
(FPCore (ux uy maxCos) :precision binary32 (let* ((t_0 (+ (- 1.0 ux) (* ux maxCos)))) (* (sin (* (* 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 sinf(((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(sin(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 = sin(((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\\
\sin \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 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (ux uy maxCos) :precision binary32 (let* ((t_0 (+ (- 1.0 ux) (* ux maxCos)))) (* (sin (* (* 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 sinf(((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(sin(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 = sin(((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\\
\sin \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 (* (cbrt (pow (* ux (- (fma maxCos -2.0 2.0) (* ux (pow (+ maxCos -1.0) 2.0)))) 1.5)) (sin (* PI (* 2.0 uy)))))
float code(float ux, float uy, float maxCos) {
return cbrtf(powf((ux * (fmaf(maxCos, -2.0f, 2.0f) - (ux * powf((maxCos + -1.0f), 2.0f)))), 1.5f)) * sinf((((float) M_PI) * (2.0f * uy)));
}
function code(ux, uy, maxCos) return Float32(cbrt((Float32(ux * Float32(fma(maxCos, Float32(-2.0), Float32(2.0)) - Float32(ux * (Float32(maxCos + Float32(-1.0)) ^ Float32(2.0))))) ^ Float32(1.5))) * sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy)))) end
\begin{array}{l}
\\
\sqrt[3]{{\left(ux \cdot \left(\mathsf{fma}\left(maxCos, -2, 2\right) - ux \cdot {\left(maxCos + -1\right)}^{2}\right)\right)}^{1.5}} \cdot \sin \left(\pi \cdot \left(2 \cdot uy\right)\right)
\end{array}
Initial program 59.2%
Taylor expanded in ux around 0 98.2%
Taylor expanded in uy around inf 98.2%
Simplified98.2%
add-cbrt-cube98.2%
pow1/396.2%
Applied egg-rr96.2%
unpow1/398.3%
Simplified98.3%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* PI (* 2.0 uy))) (sqrt (* ux (+ (* maxCos -2.0) (- 2.0 (* ux (pow (+ maxCos -1.0) 2.0))))))))
float code(float ux, float uy, float maxCos) {
return sinf((((float) M_PI) * (2.0f * uy))) * sqrtf((ux * ((maxCos * -2.0f) + (2.0f - (ux * powf((maxCos + -1.0f), 2.0f))))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy))) * sqrt(Float32(ux * Float32(Float32(maxCos * Float32(-2.0)) + Float32(Float32(2.0) - Float32(ux * (Float32(maxCos + Float32(-1.0)) ^ Float32(2.0)))))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((single(pi) * (single(2.0) * uy))) * sqrt((ux * ((maxCos * single(-2.0)) + (single(2.0) - (ux * ((maxCos + single(-1.0)) ^ single(2.0))))))); end
\begin{array}{l}
\\
\sin \left(\pi \cdot \left(2 \cdot uy\right)\right) \cdot \sqrt{ux \cdot \left(maxCos \cdot -2 + \left(2 - ux \cdot {\left(maxCos + -1\right)}^{2}\right)\right)}
\end{array}
Initial program 59.2%
Taylor expanded in ux around 0 98.2%
Taylor expanded in uy around inf 98.2%
Simplified98.2%
Final simplification98.2%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* PI (* 2.0 uy))) (sqrt (- (* ux (- 2.0 ux)) (* maxCos (* ux (- 2.0 (* ux 2.0))))))))
float code(float ux, float uy, float maxCos) {
return sinf((((float) M_PI) * (2.0f * uy))) * sqrtf(((ux * (2.0f - ux)) - (maxCos * (ux * (2.0f - (ux * 2.0f))))));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy))) * sqrt(Float32(Float32(ux * Float32(Float32(2.0) - ux)) - Float32(maxCos * Float32(ux * Float32(Float32(2.0) - Float32(ux * Float32(2.0)))))))) end
function tmp = code(ux, uy, maxCos) tmp = sin((single(pi) * (single(2.0) * uy))) * sqrt(((ux * (single(2.0) - ux)) - (maxCos * (ux * (single(2.0) - (ux * single(2.0))))))); end
\begin{array}{l}
\\
\sin \left(\pi \cdot \left(2 \cdot uy\right)\right) \cdot \sqrt{ux \cdot \left(2 - ux\right) - maxCos \cdot \left(ux \cdot \left(2 - ux \cdot 2\right)\right)}
\end{array}
Initial program 59.2%
Taylor expanded in ux around 0 98.2%
Taylor expanded in uy around inf 98.2%
Simplified98.2%
Taylor expanded in maxCos around 0 97.5%
+-commutative97.5%
mul-1-neg97.5%
unsub-neg97.5%
metadata-eval97.5%
cancel-sign-sub-inv97.5%
*-commutative97.5%
Simplified97.5%
Final simplification97.5%
(FPCore (ux uy maxCos) :precision binary32 (* (sin (* PI (* 2.0 uy))) (sqrt (* ux (- 2.0 ux)))))
float code(float ux, float uy, float maxCos) {
return sinf((((float) M_PI) * (2.0f * uy))) * sqrtf((ux * (2.0f - ux)));
}
function code(ux, uy, maxCos) return Float32(sin(Float32(Float32(pi) * Float32(Float32(2.0) * uy))) * sqrt(Float32(ux * Float32(Float32(2.0) - ux)))) end
function tmp = code(ux, uy, maxCos) tmp = sin((single(pi) * (single(2.0) * uy))) * sqrt((ux * (single(2.0) - ux))); end
\begin{array}{l}
\\
\sin \left(\pi \cdot \left(2 \cdot uy\right)\right) \cdot \sqrt{ux \cdot \left(2 - ux\right)}
\end{array}
Initial program 59.2%
Taylor expanded in ux around 0 98.2%
Taylor expanded in maxCos around 0 90.8%
neg-mul-190.8%
unsub-neg90.8%
Simplified90.8%
Final simplification90.8%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (sqrt (- (* ux (- 2.0 ux)) (* maxCos (* ux (- 2.0 (* ux 2.0)))))) (* PI uy))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (sqrtf(((ux * (2.0f - ux)) - (maxCos * (ux * (2.0f - (ux * 2.0f)))))) * (((float) M_PI) * uy));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(sqrt(Float32(Float32(ux * Float32(Float32(2.0) - ux)) - Float32(maxCos * Float32(ux * Float32(Float32(2.0) - Float32(ux * Float32(2.0))))))) * Float32(Float32(pi) * uy))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (sqrt(((ux * (single(2.0) - ux)) - (maxCos * (ux * (single(2.0) - (ux * single(2.0))))))) * (single(pi) * uy)); end
\begin{array}{l}
\\
2 \cdot \left(\sqrt{ux \cdot \left(2 - ux\right) - maxCos \cdot \left(ux \cdot \left(2 - ux \cdot 2\right)\right)} \cdot \left(\pi \cdot uy\right)\right)
\end{array}
Initial program 59.2%
Taylor expanded in ux around 0 98.2%
Taylor expanded in uy around 0 82.3%
Simplified82.3%
Taylor expanded in maxCos around 0 82.0%
+-commutative97.5%
mul-1-neg97.5%
unsub-neg97.5%
metadata-eval97.5%
cancel-sign-sub-inv97.5%
*-commutative97.5%
Simplified82.0%
Final simplification82.0%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (sqrt (* ux (- 2.0 ux))) (* PI uy))))
float code(float ux, float uy, float maxCos) {
return 2.0f * (sqrtf((ux * (2.0f - ux))) * (((float) M_PI) * uy));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(sqrt(Float32(ux * Float32(Float32(2.0) - ux))) * Float32(Float32(pi) * uy))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * (sqrt((ux * (single(2.0) - ux))) * (single(pi) * uy)); end
\begin{array}{l}
\\
2 \cdot \left(\sqrt{ux \cdot \left(2 - ux\right)} \cdot \left(\pi \cdot uy\right)\right)
\end{array}
Initial program 59.2%
Taylor expanded in ux around 0 98.2%
Taylor expanded in uy around 0 82.3%
Simplified82.3%
Taylor expanded in maxCos around 0 77.2%
*-commutative77.2%
Simplified77.2%
Final simplification77.2%
(FPCore (ux uy maxCos) :precision binary32 (* 2.0 (* (* PI uy) (sqrt (* ux 2.0)))))
float code(float ux, float uy, float maxCos) {
return 2.0f * ((((float) M_PI) * uy) * sqrtf((ux * 2.0f)));
}
function code(ux, uy, maxCos) return Float32(Float32(2.0) * Float32(Float32(Float32(pi) * uy) * sqrt(Float32(ux * Float32(2.0))))) end
function tmp = code(ux, uy, maxCos) tmp = single(2.0) * ((single(pi) * uy) * sqrt((ux * single(2.0)))); end
\begin{array}{l}
\\
2 \cdot \left(\left(\pi \cdot uy\right) \cdot \sqrt{ux \cdot 2}\right)
\end{array}
Initial program 59.2%
Taylor expanded in ux around 0 98.2%
Taylor expanded in uy around 0 82.3%
Simplified82.3%
Taylor expanded in maxCos around 0 77.2%
*-commutative77.2%
Simplified77.2%
Taylor expanded in ux around 0 63.2%
*-commutative63.2%
Simplified63.2%
Final simplification63.2%
herbie shell --seed 2024096
(FPCore (ux uy maxCos)
:name "UniformSampleCone, y"
: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)))
(* (sin (* (* uy 2.0) PI)) (sqrt (- 1.0 (* (+ (- 1.0 ux) (* ux maxCos)) (+ (- 1.0 ux) (* ux maxCos)))))))