
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (sin (* (* 2.0 PI) u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-logf((1.0f - u1))) * sinf(((2.0f * ((float) M_PI)) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log(Float32(Float32(1.0) - u1)))) * sin(Float32(Float32(Float32(2.0) * Float32(pi)) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(-log((single(1.0) - u1))) * sin(((single(2.0) * single(pi)) * u2)); end
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \sin \left(\left(2 \cdot \pi\right) \cdot u2\right)
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 11 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (sin (* (* 2.0 PI) u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-logf((1.0f - u1))) * sinf(((2.0f * ((float) M_PI)) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log(Float32(Float32(1.0) - u1)))) * sin(Float32(Float32(Float32(2.0) * Float32(pi)) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(-log((single(1.0) - u1))) * sin(((single(2.0) * single(pi)) * u2)); end
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \sin \left(\left(2 \cdot \pi\right) \cdot u2\right)
\end{array}
(FPCore (cosTheta_i u1 u2) :precision binary32 (let* ((t_0 (cbrt (* 2.0 PI)))) (* (sqrt (- (log1p (- u1)))) (sin (* (pow t_0 2.0) (* t_0 u2))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = cbrtf((2.0f * ((float) M_PI)));
return sqrtf(-log1pf(-u1)) * sinf((powf(t_0, 2.0f) * (t_0 * u2)));
}
function code(cosTheta_i, u1, u2) t_0 = cbrt(Float32(Float32(2.0) * Float32(pi))) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * sin(Float32((t_0 ^ Float32(2.0)) * Float32(t_0 * u2)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt[3]{2 \cdot \pi}\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \sin \left({t\_0}^{2} \cdot \left(t\_0 \cdot u2\right)\right)
\end{array}
\end{array}
Initial program 61.0%
sub-neg61.0%
log1p-define98.4%
Simplified98.4%
expm1-log1p-u98.4%
associate-*l*98.4%
Applied egg-rr98.4%
expm1-log1p-u98.4%
associate-*r*98.4%
add-cube-cbrt98.4%
associate-*l*98.6%
pow298.6%
Applied egg-rr98.6%
(FPCore (cosTheta_i u1 u2) :precision binary32 (let* ((t_0 (sqrt (* 2.0 PI)))) (* (sqrt (- (log1p (- u1)))) (sin (* t_0 (* u2 t_0))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = sqrtf((2.0f * ((float) M_PI)));
return sqrtf(-log1pf(-u1)) * sinf((t_0 * (u2 * t_0)));
}
function code(cosTheta_i, u1, u2) t_0 = sqrt(Float32(Float32(2.0) * Float32(pi))) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * sin(Float32(t_0 * Float32(u2 * t_0)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sqrt{2 \cdot \pi}\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \sin \left(t\_0 \cdot \left(u2 \cdot t\_0\right)\right)
\end{array}
\end{array}
Initial program 61.0%
sub-neg61.0%
log1p-define98.4%
Simplified98.4%
expm1-log1p-u98.4%
associate-*l*98.4%
Applied egg-rr98.4%
expm1-log1p-u98.4%
associate-*r*98.4%
add-sqr-sqrt98.4%
associate-*l*98.5%
Applied egg-rr98.5%
Final simplification98.5%
(FPCore (cosTheta_i u1 u2) :precision binary32 (cbrt (* (pow (sin (* (* 2.0 PI) u2)) 3.0) (pow (- (log1p (- u1))) 1.5))))
float code(float cosTheta_i, float u1, float u2) {
return cbrtf((powf(sinf(((2.0f * ((float) M_PI)) * u2)), 3.0f) * powf(-log1pf(-u1), 1.5f)));
}
function code(cosTheta_i, u1, u2) return cbrt(Float32((sin(Float32(Float32(Float32(2.0) * Float32(pi)) * u2)) ^ Float32(3.0)) * (Float32(-log1p(Float32(-u1))) ^ Float32(1.5)))) end
\begin{array}{l}
\\
\sqrt[3]{{\sin \left(\left(2 \cdot \pi\right) \cdot u2\right)}^{3} \cdot {\left(-\mathsf{log1p}\left(-u1\right)\right)}^{1.5}}
\end{array}
Initial program 61.0%
sub-neg61.0%
log1p-define98.4%
Simplified98.4%
expm1-log1p-u98.4%
associate-*l*98.4%
Applied egg-rr98.4%
expm1-log1p-u98.4%
associate-*r*98.4%
add-cube-cbrt98.4%
associate-*l*98.6%
pow298.6%
Applied egg-rr98.6%
*-commutative98.6%
add-cbrt-cube98.6%
add-cbrt-cube98.5%
cbrt-unprod98.3%
Applied egg-rr98.4%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log1p (- u1)))) (sin (* (* 2.0 PI) u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-log1pf(-u1)) * sinf(((2.0f * ((float) M_PI)) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * sin(Float32(Float32(Float32(2.0) * Float32(pi)) * u2))) end
\begin{array}{l}
\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \sin \left(\left(2 \cdot \pi\right) \cdot u2\right)
\end{array}
Initial program 61.0%
sub-neg61.0%
log1p-define98.4%
Simplified98.4%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* (* 2.0 PI) u2)))
(if (<= t_0 0.0011500000255182385)
(* (sqrt (- (log1p (- u1)))) (* 2.0 (* PI u2)))
(*
(sin t_0)
(sqrt
(*
u1
(+ 1.0 (* u1 (+ 0.5 (* u1 (- 0.3333333333333333 (* u1 -0.25))))))))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = (2.0f * ((float) M_PI)) * u2;
float tmp;
if (t_0 <= 0.0011500000255182385f) {
tmp = sqrtf(-log1pf(-u1)) * (2.0f * (((float) M_PI) * u2));
} else {
tmp = sinf(t_0) * sqrtf((u1 * (1.0f + (u1 * (0.5f + (u1 * (0.3333333333333333f - (u1 * -0.25f))))))));
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = Float32(Float32(Float32(2.0) * Float32(pi)) * u2) tmp = Float32(0.0) if (t_0 <= Float32(0.0011500000255182385)) tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * Float32(Float32(2.0) * Float32(Float32(pi) * u2))); else tmp = Float32(sin(t_0) * sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(Float32(0.5) + Float32(u1 * Float32(Float32(0.3333333333333333) - Float32(u1 * Float32(-0.25)))))))))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(2 \cdot \pi\right) \cdot u2\\
\mathbf{if}\;t\_0 \leq 0.0011500000255182385:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \left(2 \cdot \left(\pi \cdot u2\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\sin t\_0 \cdot \sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 + u1 \cdot \left(0.3333333333333333 - u1 \cdot -0.25\right)\right)\right)}\\
\end{array}
\end{array}
if (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) < 0.00115000003Initial program 63.5%
sub-neg63.5%
log1p-define98.4%
Simplified98.4%
Taylor expanded in u2 around 0 98.4%
Taylor expanded in u2 around 0 98.2%
if 0.00115000003 < (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) Initial program 56.8%
Taylor expanded in u1 around 0 93.8%
Final simplification96.5%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* (* 2.0 PI) u2)))
(if (<= t_0 0.0011500000255182385)
(* (sqrt (- (log1p (- u1)))) (* 2.0 (* PI u2)))
(*
(sin t_0)
(sqrt (* u1 (+ 1.0 (* u1 (- 0.5 (* u1 -0.3333333333333333))))))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = (2.0f * ((float) M_PI)) * u2;
float tmp;
if (t_0 <= 0.0011500000255182385f) {
tmp = sqrtf(-log1pf(-u1)) * (2.0f * (((float) M_PI) * u2));
} else {
tmp = sinf(t_0) * sqrtf((u1 * (1.0f + (u1 * (0.5f - (u1 * -0.3333333333333333f))))));
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = Float32(Float32(Float32(2.0) * Float32(pi)) * u2) tmp = Float32(0.0) if (t_0 <= Float32(0.0011500000255182385)) tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * Float32(Float32(2.0) * Float32(Float32(pi) * u2))); else tmp = Float32(sin(t_0) * sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(Float32(0.5) - Float32(u1 * Float32(-0.3333333333333333)))))))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(2 \cdot \pi\right) \cdot u2\\
\mathbf{if}\;t\_0 \leq 0.0011500000255182385:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \left(2 \cdot \left(\pi \cdot u2\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\sin t\_0 \cdot \sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 - u1 \cdot -0.3333333333333333\right)\right)}\\
\end{array}
\end{array}
if (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) < 0.00115000003Initial program 63.5%
sub-neg63.5%
log1p-define98.4%
Simplified98.4%
Taylor expanded in u2 around 0 98.4%
Taylor expanded in u2 around 0 98.2%
if 0.00115000003 < (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) Initial program 56.8%
Taylor expanded in u1 around 0 92.5%
Final simplification96.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (if (<= u1 0.003594999900087714) (* (sin (* (* 2.0 PI) u2)) (sqrt (* u1 (- 1.0 (* u1 -0.5))))) (* (sqrt (- (log1p (- u1)))) (* 2.0 (* PI u2)))))
float code(float cosTheta_i, float u1, float u2) {
float tmp;
if (u1 <= 0.003594999900087714f) {
tmp = sinf(((2.0f * ((float) M_PI)) * u2)) * sqrtf((u1 * (1.0f - (u1 * -0.5f))));
} else {
tmp = sqrtf(-log1pf(-u1)) * (2.0f * (((float) M_PI) * u2));
}
return tmp;
}
function code(cosTheta_i, u1, u2) tmp = Float32(0.0) if (u1 <= Float32(0.003594999900087714)) tmp = Float32(sin(Float32(Float32(Float32(2.0) * Float32(pi)) * u2)) * sqrt(Float32(u1 * Float32(Float32(1.0) - Float32(u1 * Float32(-0.5)))))); else tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * Float32(Float32(2.0) * Float32(Float32(pi) * u2))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;u1 \leq 0.003594999900087714:\\
\;\;\;\;\sin \left(\left(2 \cdot \pi\right) \cdot u2\right) \cdot \sqrt{u1 \cdot \left(1 - u1 \cdot -0.5\right)}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \left(2 \cdot \left(\pi \cdot u2\right)\right)\\
\end{array}
\end{array}
if u1 < 0.0035949999Initial program 48.3%
Taylor expanded in u1 around 0 97.5%
if 0.0035949999 < u1 Initial program 94.7%
sub-neg94.7%
log1p-define98.7%
Simplified98.7%
Taylor expanded in u2 around 0 93.0%
Taylor expanded in u2 around 0 87.2%
Final simplification94.7%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* (* 2.0 PI) u2)))
(if (<= t_0 0.007499999832361937)
(* (sqrt (- (log1p (- u1)))) (* 2.0 (* PI u2)))
(* (sin t_0) (sqrt u1)))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = (2.0f * ((float) M_PI)) * u2;
float tmp;
if (t_0 <= 0.007499999832361937f) {
tmp = sqrtf(-log1pf(-u1)) * (2.0f * (((float) M_PI) * u2));
} else {
tmp = sinf(t_0) * sqrtf(u1);
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = Float32(Float32(Float32(2.0) * Float32(pi)) * u2) tmp = Float32(0.0) if (t_0 <= Float32(0.007499999832361937)) tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * Float32(Float32(2.0) * Float32(Float32(pi) * u2))); else tmp = Float32(sin(t_0) * sqrt(u1)); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \left(2 \cdot \pi\right) \cdot u2\\
\mathbf{if}\;t\_0 \leq 0.007499999832361937:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \left(2 \cdot \left(\pi \cdot u2\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\sin t\_0 \cdot \sqrt{u1}\\
\end{array}
\end{array}
if (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) < 0.00749999983Initial program 62.9%
sub-neg62.9%
log1p-define98.4%
Simplified98.4%
Taylor expanded in u2 around 0 98.4%
Taylor expanded in u2 around 0 96.8%
if 0.00749999983 < (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) Initial program 56.5%
add-exp-log54.2%
add-sqr-sqrt54.2%
sqrt-unprod54.2%
sqr-neg54.2%
sqrt-unprod1.6%
add-sqr-sqrt1.6%
sub-neg1.6%
log1p-undefine-0.0%
add-sqr-sqrt-0.0%
sqrt-unprod69.8%
sqr-neg69.8%
sqrt-unprod69.7%
add-sqr-sqrt69.8%
associate-*l*69.8%
Applied egg-rr69.8%
Taylor expanded in u1 around 0 77.6%
*-commutative77.6%
associate-*r*77.6%
*-commutative77.6%
Simplified77.6%
Final simplification91.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sin (* (* 2.0 PI) u2)) (sqrt u1)))
float code(float cosTheta_i, float u1, float u2) {
return sinf(((2.0f * ((float) M_PI)) * u2)) * sqrtf(u1);
}
function code(cosTheta_i, u1, u2) return Float32(sin(Float32(Float32(Float32(2.0) * Float32(pi)) * u2)) * sqrt(u1)) end
function tmp = code(cosTheta_i, u1, u2) tmp = sin(((single(2.0) * single(pi)) * u2)) * sqrt(u1); end
\begin{array}{l}
\\
\sin \left(\left(2 \cdot \pi\right) \cdot u2\right) \cdot \sqrt{u1}
\end{array}
Initial program 61.0%
add-exp-log59.9%
add-sqr-sqrt59.9%
sqrt-unprod59.9%
sqr-neg59.9%
sqrt-unprod1.4%
add-sqr-sqrt1.4%
sub-neg1.4%
log1p-undefine-0.0%
add-sqr-sqrt-0.0%
sqrt-unprod69.4%
sqr-neg69.4%
sqrt-unprod69.3%
add-sqr-sqrt69.4%
associate-*l*69.4%
Applied egg-rr69.4%
Taylor expanded in u1 around 0 74.4%
*-commutative74.4%
associate-*r*74.4%
*-commutative74.4%
Simplified74.4%
Final simplification74.4%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* 2.0 (* (* PI u2) (sqrt u1))))
float code(float cosTheta_i, float u1, float u2) {
return 2.0f * ((((float) M_PI) * u2) * sqrtf(u1));
}
function code(cosTheta_i, u1, u2) return Float32(Float32(2.0) * Float32(Float32(Float32(pi) * u2) * sqrt(u1))) end
function tmp = code(cosTheta_i, u1, u2) tmp = single(2.0) * ((single(pi) * u2) * sqrt(u1)); end
\begin{array}{l}
\\
2 \cdot \left(\left(\pi \cdot u2\right) \cdot \sqrt{u1}\right)
\end{array}
Initial program 61.0%
add-exp-log59.9%
add-sqr-sqrt59.9%
sqrt-unprod59.9%
sqr-neg59.9%
sqrt-unprod1.4%
add-sqr-sqrt1.4%
sub-neg1.4%
log1p-undefine-0.0%
add-sqr-sqrt-0.0%
sqrt-unprod69.4%
sqr-neg69.4%
sqrt-unprod69.3%
add-sqr-sqrt69.4%
associate-*l*69.4%
Applied egg-rr69.4%
Taylor expanded in u2 around 0 39.1%
associate-*l*39.1%
log1p-define63.4%
Simplified63.4%
Taylor expanded in u1 around 0 65.0%
*-commutative65.0%
Simplified65.0%
Final simplification65.0%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* 2.0 (* u2 (* PI (sqrt u1)))))
float code(float cosTheta_i, float u1, float u2) {
return 2.0f * (u2 * (((float) M_PI) * sqrtf(u1)));
}
function code(cosTheta_i, u1, u2) return Float32(Float32(2.0) * Float32(u2 * Float32(Float32(pi) * sqrt(u1)))) end
function tmp = code(cosTheta_i, u1, u2) tmp = single(2.0) * (u2 * (single(pi) * sqrt(u1))); end
\begin{array}{l}
\\
2 \cdot \left(u2 \cdot \left(\pi \cdot \sqrt{u1}\right)\right)
\end{array}
Initial program 61.0%
add-exp-log59.9%
add-sqr-sqrt59.9%
sqrt-unprod59.9%
sqr-neg59.9%
sqrt-unprod1.4%
add-sqr-sqrt1.4%
sub-neg1.4%
log1p-undefine-0.0%
add-sqr-sqrt-0.0%
sqrt-unprod69.4%
sqr-neg69.4%
sqrt-unprod69.3%
add-sqr-sqrt69.4%
associate-*l*69.4%
Applied egg-rr69.4%
Taylor expanded in u2 around 0 39.1%
associate-*l*39.1%
log1p-define63.4%
Simplified63.4%
Taylor expanded in u1 around 0 65.0%
Final simplification65.0%
herbie shell --seed 2024092
(FPCore (cosTheta_i u1 u2)
:name "Beckmann Sample, near normal, slope_y"
:precision binary32
:pre (and (and (and (> cosTheta_i 0.9999) (<= cosTheta_i 1.0)) (and (<= 2.328306437e-10 u1) (<= u1 1.0))) (and (<= 2.328306437e-10 u2) (<= u2 1.0)))
(* (sqrt (- (log (- 1.0 u1)))) (sin (* (* 2.0 PI) u2))))