
(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(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 57.5%
associate-*l*57.5%
sub-neg57.5%
log1p-def99.1%
Simplified99.1%
Final simplification99.1%
(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 57.5%
associate-*l*57.5%
Simplified57.5%
Taylor expanded in u0 around 0 92.0%
*-commutative92.0%
associate-*r*92.0%
associate-*r*92.0%
distribute-rgt-out92.0%
distribute-lft-out91.9%
unpow291.9%
cube-mult91.9%
unpow291.9%
associate-*r*91.9%
distribute-rgt-out91.9%
unpow291.9%
Simplified91.9%
Final simplification91.9%
(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 57.5%
associate-*l*57.5%
Simplified57.5%
Taylor expanded in u0 around 0 92.0%
+-commutative92.0%
mul-1-neg92.0%
unsub-neg92.0%
*-commutative92.0%
*-commutative92.0%
unpow392.0%
unpow292.0%
associate-*l*92.0%
distribute-lft-out92.0%
unpow292.0%
Simplified92.0%
Final simplification92.0%
(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 57.5%
associate-*l*57.5%
Simplified57.5%
Taylor expanded in u0 around 0 87.5%
+-commutative87.5%
associate-*r*87.5%
distribute-rgt-out87.5%
unpow287.5%
*-commutative87.5%
unpow287.5%
Simplified87.5%
Final simplification87.5%
(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(alpha * Float32(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}
\\
\alpha \cdot \left(\alpha \cdot \left(u0 - \left(u0 \cdot u0\right) \cdot -0.5\right)\right)
\end{array}
Initial program 57.5%
associate-*l*57.5%
Simplified57.5%
Taylor expanded in u0 around 0 87.6%
+-commutative87.6%
mul-1-neg87.6%
unsub-neg87.6%
unpow287.6%
Simplified87.6%
Final simplification87.6%
(FPCore (alpha u0) :precision binary32 (* alpha (* u0 (- alpha (* alpha (* u0 -0.5))))))
float code(float alpha, float u0) {
return alpha * (u0 * (alpha - (alpha * (u0 * -0.5f))));
}
real(4) function code(alpha, u0)
real(4), intent (in) :: alpha
real(4), intent (in) :: u0
code = alpha * (u0 * (alpha - (alpha * (u0 * (-0.5e0)))))
end function
function code(alpha, u0) return Float32(alpha * Float32(u0 * Float32(alpha - Float32(alpha * Float32(u0 * Float32(-0.5)))))) end
function tmp = code(alpha, u0) tmp = alpha * (u0 * (alpha - (alpha * (u0 * single(-0.5))))); end
\begin{array}{l}
\\
\alpha \cdot \left(u0 \cdot \left(\alpha - \alpha \cdot \left(u0 \cdot -0.5\right)\right)\right)
\end{array}
Initial program 57.5%
associate-*l*57.5%
Simplified57.5%
Taylor expanded in u0 around 0 92.0%
+-commutative92.0%
mul-1-neg92.0%
unsub-neg92.0%
*-commutative92.0%
*-commutative92.0%
unpow392.0%
unpow292.0%
associate-*l*92.0%
distribute-lft-out92.0%
unpow292.0%
Simplified92.0%
Taylor expanded in u0 around 0 87.5%
+-commutative87.5%
mul-1-neg87.5%
unsub-neg87.5%
associate-*r*87.5%
*-commutative87.5%
unpow287.5%
associate-*l*87.5%
associate-*l*87.5%
distribute-lft-out--87.6%
Simplified87.6%
Final simplification87.6%
(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 57.5%
associate-*l*57.5%
Simplified57.5%
Taylor expanded in u0 around 0 87.5%
+-commutative87.5%
associate-*r*87.5%
distribute-rgt-out87.5%
unpow287.5%
*-commutative87.5%
unpow287.5%
Simplified87.5%
Taylor expanded in u0 around 0 74.0%
unpow274.0%
*-commutative74.0%
associate-*l*74.0%
Simplified74.0%
Final simplification74.0%
herbie shell --seed 2023214
(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))))