
(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 (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 56.5%
sub-neg56.5%
log1p-define98.4%
Simplified98.4%
add-cbrt-cube98.4%
add-cbrt-cube98.4%
cbrt-unprod98.3%
pow398.3%
pow398.4%
Applied egg-rr98.4%
cbrt-prod98.3%
rem-cbrt-cube98.3%
rem-cbrt-cube98.4%
*-commutative98.4%
add-sqr-sqrt98.4%
associate-*r*98.4%
Applied egg-rr98.4%
Final simplification98.4%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log1p (- u1)))) (sin (* u2 (* 2.0 PI)))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-log1pf(-u1)) * sinf((u2 * (2.0f * ((float) M_PI))));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * sin(Float32(u2 * Float32(Float32(2.0) * Float32(pi))))) end
\begin{array}{l}
\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \sin \left(u2 \cdot \left(2 \cdot \pi\right)\right)
\end{array}
Initial program 56.5%
sub-neg56.5%
log1p-define98.4%
Simplified98.4%
Final simplification98.4%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* u2 (* 2.0 PI))))
(if (<= u1 0.07999999821186066)
(*
(sin t_0)
(sqrt
(*
u1
(+ 1.0 (* u1 (+ 0.5 (* u1 (+ 0.3333333333333333 (* u1 0.25)))))))))
(* (sqrt (- (log1p (- u1)))) t_0))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = u2 * (2.0f * ((float) M_PI));
float tmp;
if (u1 <= 0.07999999821186066f) {
tmp = sinf(t_0) * sqrtf((u1 * (1.0f + (u1 * (0.5f + (u1 * (0.3333333333333333f + (u1 * 0.25f))))))));
} else {
tmp = sqrtf(-log1pf(-u1)) * t_0;
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = Float32(u2 * Float32(Float32(2.0) * Float32(pi))) tmp = Float32(0.0) if (u1 <= Float32(0.07999999821186066)) 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)))))))))); else tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * t_0); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := u2 \cdot \left(2 \cdot \pi\right)\\
\mathbf{if}\;u1 \leq 0.07999999821186066:\\
\;\;\;\;\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)}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot t\_0\\
\end{array}
\end{array}
if u1 < 0.0799999982Initial program 52.2%
Taylor expanded in u1 around 0 97.9%
*-commutative97.9%
Simplified97.9%
if 0.0799999982 < u1 Initial program 98.2%
sub-neg98.2%
log1p-define98.6%
Simplified98.6%
add-cbrt-cube98.6%
add-cbrt-cube98.6%
cbrt-unprod98.4%
pow398.4%
pow398.6%
Applied egg-rr98.6%
Taylor expanded in u2 around 0 95.1%
*-commutative95.1%
associate-*r*95.1%
*-commutative95.1%
Simplified95.1%
Final simplification97.7%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* u2 (* 2.0 PI))))
(if (<= t_0 0.0015899999998509884)
(* (sqrt (- (log1p (- u1)))) t_0)
(*
(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 = u2 * (2.0f * ((float) M_PI));
float tmp;
if (t_0 <= 0.0015899999998509884f) {
tmp = sqrtf(-log1pf(-u1)) * t_0;
} 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(u2 * Float32(Float32(2.0) * Float32(pi))) tmp = Float32(0.0) if (t_0 <= Float32(0.0015899999998509884)) tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * t_0); 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 := u2 \cdot \left(2 \cdot \pi\right)\\
\mathbf{if}\;t\_0 \leq 0.0015899999998509884:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot t\_0\\
\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) < 0.00159Initial program 58.7%
sub-neg58.7%
log1p-define98.6%
Simplified98.6%
add-cbrt-cube98.6%
add-cbrt-cube98.6%
cbrt-unprod98.5%
pow398.5%
pow398.6%
Applied egg-rr98.6%
Taylor expanded in u2 around 0 98.5%
*-commutative98.5%
associate-*r*98.5%
*-commutative98.5%
Simplified98.5%
if 0.00159 < (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) Initial program 52.4%
Taylor expanded in u1 around 0 94.7%
*-commutative94.7%
Simplified94.7%
Final simplification97.1%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* u2 (* 2.0 PI))))
(if (<= t_0 0.0015899999998509884)
(* (sqrt (- (log1p (- u1)))) t_0)
(* (sin t_0) (sqrt (* u1 (+ 1.0 (* u1 0.5))))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = u2 * (2.0f * ((float) M_PI));
float tmp;
if (t_0 <= 0.0015899999998509884f) {
tmp = sqrtf(-log1pf(-u1)) * t_0;
} else {
tmp = sinf(t_0) * sqrtf((u1 * (1.0f + (u1 * 0.5f))));
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = Float32(u2 * Float32(Float32(2.0) * Float32(pi))) tmp = Float32(0.0) if (t_0 <= Float32(0.0015899999998509884)) tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * t_0); else tmp = Float32(sin(t_0) * sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(0.5)))))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := u2 \cdot \left(2 \cdot \pi\right)\\
\mathbf{if}\;t\_0 \leq 0.0015899999998509884:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot t\_0\\
\mathbf{else}:\\
\;\;\;\;\sin t\_0 \cdot \sqrt{u1 \cdot \left(1 + u1 \cdot 0.5\right)}\\
\end{array}
\end{array}
if (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) < 0.00159Initial program 58.7%
sub-neg58.7%
log1p-define98.6%
Simplified98.6%
add-cbrt-cube98.6%
add-cbrt-cube98.6%
cbrt-unprod98.5%
pow398.5%
pow398.6%
Applied egg-rr98.6%
Taylor expanded in u2 around 0 98.5%
*-commutative98.5%
associate-*r*98.5%
*-commutative98.5%
Simplified98.5%
if 0.00159 < (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) Initial program 52.4%
Taylor expanded in u1 around 0 91.4%
*-commutative91.4%
Simplified91.4%
Final simplification96.0%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (* u2 (* 2.0 PI))))
(if (<= t_0 0.004900000058114529)
(* (sqrt (- (log1p (- u1)))) t_0)
(* (sin t_0) (pow u1 0.5)))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = u2 * (2.0f * ((float) M_PI));
float tmp;
if (t_0 <= 0.004900000058114529f) {
tmp = sqrtf(-log1pf(-u1)) * t_0;
} else {
tmp = sinf(t_0) * powf(u1, 0.5f);
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = Float32(u2 * Float32(Float32(2.0) * Float32(pi))) tmp = Float32(0.0) if (t_0 <= Float32(0.004900000058114529)) tmp = Float32(sqrt(Float32(-log1p(Float32(-u1)))) * t_0); else tmp = Float32(sin(t_0) * (u1 ^ Float32(0.5))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := u2 \cdot \left(2 \cdot \pi\right)\\
\mathbf{if}\;t\_0 \leq 0.004900000058114529:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot t\_0\\
\mathbf{else}:\\
\;\;\;\;\sin t\_0 \cdot {u1}^{0.5}\\
\end{array}
\end{array}
if (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) < 0.00490000006Initial program 58.4%
sub-neg58.4%
log1p-define98.6%
Simplified98.6%
add-cbrt-cube98.6%
add-cbrt-cube98.6%
cbrt-unprod98.5%
pow398.5%
pow398.6%
Applied egg-rr98.6%
Taylor expanded in u2 around 0 97.7%
*-commutative97.7%
associate-*r*97.7%
*-commutative97.7%
Simplified97.7%
if 0.00490000006 < (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) Initial program 52.4%
Taylor expanded in u1 around 0 79.4%
pow1/279.4%
Applied egg-rr79.4%
Final simplification92.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sin (* u2 (* 2.0 PI))) (pow u1 0.5)))
float code(float cosTheta_i, float u1, float u2) {
return sinf((u2 * (2.0f * ((float) M_PI)))) * powf(u1, 0.5f);
}
function code(cosTheta_i, u1, u2) return Float32(sin(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) * (u1 ^ Float32(0.5))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sin((u2 * (single(2.0) * single(pi)))) * (u1 ^ single(0.5)); end
\begin{array}{l}
\\
\sin \left(u2 \cdot \left(2 \cdot \pi\right)\right) \cdot {u1}^{0.5}
\end{array}
Initial program 56.5%
Taylor expanded in u1 around 0 77.5%
pow1/277.5%
Applied egg-rr77.5%
Final simplification77.5%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sin (* u2 (* 2.0 PI))) (sqrt u1)))
float code(float cosTheta_i, float u1, float u2) {
return sinf((u2 * (2.0f * ((float) M_PI)))) * sqrtf(u1);
}
function code(cosTheta_i, u1, u2) return Float32(sin(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) * sqrt(u1)) end
function tmp = code(cosTheta_i, u1, u2) tmp = sin((u2 * (single(2.0) * single(pi)))) * sqrt(u1); end
\begin{array}{l}
\\
\sin \left(u2 \cdot \left(2 \cdot \pi\right)\right) \cdot \sqrt{u1}
\end{array}
Initial program 56.5%
Taylor expanded in u1 around 0 77.5%
Final simplification77.5%
(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(pi) * Float32(u2 * Float32(-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(\pi \cdot \left(u2 \cdot \left(-\sqrt{u1}\right)\right)\right)
\end{array}
Initial program 56.5%
Taylor expanded in u1 around 0 77.5%
Taylor expanded in u2 around 0 66.9%
Taylor expanded in u1 around -inf -0.0%
associate-*r*-0.0%
unpow2-0.0%
rem-square-sqrt66.9%
Simplified66.9%
Final simplification66.9%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* 2.0 (* (pow u1 0.5) (* u2 PI))))
float code(float cosTheta_i, float u1, float u2) {
return 2.0f * (powf(u1, 0.5f) * (u2 * ((float) M_PI)));
}
function code(cosTheta_i, u1, u2) return Float32(Float32(2.0) * Float32((u1 ^ Float32(0.5)) * Float32(u2 * Float32(pi)))) end
function tmp = code(cosTheta_i, u1, u2) tmp = single(2.0) * ((u1 ^ single(0.5)) * (u2 * single(pi))); end
\begin{array}{l}
\\
2 \cdot \left({u1}^{0.5} \cdot \left(u2 \cdot \pi\right)\right)
\end{array}
Initial program 56.5%
Taylor expanded in u1 around 0 77.5%
Taylor expanded in u2 around 0 66.9%
pow1/277.5%
Applied egg-rr66.9%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* 2.0 (* (sqrt u1) (* u2 PI))))
float code(float cosTheta_i, float u1, float u2) {
return 2.0f * (sqrtf(u1) * (u2 * ((float) M_PI)));
}
function code(cosTheta_i, u1, u2) return Float32(Float32(2.0) * Float32(sqrt(u1) * Float32(u2 * Float32(pi)))) end
function tmp = code(cosTheta_i, u1, u2) tmp = single(2.0) * (sqrt(u1) * (u2 * single(pi))); end
\begin{array}{l}
\\
2 \cdot \left(\sqrt{u1} \cdot \left(u2 \cdot \pi\right)\right)
\end{array}
Initial program 56.5%
Taylor expanded in u1 around 0 77.5%
Taylor expanded in u2 around 0 66.9%
herbie shell --seed 2024185
(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))))