
(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 4 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 (* 0.3333333333333333 (acos (/ (- g) h))))) (- (fma (sin t_0) (sqrt 3.0) (cos (pow (sqrt t_0) 2.0))))))
double code(double g, double h) {
double t_0 = 0.3333333333333333 * acos((-g / h));
return -fma(sin(t_0), sqrt(3.0), cos(pow(sqrt(t_0), 2.0)));
}
function code(g, h) t_0 = Float64(0.3333333333333333 * acos(Float64(Float64(-g) / h))) return Float64(-fma(sin(t_0), sqrt(3.0), cos((sqrt(t_0) ^ 2.0)))) end
code[g_, h_] := Block[{t$95$0 = N[(0.3333333333333333 * N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, (-N[(N[Sin[t$95$0], $MachinePrecision] * N[Sqrt[3.0], $MachinePrecision] + N[Cos[N[Power[N[Sqrt[t$95$0], $MachinePrecision], 2.0], $MachinePrecision]], $MachinePrecision]), $MachinePrecision])]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 0.3333333333333333 \cdot \cos^{-1} \left(\frac{-g}{h}\right)\\
-\mathsf{fma}\left(\sin t\_0, \sqrt{3}, \cos \left({\left(\sqrt{t\_0}\right)}^{2}\right)\right)
\end{array}
\end{array}
Initial program 98.4%
Applied egg-rr100.0%
Applied egg-rr100.0%
Taylor expanded in g around 0
distribute-lft-outN/A
associate-*r*N/A
metadata-evalN/A
mul-1-negN/A
neg-lowering-neg.f64N/A
+-commutativeN/A
accelerator-lowering-fma.f64N/A
Simplified100.0%
*-commutativeN/A
rem-square-sqrtN/A
unpow2N/A
pow-lowering-pow.f64N/A
sqrt-lowering-sqrt.f64N/A
*-commutativeN/A
*-lowering-*.f64N/A
acos-lowering-acos.f64N/A
/-lowering-/.f64N/A
neg-lowering-neg.f64100.0
Applied egg-rr100.0%
Final simplification100.0%
(FPCore (g h) :precision binary64 (let* ((t_0 (* 0.3333333333333333 (acos (/ (- g) h))))) (- (fma (sin t_0) (sqrt 3.0) (cos t_0)))))
double code(double g, double h) {
double t_0 = 0.3333333333333333 * acos((-g / h));
return -fma(sin(t_0), sqrt(3.0), cos(t_0));
}
function code(g, h) t_0 = Float64(0.3333333333333333 * acos(Float64(Float64(-g) / h))) return Float64(-fma(sin(t_0), sqrt(3.0), cos(t_0))) end
code[g_, h_] := Block[{t$95$0 = N[(0.3333333333333333 * N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, (-N[(N[Sin[t$95$0], $MachinePrecision] * N[Sqrt[3.0], $MachinePrecision] + N[Cos[t$95$0], $MachinePrecision]), $MachinePrecision])]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 0.3333333333333333 \cdot \cos^{-1} \left(\frac{-g}{h}\right)\\
-\mathsf{fma}\left(\sin t\_0, \sqrt{3}, \cos t\_0\right)
\end{array}
\end{array}
Initial program 98.4%
Applied egg-rr100.0%
Applied egg-rr100.0%
Taylor expanded in g around 0
distribute-lft-outN/A
associate-*r*N/A
metadata-evalN/A
mul-1-negN/A
neg-lowering-neg.f64N/A
+-commutativeN/A
accelerator-lowering-fma.f64N/A
Simplified100.0%
Final simplification100.0%
(FPCore (g h) :precision binary64 (* 2.0 (cos (/ (fma (acos (/ (- g) h)) -3.0 (* PI -6.0)) -9.0))))
double code(double g, double h) {
return 2.0 * cos((fma(acos((-g / h)), -3.0, (((double) M_PI) * -6.0)) / -9.0));
}
function code(g, h) return Float64(2.0 * cos(Float64(fma(acos(Float64(Float64(-g) / h)), -3.0, Float64(pi * -6.0)) / -9.0))) end
code[g_, h_] := N[(2.0 * N[Cos[N[(N[(N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision] * -3.0 + N[(Pi * -6.0), $MachinePrecision]), $MachinePrecision] / -9.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot \cos \left(\frac{\mathsf{fma}\left(\cos^{-1} \left(\frac{-g}{h}\right), -3, \pi \cdot -6\right)}{-9}\right)
\end{array}
Initial program 98.4%
+-commutativeN/A
frac-2negN/A
frac-addN/A
/-lowering-/.f64N/A
Applied egg-rr98.4%
(FPCore (g h) :precision binary64 (* 2.0 (cos (fma (acos (/ (- g) h)) 0.3333333333333333 (* PI 0.6666666666666666)))))
double code(double g, double h) {
return 2.0 * cos(fma(acos((-g / h)), 0.3333333333333333, (((double) M_PI) * 0.6666666666666666)));
}
function code(g, h) return Float64(2.0 * cos(fma(acos(Float64(Float64(-g) / h)), 0.3333333333333333, Float64(pi * 0.6666666666666666)))) end
code[g_, h_] := N[(2.0 * N[Cos[N[(N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision] * 0.3333333333333333 + N[(Pi * 0.6666666666666666), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot \cos \left(\mathsf{fma}\left(\cos^{-1} \left(\frac{-g}{h}\right), 0.3333333333333333, \pi \cdot 0.6666666666666666\right)\right)
\end{array}
Initial program 98.4%
*-commutativeN/A
*-lowering-*.f64N/A
Applied egg-rr98.4%
Final simplification98.4%
herbie shell --seed 2024199
(FPCore (g h)
:name "2-ancestry mixing, negative discriminant"
:precision binary64
(* 2.0 (cos (+ (/ (* 2.0 PI) 3.0) (/ (acos (/ (- g) h)) 3.0)))))