
(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 10 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))) (+ (/ (* alphax sin2phi) alphay) (/ (* alphay cos2phi) alphax))) (* alphax alphay)))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (-log1pf(-u0) / (((alphax * sin2phi) / alphay) + ((alphay * cos2phi) / alphax))) * (alphax * alphay);
}
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(Float32(-log1p(Float32(-u0))) / Float32(Float32(Float32(alphax * sin2phi) / alphay) + Float32(Float32(alphay * cos2phi) / alphax))) * Float32(alphax * alphay)) end
\begin{array}{l}
\\
\frac{-\mathsf{log1p}\left(-u0\right)}{\frac{alphax \cdot sin2phi}{alphay} + \frac{alphay \cdot cos2phi}{alphax}} \cdot \left(alphax \cdot alphay\right)
\end{array}
Initial program 64.2%
sub-neg64.2%
log1p-def98.1%
Simplified98.1%
associate-/r*98.1%
associate-/r*98.1%
frac-add97.7%
Applied egg-rr97.7%
+-commutative97.7%
*-commutative97.7%
*-commutative97.7%
fma-def97.8%
Simplified97.8%
associate-/r/98.3%
associate-*r/98.3%
Applied egg-rr98.3%
Taylor expanded in sin2phi around 0 98.7%
Final simplification98.7%
(FPCore (alphax alphay u0 cos2phi sin2phi)
:precision binary32
(if (<= (/ sin2phi (* alphay alphay)) 0.012000000104308128)
(/
u0
(- (/ cos2phi (* alphax alphax)) (* (/ sin2phi alphay) (/ -1.0 alphay))))
(* (* alphax alphay) (* (/ (log1p (- u0)) sin2phi) (/ (- alphay) alphax)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
float tmp;
if ((sin2phi / (alphay * alphay)) <= 0.012000000104308128f) {
tmp = u0 / ((cos2phi / (alphax * alphax)) - ((sin2phi / alphay) * (-1.0f / alphay)));
} else {
tmp = (alphax * alphay) * ((log1pf(-u0) / sin2phi) * (-alphay / alphax));
}
return tmp;
}
function code(alphax, alphay, u0, cos2phi, sin2phi) tmp = Float32(0.0) if (Float32(sin2phi / Float32(alphay * alphay)) <= Float32(0.012000000104308128)) tmp = Float32(u0 / Float32(Float32(cos2phi / Float32(alphax * alphax)) - Float32(Float32(sin2phi / alphay) * Float32(Float32(-1.0) / alphay)))); else tmp = Float32(Float32(alphax * alphay) * Float32(Float32(log1p(Float32(-u0)) / sin2phi) * Float32(Float32(-alphay) / alphax))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\frac{sin2phi}{alphay \cdot alphay} \leq 0.012000000104308128:\\
\;\;\;\;\frac{u0}{\frac{cos2phi}{alphax \cdot alphax} - \frac{sin2phi}{alphay} \cdot \frac{-1}{alphay}}\\
\mathbf{else}:\\
\;\;\;\;\left(alphax \cdot alphay\right) \cdot \left(\frac{\mathsf{log1p}\left(-u0\right)}{sin2phi} \cdot \frac{-alphay}{alphax}\right)\\
\end{array}
\end{array}
if (/.f32 sin2phi (*.f32 alphay alphay)) < 0.0120000001Initial program 60.2%
Taylor expanded in u0 around 0 71.0%
mul-1-neg71.0%
Simplified71.0%
associate-/r*71.1%
div-inv71.1%
Applied egg-rr71.1%
if 0.0120000001 < (/.f32 sin2phi (*.f32 alphay alphay)) Initial program 66.8%
sub-neg66.8%
log1p-def97.6%
Simplified97.6%
associate-/r*97.6%
associate-/r*97.7%
frac-add97.4%
Applied egg-rr97.4%
+-commutative97.4%
*-commutative97.4%
*-commutative97.4%
fma-def97.4%
Simplified97.4%
associate-/r/98.2%
associate-*r/98.2%
Applied egg-rr98.2%
Taylor expanded in sin2phi around inf 66.9%
mul-1-neg66.9%
times-frac67.0%
distribute-rgt-neg-in67.0%
sub-neg67.0%
log1p-def97.3%
Simplified97.3%
Final simplification87.2%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* (* alphax alphay) (/ (- (log1p (- u0))) (+ (* alphax (/ sin2phi alphay)) (/ alphay (/ alphax cos2phi))))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (alphax * alphay) * (-log1pf(-u0) / ((alphax * (sin2phi / alphay)) + (alphay / (alphax / cos2phi))));
}
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(alphax * alphay) * Float32(Float32(-log1p(Float32(-u0))) / Float32(Float32(alphax * Float32(sin2phi / alphay)) + Float32(alphay / Float32(alphax / cos2phi))))) end
\begin{array}{l}
\\
\left(alphax \cdot alphay\right) \cdot \frac{-\mathsf{log1p}\left(-u0\right)}{alphax \cdot \frac{sin2phi}{alphay} + \frac{alphay}{\frac{alphax}{cos2phi}}}
\end{array}
Initial program 64.2%
sub-neg64.2%
log1p-def98.1%
Simplified98.1%
associate-/r*98.1%
associate-/r*98.1%
frac-add97.7%
Applied egg-rr97.7%
+-commutative97.7%
*-commutative97.7%
*-commutative97.7%
fma-def97.8%
Simplified97.8%
associate-/r/98.3%
associate-*r/98.3%
Applied egg-rr98.3%
fma-udef98.3%
associate-/l*98.2%
Applied egg-rr98.2%
Final simplification98.2%
(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 64.2%
sub-neg64.2%
log1p-def98.1%
Simplified98.1%
Final simplification98.1%
(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(Float32(sin2phi / alphay) / alphay))) end
\begin{array}{l}
\\
\frac{-\mathsf{log1p}\left(-u0\right)}{\frac{cos2phi}{alphax \cdot alphax} + \frac{\frac{sin2phi}{alphay}}{alphay}}
\end{array}
Initial program 64.2%
sub-neg64.2%
log1p-def98.1%
Simplified98.1%
clear-num75.7%
associate-/r/75.6%
pow275.6%
pow-flip75.7%
metadata-eval75.7%
Applied egg-rr98.2%
*-commutative75.7%
metadata-eval75.7%
pow-flip75.6%
pow275.6%
div-inv75.6%
associate-/r*75.7%
Applied egg-rr98.1%
Final simplification98.1%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* (* alphax alphay) (/ u0 (+ (/ (* alphax sin2phi) alphay) (/ (* alphay cos2phi) alphax)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (alphax * alphay) * (u0 / (((alphax * sin2phi) / alphay) + ((alphay * cos2phi) / alphax)));
}
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 = (alphax * alphay) * (u0 / (((alphax * sin2phi) / alphay) + ((alphay * cos2phi) / alphax)))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(alphax * alphay) * Float32(u0 / Float32(Float32(Float32(alphax * sin2phi) / alphay) + Float32(Float32(alphay * cos2phi) / alphax)))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = (alphax * alphay) * (u0 / (((alphax * sin2phi) / alphay) + ((alphay * cos2phi) / alphax))); end
\begin{array}{l}
\\
\left(alphax \cdot alphay\right) \cdot \frac{u0}{\frac{alphax \cdot sin2phi}{alphay} + \frac{alphay \cdot cos2phi}{alphax}}
\end{array}
Initial program 64.2%
sub-neg64.2%
log1p-def98.1%
Simplified98.1%
associate-/r*98.1%
associate-/r*98.1%
frac-add97.7%
Applied egg-rr97.7%
+-commutative97.7%
*-commutative97.7%
*-commutative97.7%
fma-def97.8%
Simplified97.8%
associate-/r/98.3%
associate-*r/98.3%
Applied egg-rr98.3%
Taylor expanded in u0 around 0 76.1%
Final simplification76.1%
(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 64.2%
Taylor expanded in u0 around 0 75.6%
mul-1-neg75.6%
Simplified75.6%
Final simplification75.6%
(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(Float32(sin2phi / 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{\frac{sin2phi}{alphay}}{alphay}}
\end{array}
Initial program 64.2%
Taylor expanded in u0 around 0 75.6%
mul-1-neg75.6%
Simplified75.6%
clear-num75.7%
associate-/r/75.6%
pow275.6%
pow-flip75.7%
metadata-eval75.7%
Applied egg-rr75.7%
*-commutative75.7%
metadata-eval75.7%
pow-flip75.6%
pow275.6%
div-inv75.6%
associate-/r*75.7%
Applied egg-rr75.7%
Final simplification75.7%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* (* alphax alphay) (* (/ alphay alphax) (/ u0 sin2phi))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (alphax * alphay) * ((alphay / alphax) * (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 = (alphax * alphay) * ((alphay / alphax) * (u0 / sin2phi))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(alphax * alphay) * Float32(Float32(alphay / alphax) * Float32(u0 / sin2phi))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = (alphax * alphay) * ((alphay / alphax) * (u0 / sin2phi)); end
\begin{array}{l}
\\
\left(alphax \cdot alphay\right) \cdot \left(\frac{alphay}{alphax} \cdot \frac{u0}{sin2phi}\right)
\end{array}
Initial program 64.2%
sub-neg64.2%
log1p-def98.1%
Simplified98.1%
associate-/r*98.1%
associate-/r*98.1%
frac-add97.7%
Applied egg-rr97.7%
+-commutative97.7%
*-commutative97.7%
*-commutative97.7%
fma-def97.8%
Simplified97.8%
associate-/r/98.3%
associate-*r/98.3%
Applied egg-rr98.3%
Taylor expanded in sin2phi around inf 75.0%
Taylor expanded in u0 around 0 60.7%
times-frac60.7%
Simplified60.7%
Final simplification60.7%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* (* alphax alphay) (* (/ alphay sin2phi) (/ u0 alphax))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (alphax * alphay) * ((alphay / sin2phi) * (u0 / alphax));
}
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 = (alphax * alphay) * ((alphay / sin2phi) * (u0 / alphax))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(alphax * alphay) * Float32(Float32(alphay / sin2phi) * Float32(u0 / alphax))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = (alphax * alphay) * ((alphay / sin2phi) * (u0 / alphax)); end
\begin{array}{l}
\\
\left(alphax \cdot alphay\right) \cdot \left(\frac{alphay}{sin2phi} \cdot \frac{u0}{alphax}\right)
\end{array}
Initial program 64.2%
sub-neg64.2%
log1p-def98.1%
Simplified98.1%
associate-/r*98.1%
associate-/r*98.1%
frac-add97.7%
Applied egg-rr97.7%
+-commutative97.7%
*-commutative97.7%
*-commutative97.7%
fma-def97.8%
Simplified97.8%
associate-/r/98.3%
associate-*r/98.3%
Applied egg-rr98.3%
Taylor expanded in sin2phi around inf 75.0%
Taylor expanded in u0 around 0 60.7%
*-commutative60.7%
times-frac60.7%
Simplified60.7%
Final simplification60.7%
herbie shell --seed 2024041
(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)))))