
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (- (log (- 1.0 u0))) (+ (/ cos2phi (* alphax alphax)) (/ sin2phi (* alphay alphay)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return -logf((1.0f - u0)) / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay)));
}
real(4) function code(alphax, alphay, u0, cos2phi, sin2phi)
real(4), intent (in) :: alphax
real(4), intent (in) :: alphay
real(4), intent (in) :: u0
real(4), intent (in) :: cos2phi
real(4), intent (in) :: sin2phi
code = -log((1.0e0 - u0)) / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay)))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(-log(Float32(Float32(1.0) - u0))) / Float32(Float32(cos2phi / Float32(alphax * alphax)) + Float32(sin2phi / Float32(alphay * alphay)))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = -log((single(1.0) - u0)) / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay))); end
\begin{array}{l}
\\
\frac{-\log \left(1 - u0\right)}{\frac{cos2phi}{alphax \cdot alphax} + \frac{sin2phi}{alphay \cdot alphay}}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 8 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (- (log (- 1.0 u0))) (+ (/ cos2phi (* alphax alphax)) (/ sin2phi (* alphay alphay)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return -logf((1.0f - u0)) / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay)));
}
real(4) function code(alphax, alphay, u0, cos2phi, sin2phi)
real(4), intent (in) :: alphax
real(4), intent (in) :: alphay
real(4), intent (in) :: u0
real(4), intent (in) :: cos2phi
real(4), intent (in) :: sin2phi
code = -log((1.0e0 - u0)) / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay)))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(-log(Float32(Float32(1.0) - u0))) / Float32(Float32(cos2phi / Float32(alphax * alphax)) + Float32(sin2phi / Float32(alphay * alphay)))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = -log((single(1.0) - u0)) / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay))); end
\begin{array}{l}
\\
\frac{-\log \left(1 - u0\right)}{\frac{cos2phi}{alphax \cdot alphax} + \frac{sin2phi}{alphay \cdot alphay}}
\end{array}
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (- (log1p (- u0))) (+ (* (pow alphax -2.0) cos2phi) (/ (/ sin2phi alphay) alphay))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return -log1pf(-u0) / ((powf(alphax, -2.0f) * cos2phi) + ((sin2phi / alphay) / alphay));
}
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(-log1p(Float32(-u0))) / Float32(Float32((alphax ^ Float32(-2.0)) * cos2phi) + Float32(Float32(sin2phi / alphay) / alphay))) end
\begin{array}{l}
\\
\frac{-\mathsf{log1p}\left(-u0\right)}{{alphax}^{-2} \cdot cos2phi + \frac{\frac{sin2phi}{alphay}}{alphay}}
\end{array}
Initial program 58.9%
sqr-neg58.9%
sub-neg58.9%
log1p-def98.1%
sqr-neg98.1%
associate-/r*98.0%
Simplified98.0%
div-inv98.0%
*-commutative98.0%
pow298.0%
pow-flip98.1%
metadata-eval98.1%
Applied egg-rr98.1%
Final simplification98.1%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (if (<= (- 1.0 u0) 0.9990000128746033) (/ (* alphay (- alphay)) (/ sin2phi (log (- 1.0 u0)))) (/ u0 (+ (/ cos2phi (* alphax alphax)) (/ sin2phi (* alphay alphay))))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
float tmp;
if ((1.0f - u0) <= 0.9990000128746033f) {
tmp = (alphay * -alphay) / (sin2phi / logf((1.0f - u0)));
} else {
tmp = u0 / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay)));
}
return tmp;
}
real(4) function code(alphax, alphay, u0, cos2phi, sin2phi)
real(4), intent (in) :: alphax
real(4), intent (in) :: alphay
real(4), intent (in) :: u0
real(4), intent (in) :: cos2phi
real(4), intent (in) :: sin2phi
real(4) :: tmp
if ((1.0e0 - u0) <= 0.9990000128746033e0) then
tmp = (alphay * -alphay) / (sin2phi / log((1.0e0 - u0)))
else
tmp = u0 / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay)))
end if
code = tmp
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) tmp = Float32(0.0) if (Float32(Float32(1.0) - u0) <= Float32(0.9990000128746033)) tmp = Float32(Float32(alphay * Float32(-alphay)) / Float32(sin2phi / log(Float32(Float32(1.0) - u0)))); else tmp = Float32(u0 / Float32(Float32(cos2phi / Float32(alphax * alphax)) + Float32(sin2phi / Float32(alphay * alphay)))); end return tmp end
function tmp_2 = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = single(0.0); if ((single(1.0) - u0) <= single(0.9990000128746033)) tmp = (alphay * -alphay) / (sin2phi / log((single(1.0) - u0))); else tmp = u0 / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay))); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;1 - u0 \leq 0.9990000128746033:\\
\;\;\;\;\frac{alphay \cdot \left(-alphay\right)}{\frac{sin2phi}{\log \left(1 - u0\right)}}\\
\mathbf{else}:\\
\;\;\;\;\frac{u0}{\frac{cos2phi}{alphax \cdot alphax} + \frac{sin2phi}{alphay \cdot alphay}}\\
\end{array}
\end{array}
if (-.f32 1 u0) < 0.999000013Initial program 89.9%
Taylor expanded in cos2phi around 0 72.1%
associate-/l*72.3%
associate-*r/72.3%
neg-mul-172.3%
Simplified72.3%
unpow272.3%
Applied egg-rr72.3%
if 0.999000013 < (-.f32 1 u0) Initial program 44.3%
Taylor expanded in u0 around 0 89.0%
mul-1-neg89.0%
Simplified89.0%
Final simplification83.7%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (- (log1p (- u0))) (+ (/ cos2phi (* alphax alphax)) (/ sin2phi (* alphay alphay)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return -log1pf(-u0) / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay)));
}
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(-log1p(Float32(-u0))) / Float32(Float32(cos2phi / Float32(alphax * alphax)) + Float32(sin2phi / Float32(alphay * alphay)))) end
\begin{array}{l}
\\
\frac{-\mathsf{log1p}\left(-u0\right)}{\frac{cos2phi}{alphax \cdot alphax} + \frac{sin2phi}{alphay \cdot alphay}}
\end{array}
Initial program 58.9%
sub-neg58.9%
log1p-def98.1%
Simplified98.1%
Final simplification98.1%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (- (log1p (- u0))) (+ (/ (/ sin2phi alphay) alphay) (/ (/ cos2phi alphax) alphax))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return -log1pf(-u0) / (((sin2phi / alphay) / alphay) + ((cos2phi / alphax) / alphax));
}
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(-log1p(Float32(-u0))) / Float32(Float32(Float32(sin2phi / alphay) / alphay) + Float32(Float32(cos2phi / alphax) / alphax))) end
\begin{array}{l}
\\
\frac{-\mathsf{log1p}\left(-u0\right)}{\frac{\frac{sin2phi}{alphay}}{alphay} + \frac{\frac{cos2phi}{alphax}}{alphax}}
\end{array}
Initial program 58.9%
sqr-neg58.9%
sub-neg58.9%
log1p-def98.1%
sqr-neg98.1%
associate-/r*98.0%
Simplified98.0%
add-sqr-sqrt97.9%
times-frac97.8%
Applied egg-rr97.8%
unpow297.8%
Simplified97.8%
unpow297.8%
times-frac97.9%
add-sqr-sqrt98.0%
associate-/r*98.1%
Applied egg-rr98.1%
Final simplification98.1%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ u0 (+ (/ cos2phi (* alphax alphax)) (/ sin2phi (* alphay alphay)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return u0 / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay)));
}
real(4) function code(alphax, alphay, u0, cos2phi, sin2phi)
real(4), intent (in) :: alphax
real(4), intent (in) :: alphay
real(4), intent (in) :: u0
real(4), intent (in) :: cos2phi
real(4), intent (in) :: sin2phi
code = u0 / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay)))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(u0 / Float32(Float32(cos2phi / Float32(alphax * alphax)) + Float32(sin2phi / Float32(alphay * alphay)))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = u0 / ((cos2phi / (alphax * alphax)) + (sin2phi / (alphay * alphay))); end
\begin{array}{l}
\\
\frac{u0}{\frac{cos2phi}{alphax \cdot alphax} + \frac{sin2phi}{alphay \cdot alphay}}
\end{array}
Initial program 58.9%
Taylor expanded in u0 around 0 75.0%
mul-1-neg75.0%
Simplified75.0%
Final simplification75.0%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* (/ 1.0 sin2phi) (* alphay (* u0 alphay))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (1.0f / sin2phi) * (alphay * (u0 * alphay));
}
real(4) function code(alphax, alphay, u0, cos2phi, sin2phi)
real(4), intent (in) :: alphax
real(4), intent (in) :: alphay
real(4), intent (in) :: u0
real(4), intent (in) :: cos2phi
real(4), intent (in) :: sin2phi
code = (1.0e0 / sin2phi) * (alphay * (u0 * alphay))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(Float32(1.0) / sin2phi) * Float32(alphay * Float32(u0 * alphay))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = (single(1.0) / sin2phi) * (alphay * (u0 * alphay)); end
\begin{array}{l}
\\
\frac{1}{sin2phi} \cdot \left(alphay \cdot \left(u0 \cdot alphay\right)\right)
\end{array}
Initial program 58.9%
Taylor expanded in u0 around 0 75.0%
mul-1-neg75.0%
Simplified75.0%
Taylor expanded in cos2phi around 0 57.3%
associate-/l*56.9%
*-un-lft-identity56.9%
div-inv56.8%
times-frac57.2%
Applied egg-rr57.2%
div-inv57.2%
unpow257.2%
associate-*l*57.3%
remove-double-div57.4%
Applied egg-rr57.4%
Final simplification57.4%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* alphay (* u0 (/ alphay sin2phi))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return alphay * (u0 * (alphay / sin2phi));
}
real(4) function code(alphax, alphay, u0, cos2phi, sin2phi)
real(4), intent (in) :: alphax
real(4), intent (in) :: alphay
real(4), intent (in) :: u0
real(4), intent (in) :: cos2phi
real(4), intent (in) :: sin2phi
code = alphay * (u0 * (alphay / sin2phi))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(alphay * Float32(u0 * Float32(alphay / sin2phi))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = alphay * (u0 * (alphay / sin2phi)); end
\begin{array}{l}
\\
alphay \cdot \left(u0 \cdot \frac{alphay}{sin2phi}\right)
\end{array}
Initial program 58.9%
Taylor expanded in u0 around 0 75.0%
mul-1-neg75.0%
Simplified75.0%
Taylor expanded in cos2phi around 0 57.3%
associate-/l*56.9%
unpow256.9%
*-un-lft-identity56.9%
times-frac56.9%
/-rgt-identity56.9%
Applied egg-rr56.9%
associate-/r/57.2%
Applied egg-rr57.2%
Final simplification57.2%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* alphay (* alphay (/ u0 sin2phi))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return alphay * (alphay * (u0 / sin2phi));
}
real(4) function code(alphax, alphay, u0, cos2phi, sin2phi)
real(4), intent (in) :: alphax
real(4), intent (in) :: alphay
real(4), intent (in) :: u0
real(4), intent (in) :: cos2phi
real(4), intent (in) :: sin2phi
code = alphay * (alphay * (u0 / sin2phi))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(alphay * Float32(alphay * Float32(u0 / sin2phi))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = alphay * (alphay * (u0 / sin2phi)); end
\begin{array}{l}
\\
alphay \cdot \left(alphay \cdot \frac{u0}{sin2phi}\right)
\end{array}
Initial program 58.9%
Taylor expanded in u0 around 0 75.0%
mul-1-neg75.0%
Simplified75.0%
Taylor expanded in cos2phi around 0 57.3%
associate-/l*56.9%
unpow256.9%
*-un-lft-identity56.9%
times-frac56.9%
/-rgt-identity56.9%
Applied egg-rr56.9%
div-inv56.8%
*-commutative56.8%
clear-num57.3%
Applied egg-rr57.3%
Final simplification57.3%
herbie shell --seed 2023336
(FPCore (alphax alphay u0 cos2phi sin2phi)
:name "Beckmann Distribution sample, tan2theta, alphax != alphay, u1 <= 0.5"
:precision binary32
:pre (and (and (and (and (and (<= 0.0001 alphax) (<= alphax 1.0)) (and (<= 0.0001 alphay) (<= alphay 1.0))) (and (<= 2.328306437e-10 u0) (<= u0 1.0))) (and (<= 0.0 cos2phi) (<= cos2phi 1.0))) (<= 0.0 sin2phi))
(/ (- (log (- 1.0 u0))) (+ (/ cos2phi (* alphax alphax)) (/ sin2phi (* alphay alphay)))))