
(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 7 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 (* (* alpha (- alpha)) (log1p (- u0))))
float code(float alpha, float u0) {
return (alpha * -alpha) * log1pf(-u0);
}
function code(alpha, u0) return Float32(Float32(alpha * Float32(-alpha)) * log1p(Float32(-u0))) end
\begin{array}{l}
\\
\left(\alpha \cdot \left(-\alpha\right)\right) \cdot \mathsf{log1p}\left(-u0\right)
\end{array}
Initial program 52.9%
*-commutative52.9%
sub-neg52.9%
log1p-def99.2%
Simplified99.2%
Final simplification99.2%
(FPCore (alpha u0) :precision binary32 (* (- alpha) (* alpha (log1p (- u0)))))
float code(float alpha, float u0) {
return -alpha * (alpha * log1pf(-u0));
}
function code(alpha, u0) return Float32(Float32(-alpha) * Float32(alpha * log1p(Float32(-u0)))) end
\begin{array}{l}
\\
\left(-\alpha\right) \cdot \left(\alpha \cdot \mathsf{log1p}\left(-u0\right)\right)
\end{array}
Initial program 52.9%
associate-*l*52.9%
sub-neg52.9%
log1p-def99.0%
Simplified99.0%
Final simplification99.0%
(FPCore (alpha u0) :precision binary32 (let* ((t_0 (* (* u0 0.3333333333333333) (* u0 u0))) (t_1 (* (* u0 u0) 0.5))) (* (* alpha alpha) (+ u0 (/ (- (* t_0 t_0) (* t_1 t_1)) (- t_0 t_1))))))
float code(float alpha, float u0) {
float t_0 = (u0 * 0.3333333333333333f) * (u0 * u0);
float t_1 = (u0 * u0) * 0.5f;
return (alpha * alpha) * (u0 + (((t_0 * t_0) - (t_1 * t_1)) / (t_0 - t_1)));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
real(4) :: t_0
real(4) :: t_1
t_0 = (u0 * 0.3333333333333333e0) * (u0 * u0)
t_1 = (u0 * u0) * 0.5e0
code = (alpha * alpha) * (u0 + (((t_0 * t_0) - (t_1 * t_1)) / (t_0 - t_1)))
end function
function code(alpha, u0) t_0 = Float32(Float32(u0 * Float32(0.3333333333333333)) * Float32(u0 * u0)) t_1 = Float32(Float32(u0 * u0) * Float32(0.5)) return Float32(Float32(alpha * alpha) * Float32(u0 + Float32(Float32(Float32(t_0 * t_0) - Float32(t_1 * t_1)) / Float32(t_0 - t_1)))) end
function tmp = code(alpha, u0) t_0 = (u0 * single(0.3333333333333333)) * (u0 * u0); t_1 = (u0 * u0) * single(0.5); tmp = (alpha * alpha) * (u0 + (((t_0 * t_0) - (t_1 * t_1)) / (t_0 - t_1))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(u0 \cdot 0.3333333333333333\right) \cdot \left(u0 \cdot u0\right)\\
t_1 := \left(u0 \cdot u0\right) \cdot 0.5\\
\left(\alpha \cdot \alpha\right) \cdot \left(u0 + \frac{t_0 \cdot t_0 - t_1 \cdot t_1}{t_0 - t_1}\right)
\end{array}
\end{array}
Initial program 52.9%
associate-*l*52.9%
sub-neg52.9%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 92.4%
*-commutative92.4%
+-commutative92.4%
associate-*r*92.4%
associate-*r*92.4%
distribute-rgt-out92.4%
distribute-lft-out92.5%
unpow292.5%
+-commutative92.5%
cube-mult92.5%
unpow292.5%
associate-*r*92.5%
distribute-rgt-out92.5%
unpow292.5%
*-commutative92.5%
Simplified92.5%
distribute-rgt-in92.5%
flip-+92.5%
Applied egg-rr92.5%
Final simplification92.5%
(FPCore (alpha u0)
:precision binary32
(*
(* alpha alpha)
(+
u0
(*
(* u0 u0)
(/
(- 0.25 (* (* u0 u0) 0.1111111111111111))
(- 0.5 (* u0 0.3333333333333333)))))))
float code(float alpha, float u0) {
return (alpha * alpha) * (u0 + ((u0 * u0) * ((0.25f - ((u0 * u0) * 0.1111111111111111f)) / (0.5f - (u0 * 0.3333333333333333f)))));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (alpha * alpha) * (u0 + ((u0 * u0) * ((0.25e0 - ((u0 * u0) * 0.1111111111111111e0)) / (0.5e0 - (u0 * 0.3333333333333333e0)))))
end function
function code(alpha, u0) return Float32(Float32(alpha * alpha) * Float32(u0 + Float32(Float32(u0 * u0) * Float32(Float32(Float32(0.25) - Float32(Float32(u0 * u0) * Float32(0.1111111111111111))) / Float32(Float32(0.5) - Float32(u0 * Float32(0.3333333333333333))))))) end
function tmp = code(alpha, u0) tmp = (alpha * alpha) * (u0 + ((u0 * u0) * ((single(0.25) - ((u0 * u0) * single(0.1111111111111111))) / (single(0.5) - (u0 * single(0.3333333333333333)))))); end
\begin{array}{l}
\\
\left(\alpha \cdot \alpha\right) \cdot \left(u0 + \left(u0 \cdot u0\right) \cdot \frac{0.25 - \left(u0 \cdot u0\right) \cdot 0.1111111111111111}{0.5 - u0 \cdot 0.3333333333333333}\right)
\end{array}
Initial program 52.9%
associate-*l*52.9%
sub-neg52.9%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 92.4%
*-commutative92.4%
+-commutative92.4%
associate-*r*92.4%
associate-*r*92.4%
distribute-rgt-out92.4%
distribute-lft-out92.5%
unpow292.5%
+-commutative92.5%
cube-mult92.5%
unpow292.5%
associate-*r*92.5%
distribute-rgt-out92.5%
unpow292.5%
*-commutative92.5%
Simplified92.5%
+-commutative92.5%
flip-+92.5%
metadata-eval92.5%
swap-sqr92.5%
metadata-eval92.5%
Applied egg-rr92.5%
Final simplification92.5%
(FPCore (alpha u0) :precision binary32 (* (* alpha alpha) (+ u0 (* (* u0 u0) (+ (* u0 0.3333333333333333) 0.5)))))
float code(float alpha, float u0) {
return (alpha * alpha) * (u0 + ((u0 * u0) * ((u0 * 0.3333333333333333f) + 0.5f)));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (alpha * alpha) * (u0 + ((u0 * u0) * ((u0 * 0.3333333333333333e0) + 0.5e0)))
end function
function code(alpha, u0) return Float32(Float32(alpha * alpha) * Float32(u0 + Float32(Float32(u0 * u0) * Float32(Float32(u0 * Float32(0.3333333333333333)) + Float32(0.5))))) end
function tmp = code(alpha, u0) tmp = (alpha * alpha) * (u0 + ((u0 * u0) * ((u0 * single(0.3333333333333333)) + single(0.5)))); end
\begin{array}{l}
\\
\left(\alpha \cdot \alpha\right) \cdot \left(u0 + \left(u0 \cdot u0\right) \cdot \left(u0 \cdot 0.3333333333333333 + 0.5\right)\right)
\end{array}
Initial program 52.9%
associate-*l*52.9%
sub-neg52.9%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 92.4%
*-commutative92.4%
+-commutative92.4%
associate-*r*92.4%
associate-*r*92.4%
distribute-rgt-out92.4%
distribute-lft-out92.5%
unpow292.5%
+-commutative92.5%
cube-mult92.5%
unpow292.5%
associate-*r*92.5%
distribute-rgt-out92.5%
unpow292.5%
*-commutative92.5%
Simplified92.5%
Final simplification92.5%
(FPCore (alpha u0) :precision binary32 (* (* alpha alpha) (+ u0 (* (* u0 u0) 0.5))))
float code(float alpha, float u0) {
return (alpha * alpha) * (u0 + ((u0 * u0) * 0.5f));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = (alpha * alpha) * (u0 + ((u0 * u0) * 0.5e0))
end function
function code(alpha, u0) return Float32(Float32(alpha * alpha) * Float32(u0 + Float32(Float32(u0 * u0) * Float32(0.5)))) end
function tmp = code(alpha, u0) tmp = (alpha * alpha) * (u0 + ((u0 * u0) * single(0.5))); end
\begin{array}{l}
\\
\left(\alpha \cdot \alpha\right) \cdot \left(u0 + \left(u0 \cdot u0\right) \cdot 0.5\right)
\end{array}
Initial program 52.9%
associate-*l*52.9%
sub-neg52.9%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 88.4%
associate-*r*88.4%
distribute-rgt-out88.4%
unpow288.4%
unpow288.4%
Simplified88.4%
Final simplification88.4%
(FPCore (alpha u0) :precision binary32 (* u0 (* alpha alpha)))
float code(float alpha, float u0) {
return u0 * (alpha * alpha);
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = u0 * (alpha * alpha)
end function
function code(alpha, u0) return Float32(u0 * Float32(alpha * alpha)) end
function tmp = code(alpha, u0) tmp = u0 * (alpha * alpha); end
\begin{array}{l}
\\
u0 \cdot \left(\alpha \cdot \alpha\right)
\end{array}
Initial program 52.9%
associate-*l*52.9%
sub-neg52.9%
log1p-def99.0%
Simplified99.0%
Taylor expanded in u0 around 0 75.7%
*-commutative75.7%
unpow275.7%
Simplified75.7%
Final simplification75.7%
herbie shell --seed 2023240
(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))))