
(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}
Herbie found 2 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 (* (cbrt -1.0) (/ (cbrt g) (cbrt a))))
double code(double g, double h, double a) {
return cbrt(-1.0) * (cbrt(g) / cbrt(a));
}
public static double code(double g, double h, double a) {
return Math.cbrt(-1.0) * (Math.cbrt(g) / Math.cbrt(a));
}
function code(g, h, a) return Float64(cbrt(-1.0) * Float64(cbrt(g) / cbrt(a))) end
code[g_, h_, a_] := N[(N[Power[-1.0, 1/3], $MachinePrecision] * N[(N[Power[g, 1/3], $MachinePrecision] / N[Power[a, 1/3], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\sqrt[3]{-1} \cdot \frac{\sqrt[3]{g}}{\sqrt[3]{a}}
\end{array}
Initial program 44.2%
Taylor expanded in g around inf
cbrt-unprodN/A
metadata-evalN/A
*-commutativeN/A
lower-*.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f64N/A
lower-/.f6473.1
Applied rewrites73.1%
lift-/.f64N/A
lift-cbrt.f64N/A
cbrt-divN/A
lower-/.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f6495.7
Applied rewrites95.7%
(FPCore (g h a) :precision binary64 (cbrt (* (/ g a) -1.0)))
double code(double g, double h, double a) {
return cbrt(((g / a) * -1.0));
}
public static double code(double g, double h, double a) {
return Math.cbrt(((g / a) * -1.0));
}
function code(g, h, a) return cbrt(Float64(Float64(g / a) * -1.0)) end
code[g_, h_, a_] := N[Power[N[(N[(g / a), $MachinePrecision] * -1.0), $MachinePrecision], 1/3], $MachinePrecision]
\begin{array}{l}
\\
\sqrt[3]{\frac{g}{a} \cdot -1}
\end{array}
Initial program 44.2%
lift-cbrt.f64N/A
lift-*.f64N/A
lift-neg.f64N/A
lift-+.f64N/A
lift-sqrt.f64N/A
lift--.f64N/A
lift-*.f64N/A
lift-*.f64N/A
cbrt-prodN/A
lower-*.f64N/A
Applied rewrites47.3%
Taylor expanded in g around inf
cbrt-unprodN/A
metadata-evalN/A
cbrt-unprodN/A
lower-cbrt.f64N/A
lower-*.f64N/A
lift-/.f6473.1
Applied rewrites73.1%
herbie shell --seed 2025101
(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))))))))