
(FPCore (x) :precision binary64 (- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))
double code(double x) {
return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x + 1.0d0)) - (1.0d0 / (x - 1.0d0))
end function
public static double code(double x) {
return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0));
}
def code(x): return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0))
function code(x) return Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(1.0 / Float64(x - 1.0))) end
function tmp = code(x) tmp = (1.0 / (x + 1.0)) - (1.0 / (x - 1.0)); end
code[x_] := N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x + 1} - \frac{1}{x - 1}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))
double code(double x) {
return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x + 1.0d0)) - (1.0d0 / (x - 1.0d0))
end function
public static double code(double x) {
return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0));
}
def code(x): return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0))
function code(x) return Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(1.0 / Float64(x - 1.0))) end
function tmp = code(x) tmp = (1.0 / (x + 1.0)) - (1.0 / (x - 1.0)); end
code[x_] := N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x + 1} - \frac{1}{x - 1}
\end{array}
(FPCore (x) :precision binary64 (/ (/ 2.0 (- -1.0 x)) (+ -1.0 x)))
double code(double x) {
return (2.0 / (-1.0 - x)) / (-1.0 + x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (2.0d0 / ((-1.0d0) - x)) / ((-1.0d0) + x)
end function
public static double code(double x) {
return (2.0 / (-1.0 - x)) / (-1.0 + x);
}
def code(x): return (2.0 / (-1.0 - x)) / (-1.0 + x)
function code(x) return Float64(Float64(2.0 / Float64(-1.0 - x)) / Float64(-1.0 + x)) end
function tmp = code(x) tmp = (2.0 / (-1.0 - x)) / (-1.0 + x); end
code[x_] := N[(N[(2.0 / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision] / N[(-1.0 + x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{2}{-1 - x}}{-1 + x}
\end{array}
(FPCore (x) :precision binary64 (if (<= x 1.0) 2.0 (/ 2.0 (* x (- -1.0 x)))))
double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 2.0;
} else {
tmp = 2.0 / (x * (-1.0 - x));
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 1.0d0) then
tmp = 2.0d0
else
tmp = 2.0d0 / (x * ((-1.0d0) - x))
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 2.0;
} else {
tmp = 2.0 / (x * (-1.0 - x));
}
return tmp;
}
def code(x): tmp = 0 if x <= 1.0: tmp = 2.0 else: tmp = 2.0 / (x * (-1.0 - x)) return tmp
function code(x) tmp = 0.0 if (x <= 1.0) tmp = 2.0; else tmp = Float64(2.0 / Float64(x * Float64(-1.0 - x))); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 1.0) tmp = 2.0; else tmp = 2.0 / (x * (-1.0 - x)); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 1.0], 2.0, N[(2.0 / N[(x * N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{2}{x \cdot \left(-1 - x\right)}\\
\end{array}
\end{array}
(FPCore (x) :precision binary64 (if (<= x 0.76) 2.0 (/ (/ -2.0 x) (+ -1.0 x))))
double code(double x) {
double tmp;
if (x <= 0.76) {
tmp = 2.0;
} else {
tmp = (-2.0 / x) / (-1.0 + x);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 0.76d0) then
tmp = 2.0d0
else
tmp = ((-2.0d0) / x) / ((-1.0d0) + x)
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 0.76) {
tmp = 2.0;
} else {
tmp = (-2.0 / x) / (-1.0 + x);
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.76: tmp = 2.0 else: tmp = (-2.0 / x) / (-1.0 + x) return tmp
function code(x) tmp = 0.0 if (x <= 0.76) tmp = 2.0; else tmp = Float64(Float64(-2.0 / x) / Float64(-1.0 + x)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 0.76) tmp = 2.0; else tmp = (-2.0 / x) / (-1.0 + x); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.76], 2.0, N[(N[(-2.0 / x), $MachinePrecision] / N[(-1.0 + x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.76:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{-2}{x}}{-1 + x}\\
\end{array}
\end{array}
(FPCore (x) :precision binary64 (/ 2.0 (* (- -1.0 x) (+ -1.0 x))))
double code(double x) {
return 2.0 / ((-1.0 - x) * (-1.0 + x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / (((-1.0d0) - x) * ((-1.0d0) + x))
end function
public static double code(double x) {
return 2.0 / ((-1.0 - x) * (-1.0 + x));
}
def code(x): return 2.0 / ((-1.0 - x) * (-1.0 + x))
function code(x) return Float64(2.0 / Float64(Float64(-1.0 - x) * Float64(-1.0 + x))) end
function tmp = code(x) tmp = 2.0 / ((-1.0 - x) * (-1.0 + x)); end
code[x_] := N[(2.0 / N[(N[(-1.0 - x), $MachinePrecision] * N[(-1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{\left(-1 - x\right) \cdot \left(-1 + x\right)}
\end{array}
(FPCore (x) :precision binary64 (if (<= x 1.0) 2.0 (/ -2.0 x)))
double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 2.0;
} else {
tmp = -2.0 / x;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= 1.0d0) then
tmp = 2.0d0
else
tmp = (-2.0d0) / x
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 2.0;
} else {
tmp = -2.0 / x;
}
return tmp;
}
def code(x): tmp = 0 if x <= 1.0: tmp = 2.0 else: tmp = -2.0 / x return tmp
function code(x) tmp = 0.0 if (x <= 1.0) tmp = 2.0; else tmp = Float64(-2.0 / x); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 1.0) tmp = 2.0; else tmp = -2.0 / x; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 1.0], 2.0, N[(-2.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{-2}{x}\\
\end{array}
\end{array}
(FPCore (x) :precision binary64 (/ -2.0 (+ -1.0 x)))
double code(double x) {
return -2.0 / (-1.0 + x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-2.0d0) / ((-1.0d0) + x)
end function
public static double code(double x) {
return -2.0 / (-1.0 + x);
}
def code(x): return -2.0 / (-1.0 + x)
function code(x) return Float64(-2.0 / Float64(-1.0 + x)) end
function tmp = code(x) tmp = -2.0 / (-1.0 + x); end
code[x_] := N[(-2.0 / N[(-1.0 + x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-2}{-1 + x}
\end{array}
(FPCore (x) :precision binary64 2.0)
double code(double x) {
return 2.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0
end function
public static double code(double x) {
return 2.0;
}
def code(x): return 2.0
function code(x) return 2.0 end
function tmp = code(x) tmp = 2.0; end
code[x_] := 2.0
\begin{array}{l}
\\
2
\end{array}
herbie shell --seed 2023364
(FPCore (x)
:name "Asymptote A"
:precision binary64
(- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))