
(FPCore (x) :precision binary64 (- (/ PI 2.0) (* 2.0 (asin (sqrt (/ (- 1.0 x) 2.0))))))
double code(double x) {
return (((double) M_PI) / 2.0) - (2.0 * asin(sqrt(((1.0 - x) / 2.0))));
}
public static double code(double x) {
return (Math.PI / 2.0) - (2.0 * Math.asin(Math.sqrt(((1.0 - x) / 2.0))));
}
def code(x): return (math.pi / 2.0) - (2.0 * math.asin(math.sqrt(((1.0 - x) / 2.0))))
function code(x) return Float64(Float64(pi / 2.0) - Float64(2.0 * asin(sqrt(Float64(Float64(1.0 - x) / 2.0))))) end
function tmp = code(x) tmp = (pi / 2.0) - (2.0 * asin(sqrt(((1.0 - x) / 2.0)))); end
code[x_] := N[(N[(Pi / 2.0), $MachinePrecision] - N[(2.0 * N[ArcSin[N[Sqrt[N[(N[(1.0 - x), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\pi}{2} - 2 \cdot \sin^{-1} \left(\sqrt{\frac{1 - x}{2}}\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (- (/ PI 2.0) (* 2.0 (asin (sqrt (/ (- 1.0 x) 2.0))))))
double code(double x) {
return (((double) M_PI) / 2.0) - (2.0 * asin(sqrt(((1.0 - x) / 2.0))));
}
public static double code(double x) {
return (Math.PI / 2.0) - (2.0 * Math.asin(Math.sqrt(((1.0 - x) / 2.0))));
}
def code(x): return (math.pi / 2.0) - (2.0 * math.asin(math.sqrt(((1.0 - x) / 2.0))))
function code(x) return Float64(Float64(pi / 2.0) - Float64(2.0 * asin(sqrt(Float64(Float64(1.0 - x) / 2.0))))) end
function tmp = code(x) tmp = (pi / 2.0) - (2.0 * asin(sqrt(((1.0 - x) / 2.0)))); end
code[x_] := N[(N[(Pi / 2.0), $MachinePrecision] - N[(2.0 * N[ArcSin[N[Sqrt[N[(N[(1.0 - x), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\pi}{2} - 2 \cdot \sin^{-1} \left(\sqrt{\frac{1 - x}{2}}\right)
\end{array}
(FPCore (x) :precision binary64 (cbrt (pow (fma (- (* PI 0.5) (acos (sqrt (+ 0.5 (* x -0.5))))) -2.0 (* PI 0.5)) 3.0)))
double code(double x) {
return cbrt(pow(fma(((((double) M_PI) * 0.5) - acos(sqrt((0.5 + (x * -0.5))))), -2.0, (((double) M_PI) * 0.5)), 3.0));
}
function code(x) return cbrt((fma(Float64(Float64(pi * 0.5) - acos(sqrt(Float64(0.5 + Float64(x * -0.5))))), -2.0, Float64(pi * 0.5)) ^ 3.0)) end
code[x_] := N[Power[N[Power[N[(N[(N[(Pi * 0.5), $MachinePrecision] - N[ArcCos[N[Sqrt[N[(0.5 + N[(x * -0.5), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * -2.0 + N[(Pi * 0.5), $MachinePrecision]), $MachinePrecision], 3.0], $MachinePrecision], 1/3], $MachinePrecision]
\begin{array}{l}
\\
\sqrt[3]{{\left(\mathsf{fma}\left(\pi \cdot 0.5 - \cos^{-1} \left(\sqrt{0.5 + x \cdot -0.5}\right), -2, \pi \cdot 0.5\right)\right)}^{3}}
\end{array}
Initial program 7.2%
add-cbrt-cube7.2%
pow37.2%
Applied egg-rr7.2%
asin-acos8.8%
div-inv8.8%
metadata-eval8.8%
sub-neg8.8%
distribute-rgt-neg-in8.8%
metadata-eval8.8%
Applied egg-rr8.8%
Final simplification8.8%
(FPCore (x) :precision binary64 (+ (/ PI 2.0) (* 2.0 (- (acos (sqrt (- 0.5 (* 0.5 x)))) (* PI 0.5)))))
double code(double x) {
return (((double) M_PI) / 2.0) + (2.0 * (acos(sqrt((0.5 - (0.5 * x)))) - (((double) M_PI) * 0.5)));
}
public static double code(double x) {
return (Math.PI / 2.0) + (2.0 * (Math.acos(Math.sqrt((0.5 - (0.5 * x)))) - (Math.PI * 0.5)));
}
def code(x): return (math.pi / 2.0) + (2.0 * (math.acos(math.sqrt((0.5 - (0.5 * x)))) - (math.pi * 0.5)))
function code(x) return Float64(Float64(pi / 2.0) + Float64(2.0 * Float64(acos(sqrt(Float64(0.5 - Float64(0.5 * x)))) - Float64(pi * 0.5)))) end
function tmp = code(x) tmp = (pi / 2.0) + (2.0 * (acos(sqrt((0.5 - (0.5 * x)))) - (pi * 0.5))); end
code[x_] := N[(N[(Pi / 2.0), $MachinePrecision] + N[(2.0 * N[(N[ArcCos[N[Sqrt[N[(0.5 - N[(0.5 * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision] - N[(Pi * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\pi}{2} + 2 \cdot \left(\cos^{-1} \left(\sqrt{0.5 - 0.5 \cdot x}\right) - \pi \cdot 0.5\right)
\end{array}
Initial program 7.2%
asin-acos8.8%
div-inv8.8%
metadata-eval8.8%
div-sub8.8%
metadata-eval8.8%
div-inv8.8%
metadata-eval8.8%
Applied egg-rr8.8%
Final simplification8.8%
(FPCore (x) :precision binary64 (- (/ PI 2.0) (* 2.0 (asin (sqrt (/ (- 1.0 x) 2.0))))))
double code(double x) {
return (((double) M_PI) / 2.0) - (2.0 * asin(sqrt(((1.0 - x) / 2.0))));
}
public static double code(double x) {
return (Math.PI / 2.0) - (2.0 * Math.asin(Math.sqrt(((1.0 - x) / 2.0))));
}
def code(x): return (math.pi / 2.0) - (2.0 * math.asin(math.sqrt(((1.0 - x) / 2.0))))
function code(x) return Float64(Float64(pi / 2.0) - Float64(2.0 * asin(sqrt(Float64(Float64(1.0 - x) / 2.0))))) end
function tmp = code(x) tmp = (pi / 2.0) - (2.0 * asin(sqrt(((1.0 - x) / 2.0)))); end
code[x_] := N[(N[(Pi / 2.0), $MachinePrecision] - N[(2.0 * N[ArcSin[N[Sqrt[N[(N[(1.0 - x), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\pi}{2} - 2 \cdot \sin^{-1} \left(\sqrt{\frac{1 - x}{2}}\right)
\end{array}
Initial program 7.2%
Final simplification7.2%
(FPCore (x) :precision binary64 (+ (* PI 0.5) (* 2.0 (asin (sqrt 0.5)))))
double code(double x) {
return (((double) M_PI) * 0.5) + (2.0 * asin(sqrt(0.5)));
}
public static double code(double x) {
return (Math.PI * 0.5) + (2.0 * Math.asin(Math.sqrt(0.5)));
}
def code(x): return (math.pi * 0.5) + (2.0 * math.asin(math.sqrt(0.5)))
function code(x) return Float64(Float64(pi * 0.5) + Float64(2.0 * asin(sqrt(0.5)))) end
function tmp = code(x) tmp = (pi * 0.5) + (2.0 * asin(sqrt(0.5))); end
code[x_] := N[(N[(Pi * 0.5), $MachinePrecision] + N[(2.0 * N[ArcSin[N[Sqrt[0.5], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\pi \cdot 0.5 + 2 \cdot \sin^{-1} \left(\sqrt{0.5}\right)
\end{array}
Initial program 7.2%
asin-acos8.8%
div-inv8.8%
metadata-eval8.8%
div-sub8.8%
metadata-eval8.8%
div-inv8.8%
metadata-eval8.8%
Applied egg-rr8.8%
div-inv8.8%
metadata-eval8.8%
cancel-sign-sub-inv8.8%
metadata-eval8.8%
metadata-eval8.8%
div-inv8.8%
asin-acos7.2%
*-commutative7.2%
add-sqr-sqrt0.0%
sqrt-unprod3.8%
swap-sqr3.8%
metadata-eval3.8%
metadata-eval3.8%
Applied egg-rr3.8%
Taylor expanded in x around 0 3.8%
Final simplification3.8%
(FPCore (x) :precision binary64 (- (/ PI 2.0) (* 2.0 (asin (sqrt 0.5)))))
double code(double x) {
return (((double) M_PI) / 2.0) - (2.0 * asin(sqrt(0.5)));
}
public static double code(double x) {
return (Math.PI / 2.0) - (2.0 * Math.asin(Math.sqrt(0.5)));
}
def code(x): return (math.pi / 2.0) - (2.0 * math.asin(math.sqrt(0.5)))
function code(x) return Float64(Float64(pi / 2.0) - Float64(2.0 * asin(sqrt(0.5)))) end
function tmp = code(x) tmp = (pi / 2.0) - (2.0 * asin(sqrt(0.5))); end
code[x_] := N[(N[(Pi / 2.0), $MachinePrecision] - N[(2.0 * N[ArcSin[N[Sqrt[0.5], $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\pi}{2} - 2 \cdot \sin^{-1} \left(\sqrt{0.5}\right)
\end{array}
Initial program 7.2%
Taylor expanded in x around 0 3.9%
Final simplification3.9%
(FPCore (x) :precision binary64 (asin x))
double code(double x) {
return asin(x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = asin(x)
end function
public static double code(double x) {
return Math.asin(x);
}
def code(x): return math.asin(x)
function code(x) return asin(x) end
function tmp = code(x) tmp = asin(x); end
code[x_] := N[ArcSin[x], $MachinePrecision]
\begin{array}{l}
\\
\sin^{-1} x
\end{array}
herbie shell --seed 2023271
(FPCore (x)
:name "Ian Simplification"
:precision binary64
:herbie-target
(asin x)
(- (/ PI 2.0) (* 2.0 (asin (sqrt (/ (- 1.0 x) 2.0))))))