
(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 9 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)))
(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 97.7%
frac-times98.7%
*-un-lft-identity98.7%
associate--r+98.7%
Applied egg-rr98.7%
Final simplification98.7%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
1.0
(/
(*
(pow (exp cosTheta) (- cosTheta))
(sqrt (/ (+ 1.0 (* cosTheta -2.0)) PI)))
cosTheta))))
float code(float cosTheta, float c) {
return 1.0f / (1.0f + ((powf(expf(cosTheta), -cosTheta) * sqrtf(((1.0f + (cosTheta * -2.0f)) / ((float) M_PI)))) / cosTheta));
}
function code(cosTheta, c) return Float32(Float32(1.0) / Float32(Float32(1.0) + Float32(Float32((exp(cosTheta) ^ Float32(-cosTheta)) * sqrt(Float32(Float32(Float32(1.0) + Float32(cosTheta * Float32(-2.0))) / Float32(pi)))) / cosTheta))) end
function tmp = code(cosTheta, c) tmp = single(1.0) / (single(1.0) + (((exp(cosTheta) ^ -cosTheta) * sqrt(((single(1.0) + (cosTheta * single(-2.0))) / single(pi)))) / cosTheta)); end
\begin{array}{l}
\\
\frac{1}{1 + \frac{{\left(e^{cosTheta}\right)}^{\left(-cosTheta\right)} \cdot \sqrt{\frac{1 + cosTheta \cdot -2}{\pi}}}{cosTheta}}
\end{array}
Initial program 97.7%
Taylor expanded in c around 0 97.7%
associate-*l/98.1%
mul-1-neg98.1%
unpow298.1%
distribute-rgt-neg-out98.1%
exp-prod98.1%
cancel-sign-sub-inv98.1%
metadata-eval98.1%
Applied egg-rr98.1%
Final simplification98.1%
(FPCore (cosTheta c)
:precision binary32
(/
1.0
(+
(+ 1.0 c)
(*
(exp (* cosTheta (- cosTheta)))
(/ (sqrt (/ (+ 1.0 (* cosTheta -2.0)) PI)) cosTheta)))))
float code(float cosTheta, float c) {
return 1.0f / ((1.0f + c) + (expf((cosTheta * -cosTheta)) * (sqrtf(((1.0f + (cosTheta * -2.0f)) / ((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 * Float32(-2.0))) / 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 * single(-2.0))) / single(pi))) / cosTheta))); end
\begin{array}{l}
\\
\frac{1}{\left(1 + c\right) + e^{cosTheta \cdot \left(-cosTheta\right)} \cdot \frac{\sqrt{\frac{1 + cosTheta \cdot -2}{\pi}}}{cosTheta}}
\end{array}
Initial program 97.7%
frac-times98.7%
*-un-lft-identity98.7%
associate--r+98.7%
Applied egg-rr98.7%
*-un-lft-identity98.7%
associate-/r*98.0%
count-298.0%
sqrt-div98.1%
cancel-sign-sub-inv98.1%
metadata-eval98.1%
Applied egg-rr98.1%
*-lft-identity98.1%
metadata-eval98.1%
cancel-sign-sub-inv98.1%
cancel-sign-sub-inv98.1%
metadata-eval98.1%
*-commutative98.1%
Simplified98.1%
Final simplification98.1%
(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 97.7%
associate-+l+97.7%
*-commutative97.7%
associate-*r*97.7%
*-commutative97.7%
associate-/r/98.0%
Simplified98.7%
Taylor expanded in cosTheta around 0 96.5%
neg-mul-196.5%
sub-neg96.5%
Simplified96.5%
Taylor expanded in cosTheta around 0 96.5%
distribute-rgt-out96.5%
Simplified96.5%
Final simplification96.5%
(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 97.7%
Taylor expanded in c around 0 97.7%
associate-*l/98.1%
mul-1-neg98.1%
unpow298.1%
distribute-rgt-neg-out98.1%
exp-prod98.1%
cancel-sign-sub-inv98.1%
metadata-eval98.1%
Applied egg-rr98.1%
associate-*r/98.0%
exp-prod98.0%
distribute-rgt-neg-in98.0%
unpow298.0%
rec-exp98.1%
unpow298.1%
exp-prod98.1%
times-frac98.1%
*-lft-identity98.1%
+-commutative98.1%
*-commutative98.1%
fma-def98.1%
*-commutative98.1%
Simplified98.1%
add-log-exp98.1%
Applied egg-rr98.1%
Taylor expanded in cosTheta around 0 95.2%
distribute-rgt-out95.2%
Simplified95.2%
Final simplification95.2%
(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 97.7%
frac-times98.7%
*-un-lft-identity98.7%
associate--r+98.7%
Applied egg-rr98.7%
Taylor expanded in cosTheta around 0 94.0%
Final simplification94.0%
(FPCore (cosTheta c) :precision binary32 (* c (* PI (* cosTheta (- cosTheta)))))
float code(float cosTheta, float c) {
return c * (((float) M_PI) * (cosTheta * -cosTheta));
}
function code(cosTheta, c) return Float32(c * Float32(Float32(pi) * Float32(cosTheta * Float32(-cosTheta)))) end
function tmp = code(cosTheta, c) tmp = c * (single(pi) * (cosTheta * -cosTheta)); end
\begin{array}{l}
\\
c \cdot \left(\pi \cdot \left(cosTheta \cdot \left(-cosTheta\right)\right)\right)
\end{array}
Initial program 97.7%
associate-+l+97.7%
*-commutative97.7%
associate-*r*97.7%
*-commutative97.7%
associate-/r/98.0%
Simplified98.7%
Taylor expanded in cosTheta around 0 93.6%
Taylor expanded in cosTheta around 0 93.7%
mul-1-neg93.7%
unsub-neg93.7%
*-commutative93.7%
*-commutative93.7%
associate-*l*93.7%
unpow293.7%
+-commutative93.7%
Simplified93.7%
Taylor expanded in c around inf 10.9%
mul-1-neg10.9%
distribute-rgt-neg-in10.9%
*-commutative10.9%
distribute-rgt-neg-in10.9%
unpow210.9%
distribute-rgt-neg-in10.9%
Simplified10.9%
Final simplification10.9%
(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 97.7%
associate-+l+97.7%
*-commutative97.7%
associate-*r*97.7%
*-commutative97.7%
associate-/r/98.0%
Simplified98.7%
Taylor expanded in cosTheta around inf 10.7%
Taylor expanded in c around 0 10.7%
+-commutative10.7%
mul-1-neg10.7%
unsub-neg10.7%
Simplified10.7%
Final simplification10.7%
(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 97.7%
Taylor expanded in c around 0 97.7%
Taylor expanded in cosTheta around inf 10.7%
Final simplification10.7%
herbie shell --seed 2023228
(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))))))