
(FPCore (alpha u0) :precision binary32 (* (* (- alpha) alpha) (log (- 1.0 u0))))
float code(float alpha, float u0) {
return (-alpha * alpha) * logf((1.0f - u0));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (-alpha * alpha) * log((1.0e0 - u0))
end function
function code(alpha, u0) return Float32(Float32(Float32(-alpha) * alpha) * log(Float32(Float32(1.0) - u0))) end
function tmp = code(alpha, u0) tmp = (-alpha * alpha) * log((single(1.0) - u0)); end
\begin{array}{l}
\\
\left(\left(-\alpha\right) \cdot \alpha\right) \cdot \log \left(1 - u0\right)
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (alpha u0) :precision binary32 (* (* (- alpha) alpha) (log (- 1.0 u0))))
float code(float alpha, float u0) {
return (-alpha * alpha) * logf((1.0f - u0));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (-alpha * alpha) * log((1.0e0 - u0))
end function
function code(alpha, u0) return Float32(Float32(Float32(-alpha) * alpha) * log(Float32(Float32(1.0) - u0))) end
function tmp = code(alpha, u0) tmp = (-alpha * alpha) * log((single(1.0) - u0)); end
\begin{array}{l}
\\
\left(\left(-\alpha\right) \cdot \alpha\right) \cdot \log \left(1 - u0\right)
\end{array}
(FPCore (alpha u0)
:precision binary32
(if (<= (- 1.0 u0) 0.9998400211334229)
(*
(log (- 1.0 u0))
(* (* (* alpha alpha) (/ alpha (* (/ -1.0 (/ 1.0 alpha)) alpha))) alpha))
(* (* alpha alpha) u0)))
float code(float alpha, float u0) {
float tmp;
if ((1.0f - u0) <= 0.9998400211334229f) {
tmp = logf((1.0f - u0)) * (((alpha * alpha) * (alpha / ((-1.0f / (1.0f / alpha)) * alpha))) * alpha);
} else {
tmp = (alpha * alpha) * u0;
}
return tmp;
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
real(4) :: tmp
if ((1.0e0 - u0) <= 0.9998400211334229e0) then
tmp = log((1.0e0 - u0)) * (((alpha * alpha) * (alpha / (((-1.0e0) / (1.0e0 / alpha)) * alpha))) * alpha)
else
tmp = (alpha * alpha) * u0
end if
code = tmp
end function
function code(alpha, u0) tmp = Float32(0.0) if (Float32(Float32(1.0) - u0) <= Float32(0.9998400211334229)) tmp = Float32(log(Float32(Float32(1.0) - u0)) * Float32(Float32(Float32(alpha * alpha) * Float32(alpha / Float32(Float32(Float32(-1.0) / Float32(Float32(1.0) / alpha)) * alpha))) * alpha)); else tmp = Float32(Float32(alpha * alpha) * u0); end return tmp end
function tmp_2 = code(alpha, u0) tmp = single(0.0); if ((single(1.0) - u0) <= single(0.9998400211334229)) tmp = log((single(1.0) - u0)) * (((alpha * alpha) * (alpha / ((single(-1.0) / (single(1.0) / alpha)) * alpha))) * alpha); else tmp = (alpha * alpha) * u0; end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;1 - u0 \leq 0.9998400211334229:\\
\;\;\;\;\log \left(1 - u0\right) \cdot \left(\left(\left(\alpha \cdot \alpha\right) \cdot \frac{\alpha}{\frac{-1}{\frac{1}{\alpha}} \cdot \alpha}\right) \cdot \alpha\right)\\
\mathbf{else}:\\
\;\;\;\;\left(\alpha \cdot \alpha\right) \cdot u0\\
\end{array}
\end{array}
if (-.f32 #s(literal 1 binary32) u0) < 0.999840021Initial program 86.0%
lift-neg.f32N/A
neg-sub0N/A
flip3--N/A
frac-2negN/A
metadata-evalN/A
+-lft-identityN/A
mul0-lftN/A
+-rgt-identityN/A
distribute-lft-neg-outN/A
lift-neg.f32N/A
lift-*.f32N/A
div-invN/A
metadata-evalN/A
sub0-negN/A
remove-double-negN/A
lower-*.f32N/A
lower-pow.f32N/A
lower-/.f3285.9
Applied rewrites85.9%
lift-*.f32N/A
*-commutativeN/A
lift-pow.f32N/A
cube-multN/A
lift-*.f32N/A
associate-*r*N/A
lower-*.f32N/A
lift-/.f32N/A
associate-*l/N/A
*-lft-identityN/A
lower-/.f3286.0
Applied rewrites86.0%
remove-double-divN/A
lift-/.f32N/A
lift-/.f3286.1
lift-/.f32N/A
metadata-evalN/A
lift-neg.f32N/A
frac-2negN/A
lower-/.f3286.1
Applied rewrites86.1%
if 0.999840021 < (-.f32 #s(literal 1 binary32) u0) Initial program 33.9%
Taylor expanded in u0 around 0
*-commutativeN/A
lower-*.f32N/A
unpow2N/A
lower-*.f3291.9
Applied rewrites91.9%
Final simplification90.0%
(FPCore (alpha u0) :precision binary32 (if (<= (- 1.0 u0) 0.9998400211334229) (* (/ 1.0 (/ -1.0 (* alpha alpha))) (log (- 1.0 u0))) (* (* alpha alpha) u0)))
float code(float alpha, float u0) {
float tmp;
if ((1.0f - u0) <= 0.9998400211334229f) {
tmp = (1.0f / (-1.0f / (alpha * alpha))) * logf((1.0f - u0));
} else {
tmp = (alpha * alpha) * u0;
}
return tmp;
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
real(4) :: tmp
if ((1.0e0 - u0) <= 0.9998400211334229e0) then
tmp = (1.0e0 / ((-1.0e0) / (alpha * alpha))) * log((1.0e0 - u0))
else
tmp = (alpha * alpha) * u0
end if
code = tmp
end function
function code(alpha, u0) tmp = Float32(0.0) if (Float32(Float32(1.0) - u0) <= Float32(0.9998400211334229)) tmp = Float32(Float32(Float32(1.0) / Float32(Float32(-1.0) / Float32(alpha * alpha))) * log(Float32(Float32(1.0) - u0))); else tmp = Float32(Float32(alpha * alpha) * u0); end return tmp end
function tmp_2 = code(alpha, u0) tmp = single(0.0); if ((single(1.0) - u0) <= single(0.9998400211334229)) tmp = (single(1.0) / (single(-1.0) / (alpha * alpha))) * log((single(1.0) - u0)); else tmp = (alpha * alpha) * u0; end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;1 - u0 \leq 0.9998400211334229:\\
\;\;\;\;\frac{1}{\frac{-1}{\alpha \cdot \alpha}} \cdot \log \left(1 - u0\right)\\
\mathbf{else}:\\
\;\;\;\;\left(\alpha \cdot \alpha\right) \cdot u0\\
\end{array}
\end{array}
if (-.f32 #s(literal 1 binary32) u0) < 0.999840021Initial program 86.0%
lift-*.f32N/A
lift-neg.f32N/A
distribute-lft-neg-outN/A
neg-sub0N/A
flip3--N/A
div-invN/A
metadata-evalN/A
+-lft-identityN/A
mul0-lftN/A
metadata-evalN/A
metadata-evalN/A
mul0-rgtN/A
mul0-lftN/A
mul0-lftN/A
mul0-lftN/A
lower-*.f32N/A
Applied rewrites86.0%
lift-*.f32N/A
lift-neg.f32N/A
distribute-lft-neg-outN/A
lift-pow.f32N/A
lift-/.f32N/A
lift-pow.f32N/A
pow-flipN/A
pow-prod-upN/A
metadata-evalN/A
metadata-evalN/A
pow2N/A
distribute-lft-neg-outN/A
lift-neg.f32N/A
lift-*.f3286.0
/-rgt-identityN/A
clear-numN/A
lift-/.f32N/A
lower-/.f3286.0
lift-/.f32N/A
frac-2negN/A
metadata-evalN/A
lift-*.f32N/A
lift-neg.f32N/A
distribute-lft-neg-outN/A
lift-*.f32N/A
remove-double-negN/A
lower-/.f3286.0
Applied rewrites86.0%
if 0.999840021 < (-.f32 #s(literal 1 binary32) u0) Initial program 33.9%
Taylor expanded in u0 around 0
*-commutativeN/A
lower-*.f32N/A
unpow2N/A
lower-*.f3291.9
Applied rewrites91.9%
Final simplification90.0%
(FPCore (alpha u0) :precision binary32 (if (<= (- 1.0 u0) 0.9998400211334229) (* (* (/ -1.0 alpha) (* (* alpha alpha) alpha)) (log (- 1.0 u0))) (* (* alpha alpha) u0)))
float code(float alpha, float u0) {
float tmp;
if ((1.0f - u0) <= 0.9998400211334229f) {
tmp = ((-1.0f / alpha) * ((alpha * alpha) * alpha)) * logf((1.0f - u0));
} else {
tmp = (alpha * alpha) * u0;
}
return tmp;
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
real(4) :: tmp
if ((1.0e0 - u0) <= 0.9998400211334229e0) then
tmp = (((-1.0e0) / alpha) * ((alpha * alpha) * alpha)) * log((1.0e0 - u0))
else
tmp = (alpha * alpha) * u0
end if
code = tmp
end function
function code(alpha, u0) tmp = Float32(0.0) if (Float32(Float32(1.0) - u0) <= Float32(0.9998400211334229)) tmp = Float32(Float32(Float32(Float32(-1.0) / alpha) * Float32(Float32(alpha * alpha) * alpha)) * log(Float32(Float32(1.0) - u0))); else tmp = Float32(Float32(alpha * alpha) * u0); end return tmp end
function tmp_2 = code(alpha, u0) tmp = single(0.0); if ((single(1.0) - u0) <= single(0.9998400211334229)) tmp = ((single(-1.0) / alpha) * ((alpha * alpha) * alpha)) * log((single(1.0) - u0)); else tmp = (alpha * alpha) * u0; end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;1 - u0 \leq 0.9998400211334229:\\
\;\;\;\;\left(\frac{-1}{\alpha} \cdot \left(\left(\alpha \cdot \alpha\right) \cdot \alpha\right)\right) \cdot \log \left(1 - u0\right)\\
\mathbf{else}:\\
\;\;\;\;\left(\alpha \cdot \alpha\right) \cdot u0\\
\end{array}
\end{array}
if (-.f32 #s(literal 1 binary32) u0) < 0.999840021Initial program 86.0%
lift-*.f32N/A
lift-neg.f32N/A
neg-sub0N/A
flip--N/A
metadata-evalN/A
neg-sub0N/A
distribute-lft-neg-outN/A
lift-neg.f32N/A
lift-*.f32N/A
+-lft-identityN/A
associate-*l/N/A
div-invN/A
+-lft-identityN/A
lower-*.f32N/A
lower-*.f32N/A
+-lft-identityN/A
lower-/.f3286.0
Applied rewrites86.0%
if 0.999840021 < (-.f32 #s(literal 1 binary32) u0) Initial program 33.9%
Taylor expanded in u0 around 0
*-commutativeN/A
lower-*.f32N/A
unpow2N/A
lower-*.f3291.9
Applied rewrites91.9%
Final simplification90.0%
(FPCore (alpha u0) :precision binary32 (if (<= (- 1.0 u0) 0.9998400211334229) (* (* (- alpha) alpha) (log (- 1.0 u0))) (* (* alpha alpha) u0)))
float code(float alpha, float u0) {
float tmp;
if ((1.0f - u0) <= 0.9998400211334229f) {
tmp = (-alpha * alpha) * logf((1.0f - u0));
} else {
tmp = (alpha * alpha) * u0;
}
return tmp;
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
real(4) :: tmp
if ((1.0e0 - u0) <= 0.9998400211334229e0) then
tmp = (-alpha * alpha) * log((1.0e0 - u0))
else
tmp = (alpha * alpha) * u0
end if
code = tmp
end function
function code(alpha, u0) tmp = Float32(0.0) if (Float32(Float32(1.0) - u0) <= Float32(0.9998400211334229)) tmp = Float32(Float32(Float32(-alpha) * alpha) * log(Float32(Float32(1.0) - u0))); else tmp = Float32(Float32(alpha * alpha) * u0); end return tmp end
function tmp_2 = code(alpha, u0) tmp = single(0.0); if ((single(1.0) - u0) <= single(0.9998400211334229)) tmp = (-alpha * alpha) * log((single(1.0) - u0)); else tmp = (alpha * alpha) * u0; end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;1 - u0 \leq 0.9998400211334229:\\
\;\;\;\;\left(\left(-\alpha\right) \cdot \alpha\right) \cdot \log \left(1 - u0\right)\\
\mathbf{else}:\\
\;\;\;\;\left(\alpha \cdot \alpha\right) \cdot u0\\
\end{array}
\end{array}
if (-.f32 #s(literal 1 binary32) u0) < 0.999840021Initial program 86.0%
if 0.999840021 < (-.f32 #s(literal 1 binary32) u0) Initial program 33.9%
Taylor expanded in u0 around 0
*-commutativeN/A
lower-*.f32N/A
unpow2N/A
lower-*.f3291.9
Applied rewrites91.9%
Final simplification90.0%
(FPCore (alpha u0) :precision binary32 (if (<= (- 1.0 u0) 0.9998400211334229) (* (* (- alpha) (log (- 1.0 u0))) alpha) (* (* alpha alpha) u0)))
float code(float alpha, float u0) {
float tmp;
if ((1.0f - u0) <= 0.9998400211334229f) {
tmp = (-alpha * logf((1.0f - u0))) * alpha;
} else {
tmp = (alpha * alpha) * u0;
}
return tmp;
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
real(4) :: tmp
if ((1.0e0 - u0) <= 0.9998400211334229e0) then
tmp = (-alpha * log((1.0e0 - u0))) * alpha
else
tmp = (alpha * alpha) * u0
end if
code = tmp
end function
function code(alpha, u0) tmp = Float32(0.0) if (Float32(Float32(1.0) - u0) <= Float32(0.9998400211334229)) tmp = Float32(Float32(Float32(-alpha) * log(Float32(Float32(1.0) - u0))) * alpha); else tmp = Float32(Float32(alpha * alpha) * u0); end return tmp end
function tmp_2 = code(alpha, u0) tmp = single(0.0); if ((single(1.0) - u0) <= single(0.9998400211334229)) tmp = (-alpha * log((single(1.0) - u0))) * alpha; else tmp = (alpha * alpha) * u0; end tmp_2 = tmp; end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;1 - u0 \leq 0.9998400211334229:\\
\;\;\;\;\left(\left(-\alpha\right) \cdot \log \left(1 - u0\right)\right) \cdot \alpha\\
\mathbf{else}:\\
\;\;\;\;\left(\alpha \cdot \alpha\right) \cdot u0\\
\end{array}
\end{array}
if (-.f32 #s(literal 1 binary32) u0) < 0.999840021Initial program 86.0%
Taylor expanded in alpha around 0
mul-1-negN/A
unpow2N/A
associate-*l*N/A
distribute-rgt-neg-inN/A
*-commutativeN/A
lower-*.f32N/A
distribute-lft-neg-inN/A
mul-1-negN/A
lower-*.f32N/A
mul-1-negN/A
lower-neg.f32N/A
sub-negN/A
lower-log1p.f32N/A
lower-neg.f3251.0
Applied rewrites51.0%
Applied rewrites85.9%
if 0.999840021 < (-.f32 #s(literal 1 binary32) u0) Initial program 33.9%
Taylor expanded in u0 around 0
*-commutativeN/A
lower-*.f32N/A
unpow2N/A
lower-*.f3291.9
Applied rewrites91.9%
Final simplification90.0%
(FPCore (alpha u0) :precision binary32 (* (* alpha alpha) u0))
float code(float alpha, float u0) {
return (alpha * alpha) * u0;
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (alpha * alpha) * u0
end function
function code(alpha, u0) return Float32(Float32(alpha * alpha) * u0) end
function tmp = code(alpha, u0) tmp = (alpha * alpha) * u0; end
\begin{array}{l}
\\
\left(\alpha \cdot \alpha\right) \cdot u0
\end{array}
Initial program 50.6%
Taylor expanded in u0 around 0
*-commutativeN/A
lower-*.f32N/A
unpow2N/A
lower-*.f3278.8
Applied rewrites78.8%
Final simplification78.8%
herbie shell --seed 2024266
(FPCore (alpha u0)
:name "Beckmann Distribution sample, tan2theta, alphax == alphay"
:precision binary32
:pre (and (and (<= 0.0001 alpha) (<= alpha 1.0)) (and (<= 2.328306437e-10 u0) (<= u0 1.0)))
(* (* (- alpha) alpha) (log (- 1.0 u0))))