
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (cos (* (* 2.0 PI) u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-logf((1.0f - u1))) * cosf(((2.0f * ((float) M_PI)) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log(Float32(Float32(1.0) - u1)))) * cos(Float32(Float32(Float32(2.0) * Float32(pi)) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(-log((single(1.0) - u1))) * cos(((single(2.0) * single(pi)) * u2)); end
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right)
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 12 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (cos (* (* 2.0 PI) u2))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-logf((1.0f - u1))) * cosf(((2.0f * ((float) M_PI)) * u2));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log(Float32(Float32(1.0) - u1)))) * cos(Float32(Float32(Float32(2.0) * Float32(pi)) * u2))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(-log((single(1.0) - u1))) * cos(((single(2.0) * single(pi)) * u2)); end
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \cos \left(\left(2 \cdot \pi\right) \cdot u2\right)
\end{array}
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (cos (* u2 (* 2.0 PI)))))
(*
(sqrt (- (log1p (- u1))))
(+
t_0
(-
(+ 0.5 (* t_0 -0.5))
(* (sin (* u2 PI)) (sin (cbrt (* (pow PI 3.0) (pow u2 3.0))))))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = cosf((u2 * (2.0f * ((float) M_PI))));
return sqrtf(-log1pf(-u1)) * (t_0 + ((0.5f + (t_0 * -0.5f)) - (sinf((u2 * ((float) M_PI))) * sinf(cbrtf((powf(((float) M_PI), 3.0f) * powf(u2, 3.0f)))))));
}
function code(cosTheta_i, u1, u2) t_0 = cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * Float32(t_0 + Float32(Float32(Float32(0.5) + Float32(t_0 * Float32(-0.5))) - Float32(sin(Float32(u2 * Float32(pi))) * sin(cbrt(Float32((Float32(pi) ^ Float32(3.0)) * (u2 ^ Float32(3.0))))))))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \cos \left(u2 \cdot \left(2 \cdot \pi\right)\right)\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \left(t\_0 + \left(\left(0.5 + t\_0 \cdot -0.5\right) - \sin \left(u2 \cdot \pi\right) \cdot \sin \left(\sqrt[3]{{\pi}^{3} \cdot {u2}^{3}}\right)\right)\right)
\end{array}
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
associate-*l*99.1%
cos-299.0%
prod-diff99.1%
fma-neg99.0%
cos-299.1%
associate-*l*99.1%
*-commutative99.1%
associate-*l*99.1%
sqr-sin-a99.1%
associate-*l*99.1%
Applied egg-rr99.1%
*-commutative99.1%
*-commutative99.1%
associate-*l*99.1%
fma-undefine99.1%
+-commutative99.1%
distribute-lft-neg-out99.1%
unsub-neg99.1%
Simplified99.1%
*-commutative99.1%
add-cbrt-cube99.1%
add-cbrt-cube99.1%
cbrt-unprod99.2%
pow399.2%
pow399.2%
Applied egg-rr99.2%
Final simplification99.2%
(FPCore (cosTheta_i u1 u2) :precision binary32 (let* ((t_0 (sin (* u2 PI))) (t_1 (cos (* u2 (* 2.0 PI))))) (* (sqrt (- (log1p (- u1)))) (+ t_1 (- (+ 0.5 (* t_1 -0.5)) (* t_0 t_0))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = sinf((u2 * ((float) M_PI)));
float t_1 = cosf((u2 * (2.0f * ((float) M_PI))));
return sqrtf(-log1pf(-u1)) * (t_1 + ((0.5f + (t_1 * -0.5f)) - (t_0 * t_0)));
}
function code(cosTheta_i, u1, u2) t_0 = sin(Float32(u2 * Float32(pi))) t_1 = cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * Float32(t_1 + Float32(Float32(Float32(0.5) + Float32(t_1 * Float32(-0.5))) - Float32(t_0 * t_0)))) end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(u2 \cdot \pi\right)\\
t_1 := \cos \left(u2 \cdot \left(2 \cdot \pi\right)\right)\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \left(t\_1 + \left(\left(0.5 + t\_1 \cdot -0.5\right) - t\_0 \cdot t\_0\right)\right)
\end{array}
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
associate-*l*99.1%
cos-299.0%
prod-diff99.1%
fma-neg99.0%
cos-299.1%
associate-*l*99.1%
*-commutative99.1%
associate-*l*99.1%
sqr-sin-a99.1%
associate-*l*99.1%
Applied egg-rr99.1%
*-commutative99.1%
*-commutative99.1%
associate-*l*99.1%
fma-undefine99.1%
+-commutative99.1%
distribute-lft-neg-out99.1%
unsub-neg99.1%
Simplified99.1%
Final simplification99.1%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (cos (* u2 (* 2.0 PI)))))
(if (<= t_0 0.9999589920043945)
(* t_0 (sqrt u1))
(sqrt (- (log1p (- u1)))))))
float code(float cosTheta_i, float u1, float u2) {
float t_0 = cosf((u2 * (2.0f * ((float) M_PI))));
float tmp;
if (t_0 <= 0.9999589920043945f) {
tmp = t_0 * sqrtf(u1);
} else {
tmp = sqrtf(-log1pf(-u1));
}
return tmp;
}
function code(cosTheta_i, u1, u2) t_0 = cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi)))) tmp = Float32(0.0) if (t_0 <= Float32(0.9999589920043945)) tmp = Float32(t_0 * sqrt(u1)); else tmp = sqrt(Float32(-log1p(Float32(-u1)))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \cos \left(u2 \cdot \left(2 \cdot \pi\right)\right)\\
\mathbf{if}\;t\_0 \leq 0.9999589920043945:\\
\;\;\;\;t\_0 \cdot \sqrt{u1}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)}\\
\end{array}
\end{array}
if (cos.f32 (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2)) < 0.99995899Initial program 54.2%
sub-neg54.2%
log1p-define97.8%
Simplified97.8%
add-cbrt-cube97.8%
pow1/394.9%
Applied egg-rr76.7%
Taylor expanded in u1 around 0 80.4%
if 0.99995899 < (cos.f32 (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2)) Initial program 57.6%
sub-neg57.6%
log1p-define99.5%
Simplified99.5%
Taylor expanded in u2 around 0 96.6%
Final simplification92.4%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log1p (- u1)))) (cos (* u2 (* 2.0 PI)))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-log1pf(-u1)) * cosf((u2 * (2.0f * ((float) M_PI))));
}
function code(cosTheta_i, u1, u2) return Float32(sqrt(Float32(-log1p(Float32(-u1)))) * cos(Float32(u2 * Float32(Float32(2.0) * Float32(pi))))) end
\begin{array}{l}
\\
\sqrt{-\mathsf{log1p}\left(-u1\right)} \cdot \cos \left(u2 \cdot \left(2 \cdot \pi\right)\right)
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
Final simplification99.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (if (<= (* u2 (* 2.0 PI)) 0.0013500000350177288) (sqrt (- (log1p (- u1)))) (* (* u1 (cos (* 2.0 (* u2 PI)))) (sqrt (+ 0.5 (/ 1.0 u1))))))
float code(float cosTheta_i, float u1, float u2) {
float tmp;
if ((u2 * (2.0f * ((float) M_PI))) <= 0.0013500000350177288f) {
tmp = sqrtf(-log1pf(-u1));
} else {
tmp = (u1 * cosf((2.0f * (u2 * ((float) M_PI))))) * sqrtf((0.5f + (1.0f / u1)));
}
return tmp;
}
function code(cosTheta_i, u1, u2) tmp = Float32(0.0) if (Float32(u2 * Float32(Float32(2.0) * Float32(pi))) <= Float32(0.0013500000350177288)) tmp = sqrt(Float32(-log1p(Float32(-u1)))); else tmp = Float32(Float32(u1 * cos(Float32(Float32(2.0) * Float32(u2 * Float32(pi))))) * sqrt(Float32(Float32(0.5) + Float32(Float32(1.0) / u1)))); end return tmp end
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;u2 \cdot \left(2 \cdot \pi\right) \leq 0.0013500000350177288:\\
\;\;\;\;\sqrt{-\mathsf{log1p}\left(-u1\right)}\\
\mathbf{else}:\\
\;\;\;\;\left(u1 \cdot \cos \left(2 \cdot \left(u2 \cdot \pi\right)\right)\right) \cdot \sqrt{0.5 + \frac{1}{u1}}\\
\end{array}
\end{array}
if (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) < 0.00135000004Initial program 57.1%
sub-neg57.1%
log1p-define99.6%
Simplified99.6%
Taylor expanded in u2 around 0 99.2%
if 0.00135000004 < (*.f32 (*.f32 #s(literal 2 binary32) (PI.f32)) u2) Initial program 56.1%
sub-neg56.1%
log1p-define98.2%
Simplified98.2%
add-cube-cbrt97.3%
pow397.2%
*-commutative97.2%
associate-*l*97.2%
Applied egg-rr97.2%
Taylor expanded in u1 around 0 87.9%
Taylor expanded in u1 around inf 87.9%
mul-1-neg87.9%
distribute-rgt-neg-in87.9%
+-commutative87.9%
Simplified87.9%
Taylor expanded in u2 around inf 88.3%
Final simplification95.3%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt (- (log1p (- u1)))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(-log1pf(-u1));
}
function code(cosTheta_i, u1, u2) return sqrt(Float32(-log1p(Float32(-u1)))) end
\begin{array}{l}
\\
\sqrt{-\mathsf{log1p}\left(-u1\right)}
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 81.3%
Final simplification81.3%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt (* u1 (+ 1.0 (* u1 (+ 0.5 (* u1 (- 0.3333333333333333 (* u1 -0.25)))))))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 * (1.0f + (u1 * (0.5f + (u1 * (0.3333333333333333f - (u1 * -0.25f))))))));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 * (1.0e0 + (u1 * (0.5e0 + (u1 * (0.3333333333333333e0 - (u1 * (-0.25e0)))))))))
end function
function code(cosTheta_i, u1, u2) return 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
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 * (single(1.0) + (u1 * (single(0.5) + (u1 * (single(0.3333333333333333) - (u1 * single(-0.25))))))))); end
\begin{array}{l}
\\
\sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 + u1 \cdot \left(0.3333333333333333 - u1 \cdot -0.25\right)\right)\right)}
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 81.3%
Taylor expanded in u1 around 0 77.5%
Final simplification77.5%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt (* u1 (+ 1.0 (* u1 (- 0.5 (* u1 -0.3333333333333333)))))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 * (1.0f + (u1 * (0.5f - (u1 * -0.3333333333333333f))))));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 * (1.0e0 + (u1 * (0.5e0 - (u1 * (-0.3333333333333333e0)))))))
end function
function code(cosTheta_i, u1, u2) return sqrt(Float32(u1 * Float32(Float32(1.0) + Float32(u1 * Float32(Float32(0.5) - Float32(u1 * Float32(-0.3333333333333333))))))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 * (single(1.0) + (u1 * (single(0.5) - (u1 * single(-0.3333333333333333))))))); end
\begin{array}{l}
\\
\sqrt{u1 \cdot \left(1 + u1 \cdot \left(0.5 - u1 \cdot -0.3333333333333333\right)\right)}
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 81.3%
Taylor expanded in u1 around 0 76.1%
Final simplification76.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* u1 (sqrt (+ 0.5 (/ 1.0 u1)))))
float code(float cosTheta_i, float u1, float u2) {
return u1 * sqrtf((0.5f + (1.0f / u1)));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = u1 * sqrt((0.5e0 + (1.0e0 / u1)))
end function
function code(cosTheta_i, u1, u2) return Float32(u1 * sqrt(Float32(Float32(0.5) + Float32(Float32(1.0) / u1)))) end
function tmp = code(cosTheta_i, u1, u2) tmp = u1 * sqrt((single(0.5) + (single(1.0) / u1))); end
\begin{array}{l}
\\
u1 \cdot \sqrt{0.5 + \frac{1}{u1}}
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
add-cube-cbrt98.7%
pow398.7%
*-commutative98.7%
associate-*l*98.7%
Applied egg-rr98.7%
Taylor expanded in u1 around 0 88.7%
Taylor expanded in u1 around inf 88.6%
mul-1-neg88.6%
distribute-rgt-neg-in88.6%
+-commutative88.6%
Simplified88.6%
Taylor expanded in u2 around 0 73.8%
Final simplification73.8%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt (* u1 (- 1.0 (* u1 -0.5)))))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf((u1 * (1.0f - (u1 * -0.5f))));
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt((u1 * (1.0e0 - (u1 * (-0.5e0)))))
end function
function code(cosTheta_i, u1, u2) return sqrt(Float32(u1 * Float32(Float32(1.0) - Float32(u1 * Float32(-0.5))))) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt((u1 * (single(1.0) - (u1 * single(-0.5))))); end
\begin{array}{l}
\\
\sqrt{u1 \cdot \left(1 - u1 \cdot -0.5\right)}
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 81.3%
Taylor expanded in u1 around 0 74.0%
Final simplification74.0%
(FPCore (cosTheta_i u1 u2) :precision binary32 (- (sqrt u1)))
float code(float cosTheta_i, float u1, float u2) {
return -sqrtf(u1);
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = -sqrt(u1)
end function
function code(cosTheta_i, u1, u2) return Float32(-sqrt(u1)) end
function tmp = code(cosTheta_i, u1, u2) tmp = -sqrt(u1); end
\begin{array}{l}
\\
-\sqrt{u1}
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 81.3%
Taylor expanded in u1 around 0 -0.0%
*-commutative-0.0%
unpow2-0.0%
rem-square-sqrt5.1%
mul-1-neg5.1%
Simplified5.1%
Final simplification5.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (sqrt u1))
float code(float cosTheta_i, float u1, float u2) {
return sqrtf(u1);
}
real(4) function code(costheta_i, u1, u2)
real(4), intent (in) :: costheta_i
real(4), intent (in) :: u1
real(4), intent (in) :: u2
code = sqrt(u1)
end function
function code(cosTheta_i, u1, u2) return sqrt(u1) end
function tmp = code(cosTheta_i, u1, u2) tmp = sqrt(u1); end
\begin{array}{l}
\\
\sqrt{u1}
\end{array}
Initial program 56.7%
sub-neg56.7%
log1p-define99.1%
Simplified99.1%
Taylor expanded in u2 around 0 81.3%
Taylor expanded in u1 around 0 66.0%
Simplified66.0%
Final simplification66.0%
herbie shell --seed 2024078
(FPCore (cosTheta_i u1 u2)
:name "Beckmann Sample, near normal, slope_x"
: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)))) (cos (* (* 2.0 PI) u2))))