
(FPCore (v) :precision binary64 (/ 4.0 (* (* (* 3.0 (PI)) (- 1.0 (* v v))) (sqrt (- 2.0 (* 6.0 (* v v)))))))
\begin{array}{l}
\\
\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 8 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (v) :precision binary64 (/ 4.0 (* (* (* 3.0 (PI)) (- 1.0 (* v v))) (sqrt (- 2.0 (* 6.0 (* v v)))))))
\begin{array}{l}
\\
\frac{4}{\left(\left(3 \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}
\end{array}
(FPCore (v) :precision binary64 (* (fma v v 1.0) (/ (/ 1.3333333333333333 (PI)) (* (sqrt (fma -6.0 (* v v) 2.0)) (- 1.0 (pow v 4.0))))))
\begin{array}{l}
\\
\mathsf{fma}\left(v, v, 1\right) \cdot \frac{\frac{1.3333333333333333}{\mathsf{PI}\left(\right)}}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(1 - {v}^{4}\right)}
\end{array}
Initial program 98.5%
lift-/.f64N/A
lift-*.f64N/A
lift-*.f64N/A
associate-*l*N/A
associate-/r*N/A
lift--.f64N/A
flip--N/A
associate-*l/N/A
associate-/r/N/A
lower-*.f64N/A
Applied rewrites100.0%
Final simplification100.0%
(FPCore (v) :precision binary64 (/ 4.0 (* (* (- 1.0 (* v v)) (PI)) (* 3.0 (sqrt (fma (* v v) -6.0 2.0))))))
\begin{array}{l}
\\
\frac{4}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \left(3 \cdot \sqrt{\mathsf{fma}\left(v \cdot v, -6, 2\right)}\right)}
\end{array}
Initial program 98.5%
lift-*.f64N/A
lift--.f64N/A
sub-negN/A
+-commutativeN/A
distribute-lft-inN/A
*-commutativeN/A
lift-*.f64N/A
associate-*r*N/A
*-rgt-identityN/A
lower-fma.f64N/A
lower-*.f64N/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-*.f64N/A
lower-neg.f6498.5
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.5
Applied rewrites98.5%
lift-*.f64N/A
*-commutativeN/A
lift-fma.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lift-*.f64N/A
distribute-lft1-inN/A
+-commutativeN/A
lift-*.f64N/A
lift-neg.f64N/A
cancel-sign-sub-invN/A
lift-*.f64N/A
*-commutativeN/A
lift-PI.f64N/A
*-commutativeN/A
Applied rewrites100.0%
Final simplification100.0%
(FPCore (v) :precision binary64 (/ 1.3333333333333333 (* (* (- 1.0 (* v v)) (sqrt (fma (* v v) -6.0 2.0))) (PI))))
\begin{array}{l}
\\
\frac{1.3333333333333333}{\left(\left(1 - v \cdot v\right) \cdot \sqrt{\mathsf{fma}\left(v \cdot v, -6, 2\right)}\right) \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.5%
lift-*.f64N/A
lift--.f64N/A
sub-negN/A
+-commutativeN/A
distribute-lft-inN/A
*-commutativeN/A
lift-*.f64N/A
associate-*r*N/A
*-rgt-identityN/A
lower-fma.f64N/A
lower-*.f64N/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-*.f64N/A
lower-neg.f6498.5
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.5
Applied rewrites98.5%
lift-*.f64N/A
*-commutativeN/A
lift-fma.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lift-*.f64N/A
distribute-lft1-inN/A
+-commutativeN/A
lift-*.f64N/A
lift-neg.f64N/A
cancel-sign-sub-invN/A
lift-*.f64N/A
*-commutativeN/A
lift-PI.f64N/A
*-commutativeN/A
Applied rewrites100.0%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
div-invN/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
metadata-evalN/A
frac-timesN/A
metadata-evalN/A
lower-/.f64N/A
lower-*.f64100.0
Applied rewrites100.0%
lift-*.f64N/A
*-commutativeN/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lower-*.f64N/A
lower-*.f64100.0
lift-fma.f64N/A
*-commutativeN/A
lift-fma.f64100.0
Applied rewrites100.0%
(FPCore (v) :precision binary64 (/ 1.3333333333333333 (* (* (- 1.0 (* v v)) (PI)) (sqrt (fma -6.0 (* v v) 2.0)))))
\begin{array}{l}
\\
\frac{1.3333333333333333}{\left(\left(1 - v \cdot v\right) \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}
\end{array}
Initial program 98.5%
lift-*.f64N/A
lift--.f64N/A
sub-negN/A
+-commutativeN/A
distribute-lft-inN/A
*-commutativeN/A
lift-*.f64N/A
associate-*r*N/A
*-rgt-identityN/A
lower-fma.f64N/A
lower-*.f64N/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-*.f64N/A
lower-neg.f6498.5
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.5
Applied rewrites98.5%
lift-*.f64N/A
*-commutativeN/A
lift-fma.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lift-*.f64N/A
distribute-lft1-inN/A
+-commutativeN/A
lift-*.f64N/A
lift-neg.f64N/A
cancel-sign-sub-invN/A
lift-*.f64N/A
*-commutativeN/A
lift-PI.f64N/A
*-commutativeN/A
Applied rewrites100.0%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
div-invN/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
metadata-evalN/A
frac-timesN/A
metadata-evalN/A
lower-/.f64N/A
lower-*.f64100.0
Applied rewrites100.0%
Final simplification100.0%
(FPCore (v) :precision binary64 (/ 4.0 (* (PI) (* 3.0 (sqrt (fma (* v v) -6.0 2.0))))))
\begin{array}{l}
\\
\frac{4}{\mathsf{PI}\left(\right) \cdot \left(3 \cdot \sqrt{\mathsf{fma}\left(v \cdot v, -6, 2\right)}\right)}
\end{array}
Initial program 98.5%
lift-*.f64N/A
lift--.f64N/A
sub-negN/A
+-commutativeN/A
distribute-lft-inN/A
*-commutativeN/A
lift-*.f64N/A
associate-*r*N/A
*-rgt-identityN/A
lower-fma.f64N/A
lower-*.f64N/A
lift-*.f64N/A
distribute-lft-neg-inN/A
lower-*.f64N/A
lower-neg.f6498.5
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.5
Applied rewrites98.5%
lift-*.f64N/A
*-commutativeN/A
lift-fma.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lift-*.f64N/A
distribute-lft1-inN/A
+-commutativeN/A
lift-*.f64N/A
lift-neg.f64N/A
cancel-sign-sub-invN/A
lift-*.f64N/A
*-commutativeN/A
lift-PI.f64N/A
*-commutativeN/A
Applied rewrites100.0%
Taylor expanded in v around 0
lower-PI.f6498.6
Applied rewrites98.6%
Final simplification98.6%
(FPCore (v) :precision binary64 (/ 1.3333333333333333 (* (PI) (sqrt (fma -6.0 (* v v) 2.0)))))
\begin{array}{l}
\\
\frac{1.3333333333333333}{\mathsf{PI}\left(\right) \cdot \sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}
\end{array}
Initial program 98.5%
Applied rewrites98.6%
Taylor expanded in v around 0
lower-PI.f6498.6
Applied rewrites98.6%
(FPCore (v) :precision binary64 (/ 1.3333333333333333 (* (sqrt 2.0) (PI))))
\begin{array}{l}
\\
\frac{1.3333333333333333}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 98.5%
Applied rewrites98.6%
Taylor expanded in v around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6498.6
Applied rewrites98.6%
(FPCore (v) :precision binary64 (* (/ (sqrt 0.5) (PI)) 1.3333333333333333))
\begin{array}{l}
\\
\frac{\sqrt{0.5}}{\mathsf{PI}\left(\right)} \cdot 1.3333333333333333
\end{array}
Initial program 98.5%
Taylor expanded in v around 0
*-commutativeN/A
lower-*.f64N/A
lower-/.f64N/A
lower-sqrt.f64N/A
lower-PI.f6497.1
Applied rewrites97.1%
herbie shell --seed 2024249
(FPCore (v)
:name "Falkner and Boettcher, Equation (22+)"
:precision binary64
(/ 4.0 (* (* (* 3.0 (PI)) (- 1.0 (* v v))) (sqrt (- 2.0 (* 6.0 (* v v)))))))