
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (sin (* (* 2.0 (PI)) u2))))
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 13 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt (- (log (- 1.0 u1)))) (sin (* (* 2.0 (PI)) u2))))
\begin{array}{l}
\\
\sqrt{-\log \left(1 - u1\right)} \cdot \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)
\end{array}
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (sin (* (* 2.0 (PI)) u2))))
(if (<= u1 0.03500000014901161)
(*
(sqrt
(-
(*
(-
(/ (+ (+ 0.3333333333333333 (/ 1.0 (* u1 u1))) (/ 0.5 u1)) (- u1))
0.25)
(pow u1 4.0))))
t_0)
(* (pow (pow (- (log (- 1.0 u1))) 0.25) 2.0) t_0))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)\\
\mathbf{if}\;u1 \leq 0.03500000014901161:\\
\;\;\;\;\sqrt{-\left(\frac{\left(0.3333333333333333 + \frac{1}{u1 \cdot u1}\right) + \frac{0.5}{u1}}{-u1} - 0.25\right) \cdot {u1}^{4}} \cdot t\_0\\
\mathbf{else}:\\
\;\;\;\;{\left({\left(-\log \left(1 - u1\right)\right)}^{0.25}\right)}^{2} \cdot t\_0\\
\end{array}
\end{array}
if u1 < 0.0350000001Initial program 53.2%
Taylor expanded in u1 around 0
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower--.f32N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f3298.2
Applied rewrites98.2%
Taylor expanded in u1 around -inf
Applied rewrites98.3%
if 0.0350000001 < u1 Initial program 97.3%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3296.8
Applied rewrites96.8%
Applied rewrites97.3%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (log (- 1.0 u1)))
(t_1
(*
(- (* (- (* (- (* -0.25 u1) 0.3333333333333333) u1) 0.5) u1) 1.0)
u1))
(t_2 (sin (* (* 2.0 (PI)) u2))))
(if (<= t_0 -0.03999999910593033)
(* (sqrt (- t_0)) t_2)
(* (pow (* t_1 t_1) 0.25) t_2))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \log \left(1 - u1\right)\\
t_1 := \left(\left(\left(-0.25 \cdot u1 - 0.3333333333333333\right) \cdot u1 - 0.5\right) \cdot u1 - 1\right) \cdot u1\\
t_2 := \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)\\
\mathbf{if}\;t\_0 \leq -0.03999999910593033:\\
\;\;\;\;\sqrt{-t\_0} \cdot t\_2\\
\mathbf{else}:\\
\;\;\;\;{\left(t\_1 \cdot t\_1\right)}^{0.25} \cdot t\_2\\
\end{array}
\end{array}
if (log.f32 (-.f32 #s(literal 1 binary32) u1)) < -0.0399999991Initial program 97.3%
if -0.0399999991 < (log.f32 (-.f32 #s(literal 1 binary32) u1)) Initial program 53.2%
Taylor expanded in u1 around 0
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower--.f32N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f3298.2
Applied rewrites98.2%
lift-sqrt.f32N/A
pow1/2N/A
metadata-evalN/A
metadata-evalN/A
metadata-evalN/A
pow-prod-upN/A
pow-prod-downN/A
lower-pow.f32N/A
lower-*.f32N/A
metadata-eval98.3
Applied rewrites98.3%
lift-*.f32N/A
lift-neg.f32N/A
lift-neg.f32N/A
sqr-negN/A
lower-*.f3298.3
Applied rewrites98.3%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (log (- 1.0 u1))) (t_1 (sin (* (* 2.0 (PI)) u2))))
(if (<= t_0 -0.03999999910593033)
(* (sqrt (- t_0)) t_1)
(*
(sqrt
(-
(*
(- (/ (- (/ (- (/ -1.0 u1) 0.5) u1) 0.3333333333333333) u1) 0.25)
(pow u1 4.0))))
t_1))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \log \left(1 - u1\right)\\
t_1 := \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)\\
\mathbf{if}\;t\_0 \leq -0.03999999910593033:\\
\;\;\;\;\sqrt{-t\_0} \cdot t\_1\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\left(\frac{\frac{\frac{-1}{u1} - 0.5}{u1} - 0.3333333333333333}{u1} - 0.25\right) \cdot {u1}^{4}} \cdot t\_1\\
\end{array}
\end{array}
if (log.f32 (-.f32 #s(literal 1 binary32) u1)) < -0.0399999991Initial program 97.3%
if -0.0399999991 < (log.f32 (-.f32 #s(literal 1 binary32) u1)) Initial program 53.2%
Taylor expanded in u1 around 0
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower--.f32N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f3298.2
Applied rewrites98.2%
Taylor expanded in u1 around -inf
Applied rewrites98.3%
Applied rewrites98.3%
Final simplification98.1%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (log (- 1.0 u1))) (t_1 (sin (* (* 2.0 (PI)) u2))))
(if (<= t_0 -0.03999999910593033)
(* (sqrt (- t_0)) t_1)
(*
(sqrt
(-
(*
(- (* (- (* (- (* -0.25 u1) 0.3333333333333333) u1) 0.5) u1) 1.0)
u1)))
t_1))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \log \left(1 - u1\right)\\
t_1 := \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)\\
\mathbf{if}\;t\_0 \leq -0.03999999910593033:\\
\;\;\;\;\sqrt{-t\_0} \cdot t\_1\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\left(\left(\left(-0.25 \cdot u1 - 0.3333333333333333\right) \cdot u1 - 0.5\right) \cdot u1 - 1\right) \cdot u1} \cdot t\_1\\
\end{array}
\end{array}
if (log.f32 (-.f32 #s(literal 1 binary32) u1)) < -0.0399999991Initial program 97.3%
if -0.0399999991 < (log.f32 (-.f32 #s(literal 1 binary32) u1)) Initial program 53.2%
Taylor expanded in u1 around 0
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower--.f32N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f3298.2
Applied rewrites98.2%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (sin (* (* 2.0 (PI)) u2))))
(if (<= u1 0.030500000342726707)
(*
(sqrt
(-
(*
(-
(/ (+ (+ 0.3333333333333333 (/ 1.0 (* u1 u1))) (/ 0.5 u1)) (- u1))
0.25)
(pow u1 4.0))))
t_0)
(* (sqrt (- (log (- 1.0 u1)))) t_0))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)\\
\mathbf{if}\;u1 \leq 0.030500000342726707:\\
\;\;\;\;\sqrt{-\left(\frac{\left(0.3333333333333333 + \frac{1}{u1 \cdot u1}\right) + \frac{0.5}{u1}}{-u1} - 0.25\right) \cdot {u1}^{4}} \cdot t\_0\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\log \left(1 - u1\right)} \cdot t\_0\\
\end{array}
\end{array}
if u1 < 0.0305000003Initial program 53.0%
Taylor expanded in u1 around 0
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower--.f32N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f3298.2
Applied rewrites98.2%
Taylor expanded in u1 around -inf
Applied rewrites98.3%
if 0.0305000003 < u1 Initial program 97.3%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (log (- 1.0 u1))))
(if (<= t_0 -0.20000000298023224)
(* (* (* (PI) u2) 2.0) (sqrt (- t_0)))
(*
(sqrt
(-
(*
(- (* (- (* (- (* -0.25 u1) 0.3333333333333333) u1) 0.5) u1) 1.0)
u1)))
(sin (* (* 2.0 (PI)) u2))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \log \left(1 - u1\right)\\
\mathbf{if}\;t\_0 \leq -0.20000000298023224:\\
\;\;\;\;\left(\left(\mathsf{PI}\left(\right) \cdot u2\right) \cdot 2\right) \cdot \sqrt{-t\_0}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\left(\left(\left(-0.25 \cdot u1 - 0.3333333333333333\right) \cdot u1 - 0.5\right) \cdot u1 - 1\right) \cdot u1} \cdot \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)\\
\end{array}
\end{array}
if (log.f32 (-.f32 #s(literal 1 binary32) u1)) < -0.200000003Initial program 98.0%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3298.0
Applied rewrites98.0%
Taylor expanded in u1 around 0
lower-sqrt.f3235.0
Applied rewrites35.0%
Taylor expanded in u2 around 0
associate-*r*N/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-sqrt.f32N/A
log-recN/A
lower-neg.f32N/A
lower-log.f32N/A
lower--.f3282.1
Applied rewrites82.1%
if -0.200000003 < (log.f32 (-.f32 #s(literal 1 binary32) u1)) Initial program 56.2%
Taylor expanded in u1 around 0
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
metadata-evalN/A
distribute-lft-neg-inN/A
lower--.f32N/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f3297.1
Applied rewrites97.1%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (log (- 1.0 u1))))
(if (<= t_0 -0.04050000011920929)
(* (* (* (PI) u2) 2.0) (sqrt (- t_0)))
(*
(sqrt (- (* (- (* (- (* -0.3333333333333333 u1) 0.5) u1) 1.0) u1)))
(sin (* (* 2.0 (PI)) u2))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \log \left(1 - u1\right)\\
\mathbf{if}\;t\_0 \leq -0.04050000011920929:\\
\;\;\;\;\left(\left(\mathsf{PI}\left(\right) \cdot u2\right) \cdot 2\right) \cdot \sqrt{-t\_0}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\left(\left(-0.3333333333333333 \cdot u1 - 0.5\right) \cdot u1 - 1\right) \cdot u1} \cdot \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)\\
\end{array}
\end{array}
if (log.f32 (-.f32 #s(literal 1 binary32) u1)) < -0.0405000001Initial program 97.2%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3296.8
Applied rewrites96.8%
Taylor expanded in u1 around 0
lower-sqrt.f3238.2
Applied rewrites38.2%
Taylor expanded in u2 around 0
associate-*r*N/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-sqrt.f32N/A
log-recN/A
lower-neg.f32N/A
lower-log.f32N/A
lower--.f3279.7
Applied rewrites79.7%
if -0.0405000001 < (log.f32 (-.f32 #s(literal 1 binary32) u1)) Initial program 53.5%
Taylor expanded in u1 around 0
*-commutativeN/A
lower-*.f32N/A
lower--.f32N/A
*-commutativeN/A
lower-*.f32N/A
metadata-evalN/A
distribute-lft-neg-inN/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower--.f32N/A
distribute-lft-neg-inN/A
*-commutativeN/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f3297.5
Applied rewrites97.5%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (log (- 1.0 u1))))
(if (<= t_0 -0.009999999776482582)
(* (* (* (PI) u2) 2.0) (sqrt (- t_0)))
(* (sqrt (- (* (- (* -0.5 u1) 1.0) u1))) (sin (* (* 2.0 (PI)) u2))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \log \left(1 - u1\right)\\
\mathbf{if}\;t\_0 \leq -0.009999999776482582:\\
\;\;\;\;\left(\left(\mathsf{PI}\left(\right) \cdot u2\right) \cdot 2\right) \cdot \sqrt{-t\_0}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{-\left(-0.5 \cdot u1 - 1\right) \cdot u1} \cdot \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)\\
\end{array}
\end{array}
if (log.f32 (-.f32 #s(literal 1 binary32) u1)) < -0.00999999978Initial program 97.0%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3295.3
Applied rewrites95.3%
Taylor expanded in u1 around 0
lower-sqrt.f3241.4
Applied rewrites41.4%
Taylor expanded in u2 around 0
associate-*r*N/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-sqrt.f32N/A
log-recN/A
lower-neg.f32N/A
lower-log.f32N/A
lower--.f3279.6
Applied rewrites79.6%
if -0.00999999978 < (log.f32 (-.f32 #s(literal 1 binary32) u1)) Initial program 50.5%
Taylor expanded in u1 around 0
*-commutativeN/A
lower-*.f32N/A
metadata-evalN/A
distribute-lft-neg-inN/A
*-commutativeN/A
distribute-lft-neg-inN/A
lower--.f32N/A
distribute-lft-neg-inN/A
*-commutativeN/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-*.f3296.9
Applied rewrites96.9%
(FPCore (cosTheta_i u1 u2)
:precision binary32
(let* ((t_0 (log (- 1.0 u1))))
(if (<= t_0 -0.0007200000109151006)
(* (* (* (PI) u2) 2.0) (sqrt (- t_0)))
(* (sqrt u1) (sin (* (* 2.0 (PI)) u2))))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \log \left(1 - u1\right)\\
\mathbf{if}\;t\_0 \leq -0.0007200000109151006:\\
\;\;\;\;\left(\left(\mathsf{PI}\left(\right) \cdot u2\right) \cdot 2\right) \cdot \sqrt{-t\_0}\\
\mathbf{else}:\\
\;\;\;\;\sqrt{u1} \cdot \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)\\
\end{array}
\end{array}
if (log.f32 (-.f32 #s(literal 1 binary32) u1)) < -7.20000011e-4Initial program 92.5%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3290.8
Applied rewrites90.8%
Taylor expanded in u1 around 0
lower-sqrt.f3247.7
Applied rewrites47.7%
Taylor expanded in u2 around 0
associate-*r*N/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-sqrt.f32N/A
log-recN/A
lower-neg.f32N/A
lower-log.f32N/A
lower--.f3276.1
Applied rewrites76.1%
if -7.20000011e-4 < (log.f32 (-.f32 #s(literal 1 binary32) u1)) Initial program 45.1%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3242.4
Applied rewrites42.4%
Taylor expanded in u1 around 0
lower-sqrt.f3288.4
Applied rewrites88.4%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt u1) (sin (* (* 2.0 (PI)) u2))))
\begin{array}{l}
\\
\sqrt{u1} \cdot \sin \left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot u2\right)
\end{array}
Initial program 60.5%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3258.1
Applied rewrites58.1%
Taylor expanded in u1 around 0
lower-sqrt.f3275.2
Applied rewrites75.2%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (pow (* u1 u1) 0.25) (* (* (PI) u2) 2.0)))
\begin{array}{l}
\\
{\left(u1 \cdot u1\right)}^{0.25} \cdot \left(\left(\mathsf{PI}\left(\right) \cdot u2\right) \cdot 2\right)
\end{array}
Initial program 60.5%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3258.1
Applied rewrites58.1%
Taylor expanded in u1 around 0
lower-sqrt.f3275.2
Applied rewrites75.2%
Taylor expanded in u2 around 0
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3263.1
Applied rewrites63.1%
Applied rewrites63.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (pow u1 0.5) (* (* (PI) u2) 2.0)))
\begin{array}{l}
\\
{u1}^{0.5} \cdot \left(\left(\mathsf{PI}\left(\right) \cdot u2\right) \cdot 2\right)
\end{array}
Initial program 60.5%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3258.1
Applied rewrites58.1%
Taylor expanded in u1 around 0
lower-sqrt.f3275.2
Applied rewrites75.2%
Taylor expanded in u2 around 0
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3263.1
Applied rewrites63.1%
Applied rewrites63.1%
(FPCore (cosTheta_i u1 u2) :precision binary32 (* (sqrt u1) (* (* (PI) u2) 2.0)))
\begin{array}{l}
\\
\sqrt{u1} \cdot \left(\left(\mathsf{PI}\left(\right) \cdot u2\right) \cdot 2\right)
\end{array}
Initial program 60.5%
lift-neg.f32N/A
lift-log.f32N/A
neg-logN/A
lower-log.f32N/A
lower-/.f3258.1
Applied rewrites58.1%
Taylor expanded in u1 around 0
lower-sqrt.f3275.2
Applied rewrites75.2%
Taylor expanded in u2 around 0
*-commutativeN/A
lower-*.f32N/A
*-commutativeN/A
lower-*.f32N/A
lower-PI.f3263.1
Applied rewrites63.1%
herbie shell --seed 2024337
(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))))