
(FPCore (ux uy maxCos) :precision binary32 (let* ((t_0 (+ (- 1.0 ux) (* ux maxCos)))) (* (cos (* (* uy 2.0) PI)) (sqrt (- 1.0 (* t_0 t_0))))))
float code(float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) + (ux * maxCos);
return cosf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((1.0f - (t_0 * t_0)));
}
function code(ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) + Float32(ux * maxCos)) return Float32(cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0)))) end
function tmp = code(ux, uy, maxCos) t_0 = (single(1.0) - ux) + (ux * maxCos); tmp = cos(((uy * single(2.0)) * single(pi))) * sqrt((single(1.0) - (t_0 * t_0))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) + ux \cdot maxCos\\
\cos \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{1 - t\_0 \cdot t\_0}
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (ux uy maxCos) :precision binary32 (let* ((t_0 (+ (- 1.0 ux) (* ux maxCos)))) (* (cos (* (* uy 2.0) PI)) (sqrt (- 1.0 (* t_0 t_0))))))
float code(float ux, float uy, float maxCos) {
float t_0 = (1.0f - ux) + (ux * maxCos);
return cosf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((1.0f - (t_0 * t_0)));
}
function code(ux, uy, maxCos) t_0 = Float32(Float32(Float32(1.0) - ux) + Float32(ux * maxCos)) return Float32(cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(Float32(1.0) - Float32(t_0 * t_0)))) end
function tmp = code(ux, uy, maxCos) t_0 = (single(1.0) - ux) + (ux * maxCos); tmp = cos(((uy * single(2.0)) * single(pi))) * sqrt((single(1.0) - (t_0 * t_0))); end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(1 - ux\right) + ux \cdot maxCos\\
\cos \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{1 - t\_0 \cdot t\_0}
\end{array}
\end{array}
(FPCore (ux uy maxCos)
:precision binary32
(*
(cos (* (* uy 2.0) PI))
(sqrt
(*
ux
(+
(+ 2.0 (- (* maxCos (- (* 2.0 ux) (* ux maxCos))) ux))
(* maxCos -2.0))))))
float code(float ux, float uy, float maxCos) {
return cosf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((ux * ((2.0f + ((maxCos * ((2.0f * ux) - (ux * maxCos))) - ux)) + (maxCos * -2.0f))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(Float32(2.0) + Float32(Float32(maxCos * Float32(Float32(Float32(2.0) * ux) - Float32(ux * maxCos))) - ux)) + Float32(maxCos * Float32(-2.0)))))) end
function tmp = code(ux, uy, maxCos) tmp = cos(((uy * single(2.0)) * single(pi))) * sqrt((ux * ((single(2.0) + ((maxCos * ((single(2.0) * ux) - (ux * maxCos))) - ux)) + (maxCos * single(-2.0))))); end
\begin{array}{l}
\\
\cos \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(\left(2 + \left(maxCos \cdot \left(2 \cdot ux - ux \cdot maxCos\right) - ux\right)\right) + maxCos \cdot -2\right)}
\end{array}
Initial program 55.5%
Taylor expanded in ux around 0 98.9%
cancel-sign-sub-inv98.9%
associate-*r*98.9%
mul-1-neg98.9%
sub-neg98.9%
metadata-eval98.9%
+-commutative98.9%
metadata-eval98.9%
Simplified98.9%
Taylor expanded in maxCos around 0 98.9%
Final simplification98.9%
(FPCore (ux uy maxCos) :precision binary32 (* (* ux (cos (* 2.0 (* uy PI)))) (sqrt (+ -1.0 (+ (/ 2.0 ux) (* maxCos (- (- 2.0 maxCos) (/ 2.0 ux))))))))
float code(float ux, float uy, float maxCos) {
return (ux * cosf((2.0f * (uy * ((float) M_PI))))) * sqrtf((-1.0f + ((2.0f / ux) + (maxCos * ((2.0f - maxCos) - (2.0f / ux))))));
}
function code(ux, uy, maxCos) return Float32(Float32(ux * cos(Float32(Float32(2.0) * Float32(uy * Float32(pi))))) * sqrt(Float32(Float32(-1.0) + Float32(Float32(Float32(2.0) / ux) + Float32(maxCos * Float32(Float32(Float32(2.0) - maxCos) - Float32(Float32(2.0) / ux))))))) end
function tmp = code(ux, uy, maxCos) tmp = (ux * cos((single(2.0) * (uy * single(pi))))) * sqrt((single(-1.0) + ((single(2.0) / ux) + (maxCos * ((single(2.0) - maxCos) - (single(2.0) / ux)))))); end
\begin{array}{l}
\\
\left(ux \cdot \cos \left(2 \cdot \left(uy \cdot \pi\right)\right)\right) \cdot \sqrt{-1 + \left(\frac{2}{ux} + maxCos \cdot \left(\left(2 - maxCos\right) - \frac{2}{ux}\right)\right)}
\end{array}
Initial program 55.5%
Taylor expanded in ux around -inf 98.5%
Taylor expanded in uy around inf 98.4%
Taylor expanded in maxCos around 0 98.4%
sub-neg98.4%
associate-*r/98.4%
metadata-eval98.4%
neg-mul-198.4%
associate-*r/98.4%
metadata-eval98.4%
metadata-eval98.4%
Simplified98.4%
Final simplification98.4%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* (* uy 2.0) PI)) (sqrt (* ux (+ (* maxCos -2.0) (+ 2.0 (- (* ux (* 2.0 maxCos)) ux)))))))
float code(float ux, float uy, float maxCos) {
return cosf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((ux * ((maxCos * -2.0f) + (2.0f + ((ux * (2.0f * maxCos)) - ux)))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(maxCos * Float32(-2.0)) + Float32(Float32(2.0) + Float32(Float32(ux * Float32(Float32(2.0) * maxCos)) - ux)))))) end
function tmp = code(ux, uy, maxCos) tmp = cos(((uy * single(2.0)) * single(pi))) * sqrt((ux * ((maxCos * single(-2.0)) + (single(2.0) + ((ux * (single(2.0) * maxCos)) - ux))))); end
\begin{array}{l}
\\
\cos \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(maxCos \cdot -2 + \left(2 + \left(ux \cdot \left(2 \cdot maxCos\right) - ux\right)\right)\right)}
\end{array}
Initial program 55.5%
Taylor expanded in ux around 0 98.9%
cancel-sign-sub-inv98.9%
associate-*r*98.9%
mul-1-neg98.9%
sub-neg98.9%
metadata-eval98.9%
+-commutative98.9%
metadata-eval98.9%
Simplified98.9%
Taylor expanded in maxCos around 0 98.9%
Taylor expanded in maxCos around 0 98.2%
neg-mul-198.2%
+-commutative98.2%
unsub-neg98.2%
*-commutative98.2%
associate-*r*98.2%
*-commutative98.2%
associate-*l*98.2%
*-commutative98.2%
Simplified98.2%
Final simplification98.2%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* (* uy 2.0) PI)) (sqrt (* ux (+ (* maxCos -2.0) (- 2.0 ux))))))
float code(float ux, float uy, float maxCos) {
return cosf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((ux * ((maxCos * -2.0f) + (2.0f - ux))));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(maxCos * Float32(-2.0)) + Float32(Float32(2.0) - ux))))) end
function tmp = code(ux, uy, maxCos) tmp = cos(((uy * single(2.0)) * single(pi))) * sqrt((ux * ((maxCos * single(-2.0)) + (single(2.0) - ux)))); end
\begin{array}{l}
\\
\cos \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(maxCos \cdot -2 + \left(2 - ux\right)\right)}
\end{array}
Initial program 55.5%
Taylor expanded in ux around 0 98.9%
cancel-sign-sub-inv98.9%
associate-*r*98.9%
mul-1-neg98.9%
sub-neg98.9%
metadata-eval98.9%
+-commutative98.9%
metadata-eval98.9%
Simplified98.9%
Taylor expanded in maxCos around 0 97.6%
neg-mul-197.6%
Simplified97.6%
Final simplification97.6%
(FPCore (ux uy maxCos) :precision binary32 (* (cos (* (* uy 2.0) PI)) (sqrt (* ux (- 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return cosf(((uy * 2.0f) * ((float) M_PI))) * sqrtf((ux * (2.0f - ux)));
}
function code(ux, uy, maxCos) return Float32(cos(Float32(Float32(uy * Float32(2.0)) * Float32(pi))) * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))) end
function tmp = code(ux, uy, maxCos) tmp = cos(((uy * single(2.0)) * single(pi))) * sqrt((ux * (single(2.0) - ux))); end
\begin{array}{l}
\\
\cos \left(\left(uy \cdot 2\right) \cdot \pi\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 55.5%
Taylor expanded in ux around 0 98.9%
cancel-sign-sub-inv98.9%
associate-*r*98.9%
mul-1-neg98.9%
sub-neg98.9%
metadata-eval98.9%
+-commutative98.9%
metadata-eval98.9%
Simplified98.9%
Taylor expanded in maxCos around 0 98.9%
Taylor expanded in maxCos around 0 94.2%
neg-mul-194.2%
unsub-neg94.2%
Simplified94.2%
(FPCore (ux uy maxCos)
:precision binary32
(sqrt
(*
ux
(+
2.0
(+ (- (* maxCos (- (* 2.0 ux) (* ux maxCos))) ux) (* maxCos -2.0))))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f + (((maxCos * ((2.0f * ux) - (ux * maxCos))) - ux) + (maxCos * -2.0f)))));
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = sqrt((ux * (2.0e0 + (((maxcos * ((2.0e0 * ux) - (ux * maxcos))) - ux) + (maxcos * (-2.0e0))))))
end function
function code(ux, uy, maxCos) return sqrt(Float32(ux * Float32(Float32(2.0) + Float32(Float32(Float32(maxCos * Float32(Float32(Float32(2.0) * ux) - Float32(ux * maxCos))) - ux) + Float32(maxCos * Float32(-2.0)))))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) + (((maxCos * ((single(2.0) * ux) - (ux * maxCos))) - ux) + (maxCos * single(-2.0)))))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 + \left(\left(maxCos \cdot \left(2 \cdot ux - ux \cdot maxCos\right) - ux\right) + maxCos \cdot -2\right)\right)}
\end{array}
Initial program 55.5%
Taylor expanded in ux around 0 98.9%
cancel-sign-sub-inv98.9%
associate-*r*98.9%
mul-1-neg98.9%
sub-neg98.9%
metadata-eval98.9%
+-commutative98.9%
metadata-eval98.9%
Simplified98.9%
Taylor expanded in maxCos around 0 98.9%
Taylor expanded in uy around 0 80.1%
Final simplification80.1%
(FPCore (ux uy maxCos) :precision binary32 (* ux (sqrt (+ -1.0 (/ 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return ux * sqrtf((-1.0f + (2.0f / ux)));
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = ux * sqrt(((-1.0e0) + (2.0e0 / ux)))
end function
function code(ux, uy, maxCos) return Float32(ux * sqrt(Float32(Float32(-1.0) + Float32(Float32(2.0) / ux)))) end
function tmp = code(ux, uy, maxCos) tmp = ux * sqrt((single(-1.0) + (single(2.0) / ux))); end
\begin{array}{l}
\\
ux \cdot \sqrt{-1 + \frac{2}{ux}}
\end{array}
Initial program 55.5%
Taylor expanded in ux around -inf 98.5%
Taylor expanded in maxCos around 0 93.7%
sub-neg93.7%
associate-*r/93.7%
metadata-eval93.7%
metadata-eval93.7%
Simplified93.7%
Taylor expanded in uy around 0 76.5%
sub-neg76.5%
metadata-eval76.5%
+-commutative76.5%
associate-*r/76.5%
metadata-eval76.5%
Simplified76.5%
(FPCore (ux uy maxCos) :precision binary32 (sqrt (* ux (- 2.0 (* 2.0 maxCos)))))
float code(float ux, float uy, float maxCos) {
return sqrtf((ux * (2.0f - (2.0f * maxCos))));
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = sqrt((ux * (2.0e0 - (2.0e0 * maxcos))))
end function
function code(ux, uy, maxCos) return sqrt(Float32(ux * Float32(Float32(2.0) - Float32(Float32(2.0) * maxCos)))) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((ux * (single(2.0) - (single(2.0) * maxCos)))); end
\begin{array}{l}
\\
\sqrt{ux \cdot \left(2 - 2 \cdot maxCos\right)}
\end{array}
Initial program 55.5%
associate-*l*55.5%
sub-neg55.5%
+-commutative55.5%
distribute-rgt-neg-in55.5%
fma-define55.6%
Simplified55.7%
Taylor expanded in uy around 0 48.4%
Simplified48.4%
Taylor expanded in ux around 0 65.1%
(FPCore (ux uy maxCos) :precision binary32 (sqrt (* 2.0 ux)))
float code(float ux, float uy, float maxCos) {
return sqrtf((2.0f * ux));
}
real(4) function code(ux, uy, maxcos)
real(4), intent (in) :: ux
real(4), intent (in) :: uy
real(4), intent (in) :: maxcos
code = sqrt((2.0e0 * ux))
end function
function code(ux, uy, maxCos) return sqrt(Float32(Float32(2.0) * ux)) end
function tmp = code(ux, uy, maxCos) tmp = sqrt((single(2.0) * ux)); end
\begin{array}{l}
\\
\sqrt{2 \cdot ux}
\end{array}
Initial program 55.5%
associate-*l*55.5%
sub-neg55.5%
+-commutative55.5%
distribute-rgt-neg-in55.5%
fma-define55.6%
Simplified55.7%
Taylor expanded in uy around 0 48.4%
Simplified48.4%
Taylor expanded in ux around 0 65.1%
Taylor expanded in maxCos around 0 62.9%
Final simplification62.9%
herbie shell --seed 2024165
(FPCore (ux uy maxCos)
:name "UniformSampleCone, x"
:precision binary32
:pre (and (and (and (<= 2.328306437e-10 ux) (<= ux 1.0)) (and (<= 2.328306437e-10 uy) (<= uy 1.0))) (and (<= 0.0 maxCos) (<= maxCos 1.0)))
(* (cos (* (* uy 2.0) PI)) (sqrt (- 1.0 (* (+ (- 1.0 ux) (* ux maxCos)) (+ (- 1.0 ux) (* ux maxCos)))))))