
(FPCore (v t) :precision binary64 (/ (- 1.0 (* 5.0 (* v v))) (* (* (* (PI) t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))
\begin{array}{l}
\\
\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 9 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (v t) :precision binary64 (/ (- 1.0 (* 5.0 (* v v))) (* (* (* (PI) t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))
\begin{array}{l}
\\
\frac{1 - 5 \cdot \left(v \cdot v\right)}{\left(\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{2 \cdot \left(1 - 3 \cdot \left(v \cdot v\right)\right)}\right) \cdot \left(1 - v \cdot v\right)}
\end{array}
(FPCore (v t) :precision binary64 (/ (/ (fma -5.0 (* v v) 1.0) (PI)) (* (* t (- 1.0 (* v v))) (sqrt (fma -6.0 (* v v) 2.0)))))
\begin{array}{l}
\\
\frac{\frac{\mathsf{fma}\left(-5, v \cdot v, 1\right)}{\mathsf{PI}\left(\right)}}{\left(t \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}
\end{array}
Initial program 98.7%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
div-invN/A
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
associate-/r*N/A
frac-timesN/A
Applied rewrites99.5%
Final simplification99.5%
(FPCore (v t) :precision binary64 (* (/ (fma -5.0 (* v v) 1.0) t) (pow (* (sqrt 2.0) (PI)) -1.0)))
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(-5, v \cdot v, 1\right)}{t} \cdot {\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right)}^{-1}
\end{array}
Initial program 98.7%
lift-/.f64N/A
*-rgt-identityN/A
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
lift-*.f64N/A
*-commutativeN/A
associate-*l*N/A
times-fracN/A
lower-*.f64N/A
Applied rewrites99.4%
Taylor expanded in v around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6498.5
Applied rewrites98.5%
Final simplification98.5%
(FPCore (v t) :precision binary64 (pow (* (* (sqrt 2.0) (PI)) t) -1.0))
\begin{array}{l}
\\
{\left(\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t\right)}^{-1}
\end{array}
Initial program 98.7%
Taylor expanded in v around 0
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6498.0
Applied rewrites98.0%
Final simplification98.0%
(FPCore (v t) :precision binary64 (/ (/ (/ (fma (fma -4.0 (* v v) -4.0) (* v v) 1.0) (sqrt (fma -6.0 (* v v) 2.0))) (PI)) t))
\begin{array}{l}
\\
\frac{\frac{\frac{\mathsf{fma}\left(\mathsf{fma}\left(-4, v \cdot v, -4\right), v \cdot v, 1\right)}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}}{\mathsf{PI}\left(\right)}}{t}
\end{array}
Initial program 98.7%
lift-/.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
lower-/.f64N/A
lower-/.f6498.7
lift--.f64N/A
sub-negN/A
+-commutativeN/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
metadata-eval98.7
Applied rewrites98.7%
Taylor expanded in v around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
sub-negN/A
metadata-evalN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6498.4
Applied rewrites98.4%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
lower-/.f64N/A
Applied rewrites99.5%
(FPCore (v t) :precision binary64 (/ (/ (fma -4.0 (* v v) 1.0) (* (PI) (sqrt (fma -6.0 (* v v) 2.0)))) t))
\begin{array}{l}
\\
\frac{\frac{\mathsf{fma}\left(-4, v \cdot v, 1\right)}{\mathsf{PI}\left(\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}}{t}
\end{array}
Initial program 98.7%
lift-/.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
lower-/.f64N/A
lower-/.f6498.7
lift--.f64N/A
sub-negN/A
+-commutativeN/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
metadata-eval98.7
Applied rewrites98.7%
Taylor expanded in v around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
sub-negN/A
metadata-evalN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6498.4
Applied rewrites98.4%
Taylor expanded in v around 0
Applied rewrites98.3%
lift-/.f64N/A
lift-*.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-*l*N/A
lift-*.f64N/A
associate-/r*N/A
lower-/.f64N/A
Applied rewrites99.3%
(FPCore (v t) :precision binary64 (/ (/ (/ 1.0 (sqrt (fma -6.0 (* v v) 2.0))) (PI)) t))
\begin{array}{l}
\\
\frac{\frac{\frac{1}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}}{\mathsf{PI}\left(\right)}}{t}
\end{array}
Initial program 98.7%
lift-/.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
lower-/.f64N/A
lower-/.f6498.7
lift--.f64N/A
sub-negN/A
+-commutativeN/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-fma.f64N/A
metadata-eval98.7
Applied rewrites98.7%
Taylor expanded in v around 0
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
sub-negN/A
metadata-evalN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f64N/A
unpow2N/A
lower-*.f6498.4
Applied rewrites98.4%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
lower-/.f64N/A
Applied rewrites99.5%
Taylor expanded in v around 0
Applied rewrites98.8%
(FPCore (v t) :precision binary64 (/ (/ (fma -5.0 (* v v) 1.0) (PI)) (* (sqrt 2.0) t)))
\begin{array}{l}
\\
\frac{\frac{\mathsf{fma}\left(-5, v \cdot v, 1\right)}{\mathsf{PI}\left(\right)}}{\sqrt{2} \cdot t}
\end{array}
Initial program 98.7%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
div-invN/A
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
associate-/r*N/A
frac-timesN/A
Applied rewrites99.5%
Taylor expanded in v around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f6498.6
Applied rewrites98.6%
Final simplification98.6%
(FPCore (v t) :precision binary64 (/ (/ (sqrt 0.5) t) (PI)))
\begin{array}{l}
\\
\frac{\frac{\sqrt{0.5}}{t}}{\mathsf{PI}\left(\right)}
\end{array}
Initial program 98.7%
lift-/.f64N/A
*-rgt-identityN/A
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
lift-*.f64N/A
*-commutativeN/A
associate-*l*N/A
times-fracN/A
lower-*.f64N/A
Applied rewrites99.4%
Taylor expanded in v around 0
associate-/r*N/A
lower-/.f64N/A
lower-/.f64N/A
lower-sqrt.f64N/A
lower-PI.f6498.1
Applied rewrites98.1%
(FPCore (v t) :precision binary64 (/ (sqrt 0.5) (* (PI) t)))
\begin{array}{l}
\\
\frac{\sqrt{0.5}}{\mathsf{PI}\left(\right) \cdot t}
\end{array}
Initial program 98.7%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
div-invN/A
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
associate-/r*N/A
frac-timesN/A
Applied rewrites99.5%
Applied rewrites98.0%
Taylor expanded in v around 0
lower-sqrt.f6497.8
Applied rewrites97.8%
Taylor expanded in v around 0
lower-PI.f6497.8
Applied rewrites97.8%
herbie shell --seed 2024302
(FPCore (v t)
:name "Falkner and Boettcher, Equation (20:1,3)"
:precision binary64
(/ (- 1.0 (* 5.0 (* v v))) (* (* (* (PI) t) (sqrt (* 2.0 (- 1.0 (* 3.0 (* v v)))))) (- 1.0 (* v v)))))