
(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) (- 1.0 (* v v)))) (sqrt (fma -6.0 (* v v) 2.0))) t))
\begin{array}{l}
\\
\frac{\frac{\frac{\mathsf{fma}\left(-5, v \cdot v, 1\right)}{\mathsf{PI}\left(\right) \cdot \left(1 - v \cdot v\right)}}{\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)}}}{t}
\end{array}
Initial program 99.3%
Taylor expanded in t around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
lower--.f64N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
associate-/r*N/A
lower-/.f64N/A
Applied rewrites99.5%
Applied rewrites99.5%
Applied rewrites99.9%
Applied rewrites99.9%
Final simplification99.9%
(FPCore (v t) :precision binary64 (/ (- -1.0 (* (* v v) -5.0)) (* (* (* (sqrt (fma -6.0 (* v v) 2.0)) (PI)) t) (- (* v v) 1.0))))
\begin{array}{l}
\\
\frac{-1 - \left(v \cdot v\right) \cdot -5}{\left(\left(\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \mathsf{PI}\left(\right)\right) \cdot t\right) \cdot \left(v \cdot v - 1\right)}
\end{array}
Initial program 99.3%
Taylor expanded in t around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower--.f64N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6499.6
Applied rewrites99.6%
Applied rewrites99.4%
Applied rewrites99.6%
Final simplification99.6%
(FPCore (v t) :precision binary64 (/ (fma (* v v) -5.0 1.0) (* (* (* (sqrt (fma -6.0 (* v v) 2.0)) (PI)) (- 1.0 (* v v))) t)))
\begin{array}{l}
\\
\frac{\mathsf{fma}\left(v \cdot v, -5, 1\right)}{\left(\left(\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \mathsf{PI}\left(\right)\right) \cdot \left(1 - v \cdot v\right)\right) \cdot t}
\end{array}
Initial program 99.3%
Taylor expanded in t around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
lower--.f64N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
associate-/r*N/A
lower-/.f64N/A
Applied rewrites99.5%
Applied rewrites99.5%
Applied rewrites99.6%
Applied rewrites99.6%
Final simplification99.6%
(FPCore (v t) :precision binary64 (/ (- (* (* (/ (* v v) t) -2.5) t) -1.0) (* (* (sqrt 2.0) (PI)) t)))
\begin{array}{l}
\\
\frac{\left(\frac{v \cdot v}{t} \cdot -2.5\right) \cdot t - -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-fma.f64N/A
associate-/r*N/A
lower-/.f64N/A
lower-/.f64N/A
unpow2N/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6499.1
Applied rewrites99.1%
Applied rewrites99.1%
Final simplification99.1%
(FPCore (v t) :precision binary64 (/ (* (/ 1.0 (* (sqrt 2.0) (PI))) (fma (* v v) -5.0 1.0)) t))
\begin{array}{l}
\\
\frac{\frac{1}{\sqrt{2} \cdot \mathsf{PI}\left(\right)} \cdot \mathsf{fma}\left(v \cdot v, -5, 1\right)}{t}
\end{array}
Initial program 99.3%
Taylor expanded in t around 0
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-/.f64N/A
lower--.f64N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
associate-/r*N/A
lower-/.f64N/A
Applied rewrites99.5%
Applied rewrites99.5%
Applied rewrites99.9%
Taylor expanded in v around 0
Applied rewrites98.5%
Final simplification98.5%
(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
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6498.2
Applied rewrites98.2%
(FPCore (v t) :precision binary64 (/ 1.0 (* (* (sqrt 2.0) t) (PI))))
\begin{array}{l}
\\
\frac{1}{\left(\sqrt{2} \cdot t\right) \cdot \mathsf{PI}\left(\right)}
\end{array}
Initial program 99.3%
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.f6498.2
Applied rewrites98.2%
Applied rewrites98.1%
Final simplification98.1%
(FPCore (v t) :precision binary64 (/ 1.0 (* (* (PI) t) (sqrt 2.0))))
\begin{array}{l}
\\
\frac{1}{\left(\mathsf{PI}\left(\right) \cdot t\right) \cdot \sqrt{2}}
\end{array}
Initial program 99.3%
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.f6498.2
Applied rewrites98.2%
Applied rewrites98.0%
Final simplification98.0%
(FPCore (v t) :precision binary64 0.0)
double code(double v, double t) {
return 0.0;
}
real(8) function code(v, t)
real(8), intent (in) :: v
real(8), intent (in) :: t
code = 0.0d0
end function
public static double code(double v, double t) {
return 0.0;
}
def code(v, t): return 0.0
function code(v, t) return 0.0 end
function tmp = code(v, t) tmp = 0.0; end
code[v_, t_] := 0.0
\begin{array}{l}
\\
0
\end{array}
Initial program 99.3%
Applied rewrites3.8%
Taylor expanded in v around 0
Applied rewrites3.8%
herbie shell --seed 2024312
(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)))))