
(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}
Herbie found 4 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
(let* ((t_0 (/ PI (sqrt 2.0))) (t_1 (* PI (sqrt 2.0))))
(/
4.0
(fma
3.0
t_1
(*
(pow v 2.0)
(fma
3.0
(* (pow v 2.0) (fma -4.5 (/ PI (pow (sqrt 2.0) 3.0)) (* 3.0 t_0)))
(* 3.0 (fma -3.0 t_0 (* -1.0 t_1)))))))))
double code(double v) {
double t_0 = ((double) M_PI) / sqrt(2.0);
double t_1 = ((double) M_PI) * sqrt(2.0);
return 4.0 / fma(3.0, t_1, (pow(v, 2.0) * fma(3.0, (pow(v, 2.0) * fma(-4.5, (((double) M_PI) / pow(sqrt(2.0), 3.0)), (3.0 * t_0))), (3.0 * fma(-3.0, t_0, (-1.0 * t_1))))));
}
function code(v) t_0 = Float64(pi / sqrt(2.0)) t_1 = Float64(pi * sqrt(2.0)) return Float64(4.0 / fma(3.0, t_1, Float64((v ^ 2.0) * fma(3.0, Float64((v ^ 2.0) * fma(-4.5, Float64(pi / (sqrt(2.0) ^ 3.0)), Float64(3.0 * t_0))), Float64(3.0 * fma(-3.0, t_0, Float64(-1.0 * t_1))))))) end
code[v_] := Block[{t$95$0 = N[(Pi / N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(Pi * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]}, N[(4.0 / N[(3.0 * t$95$1 + N[(N[Power[v, 2.0], $MachinePrecision] * N[(3.0 * N[(N[Power[v, 2.0], $MachinePrecision] * N[(-4.5 * N[(Pi / N[Power[N[Sqrt[2.0], $MachinePrecision], 3.0], $MachinePrecision]), $MachinePrecision] + N[(3.0 * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(3.0 * N[(-3.0 * t$95$0 + N[(-1.0 * t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{\pi}{\sqrt{2}}\\
t_1 := \pi \cdot \sqrt{2}\\
\frac{4}{\mathsf{fma}\left(3, t\_1, {v}^{2} \cdot \mathsf{fma}\left(3, {v}^{2} \cdot \mathsf{fma}\left(-4.5, \frac{\pi}{{\left(\sqrt{2}\right)}^{3}}, 3 \cdot t\_0\right), 3 \cdot \mathsf{fma}\left(-3, t\_0, -1 \cdot t\_1\right)\right)\right)}
\end{array}
\end{array}
Initial program 98.5%
Taylor expanded in v around 0
lower-fma.f64N/A
lower-*.f64N/A
lift-PI.f64N/A
lower-sqrt.f64N/A
lower-*.f64N/A
Applied rewrites98.1%
(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}
Initial program 98.5%
(FPCore (v) :precision binary64 (/ 4.0 (* (* 3.0 PI) (sqrt (- 2.0 (* 6.0 (* v v)))))))
double code(double v) {
return 4.0 / ((3.0 * ((double) M_PI)) * sqrt((2.0 - (6.0 * (v * v)))));
}
public static double code(double v) {
return 4.0 / ((3.0 * Math.PI) * Math.sqrt((2.0 - (6.0 * (v * v)))));
}
def code(v): return 4.0 / ((3.0 * math.pi) * math.sqrt((2.0 - (6.0 * (v * v)))))
function code(v) return Float64(4.0 / Float64(Float64(3.0 * pi) * sqrt(Float64(2.0 - Float64(6.0 * Float64(v * v)))))) end
function tmp = code(v) tmp = 4.0 / ((3.0 * pi) * sqrt((2.0 - (6.0 * (v * v))))); end
code[v_] := N[(4.0 / N[(N[(3.0 * Pi), $MachinePrecision] * N[Sqrt[N[(2.0 - N[(6.0 * N[(v * v), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{4}{\left(3 \cdot \pi\right) \cdot \sqrt{2 - 6 \cdot \left(v \cdot v\right)}}
\end{array}
Initial program 98.5%
Taylor expanded in v around 0
lift-*.f64N/A
lift-PI.f6497.4
Applied rewrites97.4%
(FPCore (v) :precision binary64 (* 1.3333333333333333 (/ (sqrt 0.5) PI)))
double code(double v) {
return 1.3333333333333333 * (sqrt(0.5) / ((double) M_PI));
}
public static double code(double v) {
return 1.3333333333333333 * (Math.sqrt(0.5) / Math.PI);
}
def code(v): return 1.3333333333333333 * (math.sqrt(0.5) / math.pi)
function code(v) return Float64(1.3333333333333333 * Float64(sqrt(0.5) / pi)) end
function tmp = code(v) tmp = 1.3333333333333333 * (sqrt(0.5) / pi); end
code[v_] := N[(1.3333333333333333 * N[(N[Sqrt[0.5], $MachinePrecision] / Pi), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
1.3333333333333333 \cdot \frac{\sqrt{0.5}}{\pi}
\end{array}
Initial program 98.5%
Taylor expanded in v around 0
lower-*.f64N/A
lower-/.f64N/A
lower-sqrt.f64N/A
lift-PI.f6497.3
Applied rewrites97.3%
herbie shell --seed 2025134
(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)))))))