
(FPCore (g h) :precision binary64 (* 2.0 (cos (+ (/ (* 2.0 (PI)) 3.0) (/ (acos (/ (- g) h)) 3.0)))))
2 \cdot \cos \left(\frac{2 \cdot \mathsf{PI}\left(\right)}{3} + \frac{\cos^{-1} \left(\frac{-g}{h}\right)}{3}\right)
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (g h) :precision binary64 (* 2.0 (cos (+ (/ (* 2.0 (PI)) 3.0) (/ (acos (/ (- g) h)) 3.0)))))
2 \cdot \cos \left(\frac{2 \cdot \mathsf{PI}\left(\right)}{3} + \frac{\cos^{-1} \left(\frac{-g}{h}\right)}{3}\right)
(FPCore (g h)
:precision binary64
(*
2.0
(sin
(fma
(cbrt (* (PI) (PI)))
(* (cbrt (PI)) 0.5)
(fma
-0.3333333333333333
(acos (/ (- g) h))
(* -0.6666666666666666 (PI)))))))2 \cdot \sin \left(\mathsf{fma}\left(\sqrt[3]{\mathsf{PI}\left(\right) \cdot \mathsf{PI}\left(\right)}, \sqrt[3]{\mathsf{PI}\left(\right)} \cdot 0.5, \mathsf{fma}\left(-0.3333333333333333, \cos^{-1} \left(\frac{-g}{h}\right), -0.6666666666666666 \cdot \mathsf{PI}\left(\right)\right)\right)\right)
Initial program 98.5%
lift-cos.f64N/A
cos-neg-revN/A
sin-+PI/2-revN/A
lower-sin.f64N/A
lower-+.f64N/A
Applied rewrites98.5%
lift-+.f64N/A
+-commutativeN/A
lift-*.f64N/A
lift-PI.f64N/A
add-cube-cbrtN/A
associate-*l*N/A
lower-fma.f64N/A
Applied rewrites100.0%
(FPCore (g h)
:precision binary64
(*
(sin
(fma
-0.6666666666666666
(PI)
(fma -0.3333333333333333 (acos (/ (- g) h)) 1.5707963267948966)))
2.0))\sin \left(\mathsf{fma}\left(-0.6666666666666666, \mathsf{PI}\left(\right), \mathsf{fma}\left(-0.3333333333333333, \cos^{-1} \left(\frac{-g}{h}\right), 1.5707963267948966\right)\right)\right) \cdot 2
Initial program 98.5%
lift-cos.f64N/A
cos-neg-revN/A
sin-+PI/2-revN/A
lower-sin.f64N/A
lower-+.f64N/A
Applied rewrites98.5%
Evaluated real constant98.5%
lift-+.f64N/A
lift-/.f64N/A
lift-fma.f64N/A
div-addN/A
associate-/l*N/A
metadata-evalN/A
*-commutativeN/A
mult-flip-revN/A
metadata-evalN/A
*-commutativeN/A
lift-*.f64N/A
associate-+l+N/A
lift-*.f64N/A
*-commutativeN/A
lower-fma.f64N/A
*-commutativeN/A
lower-fma.f6499.9
Applied rewrites99.9%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6499.9
lift-fma.f64N/A
*-commutativeN/A
lower-fma.f6499.9
lift-fma.f64N/A
*-commutativeN/A
lower-fma.f6499.9
Applied rewrites99.9%
(FPCore (g h) :precision binary64 (* (cos (fma -0.3333333333333333 (- (PI) (acos (/ g h))) -2.0943951023931957)) 2.0))
\cos \left(\mathsf{fma}\left(-0.3333333333333333, \mathsf{PI}\left(\right) - \cos^{-1} \left(\frac{g}{h}\right), -2.0943951023931957\right)\right) \cdot 2
Initial program 98.5%
Evaluated real constant98.4%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.4
Applied rewrites98.4%
lift-acos.f64N/A
lift-/.f64N/A
lift-neg.f64N/A
distribute-frac-negN/A
acos-negN/A
lift-PI.f64N/A
lower--.f64N/A
lower-acos.f64N/A
lower-/.f6498.5
Applied rewrites98.5%
(FPCore (g h) :precision binary64 (* (cos (fma -0.3333333333333333 (acos (/ (- g) h)) -2.0943951023931957)) 2.0))
double code(double g, double h) {
return cos(fma(-0.3333333333333333, acos((-g / h)), -2.0943951023931957)) * 2.0;
}
function code(g, h) return Float64(cos(fma(-0.3333333333333333, acos(Float64(Float64(-g) / h)), -2.0943951023931957)) * 2.0) end
code[g_, h_] := N[(N[Cos[N[(-0.3333333333333333 * N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision] + -2.0943951023931957), $MachinePrecision]], $MachinePrecision] * 2.0), $MachinePrecision]
\cos \left(\mathsf{fma}\left(-0.3333333333333333, \cos^{-1} \left(\frac{-g}{h}\right), -2.0943951023931957\right)\right) \cdot 2
Initial program 98.5%
Evaluated real constant98.4%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6498.4
Applied rewrites98.4%
(FPCore (g h) :precision binary64 (* (sin (fma 0.3333333333333333 (acos (/ (- g) h)) 3.6651914291880923)) 2.0))
double code(double g, double h) {
return sin(fma(0.3333333333333333, acos((-g / h)), 3.6651914291880923)) * 2.0;
}
function code(g, h) return Float64(sin(fma(0.3333333333333333, acos(Float64(Float64(-g) / h)), 3.6651914291880923)) * 2.0) end
code[g_, h_] := N[(N[Sin[N[(0.3333333333333333 * N[ArcCos[N[((-g) / h), $MachinePrecision]], $MachinePrecision] + 3.6651914291880923), $MachinePrecision]], $MachinePrecision] * 2.0), $MachinePrecision]
\sin \left(\mathsf{fma}\left(0.3333333333333333, \cos^{-1} \left(\frac{-g}{h}\right), 3.6651914291880923\right)\right) \cdot 2
Initial program 98.5%
lift-cos.f64N/A
sin-+PI/2-revN/A
lower-sin.f64N/A
lift-+.f64N/A
+-commutativeN/A
associate-+l+N/A
lift-/.f64N/A
mult-flipN/A
*-commutativeN/A
lower-fma.f64N/A
metadata-evalN/A
lift-/.f64N/A
lift-*.f64N/A
*-commutativeN/A
associate-/l*N/A
Applied rewrites97.5%
Evaluated real constant97.6%
lift-*.f64N/A
*-commutativeN/A
lower-*.f6497.6
Applied rewrites97.6%
herbie shell --seed 2025175
(FPCore (g h)
:name "2-ancestry mixing, negative discriminant"
:precision binary64
(* 2.0 (cos (+ (/ (* 2.0 (PI)) 3.0) (/ (acos (/ (- g) h)) 3.0)))))