
(FPCore (g h a) :precision binary64 (let* ((t_0 (/ 1.0 (* 2.0 a))) (t_1 (sqrt (- (* g g) (* h h))))) (+ (cbrt (* t_0 (+ (- g) t_1))) (cbrt (* t_0 (- (- g) t_1))))))
double code(double g, double h, double a) {
double t_0 = 1.0 / (2.0 * a);
double t_1 = sqrt(((g * g) - (h * h)));
return cbrt((t_0 * (-g + t_1))) + cbrt((t_0 * (-g - t_1)));
}
public static double code(double g, double h, double a) {
double t_0 = 1.0 / (2.0 * a);
double t_1 = Math.sqrt(((g * g) - (h * h)));
return Math.cbrt((t_0 * (-g + t_1))) + Math.cbrt((t_0 * (-g - t_1)));
}
function code(g, h, a) t_0 = Float64(1.0 / Float64(2.0 * a)) t_1 = sqrt(Float64(Float64(g * g) - Float64(h * h))) return Float64(cbrt(Float64(t_0 * Float64(Float64(-g) + t_1))) + cbrt(Float64(t_0 * Float64(Float64(-g) - t_1)))) end
code[g_, h_, a_] := Block[{t$95$0 = N[(1.0 / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Sqrt[N[(N[(g * g), $MachinePrecision] - N[(h * h), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, N[(N[Power[N[(t$95$0 * N[((-g) + t$95$1), $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision] + N[Power[N[(t$95$0 * N[((-g) - t$95$1), $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{2 \cdot a}\\
t_1 := \sqrt{g \cdot g - h \cdot h}\\
\sqrt[3]{t\_0 \cdot \left(\left(-g\right) + t\_1\right)} + \sqrt[3]{t\_0 \cdot \left(\left(-g\right) - t\_1\right)}
\end{array}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (g h a) :precision binary64 (let* ((t_0 (/ 1.0 (* 2.0 a))) (t_1 (sqrt (- (* g g) (* h h))))) (+ (cbrt (* t_0 (+ (- g) t_1))) (cbrt (* t_0 (- (- g) t_1))))))
double code(double g, double h, double a) {
double t_0 = 1.0 / (2.0 * a);
double t_1 = sqrt(((g * g) - (h * h)));
return cbrt((t_0 * (-g + t_1))) + cbrt((t_0 * (-g - t_1)));
}
public static double code(double g, double h, double a) {
double t_0 = 1.0 / (2.0 * a);
double t_1 = Math.sqrt(((g * g) - (h * h)));
return Math.cbrt((t_0 * (-g + t_1))) + Math.cbrt((t_0 * (-g - t_1)));
}
function code(g, h, a) t_0 = Float64(1.0 / Float64(2.0 * a)) t_1 = sqrt(Float64(Float64(g * g) - Float64(h * h))) return Float64(cbrt(Float64(t_0 * Float64(Float64(-g) + t_1))) + cbrt(Float64(t_0 * Float64(Float64(-g) - t_1)))) end
code[g_, h_, a_] := Block[{t$95$0 = N[(1.0 / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Sqrt[N[(N[(g * g), $MachinePrecision] - N[(h * h), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]}, N[(N[Power[N[(t$95$0 * N[((-g) + t$95$1), $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision] + N[Power[N[(t$95$0 * N[((-g) - t$95$1), $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \frac{1}{2 \cdot a}\\
t_1 := \sqrt{g \cdot g - h \cdot h}\\
\sqrt[3]{t\_0 \cdot \left(\left(-g\right) + t\_1\right)} + \sqrt[3]{t\_0 \cdot \left(\left(-g\right) - t\_1\right)}
\end{array}
\end{array}
(FPCore (g h a) :precision binary64 (fma (/ (* (cbrt g) (cbrt -0.5)) (cbrt a)) (pow 2.0 0.3333333333333333) (* (/ (cbrt (* (/ h g) h)) (cbrt a)) (* (cbrt 0.5) (cbrt -0.5)))))
double code(double g, double h, double a) {
return fma(((cbrt(g) * cbrt(-0.5)) / cbrt(a)), pow(2.0, 0.3333333333333333), ((cbrt(((h / g) * h)) / cbrt(a)) * (cbrt(0.5) * cbrt(-0.5))));
}
function code(g, h, a) return fma(Float64(Float64(cbrt(g) * cbrt(-0.5)) / cbrt(a)), (2.0 ^ 0.3333333333333333), Float64(Float64(cbrt(Float64(Float64(h / g) * h)) / cbrt(a)) * Float64(cbrt(0.5) * cbrt(-0.5)))) end
code[g_, h_, a_] := N[(N[(N[(N[Power[g, 1/3], $MachinePrecision] * N[Power[-0.5, 1/3], $MachinePrecision]), $MachinePrecision] / N[Power[a, 1/3], $MachinePrecision]), $MachinePrecision] * N[Power[2.0, 0.3333333333333333], $MachinePrecision] + N[(N[(N[Power[N[(N[(h / g), $MachinePrecision] * h), $MachinePrecision], 1/3], $MachinePrecision] / N[Power[a, 1/3], $MachinePrecision]), $MachinePrecision] * N[(N[Power[0.5, 1/3], $MachinePrecision] * N[Power[-0.5, 1/3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\mathsf{fma}\left(\frac{\sqrt[3]{g} \cdot \sqrt[3]{-0.5}}{\sqrt[3]{a}}, {2}^{0.3333333333333333}, \frac{\sqrt[3]{\frac{h}{g} \cdot h}}{\sqrt[3]{a}} \cdot \left(\sqrt[3]{0.5} \cdot \sqrt[3]{-0.5}\right)\right)
\end{array}
Initial program 42.8%
Taylor expanded in h around 0
associate-*r*N/A
lower-fma.f64N/A
lower-*.f64N/A
lower-cbrt.f64N/A
lower-/.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f64N/A
lower-*.f64N/A
lower-cbrt.f64N/A
unpow2N/A
*-commutativeN/A
times-fracN/A
lower-*.f64N/A
lower-/.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f6473.6
Applied rewrites73.6%
Applied rewrites92.4%
Applied rewrites93.1%
Applied rewrites97.8%
(FPCore (g h a) :precision binary64 (/ (* (cbrt g) (cbrt -1.0)) (cbrt a)))
double code(double g, double h, double a) {
return (cbrt(g) * cbrt(-1.0)) / cbrt(a);
}
public static double code(double g, double h, double a) {
return (Math.cbrt(g) * Math.cbrt(-1.0)) / Math.cbrt(a);
}
function code(g, h, a) return Float64(Float64(cbrt(g) * cbrt(-1.0)) / cbrt(a)) end
code[g_, h_, a_] := N[(N[(N[Power[g, 1/3], $MachinePrecision] * N[Power[-1.0, 1/3], $MachinePrecision]), $MachinePrecision] / N[Power[a, 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sqrt[3]{g} \cdot \sqrt[3]{-1}}{\sqrt[3]{a}}
\end{array}
Initial program 42.8%
lift-cbrt.f64N/A
lift-*.f64N/A
lift-/.f64N/A
associate-*l/N/A
cbrt-divN/A
*-lft-identityN/A
lower-/.f64N/A
Applied rewrites45.5%
Taylor expanded in g around inf
lower-*.f64N/A
lower-cbrt.f64N/A
lower-/.f64N/A
lower-cbrt.f6473.4
Applied rewrites73.4%
Applied rewrites96.6%
(FPCore (g h a) :precision binary64 (+ (cbrt (* -0.25 (* (/ h a) (/ h g)))) (cbrt (/ (- g) a))))
double code(double g, double h, double a) {
return cbrt((-0.25 * ((h / a) * (h / g)))) + cbrt((-g / a));
}
public static double code(double g, double h, double a) {
return Math.cbrt((-0.25 * ((h / a) * (h / g)))) + Math.cbrt((-g / a));
}
function code(g, h, a) return Float64(cbrt(Float64(-0.25 * Float64(Float64(h / a) * Float64(h / g)))) + cbrt(Float64(Float64(-g) / a))) end
code[g_, h_, a_] := N[(N[Power[N[(-0.25 * N[(N[(h / a), $MachinePrecision] * N[(h / g), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision] + N[Power[N[((-g) / a), $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt[3]{-0.25 \cdot \left(\frac{h}{a} \cdot \frac{h}{g}\right)} + \sqrt[3]{\frac{-g}{a}}
\end{array}
Initial program 42.8%
Taylor expanded in h around 0
associate-*r*N/A
lower-fma.f64N/A
lower-*.f64N/A
lower-cbrt.f64N/A
lower-/.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f64N/A
lower-*.f64N/A
lower-cbrt.f64N/A
unpow2N/A
*-commutativeN/A
times-fracN/A
lower-*.f64N/A
lower-/.f64N/A
lower-/.f64N/A
*-commutativeN/A
lower-*.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f6473.6
Applied rewrites73.6%
Applied rewrites92.4%
Applied rewrites93.1%
Applied rewrites74.4%
Final simplification74.4%
(FPCore (g h a) :precision binary64 (cbrt (/ (- g) a)))
double code(double g, double h, double a) {
return cbrt((-g / a));
}
public static double code(double g, double h, double a) {
return Math.cbrt((-g / a));
}
function code(g, h, a) return cbrt(Float64(Float64(-g) / a)) end
code[g_, h_, a_] := N[Power[N[((-g) / a), $MachinePrecision], 1/3], $MachinePrecision]
\begin{array}{l}
\\
\sqrt[3]{\frac{-g}{a}}
\end{array}
Initial program 42.8%
lift-cbrt.f64N/A
lift-*.f64N/A
lift-/.f64N/A
associate-*l/N/A
cbrt-divN/A
*-lft-identityN/A
lower-/.f64N/A
Applied rewrites45.5%
Taylor expanded in g around inf
lower-*.f64N/A
lower-cbrt.f64N/A
lower-/.f64N/A
lower-cbrt.f6473.4
Applied rewrites73.4%
Applied rewrites73.4%
Final simplification73.4%
herbie shell --seed 2024351
(FPCore (g h a)
:name "2-ancestry mixing, positive discriminant"
:precision binary64
(+ (cbrt (* (/ 1.0 (* 2.0 a)) (+ (- g) (sqrt (- (* g g) (* h h)))))) (cbrt (* (/ 1.0 (* 2.0 a)) (- (- g) (sqrt (- (* g g) (* h h))))))))