
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
(+ 1.0 c)
(*
(* (/ 1.0 (sqrt PI)) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta))
(exp (* (- cosTheta) cosTheta))))))
float code(float cosTheta, float c) {
return 1.0f / ((1.0f + c) + (((1.0f / sqrtf(((float) M_PI))) * (sqrtf(((1.0f - cosTheta) - cosTheta)) / cosTheta)) * expf((-cosTheta * cosTheta))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(Float32(1.0) + c) + Float32(Float32(Float32(Float32(1.0) / sqrt(Float32(pi))) * Float32(sqrt(Float32(Float32(Float32(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp(Float32(Float32(-cosTheta) * cosTheta))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / ((single(1.0) + c) + (((single(1.0) / sqrt(single(pi))) * (sqrt(((single(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp((-cosTheta * cosTheta)))); end
\begin{array}{l}
\\
\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 13 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
(+ 1.0 c)
(*
(* (/ 1.0 (sqrt PI)) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta))
(exp (* (- cosTheta) cosTheta))))))
float code(float cosTheta, float c) {
return 1.0f / ((1.0f + c) + (((1.0f / sqrtf(((float) M_PI))) * (sqrtf(((1.0f - cosTheta) - cosTheta)) / cosTheta)) * expf((-cosTheta * cosTheta))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(Float32(1.0) + c) + Float32(Float32(Float32(Float32(1.0) / sqrt(Float32(pi))) * Float32(sqrt(Float32(Float32(Float32(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp(Float32(Float32(-cosTheta) * cosTheta))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / ((single(1.0) + c) + (((single(1.0) / sqrt(single(pi))) * (sqrt(((single(1.0) - cosTheta) - cosTheta)) / cosTheta)) * exp((-cosTheta * cosTheta)))); end
\begin{array}{l}
\\
\frac{1}{\left(1 + c\right) + \left(\frac{1}{\sqrt{\pi}} \cdot \frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta}\right) \cdot e^{\left(-cosTheta\right) \cdot cosTheta}}
\end{array}
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(/ (sqrt (- (- 1.0 cosTheta) cosTheta)) (* cosTheta (sqrt PI)))
(pow (exp cosTheta) cosTheta))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((sqrtf(((1.0f - cosTheta) - cosTheta)) / (cosTheta * sqrtf(((float) M_PI)))) / powf(expf(cosTheta), cosTheta))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(sqrt(Float32(Float32(Float32(1.0) - cosTheta) - cosTheta)) / Float32(cosTheta * sqrt(Float32(pi)))) / (exp(cosTheta) ^ cosTheta))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((sqrt(((single(1.0) - cosTheta) - cosTheta)) / (cosTheta * sqrt(single(pi)))) / (exp(cosTheta) ^ cosTheta)))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{\frac{\sqrt{\left(1 - cosTheta\right) - cosTheta}}{cosTheta \cdot \sqrt{\pi}}}{{\left(e^{cosTheta}\right)}^{cosTheta}}\right)}
\end{array}
Initial program 97.9%
associate-+l+97.8%
distribute-lft-neg-out97.8%
exp-neg97.8%
sqr-neg97.8%
associate-*r/97.8%
associate-/l*97.8%
/-rgt-identity97.8%
*-commutative97.8%
Simplified98.7%
Final simplification98.7%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
(+ 1.0 c)
(*
(/ (sqrt (- 1.0 (+ cosTheta cosTheta))) (* cosTheta (sqrt PI)))
(exp (* cosTheta (- cosTheta)))))))
float code(float cosTheta, float c) {
return 1.0f / ((1.0f + c) + ((sqrtf((1.0f - (cosTheta + cosTheta))) / (cosTheta * sqrtf(((float) M_PI)))) * expf((cosTheta * -cosTheta))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(Float32(1.0) + c) + Float32(Float32(sqrt(Float32(Float32(1.0) - Float32(cosTheta + cosTheta))) / Float32(cosTheta * sqrt(Float32(pi)))) * exp(Float32(cosTheta * Float32(-cosTheta)))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / ((single(1.0) + c) + ((sqrt((single(1.0) - (cosTheta + cosTheta))) / (cosTheta * sqrt(single(pi)))) * exp((cosTheta * -cosTheta)))); end
\begin{array}{l}
\\
\frac{1}{\left(1 + c\right) + \frac{\sqrt{1 - \left(cosTheta + cosTheta\right)}}{cosTheta \cdot \sqrt{\pi}} \cdot e^{cosTheta \cdot \left(-cosTheta\right)}}
\end{array}
Initial program 97.9%
frac-times98.7%
*-un-lft-identity98.7%
associate--l-98.6%
Applied egg-rr98.6%
Final simplification98.6%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
(+ 1.0 c)
(*
(exp (* cosTheta (- cosTheta)))
(+
(+ 1.0 (/ (sqrt (/ (- 1.0 (+ cosTheta cosTheta)) PI)) cosTheta))
-1.0)))))
float code(float cosTheta, float c) {
return 1.0f / ((1.0f + c) + (expf((cosTheta * -cosTheta)) * ((1.0f + (sqrtf(((1.0f - (cosTheta + cosTheta)) / ((float) M_PI))) / cosTheta)) + -1.0f)));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(Float32(1.0) + c) + Float32(exp(Float32(cosTheta * Float32(-cosTheta))) * Float32(Float32(Float32(1.0) + Float32(sqrt(Float32(Float32(Float32(1.0) - Float32(cosTheta + cosTheta)) / Float32(pi))) / cosTheta)) + Float32(-1.0))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / ((single(1.0) + c) + (exp((cosTheta * -cosTheta)) * ((single(1.0) + (sqrt(((single(1.0) - (cosTheta + cosTheta)) / single(pi))) / cosTheta)) + single(-1.0)))); end
\begin{array}{l}
\\
\frac{1}{\left(1 + c\right) + e^{cosTheta \cdot \left(-cosTheta\right)} \cdot \left(\left(1 + \frac{\sqrt{\frac{1 - \left(cosTheta + cosTheta\right)}{\pi}}}{cosTheta}\right) + -1\right)}
\end{array}
Initial program 97.9%
frac-times98.7%
*-un-lft-identity98.7%
associate--l-98.6%
Applied egg-rr98.6%
*-un-lft-identity98.6%
associate-/r*98.0%
count-298.0%
sqrt-div98.1%
count-298.1%
Applied egg-rr98.1%
expm1-log1p-u90.5%
expm1-udef90.5%
log1p-udef90.5%
add-exp-log98.1%
Applied egg-rr98.1%
Final simplification98.1%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
(+ 1.0 c)
(*
(exp (* cosTheta (- cosTheta)))
(/ (sqrt (/ (- 1.0 (+ cosTheta cosTheta)) PI)) cosTheta)))))
float code(float cosTheta, float c) {
return 1.0f / ((1.0f + c) + (expf((cosTheta * -cosTheta)) * (sqrtf(((1.0f - (cosTheta + cosTheta)) / ((float) M_PI))) / cosTheta)));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(Float32(1.0) + c) + Float32(exp(Float32(cosTheta * Float32(-cosTheta))) * Float32(sqrt(Float32(Float32(Float32(1.0) - Float32(cosTheta + cosTheta)) / Float32(pi))) / cosTheta)))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / ((single(1.0) + c) + (exp((cosTheta * -cosTheta)) * (sqrt(((single(1.0) - (cosTheta + cosTheta)) / single(pi))) / cosTheta))); end
\begin{array}{l}
\\
\frac{1}{\left(1 + c\right) + e^{cosTheta \cdot \left(-cosTheta\right)} \cdot \frac{\sqrt{\frac{1 - \left(cosTheta + cosTheta\right)}{\pi}}}{cosTheta}}
\end{array}
Initial program 97.9%
frac-times98.7%
*-un-lft-identity98.7%
associate--l-98.6%
Applied egg-rr98.6%
expm1-log1p-u90.5%
associate-/r*90.5%
count-290.5%
sqrt-div90.5%
count-290.5%
Applied egg-rr90.5%
expm1-log1p-u98.1%
Applied egg-rr98.1%
Final simplification98.1%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(*
(/ (exp (* cosTheta (- cosTheta))) cosTheta)
(sqrt (/ (+ 1.0 (* cosTheta -2.0)) PI))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + ((expf((cosTheta * -cosTheta)) / cosTheta) * sqrtf(((1.0f + (cosTheta * -2.0f)) / ((float) M_PI)))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(Float32(exp(Float32(cosTheta * Float32(-cosTheta))) / cosTheta) * sqrt(Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(-2.0))) / Float32(pi)))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + ((exp((cosTheta * -cosTheta)) / cosTheta) * sqrt(((single(1.0) + (cosTheta * single(-2.0))) / single(pi))))); end
\begin{array}{l}
\\
\frac{1}{1 + \frac{e^{cosTheta \cdot \left(-cosTheta\right)}}{cosTheta} \cdot \sqrt{\frac{1 + cosTheta \cdot -2}{\pi}}}
\end{array}
Initial program 97.9%
frac-times98.7%
*-un-lft-identity98.7%
associate--l-98.6%
Applied egg-rr98.6%
*-un-lft-identity98.6%
associate-/r*98.0%
count-298.0%
sqrt-div98.1%
count-298.1%
Applied egg-rr98.1%
Taylor expanded in c around 0 97.5%
mul-1-neg97.5%
unpow297.5%
cancel-sign-sub-inv97.5%
metadata-eval97.5%
Simplified97.5%
Final simplification97.5%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(- 1.0 cosTheta)
(* cosTheta (* (sqrt PI) (exp (* cosTheta cosTheta)))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((1.0f - cosTheta) / (cosTheta * (sqrtf(((float) M_PI)) * expf((cosTheta * cosTheta)))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(1.0) - cosTheta) / Float32(cosTheta * Float32(sqrt(Float32(pi)) * exp(Float32(cosTheta * cosTheta)))))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((single(1.0) - cosTheta) / (cosTheta * (sqrt(single(pi)) * exp((cosTheta * cosTheta))))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{1 - cosTheta}{cosTheta \cdot \left(\sqrt{\pi} \cdot e^{cosTheta \cdot cosTheta}\right)}\right)}
\end{array}
Initial program 97.9%
associate-+l+97.8%
associate-*l*97.8%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.4%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around 0 96.2%
neg-mul-196.2%
sub-neg96.2%
Simplified96.2%
Taylor expanded in cosTheta around inf 96.2%
associate-*l*96.2%
unpow296.2%
exp-prod96.2%
*-commutative96.2%
exp-prod96.2%
Simplified96.2%
Final simplification96.2%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (+ 1.0 (+ c (/ (- 1.0 cosTheta) (* (sqrt PI) (+ cosTheta (pow cosTheta 3.0))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((1.0f - cosTheta) / (sqrtf(((float) M_PI)) * (cosTheta + powf(cosTheta, 3.0f))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(1.0) - cosTheta) / Float32(sqrt(Float32(pi)) * Float32(cosTheta + (cosTheta ^ Float32(3.0)))))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((single(1.0) - cosTheta) / (sqrt(single(pi)) * (cosTheta + (cosTheta ^ single(3.0))))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{1 - cosTheta}{\sqrt{\pi} \cdot \left(cosTheta + {cosTheta}^{3}\right)}\right)}
\end{array}
Initial program 97.9%
associate-+l+97.8%
associate-*l*97.8%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.4%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around 0 96.2%
neg-mul-196.2%
sub-neg96.2%
Simplified96.2%
Taylor expanded in cosTheta around 0 96.2%
Final simplification96.2%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (+ 1.0 (* (sqrt (/ 1.0 PI)) (+ -1.0 (/ 1.0 cosTheta))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (sqrtf((1.0f / ((float) M_PI))) * (-1.0f + (1.0f / cosTheta))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(sqrt(Float32(Float32(1.0) / Float32(pi))) * Float32(Float32(-1.0) + Float32(Float32(1.0) / cosTheta))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (sqrt((single(1.0) / single(pi))) * (single(-1.0) + (single(1.0) / cosTheta)))); end
\begin{array}{l}
\\
\frac{1}{1 + \sqrt{\frac{1}{\pi}} \cdot \left(-1 + \frac{1}{cosTheta}\right)}
\end{array}
Initial program 97.9%
associate-+l+97.8%
associate-*l*97.8%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.4%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around 0 95.1%
distribute-rgt-out95.0%
+-commutative95.0%
Simplified95.0%
Taylor expanded in c around 0 95.0%
Final simplification95.0%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (+ 1.0 (+ c (/ (+ -1.0 (/ 1.0 cosTheta)) (sqrt PI))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((-1.0f + (1.0f / cosTheta)) / sqrtf(((float) M_PI)))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(-1.0) + Float32(Float32(1.0) / cosTheta)) / sqrt(Float32(pi)))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((single(-1.0) + (single(1.0) / cosTheta)) / sqrt(single(pi))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{-1 + \frac{1}{cosTheta}}{\sqrt{\pi}}\right)}
\end{array}
Initial program 97.9%
associate-+l+97.8%
associate-*l*97.8%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.4%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around 0 95.1%
distribute-rgt-out95.0%
+-commutative95.0%
Simplified95.0%
distribute-lft-in95.1%
sqrt-div95.1%
metadata-eval95.1%
sqrt-div95.1%
metadata-eval95.1%
Applied egg-rr95.1%
distribute-lft-in95.0%
associate-*l/95.7%
*-lft-identity95.7%
+-commutative95.7%
Simplified95.7%
Final simplification95.7%
(FPCore (cosTheta c) :precision binary32 (/ 1.0 (+ 1.0 (+ c (/ (- 1.0 cosTheta) (* cosTheta (sqrt PI)))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((1.0f - cosTheta) / (cosTheta * sqrtf(((float) M_PI))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(1.0) - cosTheta) / Float32(cosTheta * sqrt(Float32(pi))))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((single(1.0) - cosTheta) / (cosTheta * sqrt(single(pi)))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{1 - cosTheta}{cosTheta \cdot \sqrt{\pi}}\right)}
\end{array}
Initial program 97.9%
associate-+l+97.8%
associate-*l*97.8%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.4%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around 0 96.2%
neg-mul-196.2%
sub-neg96.2%
Simplified96.2%
Taylor expanded in cosTheta around 0 95.9%
Final simplification95.9%
(FPCore (cosTheta c) :precision binary32 (* cosTheta (sqrt PI)))
float code(float cosTheta, float c) {
return cosTheta * sqrtf(((float) M_PI));
}
function code(cosTheta, c) return Float32(cosTheta * sqrt(Float32(pi))) end
function tmp = code(cosTheta, c) tmp = cosTheta * sqrt(single(pi)); end
\begin{array}{l}
\\
cosTheta \cdot \sqrt{\pi}
\end{array}
Initial program 97.9%
frac-times98.7%
*-un-lft-identity98.7%
associate--l-98.6%
Applied egg-rr98.6%
Taylor expanded in cosTheta around 0 93.1%
Final simplification93.1%
(FPCore (cosTheta c) :precision binary32 (- 1.0 c))
float code(float cosTheta, float c) {
return 1.0f - c;
}
real(4) function code(costheta, c)
real(4), intent (in) :: costheta
real(4), intent (in) :: c
code = 1.0e0 - c
end function
function code(cosTheta, c) return Float32(Float32(1.0) - c) end
function tmp = code(cosTheta, c) tmp = single(1.0) - c; end
\begin{array}{l}
\\
1 - c
\end{array}
Initial program 97.9%
associate-+l+97.8%
associate-*l*97.8%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.4%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around inf 10.6%
Taylor expanded in c around 0 10.6%
mul-1-neg10.6%
sub-neg10.6%
Simplified10.6%
Final simplification10.6%
(FPCore (cosTheta c) :precision binary32 1.0)
float code(float cosTheta, float c) {
return 1.0f;
}
real(4) function code(costheta, c)
real(4), intent (in) :: costheta
real(4), intent (in) :: c
code = 1.0e0
end function
function code(cosTheta, c) return Float32(1.0) end
function tmp = code(cosTheta, c) tmp = single(1.0); end
\begin{array}{l}
\\
1
\end{array}
Initial program 97.9%
associate-+l+97.8%
associate-*l*97.8%
associate-*l/98.4%
*-lft-identity98.4%
associate-/r/98.4%
associate-/l/98.6%
Simplified98.6%
Taylor expanded in cosTheta around inf 10.6%
Taylor expanded in c around 0 10.6%
Final simplification10.6%
herbie shell --seed 2023275
(FPCore (cosTheta c)
:name "Beckmann Sample, normalization factor"
:precision binary32
:pre (and (and (< 0.0 cosTheta) (< cosTheta 0.9999)) (and (< -1.0 c) (< c 1.0)))
(/ 1.0 (+ (+ 1.0 c) (* (* (/ 1.0 (sqrt PI)) (/ (sqrt (- (- 1.0 cosTheta) cosTheta)) cosTheta)) (exp (* (- cosTheta) cosTheta))))))