
(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)) (- (- (* cos2phi (pow alphax -2.0))) (/ (/ sin2phi alphay) alphay))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return log1pf(-u0) / (-(cos2phi * powf(alphax, -2.0f)) - ((sin2phi / alphay) / alphay));
}
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(log1p(Float32(-u0)) / Float32(Float32(-Float32(cos2phi * (alphax ^ Float32(-2.0)))) - Float32(Float32(sin2phi / alphay) / alphay))) end
\begin{array}{l}
\\
\frac{\mathsf{log1p}\left(-u0\right)}{\left(-cos2phi \cdot {alphax}^{-2}\right) - \frac{\frac{sin2phi}{alphay}}{alphay}}
\end{array}
Initial program 63.6%
distribute-frac-neg63.6%
distribute-neg-frac263.6%
sub-neg63.6%
log1p-define98.5%
neg-sub098.5%
associate--r+98.5%
neg-sub098.5%
associate-/r*98.5%
distribute-neg-frac298.5%
Simplified98.5%
associate-/r*98.7%
div-inv98.6%
Applied egg-rr98.6%
associate-*r/98.7%
*-rgt-identity98.7%
Simplified98.7%
distribute-frac-neg298.7%
associate-/r*98.6%
div-inv98.6%
distribute-lft-neg-in98.6%
pow298.6%
pow-flip98.7%
metadata-eval98.7%
Applied egg-rr98.7%
Final simplification98.7%
(FPCore (alphax alphay u0 cos2phi sin2phi)
:precision binary32
(if (<= u0 0.05249999836087227)
(/
(* u0 (- 1.0 (* u0 (- (* u0 (- (* u0 -0.25) 0.3333333333333333)) 0.5))))
(+ (/ (/ sin2phi alphay) alphay) (/ cos2phi (* alphax alphax))))
(/
(log1p (- u0))
(- (/ (/ cos2phi alphax) alphax) (/ sin2phi (* alphay alphay))))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
float tmp;
if (u0 <= 0.05249999836087227f) {
tmp = (u0 * (1.0f - (u0 * ((u0 * ((u0 * -0.25f) - 0.3333333333333333f)) - 0.5f)))) / (((sin2phi / alphay) / alphay) + (cos2phi / (alphax * alphax)));
} else {
tmp = log1pf(-u0) / (((cos2phi / alphax) / alphax) - (sin2phi / (alphay * alphay)));
}
return tmp;
}
function code(alphax, alphay, u0, cos2phi, sin2phi) tmp = Float32(0.0) if (u0 <= Float32(0.05249999836087227)) tmp = Float32(Float32(u0 * Float32(Float32(1.0) - Float32(u0 * Float32(Float32(u0 * Float32(Float32(u0 * Float32(-0.25)) - Float32(0.3333333333333333))) - Float32(0.5))))) / Float32(Float32(Float32(sin2phi / alphay) / alphay) + Float32(cos2phi / Float32(alphax * alphax)))); else tmp = Float32(log1p(Float32(-u0)) / Float32(Float32(Float32(cos2phi / alphax) / alphax) - Float32(sin2phi / Float32(alphay * alphay)))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;u0 \leq 0.05249999836087227:\\
\;\;\;\;\frac{u0 \cdot \left(1 - u0 \cdot \left(u0 \cdot \left(u0 \cdot -0.25 - 0.3333333333333333\right) - 0.5\right)\right)}{\frac{\frac{sin2phi}{alphay}}{alphay} + \frac{cos2phi}{alphax \cdot alphax}}\\
\mathbf{else}:\\
\;\;\;\;\frac{\mathsf{log1p}\left(-u0\right)}{\frac{\frac{cos2phi}{alphax}}{alphax} - \frac{sin2phi}{alphay \cdot alphay}}\\
\end{array}
\end{array}
if u0 < 0.0524999984Initial program 57.3%
distribute-frac-neg57.3%
distribute-neg-frac257.3%
neg-mul-157.3%
associate-/r*57.3%
remove-double-neg57.3%
distribute-frac-neg57.3%
distribute-neg-frac257.3%
metadata-eval57.3%
/-rgt-identity57.3%
sub-neg57.3%
log1p-define98.4%
Simplified98.4%
associate-/r*98.6%
div-inv98.5%
Applied egg-rr98.5%
Taylor expanded in u0 around 0 97.7%
un-div-inv97.8%
Applied egg-rr97.8%
if 0.0524999984 < u0 Initial program 97.7%
distribute-frac-neg97.7%
distribute-neg-frac297.7%
sub-neg97.7%
log1p-define99.1%
neg-sub099.1%
associate--r+99.1%
neg-sub099.1%
associate-/r*99.1%
distribute-neg-frac299.1%
Simplified99.1%
add-sqr-sqrt-0.0%
sqrt-unprod82.8%
sqr-neg82.8%
sqrt-prod82.8%
add-sqr-sqrt82.8%
div-inv82.8%
Applied egg-rr82.8%
associate-*r/82.8%
*-rgt-identity82.8%
Simplified82.8%
Final simplification95.5%
(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(log1p(Float32(-u0)) / Float32(Float32(Float32(cos2phi / alphax) / Float32(-alphax)) - Float32(Float32(sin2phi / alphay) / alphay))) end
\begin{array}{l}
\\
\frac{\mathsf{log1p}\left(-u0\right)}{\frac{\frac{cos2phi}{alphax}}{-alphax} - \frac{\frac{sin2phi}{alphay}}{alphay}}
\end{array}
Initial program 63.6%
distribute-frac-neg63.6%
distribute-neg-frac263.6%
sub-neg63.6%
log1p-define98.5%
neg-sub098.5%
associate--r+98.5%
neg-sub098.5%
associate-/r*98.5%
distribute-neg-frac298.5%
Simplified98.5%
associate-/r*98.7%
div-inv98.6%
Applied egg-rr98.6%
associate-*r/98.7%
*-rgt-identity98.7%
Simplified98.7%
(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(log1p(Float32(-u0)) / Float32(Float32(Float32(cos2phi / alphax) / Float32(-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 63.6%
distribute-frac-neg63.6%
distribute-neg-frac263.6%
sub-neg63.6%
log1p-define98.5%
neg-sub098.5%
associate--r+98.5%
neg-sub098.5%
associate-/r*98.5%
distribute-neg-frac298.5%
Simplified98.5%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (* u0 (- 1.0 (* u0 (- (* u0 (- (* u0 -0.25) 0.3333333333333333)) 0.5)))) (+ (/ (/ sin2phi alphay) alphay) (/ cos2phi (* alphax alphax)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (u0 * (1.0f - (u0 * ((u0 * ((u0 * -0.25f) - 0.3333333333333333f)) - 0.5f)))) / (((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 * (1.0e0 - (u0 * ((u0 * ((u0 * (-0.25e0)) - 0.3333333333333333e0)) - 0.5e0)))) / (((sin2phi / alphay) / alphay) + (cos2phi / (alphax * alphax)))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(u0 * Float32(Float32(1.0) - Float32(u0 * Float32(Float32(u0 * Float32(Float32(u0 * Float32(-0.25)) - Float32(0.3333333333333333))) - Float32(0.5))))) / Float32(Float32(Float32(sin2phi / alphay) / alphay) + Float32(cos2phi / Float32(alphax * alphax)))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = (u0 * (single(1.0) - (u0 * ((u0 * ((u0 * single(-0.25)) - single(0.3333333333333333))) - single(0.5))))) / (((sin2phi / alphay) / alphay) + (cos2phi / (alphax * alphax))); end
\begin{array}{l}
\\
\frac{u0 \cdot \left(1 - u0 \cdot \left(u0 \cdot \left(u0 \cdot -0.25 - 0.3333333333333333\right) - 0.5\right)\right)}{\frac{\frac{sin2phi}{alphay}}{alphay} + \frac{cos2phi}{alphax \cdot alphax}}
\end{array}
Initial program 63.6%
distribute-frac-neg63.6%
distribute-neg-frac263.6%
neg-mul-163.6%
associate-/r*63.6%
remove-double-neg63.6%
distribute-frac-neg63.6%
distribute-neg-frac263.6%
metadata-eval63.6%
/-rgt-identity63.6%
sub-neg63.6%
log1p-define98.5%
Simplified98.5%
associate-/r*98.7%
div-inv98.6%
Applied egg-rr98.6%
Taylor expanded in u0 around 0 91.2%
un-div-inv91.3%
Applied egg-rr91.3%
Final simplification91.3%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (* u0 (- 1.0 (* u0 (- (* u0 (- (* u0 -0.25) 0.3333333333333333)) 0.5)))) (+ (/ sin2phi (* alphay alphay)) (/ cos2phi (* alphax alphax)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (u0 * (1.0f - (u0 * ((u0 * ((u0 * -0.25f) - 0.3333333333333333f)) - 0.5f)))) / ((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 * (1.0e0 - (u0 * ((u0 * ((u0 * (-0.25e0)) - 0.3333333333333333e0)) - 0.5e0)))) / ((sin2phi / (alphay * alphay)) + (cos2phi / (alphax * alphax)))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(u0 * Float32(Float32(1.0) - Float32(u0 * Float32(Float32(u0 * Float32(Float32(u0 * Float32(-0.25)) - Float32(0.3333333333333333))) - Float32(0.5))))) / Float32(Float32(sin2phi / Float32(alphay * alphay)) + Float32(cos2phi / Float32(alphax * alphax)))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = (u0 * (single(1.0) - (u0 * ((u0 * ((u0 * single(-0.25)) - single(0.3333333333333333))) - single(0.5))))) / ((sin2phi / (alphay * alphay)) + (cos2phi / (alphax * alphax))); end
\begin{array}{l}
\\
\frac{u0 \cdot \left(1 - u0 \cdot \left(u0 \cdot \left(u0 \cdot -0.25 - 0.3333333333333333\right) - 0.5\right)\right)}{\frac{sin2phi}{alphay \cdot alphay} + \frac{cos2phi}{alphax \cdot alphax}}
\end{array}
Initial program 63.6%
Taylor expanded in u0 around 0 91.2%
Final simplification91.2%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (* u0 (- 1.0 (* u0 (- (* u0 -0.3333333333333333) 0.5)))) (+ (/ sin2phi (* alphay alphay)) (/ cos2phi (* alphax alphax)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (u0 * (1.0f - (u0 * ((u0 * -0.3333333333333333f) - 0.5f)))) / ((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 * (1.0e0 - (u0 * ((u0 * (-0.3333333333333333e0)) - 0.5e0)))) / ((sin2phi / (alphay * alphay)) + (cos2phi / (alphax * alphax)))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(u0 * Float32(Float32(1.0) - Float32(u0 * Float32(Float32(u0 * Float32(-0.3333333333333333)) - Float32(0.5))))) / Float32(Float32(sin2phi / Float32(alphay * alphay)) + Float32(cos2phi / Float32(alphax * alphax)))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = (u0 * (single(1.0) - (u0 * ((u0 * single(-0.3333333333333333)) - single(0.5))))) / ((sin2phi / (alphay * alphay)) + (cos2phi / (alphax * alphax))); end
\begin{array}{l}
\\
\frac{u0 \cdot \left(1 - u0 \cdot \left(u0 \cdot -0.3333333333333333 - 0.5\right)\right)}{\frac{sin2phi}{alphay \cdot alphay} + \frac{cos2phi}{alphax \cdot alphax}}
\end{array}
Initial program 63.6%
Taylor expanded in u0 around 0 89.2%
Final simplification89.2%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (* u0 (- 1.0 (* u0 -0.5))) (+ (/ sin2phi (* alphay alphay)) (/ cos2phi (* alphax alphax)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return (u0 * (1.0f - (u0 * -0.5f))) / ((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 * (1.0e0 - (u0 * (-0.5e0)))) / ((sin2phi / (alphay * alphay)) + (cos2phi / (alphax * alphax)))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(Float32(u0 * Float32(Float32(1.0) - Float32(u0 * Float32(-0.5)))) / Float32(Float32(sin2phi / Float32(alphay * alphay)) + Float32(cos2phi / Float32(alphax * alphax)))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = (u0 * (single(1.0) - (u0 * single(-0.5)))) / ((sin2phi / (alphay * alphay)) + (cos2phi / (alphax * alphax))); end
\begin{array}{l}
\\
\frac{u0 \cdot \left(1 - u0 \cdot -0.5\right)}{\frac{sin2phi}{alphay \cdot alphay} + \frac{cos2phi}{alphax \cdot alphax}}
\end{array}
Initial program 63.6%
Taylor expanded in u0 around 0 85.0%
Final simplification85.0%
(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(Float32(sin2phi / alphay) / alphay) + Float32(cos2phi / Float32(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{\frac{sin2phi}{alphay}}{alphay} + \frac{cos2phi}{alphax \cdot alphax}}
\end{array}
Initial program 63.6%
Taylor expanded in u0 around 0 72.2%
mul-1-neg72.2%
Simplified72.2%
associate-/r*98.7%
div-inv98.6%
Applied egg-rr72.2%
associate-*r/98.7%
*-rgt-identity98.7%
Simplified72.2%
Final simplification72.2%
(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(cos2phi / Float32(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{cos2phi}{alphax \cdot alphax}}
\end{array}
Initial program 63.6%
Taylor expanded in u0 around 0 72.2%
mul-1-neg72.2%
Simplified72.2%
Final simplification72.2%
herbie shell --seed 2024106
(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)))))