
(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 7 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))) (+ (/ cos2phi (* alphax alphax)) (* (pow alphay -2.0) sin2phi))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return -log1pf(-u0) / ((cos2phi / (alphax * alphax)) + (powf(alphay, -2.0f) * sin2phi));
}
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(-log1p(Float32(-u0))) / Float32(Float32(cos2phi / Float32(alphax * alphax)) + Float32((alphay ^ Float32(-2.0)) * sin2phi))) end
\begin{array}{l}
\\
\frac{-\mathsf{log1p}\left(-u0\right)}{\frac{cos2phi}{alphax \cdot alphax} + {alphay}^{-2} \cdot sin2phi}
\end{array}
Initial program 63.4%
sub-neg63.4%
log1p-def98.2%
Simplified98.2%
clear-num98.1%
associate-/r/98.1%
pow298.1%
pow-flip98.3%
metadata-eval98.3%
Applied egg-rr98.3%
Final simplification98.3%
(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 63.4%
sub-neg63.4%
log1p-def98.2%
Simplified98.2%
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(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 63.4%
sub-neg63.4%
log1p-def98.2%
Simplified98.2%
clear-num98.1%
associate-/r/98.1%
pow298.1%
pow-flip98.3%
metadata-eval98.3%
Applied egg-rr98.3%
*-commutative98.3%
metadata-eval98.3%
pow-flip98.1%
div-inv98.2%
pow298.2%
associate-/r*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(Float32(cos2phi / alphax) / alphax) + Float32(sin2phi / Float32(alphay * alphay)))) end
\begin{array}{l}
\\
\frac{-\mathsf{log1p}\left(-u0\right)}{\frac{\frac{cos2phi}{alphax}}{alphax} + \frac{sin2phi}{alphay \cdot alphay}}
\end{array}
Initial program 63.4%
sub-neg63.4%
log1p-def98.2%
Simplified98.2%
associate-/r*98.2%
div-inv98.2%
Applied egg-rr98.2%
un-div-inv98.2%
Applied egg-rr98.2%
Final simplification98.2%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* (log1p (- u0)) (* alphay (/ (- alphay) sin2phi))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return log1pf(-u0) * (alphay * (-alphay / sin2phi));
}
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(log1p(Float32(-u0)) * Float32(alphay * Float32(Float32(-alphay) / sin2phi))) end
\begin{array}{l}
\\
\mathsf{log1p}\left(-u0\right) \cdot \left(alphay \cdot \frac{-alphay}{sin2phi}\right)
\end{array}
Initial program 63.4%
sub-neg63.4%
log1p-def98.2%
Simplified98.2%
clear-num98.1%
associate-/r/98.1%
pow298.1%
pow-flip98.3%
metadata-eval98.3%
Applied egg-rr98.3%
Applied egg-rr98.1%
Taylor expanded in cos2phi around 0 74.9%
pow257.8%
*-un-lft-identity57.8%
times-frac57.8%
Applied egg-rr75.1%
Final simplification75.1%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* u0 (/ (pow alphay 2.0) sin2phi)))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return u0 * (powf(alphay, 2.0f) / 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 = u0 * ((alphay ** 2.0e0) / sin2phi)
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(u0 * Float32((alphay ^ Float32(2.0)) / sin2phi)) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = u0 * ((alphay ^ single(2.0)) / sin2phi); end
\begin{array}{l}
\\
u0 \cdot \frac{{alphay}^{2}}{sin2phi}
\end{array}
Initial program 63.4%
sub-neg63.4%
log1p-def98.2%
Simplified98.2%
Taylor expanded in cos2phi around 0 53.0%
mul-1-neg53.0%
associate-/l*52.8%
distribute-neg-frac52.8%
sub-neg52.8%
log1p-def74.4%
Simplified74.4%
Taylor expanded in u0 around 0 57.8%
associate-/l*57.3%
associate-/r/57.8%
Simplified57.8%
Final simplification57.8%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (* u0 (* alphay (/ alphay sin2phi))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return u0 * (alphay * (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 = u0 * (alphay * (alphay / sin2phi))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(u0 * Float32(alphay * Float32(alphay / sin2phi))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = u0 * (alphay * (alphay / sin2phi)); end
\begin{array}{l}
\\
u0 \cdot \left(alphay \cdot \frac{alphay}{sin2phi}\right)
\end{array}
Initial program 63.4%
sub-neg63.4%
log1p-def98.2%
Simplified98.2%
Taylor expanded in cos2phi around 0 53.0%
mul-1-neg53.0%
associate-/l*52.8%
distribute-neg-frac52.8%
sub-neg52.8%
log1p-def74.4%
Simplified74.4%
Taylor expanded in u0 around 0 57.8%
associate-/l*57.3%
associate-/r/57.8%
Simplified57.8%
pow257.8%
*-un-lft-identity57.8%
times-frac57.8%
Applied egg-rr57.8%
Final simplification57.8%
herbie shell --seed 2024026
(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)))))