
*-commutative79.0%
Simplified79.0%
Final simplification91.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log1p (- u1)))) (sin (* 2.0 (* PI u2)))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-log1pf(-u1)) * sinf((2.0f * (((float) M_PI) * u2)));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * sin(Float32(Float32(2.0) * Float32(Float32(pi) * u2)))) end
\begin{array}{l}
\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \sin \left(2 \cdot \left(\pi \cdot u2\right)\right)
\end{array}
Initial program 58.8%
sub-neg58.8%
log1p-def98.3%
associate-*l*98.3%
Simplified98.3%
Final simplification98.3%
(FPCore (cosTheta_i u1 u2) :precision binary32 (if (<= u2 0.0002500000118743628) (* 2.0 (* PI (* u2 (sqrt (+ u1 (* 0.5 (* u1 u1))))))) (* (sqrt u1) (sin (* u2 (* 2.0 PI))))))
float code(float cosTheta_i, float u1, float u2) {
float tmp;
if (u2 <= 0.0002500000118743628f) {
tmp = 2.0f * (((float) M_PI) * (u2 * sqrtf((u1 + (0.5f * (u1 * u1))))));
} else {
tmp = sqrtf(u1) * sinf((u2 * (2.0f * ((float) M_PI))));
}
return tmp;
}
function code(cosTheta_i, u1, u2) tmp = Float32(0.0) if (u2 <= Float32(0.0002500000118743628)) tmp = Float32(Float32(2.0) * Float32(Float32(pi) * Float32(u2 * sqrt(Float32(u1 + Float32(Float32(0.5) * Float32(u1 * u1))))))); else tmp = Float32(sqrt(u1) * sin(Float32(u2 * Float32(Float32(2.0) * Float32(pi))))); end return tmp end
function tmp_2 = code(cosTheta_i, u1, u2) tmp = single(0.0); if (u2 <= single(0.0002500000118743628)) tmp = single(2.0) * (single(pi) * (u2 * sqrt((u1 + (single(0.5) * (u1 * u1)))))); else tmp = sqrt(u1) * sin((u2 * (single(2.0) * single(pi)))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;u2 \leq 0.0002500000118743628:\\
\;\;\;\;2 \cdot \left(\pi \cdot \left(u2 \cdot \sqrt{u1 + 0.5 \cdot \left(u1 \cdot u1\right)}\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\sqrt{u1} \cdot \sin \left(u2 \cdot \left(2 \cdot \pi\right)\right)\\
\end{array}
\end{array}
if u2 < 2.50000012e-4Initial program 61.8%
associate-*r*61.8%
add-cbrt-cube61.8%
pow1/361.0%
pow361.0%
Applied egg-rr61.0%
Taylor expanded in u1 around 0 81.9%
+-commutative81.9%
mul-1-neg81.9%
unsub-neg81.9%
unpow281.9%
associate-*r*81.9%
Simplified81.9%
Taylor expanded in u2 around 0 85.5%
associate-*r*85.6%
*-commutative85.6%
*-commutative85.6%
cancel-sign-sub-inv85.6%
metadata-eval85.6%
unpow285.6%
Simplified85.6%
if 2.50000012e-4 < u2 Initial program 54.0%
Taylor expanded in u1 around 0 78.4%
mul-1-neg78.4%
Simplified78.4%
Taylor expanded in u2 around inf 78.4%
*-commutative78.4%
*-commutative78.4%
associate-*r*78.4%
*-commutative78.4%
*-commutative78.4%
*-commutative78.4%
Simplified78.4%
Final simplification82.8%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* 2.0 (* PI (* u2 (sqrt (+ u1 (* 0.5 (* u1 u1))))))))
float code(float cosTheta_i, float u1, float u2) {
return 2.0f * (((float) M_PI) * (u2 * sqrtf((u1 + (0.5f * (u1 * u1))))));
}
function code(cosTheta_i, u1, u2) return Float32(Float32(2.0) * Float32(Float32(pi) * Float32(u2 * sqrt(Float32(u1 + Float32(Float32(0.5) * Float32(u1 * u1))))))) end
function tmp = code(cosTheta_i, u1, u2) tmp = single(2.0) * (single(pi) * (u2 * sqrt((u1 + (single(0.5) * (u1 * u1)))))); end
\begin{array}{l}
\\
2 \cdot \left(\pi \cdot \left(u2 \cdot \sqrt{u1 + 0.5 \cdot \left(u1 \cdot u1\right)}\right)\right)
\end{array}
Initial program 58.8%
associate-*r*58.8%
add-cbrt-cube58.8%
pow1/358.2%
pow358.2%
Applied egg-rr58.2%
Taylor expanded in u1 around 0 83.9%
+-commutative83.9%
mul-1-neg83.9%
unsub-neg83.9%
unpow283.9%
associate-*r*83.9%
Simplified83.9%
Taylor expanded in u2 around 0 72.2%
associate-*r*72.2%
*-commutative72.2%
*-commutative72.2%
cancel-sign-sub-inv72.2%
metadata-eval72.2%
unpow272.2%
Simplified72.2%
Final simplification72.2%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (* 2.0 u2) (* PI (sqrt u1))))
float code(float cosTheta_i, float u1, float u2) {
return (2.0f * u2) * (((float) M_PI) * sqrtf(u1));
}
function code(cosTheta_i, u1, u2) return Float32(Float32(Float32(2.0) * u2) * Float32(Float32(pi) * sqrt(u1))) end
function tmp = code(cosTheta_i, u1, u2) tmp = (single(2.0) * u2) * (single(pi) * sqrt(u1)); end
\begin{array}{l}
\\
\left(2 \cdot u2\right) \cdot \left(\pi \cdot \sqrt{u1}\right)
\end{array}
Initial program 58.8%
Taylor expanded in u1 around 0 75.5%
mul-1-neg75.5%
Simplified75.5%
Taylor expanded in u2 around 0 64.2%
associate-*l*64.2%
associate-*r*64.2%
Simplified64.2%
Final simplification64.2%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (* u2 (* 2.0 PI)) (sqrt u1)))
float code(float cosTheta_i, float u1, float u2) {
return (u2 * (2.0f * ((float) M_PI))) * sqrtf(u1);
}
function code(cosTheta_i, u1, u2) return Float32(Float32(u2 * Float32(Float32(2.0) * Float32(pi))) * sqrt(u1)) end
function tmp = code(cosTheta_i, u1, u2) tmp = (u2 * (single(2.0) * single(pi))) * sqrt(u1); end
\begin{array}{l}
\\
\left(u2 \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{u1}
\end{array}
Initial program 58.8%
Taylor expanded in u1 around 0 75.5%
mul-1-neg75.5%
Simplified75.5%
Taylor expanded in u2 around 0 64.2%
associate-*r*64.2%
associate-*r*64.2%
*-commutative64.2%
associate-*r*64.2%
Simplified64.2%
Final simplification64.2%
herbie shell --seed 2023185
(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))))