
(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 6 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 (- g)) (cbrt a)))
double code(double g, double h, double a) {
return cbrt(-g) / cbrt(a);
}
public static double code(double g, double h, double a) {
return Math.cbrt(-g) / Math.cbrt(a);
}
function code(g, h, a) return Float64(cbrt(Float64(-g)) / cbrt(a)) end
code[g_, h_, a_] := N[(N[Power[(-g), 1/3], $MachinePrecision] / N[Power[a, 1/3], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\sqrt[3]{-g}}{\sqrt[3]{a}}
\end{array}
Initial program 46.0%
Applied rewrites49.2%
Taylor expanded in g around inf
lower-*.f64N/A
lower-cbrt.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f6472.3
Applied rewrites72.3%
Applied rewrites95.4%
(FPCore (g h a) :precision binary64 (if (<= (/ 1.0 (* a 2.0)) 1e-297) (/ 1.0 (cbrt (/ a (- g)))) (* (cbrt (- g)) (pow a -0.3333333333333333))))
double code(double g, double h, double a) {
double tmp;
if ((1.0 / (a * 2.0)) <= 1e-297) {
tmp = 1.0 / cbrt((a / -g));
} else {
tmp = cbrt(-g) * pow(a, -0.3333333333333333);
}
return tmp;
}
public static double code(double g, double h, double a) {
double tmp;
if ((1.0 / (a * 2.0)) <= 1e-297) {
tmp = 1.0 / Math.cbrt((a / -g));
} else {
tmp = Math.cbrt(-g) * Math.pow(a, -0.3333333333333333);
}
return tmp;
}
function code(g, h, a) tmp = 0.0 if (Float64(1.0 / Float64(a * 2.0)) <= 1e-297) tmp = Float64(1.0 / cbrt(Float64(a / Float64(-g)))); else tmp = Float64(cbrt(Float64(-g)) * (a ^ -0.3333333333333333)); end return tmp end
code[g_, h_, a_] := If[LessEqual[N[(1.0 / N[(a * 2.0), $MachinePrecision]), $MachinePrecision], 1e-297], N[(1.0 / N[Power[N[(a / (-g)), $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision], N[(N[Power[(-g), 1/3], $MachinePrecision] * N[Power[a, -0.3333333333333333], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\frac{1}{a \cdot 2} \leq 10^{-297}:\\
\;\;\;\;\frac{1}{\sqrt[3]{\frac{a}{-g}}}\\
\mathbf{else}:\\
\;\;\;\;\sqrt[3]{-g} \cdot {a}^{-0.3333333333333333}\\
\end{array}
\end{array}
if (/.f64 #s(literal 1 binary64) (*.f64 #s(literal 2 binary64) a)) < 1.00000000000000004e-297Initial program 43.9%
Applied rewrites47.4%
Taylor expanded in g around inf
lower-*.f64N/A
lower-cbrt.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f6473.7
Applied rewrites73.7%
Applied rewrites74.8%
if 1.00000000000000004e-297 < (/.f64 #s(literal 1 binary64) (*.f64 #s(literal 2 binary64) a)) Initial program 44.5%
Applied rewrites47.2%
Taylor expanded in g around inf
lower-*.f64N/A
lower-cbrt.f64N/A
lower-/.f64N/A
lower-*.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f6473.7
Applied rewrites73.7%
Applied rewrites89.8%
Final simplification82.1%
herbie shell --seed 2024225
(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))))))))