
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (* PI (log (* alpha alpha))) (+ 1.0 (* (* t_0 cosTheta) cosTheta))))))
float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) - 1.0f;
return t_0 / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f + ((t_0 * cosTheta) * cosTheta)));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) - Float32(1.0)) return Float32(t_0 / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) + Float32(Float32(t_0 * cosTheta) * cosTheta)))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) - single(1.0); tmp = t_0 / ((single(pi) * log((alpha * alpha))) * (single(1.0) + ((t_0 * cosTheta) * cosTheta))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t_0}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(t_0 \cdot cosTheta\right) \cdot cosTheta\right)}
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 11 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (* PI (log (* alpha alpha))) (+ 1.0 (* (* t_0 cosTheta) cosTheta))))))
float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) - 1.0f;
return t_0 / ((((float) M_PI) * logf((alpha * alpha))) * (1.0f + ((t_0 * cosTheta) * cosTheta)));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) - Float32(1.0)) return Float32(t_0 / Float32(Float32(Float32(pi) * log(Float32(alpha * alpha))) * Float32(Float32(1.0) + Float32(Float32(t_0 * cosTheta) * cosTheta)))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) - single(1.0); tmp = t_0 / ((single(pi) * log((alpha * alpha))) * (single(1.0) + ((t_0 * cosTheta) * cosTheta))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t_0}{\left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right) \cdot \left(1 + \left(t_0 \cdot cosTheta\right) \cdot cosTheta\right)}
\end{array}
\end{array}
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (log (pow (* alpha alpha) PI)) (+ 1.0 (* cosTheta (* t_0 cosTheta)))))))
float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) - 1.0f;
return t_0 / (logf(powf((alpha * alpha), ((float) M_PI))) * (1.0f + (cosTheta * (t_0 * cosTheta))));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) - Float32(1.0)) return Float32(t_0 / Float32(log((Float32(alpha * alpha) ^ Float32(pi))) * Float32(Float32(1.0) + Float32(cosTheta * Float32(t_0 * cosTheta))))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) - single(1.0); tmp = t_0 / (log(((alpha * alpha) ^ single(pi))) * (single(1.0) + (cosTheta * (t_0 * cosTheta)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t_0}{\log \left({\left(\alpha \cdot \alpha\right)}^{\pi}\right) \cdot \left(1 + cosTheta \cdot \left(t_0 \cdot cosTheta\right)\right)}
\end{array}
\end{array}
Initial program 98.5%
add-log-exp98.5%
*-commutative98.5%
exp-to-pow98.6%
Applied egg-rr98.6%
Final simplification98.6%
(FPCore (cosTheta alpha)
:precision binary32
(let* ((t_0 (- (* alpha alpha) 1.0)))
(/
t_0
(* (+ 1.0 (* cosTheta (* t_0 cosTheta))) (* PI (log (* alpha alpha)))))))
float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) - 1.0f;
return t_0 / ((1.0f + (cosTheta * (t_0 * cosTheta))) * (((float) M_PI) * logf((alpha * alpha))));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) - Float32(1.0)) return Float32(t_0 / Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(t_0 * cosTheta))) * Float32(Float32(pi) * log(Float32(alpha * alpha))))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) - single(1.0); tmp = t_0 / ((single(1.0) + (cosTheta * (t_0 * cosTheta))) * (single(pi) * log((alpha * alpha)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t_0}{\left(1 + cosTheta \cdot \left(t_0 \cdot cosTheta\right)\right) \cdot \left(\pi \cdot \log \left(\alpha \cdot \alpha\right)\right)}
\end{array}
\end{array}
Initial program 98.5%
Final simplification98.5%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* 2.0 (* (- 1.0 (* cosTheta cosTheta)) (* PI (log alpha))))))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) - 1.0f) / (2.0f * ((1.0f - (cosTheta * cosTheta)) * (((float) M_PI) * logf(alpha))));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) - Float32(1.0)) / Float32(Float32(2.0) * Float32(Float32(Float32(1.0) - Float32(cosTheta * cosTheta)) * Float32(Float32(pi) * log(alpha))))) end
function tmp = code(cosTheta, alpha) tmp = ((alpha * alpha) - single(1.0)) / (single(2.0) * ((single(1.0) - (cosTheta * cosTheta)) * (single(pi) * log(alpha)))); end
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{2 \cdot \left(\left(1 - cosTheta \cdot cosTheta\right) \cdot \left(\pi \cdot \log \alpha\right)\right)}
\end{array}
Initial program 98.5%
pow298.5%
log-pow98.5%
*-commutative98.5%
Applied egg-rr98.5%
Taylor expanded in alpha around 0 97.3%
Simplified97.3%
Taylor expanded in alpha around 0 97.3%
*-commutative97.3%
associate-*l*97.3%
mul-1-neg97.3%
unsub-neg97.3%
unpow297.3%
*-commutative97.3%
Simplified97.3%
Final simplification97.3%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* 2.0 (* (log alpha) (* PI (- 1.0 (* cosTheta cosTheta)))))))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) - 1.0f) / (2.0f * (logf(alpha) * (((float) M_PI) * (1.0f - (cosTheta * cosTheta)))));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) - Float32(1.0)) / Float32(Float32(2.0) * Float32(log(alpha) * Float32(Float32(pi) * Float32(Float32(1.0) - Float32(cosTheta * cosTheta)))))) end
function tmp = code(cosTheta, alpha) tmp = ((alpha * alpha) - single(1.0)) / (single(2.0) * (log(alpha) * (single(pi) * (single(1.0) - (cosTheta * cosTheta))))); end
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{2 \cdot \left(\log \alpha \cdot \left(\pi \cdot \left(1 - cosTheta \cdot cosTheta\right)\right)\right)}
\end{array}
Initial program 98.5%
pow298.5%
log-pow98.5%
*-commutative98.5%
Applied egg-rr98.5%
Taylor expanded in alpha around 0 97.3%
Simplified97.3%
Taylor expanded in alpha around 0 97.3%
mul-1-neg97.3%
unpow297.3%
distribute-rgt-neg-out97.3%
Simplified97.3%
Final simplification97.3%
(FPCore (cosTheta alpha) :precision binary32 (/ -0.5 (* PI (* (log alpha) (- 1.0 (* cosTheta cosTheta))))))
float code(float cosTheta, float alpha) {
return -0.5f / (((float) M_PI) * (logf(alpha) * (1.0f - (cosTheta * cosTheta))));
}
function code(cosTheta, alpha) return Float32(Float32(-0.5) / Float32(Float32(pi) * Float32(log(alpha) * Float32(Float32(1.0) - Float32(cosTheta * cosTheta))))) end
function tmp = code(cosTheta, alpha) tmp = single(-0.5) / (single(pi) * (log(alpha) * (single(1.0) - (cosTheta * cosTheta)))); end
\begin{array}{l}
\\
\frac{-0.5}{\pi \cdot \left(\log \alpha \cdot \left(1 - cosTheta \cdot cosTheta\right)\right)}
\end{array}
Initial program 98.5%
pow298.5%
log-pow98.5%
*-commutative98.5%
Applied egg-rr98.5%
Taylor expanded in alpha around 0 66.8%
associate-*r*66.8%
mul-1-neg66.8%
unsub-neg66.8%
unpow266.8%
Simplified66.8%
Final simplification66.8%
(FPCore (cosTheta alpha) :precision binary32 (/ -0.5 (* (- 1.0 (* cosTheta cosTheta)) (* PI (log alpha)))))
float code(float cosTheta, float alpha) {
return -0.5f / ((1.0f - (cosTheta * cosTheta)) * (((float) M_PI) * logf(alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(-0.5) / Float32(Float32(Float32(1.0) - Float32(cosTheta * cosTheta)) * Float32(Float32(pi) * log(alpha)))) end
function tmp = code(cosTheta, alpha) tmp = single(-0.5) / ((single(1.0) - (cosTheta * cosTheta)) * (single(pi) * log(alpha))); end
\begin{array}{l}
\\
\frac{-0.5}{\left(1 - cosTheta \cdot cosTheta\right) \cdot \left(\pi \cdot \log \alpha\right)}
\end{array}
Initial program 98.5%
difference-of-sqr-198.1%
*-commutative98.1%
+-commutative98.1%
fma-neg98.1%
metadata-eval98.1%
associate-*r*98.1%
fma-udef98.1%
times-frac98.2%
sub-neg98.2%
metadata-eval98.2%
pow298.2%
log-pow98.3%
*-commutative98.3%
Applied egg-rr98.3%
Taylor expanded in alpha around 0 66.8%
*-commutative66.8%
associate-*l*66.8%
mul-1-neg66.8%
unsub-neg66.8%
unpow266.8%
*-commutative66.8%
Simplified66.8%
Final simplification66.8%
(FPCore (cosTheta alpha) :precision binary32 (/ (- (* alpha alpha) 1.0) (* (log alpha) (* PI 2.0))))
float code(float cosTheta, float alpha) {
return ((alpha * alpha) - 1.0f) / (logf(alpha) * (((float) M_PI) * 2.0f));
}
function code(cosTheta, alpha) return Float32(Float32(Float32(alpha * alpha) - Float32(1.0)) / Float32(log(alpha) * Float32(Float32(pi) * Float32(2.0)))) end
function tmp = code(cosTheta, alpha) tmp = ((alpha * alpha) - single(1.0)) / (log(alpha) * (single(pi) * single(2.0))); end
\begin{array}{l}
\\
\frac{\alpha \cdot \alpha - 1}{\log \alpha \cdot \left(\pi \cdot 2\right)}
\end{array}
Initial program 98.5%
pow298.5%
log-pow98.5%
*-commutative98.5%
Applied egg-rr98.5%
Taylor expanded in alpha around 0 97.3%
Simplified97.3%
Taylor expanded in cosTheta around 0 94.7%
associate-*r*94.7%
*-commutative94.7%
associate-*l*94.7%
Simplified94.7%
Final simplification94.7%
(FPCore (cosTheta alpha) :precision binary32 (* -0.5 (* (/ alpha (- (log alpha))) (/ alpha PI))))
float code(float cosTheta, float alpha) {
return -0.5f * ((alpha / -logf(alpha)) * (alpha / ((float) M_PI)));
}
function code(cosTheta, alpha) return Float32(Float32(-0.5) * Float32(Float32(alpha / Float32(-log(alpha))) * Float32(alpha / Float32(pi)))) end
function tmp = code(cosTheta, alpha) tmp = single(-0.5) * ((alpha / -log(alpha)) * (alpha / single(pi))); end
\begin{array}{l}
\\
-0.5 \cdot \left(\frac{\alpha}{-\log \alpha} \cdot \frac{\alpha}{\pi}\right)
\end{array}
Initial program 98.5%
Taylor expanded in cosTheta around 0 94.7%
Simplified94.7%
Taylor expanded in alpha around inf 3.6%
unpow23.6%
times-frac3.6%
log-rec3.6%
Simplified3.6%
Final simplification3.6%
(FPCore (cosTheta alpha) :precision binary32 (* -0.5 (/ (* alpha alpha) (* PI (- (log alpha))))))
float code(float cosTheta, float alpha) {
return -0.5f * ((alpha * alpha) / (((float) M_PI) * -logf(alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(-0.5) * Float32(Float32(alpha * alpha) / Float32(Float32(pi) * Float32(-log(alpha))))) end
function tmp = code(cosTheta, alpha) tmp = single(-0.5) * ((alpha * alpha) / (single(pi) * -log(alpha))); end
\begin{array}{l}
\\
-0.5 \cdot \frac{\alpha \cdot \alpha}{\pi \cdot \left(-\log \alpha\right)}
\end{array}
Initial program 98.5%
Taylor expanded in cosTheta around 0 94.7%
Simplified94.7%
Taylor expanded in alpha around inf 3.6%
unpow23.6%
*-commutative3.6%
log-rec3.6%
Simplified3.6%
Final simplification3.6%
(FPCore (cosTheta alpha) :precision binary32 (/ 0.5 (* (* cosTheta cosTheta) (* PI (log alpha)))))
float code(float cosTheta, float alpha) {
return 0.5f / ((cosTheta * cosTheta) * (((float) M_PI) * logf(alpha)));
}
function code(cosTheta, alpha) return Float32(Float32(0.5) / Float32(Float32(cosTheta * cosTheta) * Float32(Float32(pi) * log(alpha)))) end
function tmp = code(cosTheta, alpha) tmp = single(0.5) / ((cosTheta * cosTheta) * (single(pi) * log(alpha))); end
\begin{array}{l}
\\
\frac{0.5}{\left(cosTheta \cdot cosTheta\right) \cdot \left(\pi \cdot \log \alpha\right)}
\end{array}
Initial program 98.5%
pow298.5%
log-pow98.5%
*-commutative98.5%
Applied egg-rr98.5%
Taylor expanded in alpha around inf 1.9%
log-rec1.9%
unpow21.9%
Simplified1.9%
Taylor expanded in alpha around 0 1.9%
unpow21.9%
associate-*r*1.9%
*-commutative1.9%
associate-*r*1.9%
unpow21.9%
associate-*l*1.9%
unpow21.9%
*-commutative1.9%
Simplified1.9%
Final simplification1.9%
(FPCore (cosTheta alpha) :precision binary32 (let* ((t_0 (- (* alpha alpha) 1.0))) (/ t_0 (* (+ 1.0 (* cosTheta (* t_0 cosTheta))) (* PI (/ 0.0 0.0))))))
float code(float cosTheta, float alpha) {
float t_0 = (alpha * alpha) - 1.0f;
return t_0 / ((1.0f + (cosTheta * (t_0 * cosTheta))) * (((float) M_PI) * (0.0f / 0.0f)));
}
function code(cosTheta, alpha) t_0 = Float32(Float32(alpha * alpha) - Float32(1.0)) return Float32(t_0 / Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(t_0 * cosTheta))) * Float32(Float32(pi) * Float32(Float32(0.0) / Float32(0.0))))) end
function tmp = code(cosTheta, alpha) t_0 = (alpha * alpha) - single(1.0); tmp = t_0 / ((single(1.0) + (cosTheta * (t_0 * cosTheta))) * (single(pi) * (single(0.0) / single(0.0)))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \alpha \cdot \alpha - 1\\
\frac{t_0}{\left(1 + cosTheta \cdot \left(t_0 \cdot cosTheta\right)\right) \cdot \left(\pi \cdot \frac{0}{0}\right)}
\end{array}
\end{array}
Initial program 98.5%
log-prod98.5%
flip-+-0.0%
pow20.0%
pow2-0.0%
Applied egg-rr-0.0%
Simplified-0.0%
Final simplification-0.0%
herbie shell --seed 2023187
(FPCore (cosTheta alpha)
:name "GTR1 distribution"
:precision binary32
:pre (and (and (<= 0.0 cosTheta) (<= cosTheta 1.0)) (and (<= 0.0001 alpha) (<= alpha 1.0)))
(/ (- (* alpha alpha) 1.0) (* (* PI (log (* alpha alpha))) (+ 1.0 (* (* (- (* alpha alpha) 1.0) cosTheta) cosTheta)))))