
(FPCore (v) :precision binary64 (/ 4.0 (* (* (* 3.0 PI) (- 1.0 (* v v))) (sqrt (- 2.0 (* 6.0 (* v v)))))))
double code(double v) {
return 4.0 / (((3.0 * ((double) M_PI)) * (1.0 - (v * v))) * sqrt((2.0 - (6.0 * (v * v)))));
}
public static double code(double v) {
return 4.0 / (((3.0 * Math.PI) * (1.0 - (v * v))) * Math.sqrt((2.0 - (6.0 * (v * v)))));
}
def code(v): return 4.0 / (((3.0 * math.pi) * (1.0 - (v * v))) * math.sqrt((2.0 - (6.0 * (v * v)))))
function code(v) return Float64(4.0 / Float64(Float64(Float64(3.0 * pi) * Float64(1.0 - Float64(v * v))) * sqrt(Float64(2.0 - Float64(6.0 * Float64(v * v)))))) end
function tmp = code(v) tmp = 4.0 / (((3.0 * pi) * (1.0 - (v * v))) * sqrt((2.0 - (6.0 * (v * v))))); end
code[v_] := N[(4.0 / N[(N[(N[(3.0 * Pi), $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(2.0 - N[(6.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{4}{\left(\left(3 \cdot \pi\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 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (v) :precision binary64 (/ 4.0 (* (* (* 3.0 PI) (- 1.0 (* v v))) (sqrt (- 2.0 (* 6.0 (* v v)))))))
double code(double v) {
return 4.0 / (((3.0 * ((double) M_PI)) * (1.0 - (v * v))) * sqrt((2.0 - (6.0 * (v * v)))));
}
public static double code(double v) {
return 4.0 / (((3.0 * Math.PI) * (1.0 - (v * v))) * Math.sqrt((2.0 - (6.0 * (v * v)))));
}
def code(v): return 4.0 / (((3.0 * math.pi) * (1.0 - (v * v))) * math.sqrt((2.0 - (6.0 * (v * v)))))
function code(v) return Float64(4.0 / Float64(Float64(Float64(3.0 * pi) * Float64(1.0 - Float64(v * v))) * sqrt(Float64(2.0 - Float64(6.0 * Float64(v * v)))))) end
function tmp = code(v) tmp = 4.0 / (((3.0 * pi) * (1.0 - (v * v))) * sqrt((2.0 - (6.0 * (v * v))))); end
code[v_] := N[(4.0 / N[(N[(N[(3.0 * Pi), $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(2.0 - N[(6.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{4}{\left(\left(3 \cdot \pi\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 (* (/ (/ 1.3333333333333333 PI) (* (sqrt (fma v (* v -6.0) 2.0)) (- 1.0 (* v (* v (* v v)))))) (fma v v 1.0)))
double code(double v) {
return ((1.3333333333333333 / ((double) M_PI)) / (sqrt(fma(v, (v * -6.0), 2.0)) * (1.0 - (v * (v * (v * v)))))) * fma(v, v, 1.0);
}
function code(v) return Float64(Float64(Float64(1.3333333333333333 / pi) / Float64(sqrt(fma(v, Float64(v * -6.0), 2.0)) * Float64(1.0 - Float64(v * Float64(v * Float64(v * v)))))) * fma(v, v, 1.0)) end
code[v_] := N[(N[(N[(1.3333333333333333 / Pi), $MachinePrecision] / N[(N[Sqrt[N[(v * N[(v * -6.0), $MachinePrecision] + 2.0), $MachinePrecision]], $MachinePrecision] * N[(1.0 - N[(v * N[(v * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(v * v + 1.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{1.3333333333333333}{\pi}}{\sqrt{\mathsf{fma}\left(v, v \cdot -6, 2\right)} \cdot \left(1 - v \cdot \left(v \cdot \left(v \cdot v\right)\right)\right)} \cdot \mathsf{fma}\left(v, v, 1\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%
(FPCore (v) :precision binary64 (/ (/ 4.0 (sqrt (fma v (* v -6.0) 2.0))) (* PI (fma v (* v -3.0) 3.0))))
double code(double v) {
return (4.0 / sqrt(fma(v, (v * -6.0), 2.0))) / (((double) M_PI) * fma(v, (v * -3.0), 3.0));
}
function code(v) return Float64(Float64(4.0 / sqrt(fma(v, Float64(v * -6.0), 2.0))) / Float64(pi * fma(v, Float64(v * -3.0), 3.0))) end
code[v_] := N[(N[(4.0 / N[Sqrt[N[(v * N[(v * -6.0), $MachinePrecision] + 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(Pi * N[(v * N[(v * -3.0), $MachinePrecision] + 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{4}{\sqrt{\mathsf{fma}\left(v, v \cdot -6, 2\right)}}}{\pi \cdot \mathsf{fma}\left(v, v \cdot -3, 3\right)}
\end{array}
Initial program 98.5%
Taylor expanded in v around 0
+-commutativeN/A
associate-*r*N/A
distribute-rgt-outN/A
lower-*.f64N/A
lower-PI.f64N/A
+-commutativeN/A
*-commutativeN/A
lower-fma.f64N/A
unpow2N/A
lower-*.f6498.5
Applied rewrites98.5%
lift-/.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-/r*N/A
lower-/.f64N/A
Applied rewrites100.0%
(FPCore (v) :precision binary64 (/ 1.3333333333333333 (* PI (* (sqrt (fma -6.0 (* v v) 2.0)) (- 1.0 (* v v))))))
double code(double v) {
return 1.3333333333333333 / (((double) M_PI) * (sqrt(fma(-6.0, (v * v), 2.0)) * (1.0 - (v * v))));
}
function code(v) return Float64(1.3333333333333333 / Float64(pi * Float64(sqrt(fma(-6.0, Float64(v * v), 2.0)) * Float64(1.0 - Float64(v * v))))) end
code[v_] := N[(1.3333333333333333 / N[(Pi * N[(N[Sqrt[N[(-6.0 * N[(v * v), $MachinePrecision] + 2.0), $MachinePrecision]], $MachinePrecision] * N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1.3333333333333333}{\pi \cdot \left(\sqrt{\mathsf{fma}\left(-6, v \cdot v, 2\right)} \cdot \left(1 - v \cdot v\right)\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%
Applied rewrites100.0%
lift-/.f64N/A
lift-*.f64N/A
lift-/.f64N/A
associate-*r/N/A
associate-/r/N/A
lift-/.f64N/A
frac-timesN/A
metadata-evalN/A
lower-/.f64N/A
lower-*.f64N/A
Applied rewrites100.0%
Final simplification100.0%
(FPCore (v) :precision binary64 (/ (/ 4.0 (* PI 3.0)) (sqrt (fma v (* v -6.0) 2.0))))
double code(double v) {
return (4.0 / (((double) M_PI) * 3.0)) / sqrt(fma(v, (v * -6.0), 2.0));
}
function code(v) return Float64(Float64(4.0 / Float64(pi * 3.0)) / sqrt(fma(v, Float64(v * -6.0), 2.0))) end
code[v_] := N[(N[(4.0 / N[(Pi * 3.0), $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(v * N[(v * -6.0), $MachinePrecision] + 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{4}{\pi \cdot 3}}{\sqrt{\mathsf{fma}\left(v, v \cdot -6, 2\right)}}
\end{array}
Initial program 98.5%
Taylor expanded in v around 0
*-commutativeN/A
lower-*.f64N/A
lower-PI.f6496.6
Applied rewrites96.6%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
lower-/.f64N/A
lower-/.f6498.1
lift--.f64N/A
sub-negN/A
lift-*.f64N/A
*-commutativeN/A
distribute-rgt-neg-inN/A
lift-*.f64N/A
metadata-evalN/A
associate-*r*N/A
lift-*.f64N/A
+-commutativeN/A
lift-fma.f6498.1
Applied rewrites98.1%
(FPCore (v) :precision binary64 (/ 1.3333333333333333 (* PI (* (- 1.0 (* v v)) (sqrt 2.0)))))
double code(double v) {
return 1.3333333333333333 / (((double) M_PI) * ((1.0 - (v * v)) * sqrt(2.0)));
}
public static double code(double v) {
return 1.3333333333333333 / (Math.PI * ((1.0 - (v * v)) * Math.sqrt(2.0)));
}
def code(v): return 1.3333333333333333 / (math.pi * ((1.0 - (v * v)) * math.sqrt(2.0)))
function code(v) return Float64(1.3333333333333333 / Float64(pi * Float64(Float64(1.0 - Float64(v * v)) * sqrt(2.0)))) end
function tmp = code(v) tmp = 1.3333333333333333 / (pi * ((1.0 - (v * v)) * sqrt(2.0))); end
code[v_] := N[(1.3333333333333333 / N[(Pi * N[(N[(1.0 - N[(v * v), $MachinePrecision]), $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1.3333333333333333}{\pi \cdot \left(\left(1 - v \cdot v\right) \cdot \sqrt{2}\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%
Applied rewrites100.0%
lift-/.f64N/A
lift-*.f64N/A
lift-/.f64N/A
associate-*r/N/A
associate-/r/N/A
lift-/.f64N/A
frac-timesN/A
metadata-evalN/A
lower-/.f64N/A
lower-*.f64N/A
Applied rewrites100.0%
Taylor expanded in v around 0
lower-sqrt.f6498.1
Applied rewrites98.1%
Final simplification98.1%
(FPCore (v) :precision binary64 (* (/ 1.3333333333333333 PI) (sqrt 0.5)))
double code(double v) {
return (1.3333333333333333 / ((double) M_PI)) * sqrt(0.5);
}
public static double code(double v) {
return (1.3333333333333333 / Math.PI) * Math.sqrt(0.5);
}
def code(v): return (1.3333333333333333 / math.pi) * math.sqrt(0.5)
function code(v) return Float64(Float64(1.3333333333333333 / pi) * sqrt(0.5)) end
function tmp = code(v) tmp = (1.3333333333333333 / pi) * sqrt(0.5); end
code[v_] := N[(N[(1.3333333333333333 / Pi), $MachinePrecision] * N[Sqrt[0.5], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1.3333333333333333}{\pi} \cdot \sqrt{0.5}
\end{array}
Initial program 98.5%
Taylor expanded in v around 0
associate-*r/N/A
lower-/.f64N/A
lower-*.f64N/A
lower-sqrt.f64N/A
lower-PI.f6496.6
Applied rewrites96.6%
Applied rewrites98.0%
Final simplification98.0%
herbie shell --seed 2024232
(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)))))))