
(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 5 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)) (/ 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 62.0%
sub-neg62.0%
log1p-def98.8%
Simplified98.8%
Final simplification98.8%
(FPCore (alphax alphay u0 cos2phi sin2phi)
:precision binary32
(let* ((t_0 (/ sin2phi (* alphay alphay))))
(if (<= t_0 0.4000000059604645)
(/ u0 (+ (/ cos2phi (* alphax alphax)) t_0))
(/ (- (pow alphay 2.0)) (- (* sin2phi 0.5) (/ sin2phi u0))))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
float t_0 = sin2phi / (alphay * alphay);
float tmp;
if (t_0 <= 0.4000000059604645f) {
tmp = u0 / ((cos2phi / (alphax * alphax)) + t_0);
} else {
tmp = -powf(alphay, 2.0f) / ((sin2phi * 0.5f) - (sin2phi / u0));
}
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) :: t_0
real(4) :: tmp
t_0 = sin2phi / (alphay * alphay)
if (t_0 <= 0.4000000059604645e0) then
tmp = u0 / ((cos2phi / (alphax * alphax)) + t_0)
else
tmp = -(alphay ** 2.0e0) / ((sin2phi * 0.5e0) - (sin2phi / u0))
end if
code = tmp
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) t_0 = Float32(sin2phi / Float32(alphay * alphay)) tmp = Float32(0.0) if (t_0 <= Float32(0.4000000059604645)) tmp = Float32(u0 / Float32(Float32(cos2phi / Float32(alphax * alphax)) + t_0)); else tmp = Float32(Float32(-(alphay ^ Float32(2.0))) / Float32(Float32(sin2phi * Float32(0.5)) - Float32(sin2phi / u0))); end return tmp end
function tmp_2 = code(alphax, alphay, u0, cos2phi, sin2phi) t_0 = sin2phi / (alphay * alphay); tmp = single(0.0); if (t_0 <= single(0.4000000059604645)) tmp = u0 / ((cos2phi / (alphax * alphax)) + t_0); else tmp = -(alphay ^ single(2.0)) / ((sin2phi * single(0.5)) - (sin2phi / u0)); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{sin2phi}{alphay \cdot alphay}\\
\mathbf{if}\;t_0 \leq 0.4000000059604645:\\
\;\;\;\;\frac{u0}{\frac{cos2phi}{alphax \cdot alphax} + t_0}\\
\mathbf{else}:\\
\;\;\;\;\frac{-{alphay}^{2}}{sin2phi \cdot 0.5 - \frac{sin2phi}{u0}}\\
\end{array}
\end{array}
if (/.f32 sin2phi (*.f32 alphay alphay)) < 0.400000006Initial program 59.3%
sub-neg59.3%
log1p-def98.9%
Simplified98.9%
associate-/r*98.7%
div-inv98.6%
Applied egg-rr98.6%
Taylor expanded in u0 around 0 72.1%
mul-1-neg72.1%
Simplified72.1%
*-commutative72.1%
clear-num72.1%
frac-times72.2%
*-un-lft-identity72.2%
Applied egg-rr72.2%
if 0.400000006 < (/.f32 sin2phi (*.f32 alphay alphay)) Initial program 64.4%
sub-neg64.4%
log1p-def98.7%
Simplified98.7%
Taylor expanded in cos2phi around 0 64.9%
mul-1-neg64.9%
associate-/l*64.6%
distribute-neg-frac64.6%
sub-neg64.6%
log1p-def97.6%
Simplified97.6%
Taylor expanded in u0 around 0 91.3%
+-commutative91.3%
mul-1-neg91.3%
unsub-neg91.3%
*-commutative91.3%
Simplified91.3%
Final simplification82.3%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ u0 (+ (/ sin2phi (* alphay alphay)) (/ (/ cos2phi alphax) alphax))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return u0 / ((sin2phi / (alphay * alphay)) + ((cos2phi / alphax) / 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 = u0 / ((sin2phi / (alphay * alphay)) + ((cos2phi / alphax) / alphax))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(u0 / Float32(Float32(sin2phi / Float32(alphay * alphay)) + Float32(Float32(cos2phi / alphax) / alphax))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = u0 / ((sin2phi / (alphay * alphay)) + ((cos2phi / alphax) / alphax)); end
\begin{array}{l}
\\
\frac{u0}{\frac{sin2phi}{alphay \cdot alphay} + \frac{\frac{cos2phi}{alphax}}{alphax}}
\end{array}
Initial program 62.0%
sub-neg62.0%
log1p-def98.8%
Simplified98.8%
associate-/r*98.7%
div-inv98.7%
Applied egg-rr98.7%
Taylor expanded in u0 around 0 76.5%
mul-1-neg76.5%
Simplified76.5%
un-div-inv76.6%
Applied egg-rr76.6%
Final simplification76.6%
(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(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 62.0%
sub-neg62.0%
log1p-def98.8%
Simplified98.8%
associate-/r*98.7%
div-inv98.7%
Applied egg-rr98.7%
Taylor expanded in u0 around 0 76.5%
mul-1-neg76.5%
Simplified76.5%
*-commutative76.5%
clear-num76.5%
frac-times76.6%
*-un-lft-identity76.6%
Applied egg-rr76.6%
Final simplification76.6%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (* u0 (* alphax alphax)) cos2phi))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (u0 * (alphax * alphax)) / cos2phi;
}
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 * (alphax * alphax)) / cos2phi
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(u0 * Float32(alphax * alphax)) / cos2phi) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = (u0 * (alphax * alphax)) / cos2phi; end
\begin{array}{l}
\\
\frac{u0 \cdot \left(alphax \cdot alphax\right)}{cos2phi}
\end{array}
Initial program 62.0%
sub-neg62.0%
log1p-def98.8%
Simplified98.8%
associate-/r*98.7%
div-inv98.7%
Applied egg-rr98.7%
Taylor expanded in u0 around 0 76.5%
mul-1-neg76.5%
Simplified76.5%
Taylor expanded in cos2phi around inf 25.1%
pow225.1%
Applied egg-rr25.1%
Final simplification25.1%
herbie shell --seed 2023334
(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)))))