
(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 5 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 (/ (pow (* (sqrt 2.0) (PI)) -1.0) t))
\begin{array}{l}
\\
\frac{{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right)}^{-1}}{t}
\end{array}
Initial program 99.3%
Taylor expanded in v around 0
inv-powN/A
lower-pow.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lift-PI.f6499.4
Applied rewrites99.4%
lift-pow.f64N/A
lift-*.f64N/A
unpow-prod-downN/A
lower-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
*-commutativeN/A
lower-pow.f64N/A
*-commutativeN/A
lift-sqrt.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lower-pow.f6499.5
Applied rewrites99.5%
lift-pow.f64N/A
inv-powN/A
lower-/.f6499.5
Applied rewrites99.5%
lift-*.f64N/A
lift-/.f64N/A
associate-*r/N/A
lower-/.f64N/A
lower-*.f6499.8
Applied rewrites99.8%
Final simplification99.8%
(FPCore (v t) :precision binary64 (* (/ 1.0 (* (sqrt 2.0) (PI))) (/ 1.0 t)))
\begin{array}{l}
\\
\frac{1}{\sqrt{2} \cdot \mathsf{PI}\left(\right)} \cdot \frac{1}{t}
\end{array}
Initial program 99.3%
Taylor expanded in v around 0
inv-powN/A
lower-pow.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lift-PI.f6499.4
Applied rewrites99.4%
lift-pow.f64N/A
lift-*.f64N/A
unpow-prod-downN/A
lower-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
*-commutativeN/A
lower-pow.f64N/A
*-commutativeN/A
lift-sqrt.f64N/A
lift-*.f64N/A
lift-PI.f64N/A
lower-pow.f6499.5
Applied rewrites99.5%
lift-pow.f64N/A
inv-powN/A
lower-/.f6499.5
Applied rewrites99.5%
lift-pow.f64N/A
unpow-1N/A
lift-PI.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
*-commutativeN/A
lower-/.f64N/A
*-commutativeN/A
lift-sqrt.f64N/A
lift-*.f64N/A
lift-PI.f6499.5
Applied rewrites99.5%
(FPCore (v t) :precision binary64 (/ (/ 1.0 t) (* (sqrt 2.0) (PI))))
\begin{array}{l}
\\
\frac{\frac{1}{t}}{\sqrt{2} \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 99.3%
Taylor expanded in v around 0
inv-powN/A
lower-pow.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lift-PI.f6499.4
Applied rewrites99.4%
lift-pow.f64N/A
unpow-1N/A
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
*-commutativeN/A
*-commutativeN/A
associate-/r*N/A
lower-/.f64N/A
lower-/.f64N/A
*-commutativeN/A
lift-sqrt.f64N/A
lift-*.f64N/A
lift-PI.f6499.5
Applied rewrites99.5%
(FPCore (v t) :precision binary64 (/ 1.0 (* (* (sqrt 2.0) (PI)) t)))
\begin{array}{l}
\\
\frac{1}{\left(\sqrt{2} \cdot \mathsf{PI}\left(\right)\right) \cdot t}
\end{array}
Initial program 99.3%
Taylor expanded in v around 0
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lift-PI.f6499.4
Applied rewrites99.4%
Taylor expanded in v around 0
Applied rewrites99.4%
(FPCore (v t) :precision binary64 (/ 1.0 (* (* t (PI)) (sqrt 2.0))))
\begin{array}{l}
\\
\frac{1}{\left(t \cdot \mathsf{PI}\left(\right)\right) \cdot \sqrt{2}}
\end{array}
Initial program 99.3%
Taylor expanded in v around 0
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lift-PI.f6499.4
Applied rewrites99.4%
Taylor expanded in v around 0
Applied rewrites99.4%
lift-*.f64N/A
lift-PI.f64N/A
lift-*.f64N/A
lift-sqrt.f64N/A
associate-*l*N/A
*-commutativeN/A
*-commutativeN/A
lift-*.f64N/A
lift-PI.f64N/A
lift-sqrt.f64N/A
lift-*.f6499.3
Applied rewrites99.3%
herbie shell --seed 2025037
(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)))))