
(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 9 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(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 61.7%
distribute-frac-neg61.7%
distribute-neg-frac261.7%
sub-neg61.7%
log1p-define97.8%
neg-sub097.8%
associate--r+97.8%
neg-sub097.8%
associate-/r*97.8%
distribute-neg-frac297.8%
Simplified97.8%
associate-/r*98.0%
div-inv97.8%
Applied egg-rr97.8%
associate-*r/98.0%
*-rgt-identity98.0%
Simplified98.0%
(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 61.7%
distribute-frac-neg61.7%
distribute-neg-frac261.7%
sub-neg61.7%
log1p-define97.8%
neg-sub097.8%
associate--r+97.8%
neg-sub097.8%
associate-/r*97.8%
distribute-neg-frac297.8%
Simplified97.8%
(FPCore (alphax alphay u0 cos2phi sin2phi)
:precision binary32
(let* ((t_0 (/ sin2phi (* alphay alphay))))
(if (<= t_0 8000.0)
(/ u0 (+ t_0 (/ cos2phi (* alphax alphax))))
(/ (* u0 (+ (* u0 -0.5) -1.0)) (- (/ (/ cos2phi alphax) alphax) t_0)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
float t_0 = sin2phi / (alphay * alphay);
float tmp;
if (t_0 <= 8000.0f) {
tmp = u0 / (t_0 + (cos2phi / (alphax * alphax)));
} else {
tmp = (u0 * ((u0 * -0.5f) + -1.0f)) / (((cos2phi / alphax) / alphax) - t_0);
}
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 <= 8000.0e0) then
tmp = u0 / (t_0 + (cos2phi / (alphax * alphax)))
else
tmp = (u0 * ((u0 * (-0.5e0)) + (-1.0e0))) / (((cos2phi / alphax) / alphax) - t_0)
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(8000.0)) tmp = Float32(u0 / Float32(t_0 + Float32(cos2phi / Float32(alphax * alphax)))); else tmp = Float32(Float32(u0 * Float32(Float32(u0 * Float32(-0.5)) + Float32(-1.0))) / Float32(Float32(Float32(cos2phi / alphax) / alphax) - t_0)); 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(8000.0)) tmp = u0 / (t_0 + (cos2phi / (alphax * alphax))); else tmp = (u0 * ((u0 * single(-0.5)) + single(-1.0))) / (((cos2phi / alphax) / alphax) - t_0); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{sin2phi}{alphay \cdot alphay}\\
\mathbf{if}\;t\_0 \leq 8000:\\
\;\;\;\;\frac{u0}{t\_0 + \frac{cos2phi}{alphax \cdot alphax}}\\
\mathbf{else}:\\
\;\;\;\;\frac{u0 \cdot \left(u0 \cdot -0.5 + -1\right)}{\frac{\frac{cos2phi}{alphax}}{alphax} - t\_0}\\
\end{array}
\end{array}
if (/.f32 sin2phi (*.f32 alphay alphay)) < 8e3Initial program 55.2%
Taylor expanded in u0 around 0 75.2%
mul-1-neg75.2%
Simplified75.2%
if 8e3 < (/.f32 sin2phi (*.f32 alphay alphay)) Initial program 68.7%
distribute-frac-neg68.7%
distribute-neg-frac268.7%
sub-neg68.7%
log1p-define97.1%
neg-sub097.1%
associate--r+97.1%
neg-sub097.1%
associate-/r*97.1%
distribute-neg-frac297.1%
Simplified97.1%
add-sqr-sqrt-0.0%
sqrt-unprod96.6%
sqr-neg96.6%
sqrt-prod96.6%
add-sqr-sqrt96.6%
div-inv96.6%
Applied egg-rr96.6%
associate-*r/96.6%
*-rgt-identity96.6%
Simplified96.6%
Taylor expanded in u0 around 0 86.5%
Final simplification80.7%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ (* u0 (+ 1.0 (* u0 (+ 0.5 (* u0 (- 0.3333333333333333 (* u0 -0.25))))))) (+ (/ 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 + (u0 * (0.3333333333333333f - (u0 * -0.25f))))))) / ((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 + (u0 * (0.3333333333333333e0 - (u0 * (-0.25e0)))))))) / ((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(0.5) + Float32(u0 * Float32(Float32(0.3333333333333333) - Float32(u0 * Float32(-0.25)))))))) / 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) + (u0 * (single(0.3333333333333333) - (u0 * single(-0.25)))))))) / ((sin2phi / (alphay * alphay)) + (cos2phi / (alphax * alphax))); end
\begin{array}{l}
\\
\frac{u0 \cdot \left(1 + u0 \cdot \left(0.5 + u0 \cdot \left(0.3333333333333333 - u0 \cdot -0.25\right)\right)\right)}{\frac{sin2phi}{alphay \cdot alphay} + \frac{cos2phi}{alphax \cdot alphax}}
\end{array}
Initial program 61.7%
Taylor expanded in u0 around 0 92.6%
Final simplification92.6%
(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 61.7%
Taylor expanded in u0 around 0 90.7%
Final simplification90.7%
(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 61.7%
Taylor expanded in u0 around 0 86.9%
Final simplification86.9%
(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 61.7%
Taylor expanded in u0 around 0 75.6%
mul-1-neg75.6%
Simplified75.6%
associate-/r*98.0%
div-inv97.8%
Applied egg-rr75.5%
associate-*r/98.0%
*-rgt-identity98.0%
Simplified75.6%
Final simplification75.6%
(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 61.7%
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 (- (/ 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 61.7%
distribute-frac-neg61.7%
distribute-neg-frac261.7%
sub-neg61.7%
log1p-define97.8%
neg-sub097.8%
associate--r+97.8%
neg-sub097.8%
associate-/r*97.8%
distribute-neg-frac297.8%
Simplified97.8%
add-sqr-sqrt-0.0%
sqrt-unprod70.3%
sqr-neg70.3%
sqrt-prod70.3%
add-sqr-sqrt70.3%
div-inv70.3%
Applied egg-rr70.3%
associate-*r/70.3%
*-rgt-identity70.3%
Simplified70.3%
Taylor expanded in u0 around 0 55.4%
neg-mul-155.4%
Simplified55.4%
Final simplification55.4%
herbie shell --seed 2024103
(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)))))