
(FPCore (u s)
:precision binary32
(let* ((t_0 (/ 1.0 (+ 1.0 (exp (/ (PI) s))))))
(*
(- s)
(log
(-
(/ 1.0 (+ (* u (- (/ 1.0 (+ 1.0 (exp (/ (- (PI)) s)))) t_0)) t_0))
1.0)))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{1 + e^{\frac{\mathsf{PI}\left(\right)}{s}}}\\
\left(-s\right) \cdot \log \left(\frac{1}{u \cdot \left(\frac{1}{1 + e^{\frac{-\mathsf{PI}\left(\right)}{s}}} - t\_0\right) + t\_0} - 1\right)
\end{array}
\end{array}
Sampling outcomes in binary32 precision:
Herbie found 12 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (u s)
:precision binary32
(let* ((t_0 (/ 1.0 (+ 1.0 (exp (/ (PI) s))))))
(*
(- s)
(log
(-
(/ 1.0 (+ (* u (- (/ 1.0 (+ 1.0 (exp (/ (- (PI)) s)))) t_0)) t_0))
1.0)))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{1 + e^{\frac{\mathsf{PI}\left(\right)}{s}}}\\
\left(-s\right) \cdot \log \left(\frac{1}{u \cdot \left(\frac{1}{1 + e^{\frac{-\mathsf{PI}\left(\right)}{s}}} - t\_0\right) + t\_0} - 1\right)
\end{array}
\end{array}
(FPCore (u s)
:precision binary32
(let* ((t_0 (/ (PI) s)))
(*
(log
(-
(/
1.0
(-
(/ 1.0 (+ (pow (E) t_0) 1.0))
(*
(- (/ -1.0 (+ (exp (/ (- (PI)) s)) 1.0)) (/ -1.0 (+ (exp t_0) 1.0)))
u)))
1.0))
(- s))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{\mathsf{PI}\left(\right)}{s}\\
\log \left(\frac{1}{\frac{1}{{\mathsf{E}\left(\right)}^{t\_0} + 1} - \left(\frac{-1}{e^{\frac{-\mathsf{PI}\left(\right)}{s}} + 1} - \frac{-1}{e^{t\_0} + 1}\right) \cdot u} - 1\right) \cdot \left(-s\right)
\end{array}
\end{array}
Initial program 99.1%
lift-exp.f32N/A
lift-/.f32N/A
clear-numN/A
div-invN/A
clear-numN/A
lift-/.f32N/A
exp-prodN/A
lower-pow.f32N/A
exp-1-eN/A
lower-E.f3299.1
Applied rewrites99.1%
Final simplification99.1%
(FPCore (u s)
:precision binary32
(let* ((t_0 (- (PI))) (t_1 (/ -1.0 (+ (exp (/ (PI) s)) 1.0))))
(if (<=
(*
(log
(-
-1.0
(/ -1.0 (- (* (- t_1 (/ -1.0 (+ (exp (/ t_0 s)) 1.0))) u) t_1))))
(- s))
-1.3999999555717316e-19)
t_0
(* (fma 2.0 (PI) 0.0) u))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := -\mathsf{PI}\left(\right)\\
t_1 := \frac{-1}{e^{\frac{\mathsf{PI}\left(\right)}{s}} + 1}\\
\mathbf{if}\;\log \left(-1 - \frac{-1}{\left(t\_1 - \frac{-1}{e^{\frac{t\_0}{s}} + 1}\right) \cdot u - t\_1}\right) \cdot \left(-s\right) \leq -1.3999999555717316 \cdot 10^{-19}:\\
\;\;\;\;t\_0\\
\mathbf{else}:\\
\;\;\;\;\mathsf{fma}\left(2, \mathsf{PI}\left(\right), 0\right) \cdot u\\
\end{array}
\end{array}
if (*.f32 (neg.f32 s) (log.f32 (-.f32 (/.f32 #s(literal 1 binary32) (+.f32 (*.f32 u (-.f32 (/.f32 #s(literal 1 binary32) (+.f32 #s(literal 1 binary32) (exp.f32 (/.f32 (neg.f32 (PI.f32)) s)))) (/.f32 #s(literal 1 binary32) (+.f32 #s(literal 1 binary32) (exp.f32 (/.f32 (PI.f32) s)))))) (/.f32 #s(literal 1 binary32) (+.f32 #s(literal 1 binary32) (exp.f32 (/.f32 (PI.f32) s)))))) #s(literal 1 binary32)))) < -1.39999996e-19Initial program 99.2%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f3215.5
Applied rewrites15.5%
if -1.39999996e-19 < (*.f32 (neg.f32 s) (log.f32 (-.f32 (/.f32 #s(literal 1 binary32) (+.f32 (*.f32 u (-.f32 (/.f32 #s(literal 1 binary32) (+.f32 #s(literal 1 binary32) (exp.f32 (/.f32 (neg.f32 (PI.f32)) s)))) (/.f32 #s(literal 1 binary32) (+.f32 #s(literal 1 binary32) (exp.f32 (/.f32 (PI.f32) s)))))) (/.f32 #s(literal 1 binary32) (+.f32 #s(literal 1 binary32) (exp.f32 (/.f32 (PI.f32) s)))))) #s(literal 1 binary32)))) Initial program 99.0%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f327.5
Applied rewrites7.5%
Taylor expanded in s around -inf
*-commutativeN/A
lower-*.f32N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-out--N/A
metadata-evalN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
distribute-rgt-outN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-fma.f327.5
Applied rewrites7.5%
Taylor expanded in u around inf
Applied rewrites5.8%
Applied rewrites13.3%
Final simplification11.1%
(FPCore (u s)
:precision binary32
(let* ((t_0 (/ -1.0 (+ (exp (/ (PI) s)) 1.0))))
(*
(log
(-
-1.0
(/ -1.0 (- (* (- t_0 (/ -1.0 (+ (exp (/ (- (PI)) s)) 1.0))) u) t_0))))
(- s))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{-1}{e^{\frac{\mathsf{PI}\left(\right)}{s}} + 1}\\
\log \left(-1 - \frac{-1}{\left(t\_0 - \frac{-1}{e^{\frac{-\mathsf{PI}\left(\right)}{s}} + 1}\right) \cdot u - t\_0}\right) \cdot \left(-s\right)
\end{array}
\end{array}
Initial program 99.1%
Final simplification99.1%
(FPCore (u s)
:precision binary32
(let* ((t_0 (/ (PI) s)))
(*
(log
(-
-1.0
(/
-1.0
(-
(*
(-
(/ -1.0 (+ (- 1.0 (/ (- (* -0.5 (* t_0 (PI))) (PI)) s)) 1.0))
(/ -1.0 (+ (exp (/ (- (PI)) s)) 1.0)))
u)
(/ -1.0 (+ (exp t_0) 1.0))))))
(- s))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{\mathsf{PI}\left(\right)}{s}\\
\log \left(-1 - \frac{-1}{\left(\frac{-1}{\left(1 - \frac{-0.5 \cdot \left(t\_0 \cdot \mathsf{PI}\left(\right)\right) - \mathsf{PI}\left(\right)}{s}\right) + 1} - \frac{-1}{e^{\frac{-\mathsf{PI}\left(\right)}{s}} + 1}\right) \cdot u - \frac{-1}{e^{t\_0} + 1}}\right) \cdot \left(-s\right)
\end{array}
\end{array}
Initial program 99.1%
Taylor expanded in s around -inf
mul-1-negN/A
unsub-negN/A
lower--.f32N/A
lower-/.f32N/A
Applied rewrites97.6%
Final simplification97.6%
(FPCore (u s)
:precision binary32
(*
(log
(-
-1.0
(/
(/ -1.0 u)
(-
(/ -1.0 (+ (exp (/ (PI) s)) 1.0))
(/ -1.0 (+ (exp (/ (- (PI)) s)) 1.0))))))
(- s)))\begin{array}{l}
\\
\log \left(-1 - \frac{\frac{-1}{u}}{\frac{-1}{e^{\frac{\mathsf{PI}\left(\right)}{s}} + 1} - \frac{-1}{e^{\frac{-\mathsf{PI}\left(\right)}{s}} + 1}}\right) \cdot \left(-s\right)
\end{array}
Initial program 99.1%
Taylor expanded in s around inf
distribute-rgt-out--N/A
metadata-evalN/A
associate-*r*N/A
metadata-evalN/A
distribute-rgt-neg-inN/A
associate-*r*N/A
metadata-evalN/A
distribute-rgt-out--N/A
distribute-neg-fracN/A
distribute-neg-frac2N/A
mul-1-negN/A
distribute-rgt-out--N/A
metadata-evalN/A
associate-*r*N/A
*-commutativeN/A
times-fracN/A
metadata-evalN/A
Applied rewrites3.1%
Taylor expanded in u around inf
lower--.f32N/A
Applied rewrites97.6%
Final simplification97.6%
(FPCore (u s)
:precision binary32
(let* ((t_0 (* (fma -0.5 u 0.25) (PI))))
(*
(log (- 1.0 (/ (fma t_0 -4.0 (fma (/ (pow t_0 2.0) s) -8.0 (/ 0.0 s))) s)))
(- s))))\begin{array}{l}
\\
\begin{array}{l}
t_0 := \mathsf{fma}\left(-0.5, u, 0.25\right) \cdot \mathsf{PI}\left(\right)\\
\log \left(1 - \frac{\mathsf{fma}\left(t\_0, -4, \mathsf{fma}\left(\frac{{t\_0}^{2}}{s}, -8, \frac{0}{s}\right)\right)}{s}\right) \cdot \left(-s\right)
\end{array}
\end{array}
Initial program 99.1%
Taylor expanded in s around inf
distribute-rgt-out--N/A
metadata-evalN/A
associate-*r*N/A
metadata-evalN/A
distribute-rgt-neg-inN/A
associate-*r*N/A
metadata-evalN/A
distribute-rgt-out--N/A
distribute-neg-fracN/A
distribute-neg-frac2N/A
mul-1-negN/A
distribute-rgt-out--N/A
metadata-evalN/A
associate-*r*N/A
*-commutativeN/A
times-fracN/A
metadata-evalN/A
Applied rewrites3.1%
Taylor expanded in s around -inf
mul-1-negN/A
unsub-negN/A
lower--.f32N/A
Applied rewrites14.4%
Final simplification15.0%
(FPCore (u s)
:precision binary32
(if (<= s 1.9999999920083944e-12)
(*
(log
(-
(/
1.0
(fma -0.25 (/ (PI) s) (fma (/ (* (* (log (E)) (PI)) u) s) 0.5 0.5)))
1.0))
(- s))
(* (* (* (- (/ 0.25 u) 0.5) u) (PI)) -4.0)))\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;s \leq 1.9999999920083944 \cdot 10^{-12}:\\
\;\;\;\;\log \left(\frac{1}{\mathsf{fma}\left(-0.25, \frac{\mathsf{PI}\left(\right)}{s}, \mathsf{fma}\left(\frac{\left(\log \mathsf{E}\left(\right) \cdot \mathsf{PI}\left(\right)\right) \cdot u}{s}, 0.5, 0.5\right)\right)} - 1\right) \cdot \left(-s\right)\\
\mathbf{else}:\\
\;\;\;\;\left(\left(\left(\frac{0.25}{u} - 0.5\right) \cdot u\right) \cdot \mathsf{PI}\left(\right)\right) \cdot -4\\
\end{array}
\end{array}
if s < 1.99999999e-12Initial program 99.0%
Taylor expanded in s around inf
sub-negN/A
+-commutativeN/A
distribute-lft-neg-inN/A
metadata-evalN/A
lower-fma.f32N/A
lower-/.f32N/A
lower-PI.f32N/A
+-commutativeN/A
Applied rewrites12.3%
Applied rewrites14.1%
if 1.99999999e-12 < s Initial program 99.2%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f3218.1
Applied rewrites18.1%
Taylor expanded in s around -inf
*-commutativeN/A
lower-*.f32N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-out--N/A
metadata-evalN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
distribute-rgt-outN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-fma.f3218.1
Applied rewrites17.9%
Taylor expanded in u around inf
Applied rewrites18.3%
Final simplification15.2%
(FPCore (u s)
:precision binary32
(if (<= s 4.00000018325482e-18)
(fma
(fma -0.5 u 0.25)
(* -4.0 (PI))
(* (/ -0.5 s) (* (pow (* (fma -0.5 u 0.25) (PI)) 2.0) 0.0)))
(* (* (* (- (/ 0.25 u) 0.5) u) (PI)) -4.0)))\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;s \leq 4.00000018325482 \cdot 10^{-18}:\\
\;\;\;\;\mathsf{fma}\left(\mathsf{fma}\left(-0.5, u, 0.25\right), -4 \cdot \mathsf{PI}\left(\right), \frac{-0.5}{s} \cdot \left({\left(\mathsf{fma}\left(-0.5, u, 0.25\right) \cdot \mathsf{PI}\left(\right)\right)}^{2} \cdot 0\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\left(\left(\left(\frac{0.25}{u} - 0.5\right) \cdot u\right) \cdot \mathsf{PI}\left(\right)\right) \cdot -4\\
\end{array}
\end{array}
if s < 4.00000018e-18Initial program 99.0%
Taylor expanded in s around -inf
Applied rewrites3.2%
Applied rewrites6.6%
Applied rewrites7.6%
if 4.00000018e-18 < s Initial program 99.2%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f3216.3
Applied rewrites16.3%
Taylor expanded in s around -inf
*-commutativeN/A
lower-*.f32N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-out--N/A
metadata-evalN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
distribute-rgt-outN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-fma.f3216.3
Applied rewrites16.3%
Taylor expanded in u around inf
Applied rewrites16.5%
Final simplification10.4%
(FPCore (u s) :precision binary32 (if (<= s 2.1999999301841496e-20) (* (fma 2.0 (PI) 0.0) u) (* (* (* (- (/ 0.25 u) 0.5) u) (PI)) -4.0)))
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;s \leq 2.1999999301841496 \cdot 10^{-20}:\\
\;\;\;\;\mathsf{fma}\left(2, \mathsf{PI}\left(\right), 0\right) \cdot u\\
\mathbf{else}:\\
\;\;\;\;\left(\left(\left(\frac{0.25}{u} - 0.5\right) \cdot u\right) \cdot \mathsf{PI}\left(\right)\right) \cdot -4\\
\end{array}
\end{array}
if s < 2.19999993e-20Initial program 99.0%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f327.6
Applied rewrites7.6%
Taylor expanded in s around -inf
*-commutativeN/A
lower-*.f32N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-out--N/A
metadata-evalN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
distribute-rgt-outN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-fma.f327.6
Applied rewrites7.6%
Taylor expanded in u around inf
Applied rewrites5.7%
Applied rewrites13.3%
if 2.19999993e-20 < s Initial program 99.3%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f3215.5
Applied rewrites15.5%
Taylor expanded in s around -inf
*-commutativeN/A
lower-*.f32N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-out--N/A
metadata-evalN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
distribute-rgt-outN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-fma.f3215.5
Applied rewrites15.4%
Taylor expanded in u around inf
Applied rewrites15.6%
Final simplification14.3%
(FPCore (u s) :precision binary32 (if (<= s 2.1999999301841496e-20) (* (fma 2.0 (PI) 0.0) u) (* (+ (* 0.25 (PI)) (* (* (PI) u) -0.5)) -4.0)))
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;s \leq 2.1999999301841496 \cdot 10^{-20}:\\
\;\;\;\;\mathsf{fma}\left(2, \mathsf{PI}\left(\right), 0\right) \cdot u\\
\mathbf{else}:\\
\;\;\;\;\left(0.25 \cdot \mathsf{PI}\left(\right) + \left(\mathsf{PI}\left(\right) \cdot u\right) \cdot -0.5\right) \cdot -4\\
\end{array}
\end{array}
if s < 2.19999993e-20Initial program 99.0%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f327.6
Applied rewrites7.6%
Taylor expanded in s around -inf
*-commutativeN/A
lower-*.f32N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-out--N/A
metadata-evalN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
distribute-rgt-outN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-fma.f327.6
Applied rewrites7.6%
Taylor expanded in u around inf
Applied rewrites5.7%
Applied rewrites13.3%
if 2.19999993e-20 < s Initial program 99.3%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f3215.5
Applied rewrites15.5%
Taylor expanded in s around -inf
*-commutativeN/A
lower-*.f32N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-out--N/A
metadata-evalN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
distribute-rgt-outN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-fma.f3215.5
Applied rewrites15.4%
Applied rewrites15.6%
Final simplification14.3%
(FPCore (u s) :precision binary32 (if (<= s 2.1999999301841496e-20) (* (fma 2.0 (PI) 0.0) u) (* (* (+ (* -0.5 u) 0.25) (PI)) -4.0)))
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;s \leq 2.1999999301841496 \cdot 10^{-20}:\\
\;\;\;\;\mathsf{fma}\left(2, \mathsf{PI}\left(\right), 0\right) \cdot u\\
\mathbf{else}:\\
\;\;\;\;\left(\left(-0.5 \cdot u + 0.25\right) \cdot \mathsf{PI}\left(\right)\right) \cdot -4\\
\end{array}
\end{array}
if s < 2.19999993e-20Initial program 99.0%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f327.6
Applied rewrites7.6%
Taylor expanded in s around -inf
*-commutativeN/A
lower-*.f32N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-out--N/A
metadata-evalN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
distribute-rgt-outN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-fma.f327.6
Applied rewrites7.6%
Taylor expanded in u around inf
Applied rewrites5.7%
Applied rewrites13.3%
if 2.19999993e-20 < s Initial program 99.3%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f3215.5
Applied rewrites15.5%
Taylor expanded in s around -inf
*-commutativeN/A
lower-*.f32N/A
cancel-sign-sub-invN/A
metadata-evalN/A
distribute-rgt-out--N/A
metadata-evalN/A
*-commutativeN/A
associate-*r*N/A
*-commutativeN/A
distribute-rgt-outN/A
lower-*.f32N/A
lower-PI.f32N/A
lower-fma.f3215.5
Applied rewrites15.5%
Applied rewrites15.6%
Final simplification14.3%
(FPCore (u s) :precision binary32 (- (PI)))
\begin{array}{l}
\\
-\mathsf{PI}\left(\right)
\end{array}
Initial program 99.1%
Taylor expanded in u around 0
mul-1-negN/A
lower-neg.f32N/A
lower-PI.f3211.0
Applied rewrites11.0%
herbie shell --seed 2024296
(FPCore (u s)
:name "Sample trimmed logistic on [-pi, pi]"
:precision binary32
:pre (and (and (<= 2.328306437e-10 u) (<= u 1.0)) (and (<= 0.0 s) (<= s 1.0651631)))
(* (- s) (log (- (/ 1.0 (+ (* u (- (/ 1.0 (+ 1.0 (exp (/ (- (PI)) s)))) (/ 1.0 (+ 1.0 (exp (/ (PI) s)))))) (/ 1.0 (+ 1.0 (exp (/ (PI) s)))))) 1.0))))