
(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}
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}
Herbie found 3 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}
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}
(FPCore (g h a) :precision binary64 (let* ((t_0 (* g (+ 1.0 (* 0.5 (/ (+ h (* -1.0 h)) g)))))) (fma (cbrt (/ 1.0 a)) (cbrt (/ (+ t_0 g) -2.0)) (cbrt (/ (- t_0 g) (+ a a))))))
double code(double g, double h, double a) {
double t_0 = g * (1.0 + (0.5 * ((h + (-1.0 * h)) / g)));
return fma(cbrt((1.0 / a)), cbrt(((t_0 + g) / -2.0)), cbrt(((t_0 - g) / (a + a))));
}
function code(g, h, a) t_0 = Float64(g * Float64(1.0 + Float64(0.5 * Float64(Float64(h + Float64(-1.0 * h)) / g)))) return fma(cbrt(Float64(1.0 / a)), cbrt(Float64(Float64(t_0 + g) / -2.0)), cbrt(Float64(Float64(t_0 - g) / Float64(a + a)))) end
code[g_, h_, a_] := Block[{t$95$0 = N[(g * N[(1.0 + N[(0.5 * N[(N[(h + N[(-1.0 * h), $MachinePrecision]), $MachinePrecision] / g), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(N[Power[N[(1.0 / a), $MachinePrecision], 1/3], $MachinePrecision] * N[Power[N[(N[(t$95$0 + g), $MachinePrecision] / -2.0), $MachinePrecision], 1/3], $MachinePrecision] + N[Power[N[(N[(t$95$0 - g), $MachinePrecision] / N[(a + a), $MachinePrecision]), $MachinePrecision], 1/3], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
t_0 := g \cdot \left(1 + 0.5 \cdot \frac{h + -1 \cdot h}{g}\right)\\
\mathsf{fma}\left(\sqrt[3]{\frac{1}{a}}, \sqrt[3]{\frac{t\_0 + g}{-2}}, \sqrt[3]{\frac{t\_0 - g}{a + a}}\right)
\end{array}
Initial program 44.7%
Applied rewrites47.5%
Taylor expanded in g around inf
lower-*.f64N/A
lower-+.f64N/A
lower-*.f64N/A
lower-/.f64N/A
lower-+.f64N/A
lower-*.f6432.8%
Applied rewrites32.8%
Taylor expanded in g around inf
lower-*.f64N/A
lower-+.f64N/A
lower-*.f64N/A
lower-/.f64N/A
lower-+.f64N/A
lower-*.f6495.6%
Applied rewrites95.6%
(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(Float64(-cbrt(g)) / cbrt(a)) end
code[g_, h_, a_] := N[((-N[Power[g, 1/3], $MachinePrecision]) / N[Power[a, 1/3], $MachinePrecision]), $MachinePrecision]
\frac{-\sqrt[3]{g}}{\sqrt[3]{a}}
Initial program 44.7%
lift-+.f64N/A
+-commutativeN/A
lift-cbrt.f64N/A
lift-*.f64N/A
cbrt-prodN/A
lift-cbrt.f64N/A
lift-*.f64N/A
cbrt-prodN/A
Applied rewrites23.9%
Taylor expanded in g around inf
lower-*.f64N/A
lower-/.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f6495.8%
Applied rewrites95.8%
lift-*.f64N/A
mul-1-negN/A
lift-/.f64N/A
distribute-neg-fracN/A
lower-/.f64N/A
lower-neg.f6495.8%
Applied rewrites95.8%
(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 Float64(-cbrt(Float64(g / a))) end
code[g_, h_, a_] := (-N[Power[N[(g / a), $MachinePrecision], 1/3], $MachinePrecision])
-\sqrt[3]{\frac{g}{a}}
Initial program 44.7%
lift-+.f64N/A
+-commutativeN/A
lift-cbrt.f64N/A
lift-*.f64N/A
cbrt-prodN/A
lift-cbrt.f64N/A
lift-*.f64N/A
cbrt-prodN/A
Applied rewrites23.9%
Taylor expanded in g around inf
lower-*.f64N/A
lower-/.f64N/A
lower-cbrt.f64N/A
lower-cbrt.f6495.8%
Applied rewrites95.8%
lift-*.f64N/A
mul-1-negN/A
lower-neg.f6495.8%
lift-/.f64N/A
lift-cbrt.f64N/A
lift-cbrt.f64N/A
cbrt-undivN/A
lift-/.f64N/A
lower-cbrt.f6473.7%
Applied rewrites73.7%
herbie shell --seed 2025213
(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))))))))