
(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 8 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(alpha * Float32(alpha * Float32(-log1p(Float32(-u0))))) end
\begin{array}{l}
\\
\alpha \cdot \left(\alpha \cdot \left(-\mathsf{log1p}\left(-u0\right)\right)\right)
\end{array}
Initial program 54.6%
associate-*l*54.6%
sub-neg54.6%
log1p-def99.0%
Simplified99.0%
Final simplification99.0%
(FPCore (alpha u0) :precision binary32 (* (log1p (- u0)) (* alpha (- alpha))))
float code(float alpha, float u0) {
return log1pf(-u0) * (alpha * -alpha);
}
function code(alpha, u0) return Float32(log1p(Float32(-u0)) * Float32(alpha * Float32(-alpha))) end
\begin{array}{l}
\\
\mathsf{log1p}\left(-u0\right) \cdot \left(\alpha \cdot \left(-\alpha\right)\right)
\end{array}
Initial program 54.6%
associate-*l*54.6%
Simplified54.6%
Taylor expanded in alpha around 0 54.6%
mul-1-neg54.6%
*-commutative54.6%
distribute-rgt-neg-in54.6%
sub-neg54.6%
mul-1-neg54.6%
log1p-def99.0%
mul-1-neg99.0%
unpow299.0%
distribute-rgt-neg-in99.0%
Simplified99.0%
Final simplification99.0%
(FPCore (alpha u0)
:precision binary32
(let* ((t_0 (* (* u0 u0) (+ -0.5 (* u0 -0.3333333333333333)))))
(*
(* alpha alpha)
(/ (- (* u0 u0) (* t_0 (* u0 (* u0 -0.5)))) (+ u0 t_0)))))
float code(float alpha, float u0) {
float t_0 = (u0 * u0) * (-0.5f + (u0 * -0.3333333333333333f));
return (alpha * alpha) * (((u0 * u0) - (t_0 * (u0 * (u0 * -0.5f)))) / (u0 + t_0));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
real(4) :: t_0
t_0 = (u0 * u0) * ((-0.5e0) + (u0 * (-0.3333333333333333e0)))
code = (alpha * alpha) * (((u0 * u0) - (t_0 * (u0 * (u0 * (-0.5e0))))) / (u0 + t_0))
end function
function code(alpha, u0) t_0 = Float32(Float32(u0 * u0) * Float32(Float32(-0.5) + Float32(u0 * Float32(-0.3333333333333333)))) return Float32(Float32(alpha * alpha) * Float32(Float32(Float32(u0 * u0) - Float32(t_0 * Float32(u0 * Float32(u0 * Float32(-0.5))))) / Float32(u0 + t_0))) end
function tmp = code(alpha, u0) t_0 = (u0 * u0) * (single(-0.5) + (u0 * single(-0.3333333333333333))); tmp = (alpha * alpha) * (((u0 * u0) - (t_0 * (u0 * (u0 * single(-0.5))))) / (u0 + t_0)); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(u0 \cdot u0\right) \cdot \left(-0.5 + u0 \cdot -0.3333333333333333\right)\\
\left(\alpha \cdot \alpha\right) \cdot \frac{u0 \cdot u0 - t_0 \cdot \left(u0 \cdot \left(u0 \cdot -0.5\right)\right)}{u0 + t_0}
\end{array}
\end{array}
Initial program 54.6%
Taylor expanded in u0 around 0 91.8%
+-commutative91.8%
mul-1-neg91.8%
unsub-neg91.8%
cube-mult91.8%
unpow291.8%
associate-*r*91.8%
distribute-rgt-out91.8%
unpow291.8%
Simplified91.8%
flip--91.6%
*-commutative91.6%
*-commutative91.6%
*-commutative91.6%
Applied egg-rr91.6%
Taylor expanded in u0 around 0 92.9%
unpow292.9%
associate-*r*92.9%
Simplified92.9%
Final simplification92.9%
(FPCore (alpha u0) :precision binary32 (* alpha (* alpha (- u0 (* (* u0 u0) (+ -0.5 (* u0 -0.3333333333333333)))))))
float code(float alpha, float u0) {
return alpha * (alpha * (u0 - ((u0 * u0) * (-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) * ((-0.5e0) + (u0 * (-0.3333333333333333e0))))))
end function
function code(alpha, u0) return Float32(alpha * Float32(alpha * Float32(u0 - Float32(Float32(u0 * u0) * Float32(Float32(-0.5) + Float32(u0 * Float32(-0.3333333333333333))))))) end
function tmp = code(alpha, u0) tmp = alpha * (alpha * (u0 - ((u0 * u0) * (single(-0.5) + (u0 * single(-0.3333333333333333)))))); end
\begin{array}{l}
\\
\alpha \cdot \left(\alpha \cdot \left(u0 - \left(u0 \cdot u0\right) \cdot \left(-0.5 + u0 \cdot -0.3333333333333333\right)\right)\right)
\end{array}
Initial program 54.6%
associate-*l*54.6%
Simplified54.6%
Taylor expanded in u0 around 0 91.8%
+-commutative91.8%
mul-1-neg91.8%
unsub-neg91.8%
cube-mult91.8%
unpow291.8%
associate-*r*91.8%
distribute-rgt-out91.8%
unpow291.8%
Simplified91.8%
Final simplification91.8%
(FPCore (alpha u0) :precision binary32 (* (* alpha alpha) (- u0 (* (* u0 u0) (+ -0.5 (* u0 -0.3333333333333333))))))
float code(float alpha, float u0) {
return (alpha * alpha) * (u0 - ((u0 * u0) * (-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) * ((-0.5e0) + (u0 * (-0.3333333333333333e0)))))
end function
function code(alpha, u0) return Float32(Float32(alpha * alpha) * Float32(u0 - Float32(Float32(u0 * u0) * Float32(Float32(-0.5) + Float32(u0 * Float32(-0.3333333333333333)))))) end
function tmp = code(alpha, u0) tmp = (alpha * alpha) * (u0 - ((u0 * u0) * (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 \left(-0.5 + u0 \cdot -0.3333333333333333\right)\right)
\end{array}
Initial program 54.6%
Taylor expanded in u0 around 0 91.8%
+-commutative91.8%
mul-1-neg91.8%
unsub-neg91.8%
cube-mult91.8%
unpow291.8%
associate-*r*91.8%
distribute-rgt-out91.8%
unpow291.8%
Simplified91.8%
Final simplification91.8%
(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 54.6%
associate-*l*54.6%
Simplified54.6%
Taylor expanded in u0 around 0 87.7%
+-commutative87.7%
*-commutative87.7%
associate-*l*87.7%
distribute-lft-out87.7%
unpow287.7%
unpow287.7%
Simplified87.7%
Final simplification87.7%
(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(alpha * Float32(alpha * u0)) end
function tmp = code(alpha, u0) tmp = alpha * (alpha * u0); end
\begin{array}{l}
\\
\alpha \cdot \left(\alpha \cdot u0\right)
\end{array}
Initial program 54.6%
associate-*l*54.6%
Simplified54.6%
Taylor expanded in alpha around 0 54.6%
mul-1-neg54.6%
*-commutative54.6%
distribute-rgt-neg-in54.6%
sub-neg54.6%
mul-1-neg54.6%
log1p-def99.0%
mul-1-neg99.0%
unpow299.0%
distribute-rgt-neg-in99.0%
Simplified99.0%
Taylor expanded in u0 around 0 75.5%
*-commutative75.5%
unpow275.5%
associate-*r*75.5%
*-commutative75.5%
*-commutative75.5%
Simplified75.5%
Final simplification75.5%
(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 54.6%
associate-*l*54.6%
Simplified54.6%
Taylor expanded in u0 around 0 75.5%
*-commutative75.5%
unpow275.5%
Simplified75.5%
Final simplification75.5%
herbie shell --seed 2023287
(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))))