
(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 6 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 77.3%
sub-neg77.3%
+-commutative77.3%
distribute-neg-frac277.3%
neg-sub077.3%
associate-+l-77.3%
neg-sub077.3%
remove-double-neg77.3%
distribute-neg-in77.3%
sub-neg77.3%
distribute-neg-frac277.3%
sub-neg77.3%
+-commutative77.3%
unsub-neg77.3%
sub-neg77.3%
+-commutative77.3%
unsub-neg77.3%
metadata-eval77.3%
Simplified77.3%
sub-neg77.3%
distribute-neg-frac77.3%
metadata-eval77.3%
Applied egg-rr77.3%
Simplified99.2%
associate-/r*99.8%
div-inv99.7%
Applied egg-rr99.7%
associate-*r/99.8%
*-rgt-identity99.8%
+-commutative99.8%
Simplified99.8%
(FPCore (x) :precision binary64 (if (<= x 0.75) 2.0 (/ (/ -2.0 x) (+ x -1.0))))
double code(double x) {
double tmp;
if (x <= 0.75) {
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 <= 0.75d0) 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 <= 0.75) {
tmp = 2.0;
} else {
tmp = (-2.0 / x) / (x + -1.0);
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.75: tmp = 2.0 else: tmp = (-2.0 / x) / (x + -1.0) return tmp
function code(x) tmp = 0.0 if (x <= 0.75) tmp = 2.0; else tmp = Float64(Float64(-2.0 / x) / Float64(x + -1.0)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= 0.75) tmp = 2.0; else tmp = (-2.0 / x) / (x + -1.0); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.75], 2.0, N[(N[(-2.0 / x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.75:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{-2}{x}}{x + -1}\\
\end{array}
\end{array}
if x < 0.75Initial program 81.5%
sub-neg81.5%
+-commutative81.5%
distribute-neg-frac281.5%
neg-sub081.5%
associate-+l-81.5%
neg-sub081.5%
remove-double-neg81.5%
distribute-neg-in81.5%
sub-neg81.5%
distribute-neg-frac281.5%
sub-neg81.5%
+-commutative81.5%
unsub-neg81.5%
sub-neg81.5%
+-commutative81.5%
unsub-neg81.5%
metadata-eval81.5%
Simplified81.5%
Taylor expanded in x around 0 66.7%
if 0.75 < x Initial program 62.9%
sub-neg62.9%
+-commutative62.9%
distribute-neg-frac262.9%
neg-sub062.9%
associate-+l-62.9%
neg-sub062.9%
remove-double-neg62.9%
distribute-neg-in62.9%
sub-neg62.9%
distribute-neg-frac262.9%
sub-neg62.9%
+-commutative62.9%
unsub-neg62.9%
sub-neg62.9%
+-commutative62.9%
unsub-neg62.9%
metadata-eval62.9%
Simplified62.9%
sub-neg62.9%
distribute-neg-frac62.9%
metadata-eval62.9%
Applied egg-rr62.9%
Simplified97.6%
associate-/r*99.8%
div-inv99.7%
Applied egg-rr99.7%
associate-*r/99.8%
*-rgt-identity99.8%
+-commutative99.8%
Simplified99.8%
Taylor expanded in x around inf 99.5%
(FPCore (x) :precision binary64 (if (<= x 0.75) 2.0 (/ -2.0 (* x (+ x -1.0)))))
double code(double x) {
double tmp;
if (x <= 0.75) {
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 <= 0.75d0) 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 <= 0.75) {
tmp = 2.0;
} else {
tmp = -2.0 / (x * (x + -1.0));
}
return tmp;
}
def code(x): tmp = 0 if x <= 0.75: tmp = 2.0 else: tmp = -2.0 / (x * (x + -1.0)) return tmp
function code(x) tmp = 0.0 if (x <= 0.75) 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 <= 0.75) tmp = 2.0; else tmp = -2.0 / (x * (x + -1.0)); end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 0.75], 2.0, N[(-2.0 / N[(x * N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.75:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{-2}{x \cdot \left(x + -1\right)}\\
\end{array}
\end{array}
if x < 0.75Initial program 81.5%
sub-neg81.5%
+-commutative81.5%
distribute-neg-frac281.5%
neg-sub081.5%
associate-+l-81.5%
neg-sub081.5%
remove-double-neg81.5%
distribute-neg-in81.5%
sub-neg81.5%
distribute-neg-frac281.5%
sub-neg81.5%
+-commutative81.5%
unsub-neg81.5%
sub-neg81.5%
+-commutative81.5%
unsub-neg81.5%
metadata-eval81.5%
Simplified81.5%
Taylor expanded in x around 0 66.7%
if 0.75 < x Initial program 62.9%
sub-neg62.9%
+-commutative62.9%
distribute-neg-frac262.9%
neg-sub062.9%
associate-+l-62.9%
neg-sub062.9%
remove-double-neg62.9%
distribute-neg-in62.9%
sub-neg62.9%
distribute-neg-frac262.9%
sub-neg62.9%
+-commutative62.9%
unsub-neg62.9%
sub-neg62.9%
+-commutative62.9%
unsub-neg62.9%
metadata-eval62.9%
Simplified62.9%
sub-neg62.9%
distribute-neg-frac62.9%
metadata-eval62.9%
Applied egg-rr62.9%
Simplified97.6%
Taylor expanded in x around inf 97.3%
(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 77.3%
sub-neg77.3%
+-commutative77.3%
distribute-neg-frac277.3%
neg-sub077.3%
associate-+l-77.3%
neg-sub077.3%
remove-double-neg77.3%
distribute-neg-in77.3%
sub-neg77.3%
distribute-neg-frac277.3%
sub-neg77.3%
+-commutative77.3%
unsub-neg77.3%
sub-neg77.3%
+-commutative77.3%
unsub-neg77.3%
metadata-eval77.3%
Simplified77.3%
sub-neg77.3%
distribute-neg-frac77.3%
metadata-eval77.3%
Applied egg-rr77.3%
Simplified99.2%
Final simplification99.2%
(FPCore (x) :precision binary64 (if (<= x 1.0) 2.0 (/ -1.0 x)))
double code(double x) {
double tmp;
if (x <= 1.0) {
tmp = 2.0;
} else {
tmp = -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 = (-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 = -1.0 / x;
}
return tmp;
}
def code(x): tmp = 0 if x <= 1.0: tmp = 2.0 else: tmp = -1.0 / x return tmp
function code(x) tmp = 0.0 if (x <= 1.0) tmp = 2.0; else tmp = 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 = -1.0 / x; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, 1.0], 2.0, N[(-1.0 / x), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{-1}{x}\\
\end{array}
\end{array}
if x < 1Initial program 81.5%
sub-neg81.5%
+-commutative81.5%
distribute-neg-frac281.5%
neg-sub081.5%
associate-+l-81.5%
neg-sub081.5%
remove-double-neg81.5%
distribute-neg-in81.5%
sub-neg81.5%
distribute-neg-frac281.5%
sub-neg81.5%
+-commutative81.5%
unsub-neg81.5%
sub-neg81.5%
+-commutative81.5%
unsub-neg81.5%
metadata-eval81.5%
Simplified81.5%
Taylor expanded in x around 0 66.7%
if 1 < x Initial program 62.9%
sub-neg62.9%
+-commutative62.9%
distribute-neg-frac262.9%
neg-sub062.9%
associate-+l-62.9%
neg-sub062.9%
remove-double-neg62.9%
distribute-neg-in62.9%
sub-neg62.9%
distribute-neg-frac262.9%
sub-neg62.9%
+-commutative62.9%
unsub-neg62.9%
sub-neg62.9%
+-commutative62.9%
unsub-neg62.9%
metadata-eval62.9%
Simplified62.9%
Taylor expanded in x around 0 2.8%
Taylor expanded in x around inf 2.8%
Taylor expanded in x around 0 6.7%
(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 77.3%
sub-neg77.3%
+-commutative77.3%
distribute-neg-frac277.3%
neg-sub077.3%
associate-+l-77.3%
neg-sub077.3%
remove-double-neg77.3%
distribute-neg-in77.3%
sub-neg77.3%
distribute-neg-frac277.3%
sub-neg77.3%
+-commutative77.3%
unsub-neg77.3%
sub-neg77.3%
+-commutative77.3%
unsub-neg77.3%
metadata-eval77.3%
Simplified77.3%
Taylor expanded in x around 0 52.2%
herbie shell --seed 2024181
(FPCore (x)
:name "Asymptote A"
:precision binary64
(- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))