
(FPCore (g h) :precision binary64 (* 2.0 (cos (+ (/ (* 2.0 PI) 3.0) (/ (acos (/ (- g) h)) 3.0)))))
double code(double g, double h) {
return 2.0 * cos((((2.0 * ((double) M_PI)) / 3.0) + (acos((-g / h)) / 3.0)));
}
public static double code(double g, double h) {
return 2.0 * Math.cos((((2.0 * Math.PI) / 3.0) + (Math.acos((-g / h)) / 3.0)));
}
def code(g, h): return 2.0 * math.cos((((2.0 * math.pi) / 3.0) + (math.acos((-g / h)) / 3.0)))
function code(g, h) return Float64(2.0 * cos(Float64(Float64(Float64(2.0 * pi) / 3.0) + Float64(acos(Float64(Float64(-g) / h)) / 3.0)))) end
function tmp = code(g, h) tmp = 2.0 * cos((((2.0 * pi) / 3.0) + (acos((-g / h)) / 3.0))); end
code[g_, h_] := N[(2.0 * N[Cos[N[(N[(N[(2.0 * Pi), $MachinePrecision] / 3.0), $MachinePrecision] + N[(N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision] / 3.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot \cos \left(\frac{2 \cdot \pi}{3} + \frac{\cos^{-1} \left(\frac{-g}{h}\right)}{3}\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 3 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (g h) :precision binary64 (* 2.0 (cos (+ (/ (* 2.0 PI) 3.0) (/ (acos (/ (- g) h)) 3.0)))))
double code(double g, double h) {
return 2.0 * cos((((2.0 * ((double) M_PI)) / 3.0) + (acos((-g / h)) / 3.0)));
}
public static double code(double g, double h) {
return 2.0 * Math.cos((((2.0 * Math.PI) / 3.0) + (Math.acos((-g / h)) / 3.0)));
}
def code(g, h): return 2.0 * math.cos((((2.0 * math.pi) / 3.0) + (math.acos((-g / h)) / 3.0)))
function code(g, h) return Float64(2.0 * cos(Float64(Float64(Float64(2.0 * pi) / 3.0) + Float64(acos(Float64(Float64(-g) / h)) / 3.0)))) end
function tmp = code(g, h) tmp = 2.0 * cos((((2.0 * pi) / 3.0) + (acos((-g / h)) / 3.0))); end
code[g_, h_] := N[(2.0 * N[Cos[N[(N[(N[(2.0 * Pi), $MachinePrecision] / 3.0), $MachinePrecision] + N[(N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision] / 3.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot \cos \left(\frac{2 \cdot \pi}{3} + \frac{\cos^{-1} \left(\frac{-g}{h}\right)}{3}\right)
\end{array}
(FPCore (g h)
:precision binary64
(let* ((t_0 (acos (/ (- g) h)))
(t_1
(/
(* -0.1111111111111111 (pow t_0 2.0))
(fma PI -0.6666666666666666 (* 0.3333333333333333 t_0)))))
(*
(fma
(cos
(/
(* (* PI PI) 0.4444444444444444)
(fma -0.3333333333333333 t_0 (* 0.6666666666666666 PI))))
(cos t_1)
(*
(sin t_1)
(sin (/ (* -1.3333333333333333 (* PI PI)) (fma -2.0 PI t_0)))))
2.0)))
double code(double g, double h) {
double t_0 = acos((-g / h));
double t_1 = (-0.1111111111111111 * pow(t_0, 2.0)) / fma(((double) M_PI), -0.6666666666666666, (0.3333333333333333 * t_0));
return fma(cos((((((double) M_PI) * ((double) M_PI)) * 0.4444444444444444) / fma(-0.3333333333333333, t_0, (0.6666666666666666 * ((double) M_PI))))), cos(t_1), (sin(t_1) * sin(((-1.3333333333333333 * (((double) M_PI) * ((double) M_PI))) / fma(-2.0, ((double) M_PI), t_0))))) * 2.0;
}
function code(g, h) t_0 = acos(Float64(Float64(-g) / h)) t_1 = Float64(Float64(-0.1111111111111111 * (t_0 ^ 2.0)) / fma(pi, -0.6666666666666666, Float64(0.3333333333333333 * t_0))) return Float64(fma(cos(Float64(Float64(Float64(pi * pi) * 0.4444444444444444) / fma(-0.3333333333333333, t_0, Float64(0.6666666666666666 * pi)))), cos(t_1), Float64(sin(t_1) * sin(Float64(Float64(-1.3333333333333333 * Float64(pi * pi)) / fma(-2.0, pi, t_0))))) * 2.0) end
code[g_, h_] := Block[{t$95$0 = N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision]}, Block[{t$95$1 = N[(N[(-0.1111111111111111 * N[Power[t$95$0, 2.0], $MachinePrecision]), $MachinePrecision] / N[(Pi * -0.6666666666666666 + N[(0.3333333333333333 * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, N[(N[(N[Cos[N[(N[(N[(Pi * Pi), $MachinePrecision] * 0.4444444444444444), $MachinePrecision] / N[(-0.3333333333333333 * t$95$0 + N[(0.6666666666666666 * Pi), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[Cos[t$95$1], $MachinePrecision] + N[(N[Sin[t$95$1], $MachinePrecision] * N[Sin[N[(N[(-1.3333333333333333 * N[(Pi * Pi), $MachinePrecision]), $MachinePrecision] / N[(-2.0 * Pi + t$95$0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * 2.0), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := \cos^{-1} \left(\frac{-g}{h}\right)\\
t_1 := \frac{-0.1111111111111111 \cdot {t\_0}^{2}}{\mathsf{fma}\left(\pi, -0.6666666666666666, 0.3333333333333333 \cdot t\_0\right)}\\
\mathsf{fma}\left(\cos \left(\frac{\left(\pi \cdot \pi\right) \cdot 0.4444444444444444}{\mathsf{fma}\left(-0.3333333333333333, t\_0, 0.6666666666666666 \cdot \pi\right)}\right), \cos t\_1, \sin t\_1 \cdot \sin \left(\frac{-1.3333333333333333 \cdot \left(\pi \cdot \pi\right)}{\mathsf{fma}\left(-2, \pi, t\_0\right)}\right)\right) \cdot 2
\end{array}
\end{array}
Initial program 98.4%
Applied rewrites98.4%
lift-/.f64N/A
lift-*.f64N/A
associate-/r*N/A
lower-/.f64N/A
lift-*.f64N/A
associate-/l*N/A
lower-*.f64N/A
metadata-eval98.4
Applied rewrites98.4%
lift-/.f64N/A
frac-2negN/A
lift-*.f64N/A
lift-fma.f64N/A
distribute-lft-inN/A
distribute-neg-inN/A
associate-*r*N/A
metadata-evalN/A
lift-*.f64N/A
distribute-neg-inN/A
+-commutativeN/A
lift-fma.f64N/A
Applied rewrites99.9%
Final simplification99.9%
(FPCore (g h)
:precision binary64
(*
(cos
(fma
(* -0.1111111111111111 PI)
-6.0
(* 0.3333333333333333 (acos (/ (- g) h)))))
2.0))
double code(double g, double h) {
return cos(fma((-0.1111111111111111 * ((double) M_PI)), -6.0, (0.3333333333333333 * acos((-g / h))))) * 2.0;
}
function code(g, h) return Float64(cos(fma(Float64(-0.1111111111111111 * pi), -6.0, Float64(0.3333333333333333 * acos(Float64(Float64(-g) / h))))) * 2.0) end
code[g_, h_] := N[(N[Cos[N[(N[(-0.1111111111111111 * Pi), $MachinePrecision] * -6.0 + N[(0.3333333333333333 * N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * 2.0), $MachinePrecision]
\begin{array}{l}
\\
\cos \left(\mathsf{fma}\left(-0.1111111111111111 \cdot \pi, -6, 0.3333333333333333 \cdot \cos^{-1} \left(\frac{-g}{h}\right)\right)\right) \cdot 2
\end{array}
Initial program 98.4%
lift-+.f64N/A
+-commutativeN/A
lift-/.f64N/A
lift-/.f64N/A
frac-2negN/A
frac-addN/A
clear-numN/A
lower-/.f64N/A
lower-/.f64N/A
metadata-evalN/A
metadata-evalN/A
distribute-rgt-neg-outN/A
*-commutativeN/A
distribute-lft-neg-outN/A
lower-fma.f64N/A
Applied rewrites98.5%
lift-/.f64N/A
lift-/.f64N/A
associate-/r/N/A
metadata-evalN/A
lift-fma.f64N/A
+-commutativeN/A
distribute-rgt-inN/A
lower-fma.f64N/A
lower-*.f64N/A
*-commutativeN/A
lower-*.f6498.5
Applied rewrites98.5%
lift-fma.f64N/A
lift-*.f64N/A
associate-*l*N/A
*-commutativeN/A
lower-fma.f64N/A
*-commutativeN/A
lower-*.f6498.5
lift-*.f64N/A
*-commutativeN/A
lift-*.f64N/A
associate-*r*N/A
metadata-evalN/A
lift-*.f6498.5
Applied rewrites98.5%
Final simplification98.5%
herbie shell --seed 2024234
(FPCore (g h)
:name "2-ancestry mixing, negative discriminant"
:precision binary64
(* 2.0 (cos (+ (/ (* 2.0 PI) 3.0) (/ (acos (/ (- g) h)) 3.0)))))