
(FPCore (x) :precision binary64 (log (+ (/ 1.0 x) (/ (sqrt (- 1.0 (* x x))) x))))
double code(double x) {
return log(((1.0 / x) + (sqrt((1.0 - (x * x))) / x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = log(((1.0d0 / x) + (sqrt((1.0d0 - (x * x))) / x)))
end function
public static double code(double x) {
return Math.log(((1.0 / x) + (Math.sqrt((1.0 - (x * x))) / x)));
}
def code(x): return math.log(((1.0 / x) + (math.sqrt((1.0 - (x * x))) / x)))
function code(x) return log(Float64(Float64(1.0 / x) + Float64(sqrt(Float64(1.0 - Float64(x * x))) / x))) end
function tmp = code(x) tmp = log(((1.0 / x) + (sqrt((1.0 - (x * x))) / x))); end
code[x_] := N[Log[N[(N[(1.0 / x), $MachinePrecision] + N[(N[Sqrt[N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\log \left(\frac{1}{x} + \frac{\sqrt{1 - x \cdot x}}{x}\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (log (+ (/ 1.0 x) (/ (sqrt (- 1.0 (* x x))) x))))
double code(double x) {
return log(((1.0 / x) + (sqrt((1.0 - (x * x))) / x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = log(((1.0d0 / x) + (sqrt((1.0d0 - (x * x))) / x)))
end function
public static double code(double x) {
return Math.log(((1.0 / x) + (Math.sqrt((1.0 - (x * x))) / x)));
}
def code(x): return math.log(((1.0 / x) + (math.sqrt((1.0 - (x * x))) / x)))
function code(x) return log(Float64(Float64(1.0 / x) + Float64(sqrt(Float64(1.0 - Float64(x * x))) / x))) end
function tmp = code(x) tmp = log(((1.0 / x) + (sqrt((1.0 - (x * x))) / x))); end
code[x_] := N[Log[N[(N[(1.0 / x), $MachinePrecision] + N[(N[Sqrt[N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\log \left(\frac{1}{x} + \frac{\sqrt{1 - x \cdot x}}{x}\right)
\end{array}
(FPCore (x) :precision binary64 (log (+ (pow x -1.0) (/ (sqrt (- 1.0 (* x x))) x))))
double code(double x) {
return log((pow(x, -1.0) + (sqrt((1.0 - (x * x))) / x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = log(((x ** (-1.0d0)) + (sqrt((1.0d0 - (x * x))) / x)))
end function
public static double code(double x) {
return Math.log((Math.pow(x, -1.0) + (Math.sqrt((1.0 - (x * x))) / x)));
}
def code(x): return math.log((math.pow(x, -1.0) + (math.sqrt((1.0 - (x * x))) / x)))
function code(x) return log(Float64((x ^ -1.0) + Float64(sqrt(Float64(1.0 - Float64(x * x))) / x))) end
function tmp = code(x) tmp = log(((x ^ -1.0) + (sqrt((1.0 - (x * x))) / x))); end
code[x_] := N[Log[N[(N[Power[x, -1.0], $MachinePrecision] + N[(N[Sqrt[N[(1.0 - N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\log \left({x}^{-1} + \frac{\sqrt{1 - x \cdot x}}{x}\right)
\end{array}
Initial program 100.0%
Final simplification100.0%
(FPCore (x) :precision binary64 (log (fma (fma -0.125 (* x x) -0.5) x (/ 2.0 x))))
double code(double x) {
return log(fma(fma(-0.125, (x * x), -0.5), x, (2.0 / x)));
}
function code(x) return log(fma(fma(-0.125, Float64(x * x), -0.5), x, Float64(2.0 / x))) end
code[x_] := N[Log[N[(N[(-0.125 * N[(x * x), $MachinePrecision] + -0.5), $MachinePrecision] * x + N[(2.0 / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\log \left(\mathsf{fma}\left(\mathsf{fma}\left(-0.125, x \cdot x, -0.5\right), x, \frac{2}{x}\right)\right)
\end{array}
Initial program 100.0%
Taylor expanded in x around 0
+-commutativeN/A
div-addN/A
*-commutativeN/A
associate-/l*N/A
unpow2N/A
associate-/l*N/A
*-inversesN/A
*-rgt-identityN/A
lower-fma.f64N/A
lower--.f64N/A
lower-*.f64N/A
unpow2N/A
lower-*.f64N/A
lower-/.f6499.8
Applied rewrites99.8%
Taylor expanded in x around 0
Applied rewrites99.8%
(FPCore (x) :precision binary64 (log (fma -0.5 x (/ 2.0 x))))
double code(double x) {
return log(fma(-0.5, x, (2.0 / x)));
}
function code(x) return log(fma(-0.5, x, Float64(2.0 / x))) end
code[x_] := N[Log[N[(-0.5 * x + N[(2.0 / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\log \left(\mathsf{fma}\left(-0.5, x, \frac{2}{x}\right)\right)
\end{array}
Initial program 100.0%
Taylor expanded in x around 0
+-commutativeN/A
div-addN/A
associate-/l*N/A
unpow2N/A
associate-/l*N/A
*-inversesN/A
*-rgt-identityN/A
lower-fma.f64N/A
lower-/.f6499.6
Applied rewrites99.6%
(FPCore (x) :precision binary64 (log (/ 2.0 x)))
double code(double x) {
return log((2.0 / x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = log((2.0d0 / x))
end function
public static double code(double x) {
return Math.log((2.0 / x));
}
def code(x): return math.log((2.0 / x))
function code(x) return log(Float64(2.0 / x)) end
function tmp = code(x) tmp = log((2.0 / x)); end
code[x_] := N[Log[N[(2.0 / x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\log \left(\frac{2}{x}\right)
\end{array}
Initial program 100.0%
Taylor expanded in x around 0
lower-/.f6499.0
Applied rewrites99.0%
(FPCore (x) :precision binary64 (log (* -0.5 x)))
double code(double x) {
return log((-0.5 * x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = log(((-0.5d0) * x))
end function
public static double code(double x) {
return Math.log((-0.5 * x));
}
def code(x): return math.log((-0.5 * x))
function code(x) return log(Float64(-0.5 * x)) end
function tmp = code(x) tmp = log((-0.5 * x)); end
code[x_] := N[Log[N[(-0.5 * x), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}
\\
\log \left(-0.5 \cdot x\right)
\end{array}
Initial program 100.0%
Taylor expanded in x around 0
+-commutativeN/A
div-addN/A
associate-/l*N/A
unpow2N/A
associate-/l*N/A
*-inversesN/A
*-rgt-identityN/A
lower-fma.f64N/A
lower-/.f6499.6
Applied rewrites99.6%
Taylor expanded in x around inf
Applied rewrites0.0%
herbie shell --seed 2024326
(FPCore (x)
:name "Hyperbolic arc-(co)secant"
:precision binary64
(log (+ (/ 1.0 x) (/ (sqrt (- 1.0 (* x x))) x))))