
(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(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 58.4%
neg-sub058.4%
div-sub58.4%
--rgt-identity58.4%
div-sub58.4%
--rgt-identity58.4%
neg-sub058.4%
sub-neg58.4%
log1p-def98.9%
Simplified98.9%
Final simplification98.9%
(FPCore (alphax alphay u0 cos2phi sin2phi)
:precision binary32
(if (<= sin2phi 1.0000000116860974e-7)
(/
u0
(+ (/ sin2phi (* alphay alphay)) (* cos2phi (/ 1.0 (* alphax alphax)))))
(* (- (log1p (- u0))) (/ alphay (/ sin2phi alphay)))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
float tmp;
if (sin2phi <= 1.0000000116860974e-7f) {
tmp = u0 / ((sin2phi / (alphay * alphay)) + (cos2phi * (1.0f / (alphax * alphax))));
} else {
tmp = -log1pf(-u0) * (alphay / (sin2phi / alphay));
}
return tmp;
}
function code(alphax, alphay, u0, cos2phi, sin2phi) tmp = Float32(0.0) if (sin2phi <= Float32(1.0000000116860974e-7)) tmp = Float32(u0 / Float32(Float32(sin2phi / Float32(alphay * alphay)) + Float32(cos2phi * Float32(Float32(1.0) / Float32(alphax * alphax))))); else tmp = Float32(Float32(-log1p(Float32(-u0))) * Float32(alphay / Float32(sin2phi / alphay))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;sin2phi \leq 1.0000000116860974 \cdot 10^{-7}:\\
\;\;\;\;\frac{u0}{\frac{sin2phi}{alphay \cdot alphay} + cos2phi \cdot \frac{1}{alphax \cdot alphax}}\\
\mathbf{else}:\\
\;\;\;\;\left(-\mathsf{log1p}\left(-u0\right)\right) \cdot \frac{alphay}{\frac{sin2phi}{alphay}}\\
\end{array}
\end{array}
if sin2phi < 1.00000001e-7Initial program 55.5%
associate-/r*55.5%
Simplified55.5%
Taylor expanded in u0 around 0 75.3%
unpow275.3%
unpow275.3%
Simplified75.3%
div-inv75.4%
Applied egg-rr75.4%
if 1.00000001e-7 < sin2phi Initial program 60.6%
neg-sub060.6%
div-sub60.6%
--rgt-identity60.6%
div-sub60.6%
--rgt-identity60.6%
sub-neg60.6%
+-commutative60.6%
neg-sub060.6%
associate-+l-60.6%
sub0-neg60.6%
neg-mul-160.6%
log-prod-0.0%
associate--r+-0.0%
Simplified99.0%
div-inv99.0%
Applied egg-rr99.0%
div-inv98.7%
div-inv98.7%
+-commutative98.7%
associate-/r*98.7%
Applied egg-rr98.7%
Taylor expanded in sin2phi around inf 96.4%
unpow296.4%
associate-/l*96.2%
Simplified96.2%
Final simplification87.3%
(FPCore (alphax alphay u0 cos2phi sin2phi)
:precision binary32
(if (<= sin2phi 1.99999996490334e-13)
(/
u0
(+ (/ sin2phi (* alphay alphay)) (* cos2phi (/ 1.0 (* alphax alphax)))))
(* (log1p (- u0)) (/ (- (* alphay alphay)) sin2phi))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
float tmp;
if (sin2phi <= 1.99999996490334e-13f) {
tmp = u0 / ((sin2phi / (alphay * alphay)) + (cos2phi * (1.0f / (alphax * alphax))));
} else {
tmp = log1pf(-u0) * (-(alphay * alphay) / sin2phi);
}
return tmp;
}
function code(alphax, alphay, u0, cos2phi, sin2phi) tmp = Float32(0.0) if (sin2phi <= Float32(1.99999996490334e-13)) tmp = Float32(u0 / Float32(Float32(sin2phi / Float32(alphay * alphay)) + Float32(cos2phi * Float32(Float32(1.0) / Float32(alphax * alphax))))); else tmp = Float32(log1p(Float32(-u0)) * Float32(Float32(-Float32(alphay * alphay)) / sin2phi)); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;sin2phi \leq 1.99999996490334 \cdot 10^{-13}:\\
\;\;\;\;\frac{u0}{\frac{sin2phi}{alphay \cdot alphay} + cos2phi \cdot \frac{1}{alphax \cdot alphax}}\\
\mathbf{else}:\\
\;\;\;\;\mathsf{log1p}\left(-u0\right) \cdot \frac{-alphay \cdot alphay}{sin2phi}\\
\end{array}
\end{array}
if sin2phi < 1.99999996e-13Initial program 53.5%
associate-/r*53.5%
Simplified53.5%
Taylor expanded in u0 around 0 76.8%
unpow276.8%
unpow276.8%
Simplified76.8%
div-inv76.9%
Applied egg-rr76.9%
if 1.99999996e-13 < sin2phi Initial program 61.0%
neg-sub061.0%
div-sub61.0%
--rgt-identity61.0%
div-sub61.0%
--rgt-identity61.0%
sub-neg61.0%
+-commutative61.0%
neg-sub061.0%
associate-+l-61.0%
sub0-neg61.0%
neg-mul-161.0%
log-prod-0.0%
associate--r+-0.0%
Simplified99.0%
div-inv99.0%
Applied egg-rr99.0%
div-inv98.7%
div-inv98.7%
+-commutative98.7%
associate-/r*98.7%
Applied egg-rr98.7%
Taylor expanded in sin2phi around inf 93.0%
unpow293.0%
Simplified93.0%
Final simplification87.4%
(FPCore (alphax alphay u0 cos2phi sin2phi)
:precision binary32
(let* ((t_0 (/ sin2phi (* alphay alphay))))
(if (<= sin2phi 1.0000000116860974e-7)
(/ u0 (+ t_0 (* cos2phi (/ 1.0 (* alphax alphax)))))
(/ (- (log1p (- u0))) t_0))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
float t_0 = sin2phi / (alphay * alphay);
float tmp;
if (sin2phi <= 1.0000000116860974e-7f) {
tmp = u0 / (t_0 + (cos2phi * (1.0f / (alphax * alphax))));
} else {
tmp = -log1pf(-u0) / t_0;
}
return tmp;
}
function code(alphax, alphay, u0, cos2phi, sin2phi) t_0 = Float32(sin2phi / Float32(alphay * alphay)) tmp = Float32(0.0) if (sin2phi <= Float32(1.0000000116860974e-7)) tmp = Float32(u0 / Float32(t_0 + Float32(cos2phi * Float32(Float32(1.0) / Float32(alphax * alphax))))); else tmp = Float32(Float32(-log1p(Float32(-u0))) / t_0); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{sin2phi}{alphay \cdot alphay}\\
\mathbf{if}\;sin2phi \leq 1.0000000116860974 \cdot 10^{-7}:\\
\;\;\;\;\frac{u0}{t_0 + cos2phi \cdot \frac{1}{alphax \cdot alphax}}\\
\mathbf{else}:\\
\;\;\;\;\frac{-\mathsf{log1p}\left(-u0\right)}{t_0}\\
\end{array}
\end{array}
if sin2phi < 1.00000001e-7Initial program 55.5%
associate-/r*55.5%
Simplified55.5%
Taylor expanded in u0 around 0 75.3%
unpow275.3%
unpow275.3%
Simplified75.3%
div-inv75.4%
Applied egg-rr75.4%
if 1.00000001e-7 < sin2phi Initial program 60.6%
neg-sub060.6%
div-sub60.6%
--rgt-identity60.6%
div-sub60.6%
--rgt-identity60.6%
sub-neg60.6%
+-commutative60.6%
neg-sub060.6%
associate-+l-60.6%
sub0-neg60.6%
neg-mul-160.6%
log-prod-0.0%
associate--r+-0.0%
Simplified99.0%
div-inv99.0%
Applied egg-rr99.0%
Taylor expanded in cos2phi around 0 96.4%
unpow296.4%
Simplified96.4%
Final simplification87.5%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (/ u0 (+ (/ sin2phi (* alphay alphay)) (* cos2phi (/ 1.0 (* alphax alphax))))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
return u0 / ((sin2phi / (alphay * alphay)) + (cos2phi * (1.0f / (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 * (1.0e0 / (alphax * alphax))))
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) return Float32(u0 / Float32(Float32(sin2phi / Float32(alphay * alphay)) + Float32(cos2phi * Float32(Float32(1.0) / Float32(alphax * alphax))))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = u0 / ((sin2phi / (alphay * alphay)) + (cos2phi * (single(1.0) / (alphax * alphax)))); end
\begin{array}{l}
\\
\frac{u0}{\frac{sin2phi}{alphay \cdot alphay} + cos2phi \cdot \frac{1}{alphax \cdot alphax}}
\end{array}
Initial program 58.4%
associate-/r*58.4%
Simplified58.4%
Taylor expanded in u0 around 0 77.4%
unpow277.4%
unpow277.4%
Simplified77.4%
div-inv77.4%
Applied egg-rr77.4%
Final simplification77.4%
(FPCore (alphax alphay u0 cos2phi sin2phi) :precision binary32 (if (<= (/ sin2phi (* alphay alphay)) 1.5000000583807998e-17) (* u0 (/ (* alphax alphax) cos2phi)) (* (* alphay alphay) (/ u0 sin2phi))))
float code(float alphax, float alphay, float u0, float cos2phi, float sin2phi) {
float tmp;
if ((sin2phi / (alphay * alphay)) <= 1.5000000583807998e-17f) {
tmp = u0 * ((alphax * alphax) / cos2phi);
} else {
tmp = (alphay * alphay) * (u0 / sin2phi);
}
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) :: tmp
if ((sin2phi / (alphay * alphay)) <= 1.5000000583807998e-17) then
tmp = u0 * ((alphax * alphax) / cos2phi)
else
tmp = (alphay * alphay) * (u0 / sin2phi)
end if
code = tmp
end function
function code(alphax, alphay, u0, cos2phi, sin2phi) tmp = Float32(0.0) if (Float32(sin2phi / Float32(alphay * alphay)) <= Float32(1.5000000583807998e-17)) tmp = Float32(u0 * Float32(Float32(alphax * alphax) / cos2phi)); else tmp = Float32(Float32(alphay * alphay) * Float32(u0 / sin2phi)); end return tmp end
function tmp_2 = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = single(0.0); if ((sin2phi / (alphay * alphay)) <= single(1.5000000583807998e-17)) tmp = u0 * ((alphax * alphax) / cos2phi); else tmp = (alphay * alphay) * (u0 / sin2phi); end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\frac{sin2phi}{alphay \cdot alphay} \leq 1.5000000583807998 \cdot 10^{-17}:\\
\;\;\;\;u0 \cdot \frac{alphax \cdot alphax}{cos2phi}\\
\mathbf{else}:\\
\;\;\;\;\left(alphay \cdot alphay\right) \cdot \frac{u0}{sin2phi}\\
\end{array}
\end{array}
if (/.f32 sin2phi (*.f32 alphay alphay)) < 1.5000001e-17Initial program 56.4%
associate-/r*56.4%
Simplified56.4%
Taylor expanded in u0 around 0 75.0%
unpow275.0%
unpow275.0%
Simplified75.0%
Taylor expanded in cos2phi around inf 59.2%
unpow259.2%
associate-/l*59.6%
Simplified59.6%
Taylor expanded in u0 around 0 59.2%
associate-*r/59.6%
unpow259.6%
Simplified59.6%
if 1.5000001e-17 < (/.f32 sin2phi (*.f32 alphay alphay)) Initial program 59.0%
neg-sub059.0%
div-sub59.0%
--rgt-identity59.0%
div-sub59.0%
--rgt-identity59.0%
neg-sub059.0%
sub-neg59.0%
log1p-def99.0%
Simplified99.0%
clear-num98.7%
associate-/r*98.7%
frac-add98.5%
associate-/l*98.5%
*-commutative98.5%
*-un-lft-identity98.5%
associate-/l*98.4%
Applied egg-rr98.4%
Taylor expanded in u0 around 0 78.2%
times-frac78.1%
+-commutative78.1%
unpow278.1%
times-frac78.1%
unpow278.1%
*-commutative78.1%
Simplified78.1%
Taylor expanded in alphax around inf 70.8%
associate-/l*70.8%
associate-/r/70.9%
unpow270.9%
Simplified70.9%
Final simplification68.2%
(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 58.4%
associate-/r*58.4%
Simplified58.4%
Taylor expanded in u0 around 0 77.4%
unpow277.4%
unpow277.4%
Simplified77.4%
Final simplification77.4%
(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(u0 * Float32(alphax * Float32(alphax / cos2phi))) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = u0 * (alphax * (alphax / cos2phi)); end
\begin{array}{l}
\\
u0 \cdot \left(alphax \cdot \frac{alphax}{cos2phi}\right)
\end{array}
Initial program 58.4%
associate-/r*58.4%
Simplified58.4%
Taylor expanded in u0 around 0 77.4%
unpow277.4%
unpow277.4%
Simplified77.4%
Taylor expanded in cos2phi around inf 24.0%
unpow224.0%
associate-/l*24.1%
Simplified24.1%
div-inv24.1%
associate-/r*24.0%
clear-num24.0%
associate-/r/24.1%
Applied egg-rr24.1%
Final simplification24.1%
(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(u0 * Float32(Float32(alphax * alphax) / cos2phi)) end
function tmp = code(alphax, alphay, u0, cos2phi, sin2phi) tmp = u0 * ((alphax * alphax) / cos2phi); end
\begin{array}{l}
\\
u0 \cdot \frac{alphax \cdot alphax}{cos2phi}
\end{array}
Initial program 58.4%
associate-/r*58.4%
Simplified58.4%
Taylor expanded in u0 around 0 77.4%
unpow277.4%
unpow277.4%
Simplified77.4%
Taylor expanded in cos2phi around inf 24.0%
unpow224.0%
associate-/l*24.1%
Simplified24.1%
Taylor expanded in u0 around 0 24.0%
associate-*r/24.1%
unpow224.1%
Simplified24.1%
Final simplification24.1%
herbie shell --seed 2023224
(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)))))