
(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 98.0%
associate-+l+98.0%
distribute-lft-neg-out98.0%
exp-neg98.0%
sqr-neg98.0%
associate-*r/98.0%
associate-/l*98.0%
/-rgt-identity98.0%
*-commutative98.0%
Simplified98.6%
Final simplification98.6%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(/ (sqrt (fma cosTheta -2.0 1.0)) cosTheta)
(* (sqrt PI) (exp (* cosTheta cosTheta))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((sqrtf(fmaf(cosTheta, -2.0f, 1.0f)) / 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(sqrt(fma(cosTheta, Float32(-2.0), Float32(1.0))) / cosTheta) / Float32(sqrt(Float32(pi)) * exp(Float32(cosTheta * cosTheta))))))) end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{\frac{\sqrt{\mathsf{fma}\left(cosTheta, -2, 1\right)}}{cosTheta}}{\sqrt{\pi} \cdot e^{cosTheta \cdot cosTheta}}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*98.0%
associate-*l/98.6%
*-lft-identity98.6%
associate-/l*98.7%
/-rgt-identity98.7%
associate-/l*98.7%
Simplified98.6%
Final simplification98.6%
(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(Float32(sqrt(Float32(Float32(1.0) - Float32(cosTheta + cosTheta))) / 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{\frac{\sqrt{1 - \left(cosTheta + cosTheta\right)}}{cosTheta}}{\sqrt{\pi}} \cdot e^{cosTheta \cdot \left(-cosTheta\right)}}
\end{array}
Initial program 98.0%
associate-*l/98.6%
*-un-lft-identity98.6%
associate--l-98.5%
Applied egg-rr98.5%
Final simplification98.5%
(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 98.0%
frac-times98.6%
*-un-lft-identity98.6%
associate-/r*98.1%
associate--l-98.1%
Applied egg-rr98.1%
sqrt-undiv98.2%
Applied egg-rr98.2%
Final simplification98.2%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(/
(sqrt (/ (+ 1.0 (* cosTheta -2.0)) PI))
(* cosTheta (exp (* cosTheta cosTheta)))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (sqrtf(((1.0f + (cosTheta * -2.0f)) / ((float) M_PI))) / (cosTheta * expf((cosTheta * cosTheta)))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(sqrt(Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(-2.0))) / Float32(pi))) / Float32(cosTheta * exp(Float32(cosTheta * cosTheta)))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (sqrt(((single(1.0) + (cosTheta * single(-2.0))) / single(pi))) / (cosTheta * exp((cosTheta * cosTheta))))); end
\begin{array}{l}
\\
\frac{1}{1 + \frac{\sqrt{\frac{1 + cosTheta \cdot -2}{\pi}}}{cosTheta \cdot e^{cosTheta \cdot cosTheta}}}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*98.0%
associate-*l/98.6%
*-lft-identity98.6%
associate-/r/98.6%
associate-/l/98.6%
Simplified98.5%
Taylor expanded in c around 0 96.9%
un-div-inv96.9%
*-commutative96.9%
*-commutative96.9%
unpow296.9%
Applied egg-rr96.9%
Final simplification96.9%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(/ (+ (- 1.0 cosTheta) (* (* cosTheta cosTheta) -0.5)) cosTheta)
(* (sqrt PI) (+ 1.0 (* cosTheta cosTheta))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((((1.0f - cosTheta) + ((cosTheta * cosTheta) * -0.5f)) / cosTheta) / (sqrtf(((float) M_PI)) * (1.0f + (cosTheta * cosTheta))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(Float32(Float32(1.0) - cosTheta) + Float32(Float32(cosTheta * cosTheta) * Float32(-0.5))) / cosTheta) / Float32(sqrt(Float32(pi)) * Float32(Float32(1.0) + Float32(cosTheta * cosTheta))))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((((single(1.0) - cosTheta) + ((cosTheta * cosTheta) * single(-0.5))) / cosTheta) / (sqrt(single(pi)) * (single(1.0) + (cosTheta * cosTheta)))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{\frac{\left(1 - cosTheta\right) + \left(cosTheta \cdot cosTheta\right) \cdot -0.5}{cosTheta}}{\sqrt{\pi} \cdot \left(1 + cosTheta \cdot cosTheta\right)}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*98.0%
associate-*l/98.6%
*-lft-identity98.6%
associate-/l*98.7%
/-rgt-identity98.7%
associate-/l*98.7%
Simplified98.6%
Taylor expanded in cosTheta around 0 96.7%
distribute-rgt1-in96.7%
unpow296.7%
Simplified96.7%
Taylor expanded in cosTheta around 0 95.7%
neg-mul-194.1%
associate-+r+94.1%
sub-neg94.1%
*-commutative94.1%
unpow294.1%
Simplified95.7%
Final simplification95.7%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(/ (+ (- 1.0 cosTheta) (* (* cosTheta cosTheta) -0.5)) cosTheta)
(sqrt PI))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + ((((1.0f - cosTheta) + ((cosTheta * cosTheta) * -0.5f)) / cosTheta) / sqrtf(((float) M_PI)))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(Float32(Float32(1.0) - cosTheta) + Float32(Float32(cosTheta * cosTheta) * Float32(-0.5))) / cosTheta) / sqrt(Float32(pi)))))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (c + ((((single(1.0) - cosTheta) + ((cosTheta * cosTheta) * single(-0.5))) / cosTheta) / sqrt(single(pi))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{\frac{\left(1 - cosTheta\right) + \left(cosTheta \cdot cosTheta\right) \cdot -0.5}{cosTheta}}{\sqrt{\pi}}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*98.0%
associate-*l/98.6%
*-lft-identity98.6%
associate-/l*98.7%
/-rgt-identity98.7%
associate-/l*98.7%
Simplified98.6%
Taylor expanded in cosTheta around 0 94.1%
Taylor expanded in cosTheta around 0 94.1%
neg-mul-194.1%
associate-+r+94.1%
sub-neg94.1%
*-commutative94.1%
unpow294.1%
Simplified94.1%
Final simplification94.1%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(+
c
(/
(/ (- 1.0 cosTheta) cosTheta)
(* (sqrt PI) (+ 1.0 (* cosTheta cosTheta))))))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + (c + (((1.0f - cosTheta) / cosTheta) / (sqrtf(((float) M_PI)) * (1.0f + (cosTheta * cosTheta))))));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(c + Float32(Float32(Float32(Float32(1.0) - cosTheta) / cosTheta) / Float32(sqrt(Float32(pi)) * Float32(Float32(1.0) + 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)) * (single(1.0) + (cosTheta * cosTheta)))))); end
\begin{array}{l}
\\
\frac{1}{1 + \left(c + \frac{\frac{1 - cosTheta}{cosTheta}}{\sqrt{\pi} \cdot \left(1 + cosTheta \cdot cosTheta\right)}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*98.0%
associate-*l/98.6%
*-lft-identity98.6%
associate-/l*98.7%
/-rgt-identity98.7%
associate-/l*98.7%
Simplified98.6%
Taylor expanded in cosTheta around 0 96.7%
distribute-rgt1-in96.7%
unpow296.7%
Simplified96.7%
Taylor expanded in cosTheta around 0 94.3%
neg-mul-194.3%
sub-neg94.3%
Simplified94.3%
Final simplification94.3%
(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 98.0%
associate-+l+98.0%
associate-*l*98.0%
associate-*l/98.6%
*-lft-identity98.6%
associate-/r/98.6%
associate-/l/98.6%
Simplified98.5%
Taylor expanded in cosTheta around 0 94.3%
neg-mul-194.3%
sub-neg94.3%
Simplified94.3%
Taylor expanded in cosTheta around 0 93.8%
Final simplification93.8%
(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(Float32(1.0) - cosTheta) / 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{\frac{1 - cosTheta}{cosTheta}}{\sqrt{\pi}}\right)}
\end{array}
Initial program 98.0%
associate-+l+98.0%
associate-*l*98.0%
associate-*l/98.6%
*-lft-identity98.6%
associate-/l*98.7%
/-rgt-identity98.7%
associate-/l*98.7%
Simplified98.6%
Taylor expanded in cosTheta around 0 94.1%
Taylor expanded in cosTheta around 0 93.9%
neg-mul-194.3%
sub-neg94.3%
Simplified93.9%
Final simplification93.9%
(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 98.0%
associate-*l/98.6%
*-un-lft-identity98.6%
associate--l-98.5%
Applied egg-rr98.5%
Taylor expanded in cosTheta around 0 91.3%
Final simplification91.3%
(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 98.0%
associate-+l+98.0%
distribute-lft-neg-out98.0%
exp-neg98.0%
sqr-neg98.0%
associate-*r/98.0%
associate-/l*98.0%
/-rgt-identity98.0%
*-commutative98.0%
Simplified98.6%
Taylor expanded in cosTheta around inf 11.3%
Taylor expanded in c around 0 11.3%
+-commutative11.3%
mul-1-neg11.3%
unsub-neg11.3%
Simplified11.3%
Final simplification11.3%
(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 98.0%
associate-+l+98.0%
distribute-lft-neg-out98.0%
exp-neg98.0%
sqr-neg98.0%
associate-*r/98.0%
associate-/l*98.0%
/-rgt-identity98.0%
*-commutative98.0%
Simplified98.6%
Taylor expanded in cosTheta around inf 11.3%
Taylor expanded in c around 0 11.3%
Final simplification11.3%
herbie shell --seed 2023268
(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))))))