
(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)) (+ x -1.0)))
double code(double x) {
return (-2.0 / (1.0 + x)) / (x + -1.0);
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((-2.0d0) / (1.0d0 + x)) / (x + (-1.0d0))
end function
public static double code(double x) {
return (-2.0 / (1.0 + x)) / (x + -1.0);
}
def code(x): return (-2.0 / (1.0 + x)) / (x + -1.0)
function code(x) return Float64(Float64(-2.0 / Float64(1.0 + x)) / Float64(x + -1.0)) end
function tmp = code(x) tmp = (-2.0 / (1.0 + x)) / (x + -1.0); end
code[x_] := N[(N[(-2.0 / N[(1.0 + x), $MachinePrecision]), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{-2}{1 + x}}{x + -1}
\end{array}
Initial program 80.0%
sub-neg80.0%
+-commutative80.0%
distribute-neg-frac280.0%
neg-sub080.0%
associate-+l-80.0%
neg-sub080.0%
remove-double-neg80.0%
distribute-neg-in80.0%
sub-neg80.0%
distribute-neg-frac280.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
metadata-eval80.0%
Simplified80.0%
sub-neg80.0%
distribute-neg-frac80.0%
metadata-eval80.0%
Applied egg-rr80.0%
Simplified99.3%
associate-/r*99.9%
div-inv99.8%
+-commutative99.8%
Applied egg-rr99.8%
un-div-inv99.9%
Applied egg-rr99.9%
(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(Float64(2.0 / 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[(N[(2.0 / x), $MachinePrecision] / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{2}{x}}{-1 - x}\\
\end{array}
\end{array}
if x < 1Initial program 86.2%
sub-neg86.2%
+-commutative86.2%
distribute-neg-frac286.2%
neg-sub086.2%
associate-+l-86.2%
neg-sub086.2%
remove-double-neg86.2%
distribute-neg-in86.2%
sub-neg86.2%
distribute-neg-frac286.2%
sub-neg86.2%
+-commutative86.2%
unsub-neg86.2%
sub-neg86.2%
+-commutative86.2%
unsub-neg86.2%
metadata-eval86.2%
Simplified86.2%
Taylor expanded in x around 0 66.2%
if 1 < x Initial program 58.5%
sub-neg58.5%
+-commutative58.5%
distribute-neg-frac258.5%
neg-sub058.5%
associate-+l-58.5%
neg-sub058.5%
remove-double-neg58.5%
distribute-neg-in58.5%
sub-neg58.5%
distribute-neg-frac258.5%
sub-neg58.5%
+-commutative58.5%
unsub-neg58.5%
sub-neg58.5%
+-commutative58.5%
unsub-neg58.5%
metadata-eval58.5%
Simplified58.5%
frac-sub60.9%
*-rgt-identity60.9%
metadata-eval60.9%
div-inv60.9%
associate-/r*60.9%
metadata-eval60.9%
div-inv60.9%
*-un-lft-identity60.9%
associate--l-66.4%
div-inv66.4%
metadata-eval66.4%
*-rgt-identity66.4%
div-inv66.4%
metadata-eval66.4%
*-rgt-identity66.4%
Applied egg-rr66.4%
Taylor expanded in x around inf 97.1%
(FPCore (x) :precision binary64 (if (<= x 0.76) 2.0 (/ -2.0 (* x (+ x -1.0)))))
double code(double x) {
double tmp;
if (x <= 0.76) {
tmp = 2.0;
} else {
tmp = -2.0 / (x * (x + -1.0));
}
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 * (x + (-1.0d0)))
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 * (x + -1.0));
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.76: tmp = 2.0 else: tmp = -2.0 / (x * (x + -1.0)) return tmp
function code(x) tmp = 0.0 if (x <= 0.76) tmp = 2.0; else tmp = Float64(-2.0 / Float64(x * Float64(x + -1.0))); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 0.76) tmp = 2.0; else tmp = -2.0 / (x * (x + -1.0)); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.76], 2.0, N[(-2.0 / N[(x * N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.76:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{-2}{x \cdot \left(x + -1\right)}\\
\end{array}
\end{array}
if x < 0.76000000000000001Initial program 86.2%
sub-neg86.2%
+-commutative86.2%
distribute-neg-frac286.2%
neg-sub086.2%
associate-+l-86.2%
neg-sub086.2%
remove-double-neg86.2%
distribute-neg-in86.2%
sub-neg86.2%
distribute-neg-frac286.2%
sub-neg86.2%
+-commutative86.2%
unsub-neg86.2%
sub-neg86.2%
+-commutative86.2%
unsub-neg86.2%
metadata-eval86.2%
Simplified86.2%
Taylor expanded in x around 0 66.2%
if 0.76000000000000001 < x Initial program 58.5%
sub-neg58.5%
+-commutative58.5%
distribute-neg-frac258.5%
neg-sub058.5%
associate-+l-58.5%
neg-sub058.5%
remove-double-neg58.5%
distribute-neg-in58.5%
sub-neg58.5%
distribute-neg-frac258.5%
sub-neg58.5%
+-commutative58.5%
unsub-neg58.5%
sub-neg58.5%
+-commutative58.5%
unsub-neg58.5%
metadata-eval58.5%
Simplified58.5%
sub-neg58.5%
distribute-neg-frac58.5%
metadata-eval58.5%
Applied egg-rr58.5%
Simplified99.0%
Taylor expanded in x around inf 96.2%
(FPCore (x) :precision binary64 (/ -2.0 (* (+ x -1.0) (+ 1.0 x))))
double code(double x) {
return -2.0 / ((x + -1.0) * (1.0 + x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-2.0d0) / ((x + (-1.0d0)) * (1.0d0 + x))
end function
public static double code(double x) {
return -2.0 / ((x + -1.0) * (1.0 + x));
}
def code(x): return -2.0 / ((x + -1.0) * (1.0 + x))
function code(x) return Float64(-2.0 / Float64(Float64(x + -1.0) * Float64(1.0 + x))) end
function tmp = code(x) tmp = -2.0 / ((x + -1.0) * (1.0 + x)); end
code[x_] := N[(-2.0 / N[(N[(x + -1.0), $MachinePrecision] * N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-2}{\left(x + -1\right) \cdot \left(1 + x\right)}
\end{array}
Initial program 80.0%
sub-neg80.0%
+-commutative80.0%
distribute-neg-frac280.0%
neg-sub080.0%
associate-+l-80.0%
neg-sub080.0%
remove-double-neg80.0%
distribute-neg-in80.0%
sub-neg80.0%
distribute-neg-frac280.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
metadata-eval80.0%
Simplified80.0%
sub-neg80.0%
distribute-neg-frac80.0%
metadata-eval80.0%
Applied egg-rr80.0%
Simplified99.3%
Final simplification99.3%
(FPCore (x) :precision binary64 (/ -2.0 (+ x -1.0)))
double code(double x) {
return -2.0 / (x + -1.0);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-2.0d0) / (x + (-1.0d0))
end function
public static double code(double x) {
return -2.0 / (x + -1.0);
}
def code(x): return -2.0 / (x + -1.0)
function code(x) return Float64(-2.0 / Float64(x + -1.0)) end
function tmp = code(x) tmp = -2.0 / (x + -1.0); end
code[x_] := N[(-2.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-2}{x + -1}
\end{array}
Initial program 80.0%
sub-neg80.0%
+-commutative80.0%
distribute-neg-frac280.0%
neg-sub080.0%
associate-+l-80.0%
neg-sub080.0%
remove-double-neg80.0%
distribute-neg-in80.0%
sub-neg80.0%
distribute-neg-frac280.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
metadata-eval80.0%
Simplified80.0%
sub-neg80.0%
distribute-neg-frac80.0%
metadata-eval80.0%
Applied egg-rr80.0%
Simplified99.3%
associate-/r*99.9%
div-inv99.8%
+-commutative99.8%
Applied egg-rr99.8%
un-div-inv99.9%
Applied egg-rr99.9%
Taylor expanded in x around 0 53.1%
(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}
Initial program 80.0%
sub-neg80.0%
+-commutative80.0%
distribute-neg-frac280.0%
neg-sub080.0%
associate-+l-80.0%
neg-sub080.0%
remove-double-neg80.0%
distribute-neg-in80.0%
sub-neg80.0%
distribute-neg-frac280.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
metadata-eval80.0%
Simplified80.0%
Taylor expanded in x around 0 52.1%
(FPCore (x) :precision binary64 1.0)
double code(double x) {
return 1.0;
}
real(8) function code(x)
real(8), intent (in) :: x
code = 1.0d0
end function
public static double code(double x) {
return 1.0;
}
def code(x): return 1.0
function code(x) return 1.0 end
function tmp = code(x) tmp = 1.0; end
code[x_] := 1.0
\begin{array}{l}
\\
1
\end{array}
Initial program 80.0%
sub-neg80.0%
+-commutative80.0%
distribute-neg-frac280.0%
neg-sub080.0%
associate-+l-80.0%
neg-sub080.0%
remove-double-neg80.0%
distribute-neg-in80.0%
sub-neg80.0%
distribute-neg-frac280.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
sub-neg80.0%
+-commutative80.0%
unsub-neg80.0%
metadata-eval80.0%
Simplified80.0%
Taylor expanded in x around 0 51.4%
Taylor expanded in x around inf 10.9%
herbie shell --seed 2024148
(FPCore (x)
:name "Asymptote A"
:precision binary64
(- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))