
(FPCore (x) :precision binary64 (- (/ x (+ x 1.0)) (/ (+ x 1.0) (- x 1.0))))
double code(double x) {
return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x / (x + 1.0d0)) - ((x + 1.0d0) / (x - 1.0d0))
end function
public static double code(double x) {
return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
def code(x): return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0))
function code(x) return Float64(Float64(x / Float64(x + 1.0)) - Float64(Float64(x + 1.0) / Float64(x - 1.0))) end
function tmp = code(x) tmp = (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0)); end
code[x_] := N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x}{x + 1} - \frac{x + 1}{x - 1}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 6 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (- (/ x (+ x 1.0)) (/ (+ x 1.0) (- x 1.0))))
double code(double x) {
return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x / (x + 1.0d0)) - ((x + 1.0d0) / (x - 1.0d0))
end function
public static double code(double x) {
return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
def code(x): return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0))
function code(x) return Float64(Float64(x / Float64(x + 1.0)) - Float64(Float64(x + 1.0) / Float64(x - 1.0))) end
function tmp = code(x) tmp = (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0)); end
code[x_] := N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x}{x + 1} - \frac{x + 1}{x - 1}
\end{array}
(FPCore (x) :precision binary64 (if (<= (- (/ x (+ x 1.0)) (/ (+ x 1.0) (+ x -1.0))) 2e-5) (/ (+ -3.0 (/ (+ -1.0 (/ (+ -3.0 (/ -1.0 x)) x)) x)) x) (+ 1.0 (* x 3.0))))
double code(double x) {
double tmp;
if (((x / (x + 1.0)) - ((x + 1.0) / (x + -1.0))) <= 2e-5) {
tmp = (-3.0 + ((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x)) / x;
} else {
tmp = 1.0 + (x * 3.0);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (((x / (x + 1.0d0)) - ((x + 1.0d0) / (x + (-1.0d0)))) <= 2d-5) then
tmp = ((-3.0d0) + (((-1.0d0) + (((-3.0d0) + ((-1.0d0) / x)) / x)) / x)) / x
else
tmp = 1.0d0 + (x * 3.0d0)
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (((x / (x + 1.0)) - ((x + 1.0) / (x + -1.0))) <= 2e-5) {
tmp = (-3.0 + ((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x)) / x;
} else {
tmp = 1.0 + (x * 3.0);
}
return tmp;
}
def code(x): tmp = 0 if ((x / (x + 1.0)) - ((x + 1.0) / (x + -1.0))) <= 2e-5: tmp = (-3.0 + ((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x)) / x else: tmp = 1.0 + (x * 3.0) return tmp
function code(x) tmp = 0.0 if (Float64(Float64(x / Float64(x + 1.0)) - Float64(Float64(x + 1.0) / Float64(x + -1.0))) <= 2e-5) tmp = Float64(Float64(-3.0 + Float64(Float64(-1.0 + Float64(Float64(-3.0 + Float64(-1.0 / x)) / x)) / x)) / x); else tmp = Float64(1.0 + Float64(x * 3.0)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (((x / (x + 1.0)) - ((x + 1.0) / (x + -1.0))) <= 2e-5) tmp = (-3.0 + ((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x)) / x; else tmp = 1.0 + (x * 3.0); end tmp_2 = tmp; end
code[x_] := If[LessEqual[N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(N[(x + 1.0), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2e-5], N[(N[(-3.0 + N[(N[(-1.0 + N[(N[(-3.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision], N[(1.0 + N[(x * 3.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\frac{x}{x + 1} - \frac{x + 1}{x + -1} \leq 2 \cdot 10^{-5}:\\
\;\;\;\;\frac{-3 + \frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x}}{x}\\
\mathbf{else}:\\
\;\;\;\;1 + x \cdot 3\\
\end{array}
\end{array}
if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 2.00000000000000016e-5Initial program 8.0%
remove-double-neg8.0%
distribute-neg-frac8.0%
distribute-neg-in8.0%
sub-neg8.0%
distribute-frac-neg28.0%
sub-neg8.0%
+-commutative8.0%
unsub-neg8.0%
metadata-eval8.0%
neg-sub08.0%
associate-+l-8.0%
neg-sub08.0%
+-commutative8.0%
unsub-neg8.0%
Simplified8.0%
Taylor expanded in x around inf 100.0%
Simplified100.0%
if 2.00000000000000016e-5 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) Initial program 100.0%
remove-double-neg100.0%
distribute-neg-frac100.0%
distribute-neg-in100.0%
sub-neg100.0%
distribute-frac-neg2100.0%
sub-neg100.0%
+-commutative100.0%
unsub-neg100.0%
metadata-eval100.0%
neg-sub0100.0%
associate-+l-100.0%
neg-sub0100.0%
+-commutative100.0%
unsub-neg100.0%
Simplified100.0%
Taylor expanded in x around 0 100.0%
Final simplification100.0%
(FPCore (x) :precision binary64 (if (<= (- (/ x (+ x 1.0)) (/ (+ x 1.0) (+ x -1.0))) 2e-5) (/ (- -3.0 (/ (+ 1.0 (/ 3.0 x)) x)) x) (+ 1.0 (* x 3.0))))
double code(double x) {
double tmp;
if (((x / (x + 1.0)) - ((x + 1.0) / (x + -1.0))) <= 2e-5) {
tmp = (-3.0 - ((1.0 + (3.0 / x)) / x)) / x;
} else {
tmp = 1.0 + (x * 3.0);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (((x / (x + 1.0d0)) - ((x + 1.0d0) / (x + (-1.0d0)))) <= 2d-5) then
tmp = ((-3.0d0) - ((1.0d0 + (3.0d0 / x)) / x)) / x
else
tmp = 1.0d0 + (x * 3.0d0)
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (((x / (x + 1.0)) - ((x + 1.0) / (x + -1.0))) <= 2e-5) {
tmp = (-3.0 - ((1.0 + (3.0 / x)) / x)) / x;
} else {
tmp = 1.0 + (x * 3.0);
}
return tmp;
}
def code(x): tmp = 0 if ((x / (x + 1.0)) - ((x + 1.0) / (x + -1.0))) <= 2e-5: tmp = (-3.0 - ((1.0 + (3.0 / x)) / x)) / x else: tmp = 1.0 + (x * 3.0) return tmp
function code(x) tmp = 0.0 if (Float64(Float64(x / Float64(x + 1.0)) - Float64(Float64(x + 1.0) / Float64(x + -1.0))) <= 2e-5) tmp = Float64(Float64(-3.0 - Float64(Float64(1.0 + Float64(3.0 / x)) / x)) / x); else tmp = Float64(1.0 + Float64(x * 3.0)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (((x / (x + 1.0)) - ((x + 1.0) / (x + -1.0))) <= 2e-5) tmp = (-3.0 - ((1.0 + (3.0 / x)) / x)) / x; else tmp = 1.0 + (x * 3.0); end tmp_2 = tmp; end
code[x_] := If[LessEqual[N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(N[(x + 1.0), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2e-5], N[(N[(-3.0 - N[(N[(1.0 + N[(3.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision], N[(1.0 + N[(x * 3.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;\frac{x}{x + 1} - \frac{x + 1}{x + -1} \leq 2 \cdot 10^{-5}:\\
\;\;\;\;\frac{-3 - \frac{1 + \frac{3}{x}}{x}}{x}\\
\mathbf{else}:\\
\;\;\;\;1 + x \cdot 3\\
\end{array}
\end{array}
if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 2.00000000000000016e-5Initial program 8.0%
remove-double-neg8.0%
distribute-neg-frac8.0%
distribute-neg-in8.0%
sub-neg8.0%
distribute-frac-neg28.0%
sub-neg8.0%
+-commutative8.0%
unsub-neg8.0%
metadata-eval8.0%
neg-sub08.0%
associate-+l-8.0%
neg-sub08.0%
+-commutative8.0%
unsub-neg8.0%
Simplified8.0%
Taylor expanded in x around inf 99.8%
sub-neg99.8%
metadata-eval99.8%
+-commutative99.8%
mul-1-neg99.8%
unsub-neg99.8%
associate-*r/99.8%
metadata-eval99.8%
Simplified99.8%
if 2.00000000000000016e-5 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) Initial program 100.0%
remove-double-neg100.0%
distribute-neg-frac100.0%
distribute-neg-in100.0%
sub-neg100.0%
distribute-frac-neg2100.0%
sub-neg100.0%
+-commutative100.0%
unsub-neg100.0%
metadata-eval100.0%
neg-sub0100.0%
associate-+l-100.0%
neg-sub0100.0%
+-commutative100.0%
unsub-neg100.0%
Simplified100.0%
Taylor expanded in x around 0 100.0%
Final simplification99.9%
(FPCore (x) :precision binary64 (if (or (<= x -1.0) (not (<= x 1.0))) (/ (+ -3.0 (/ -1.0 x)) x) (+ 1.0 (* x 3.0))))
double code(double x) {
double tmp;
if ((x <= -1.0) || !(x <= 1.0)) {
tmp = (-3.0 + (-1.0 / x)) / x;
} else {
tmp = 1.0 + (x * 3.0);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if ((x <= (-1.0d0)) .or. (.not. (x <= 1.0d0))) then
tmp = ((-3.0d0) + ((-1.0d0) / x)) / x
else
tmp = 1.0d0 + (x * 3.0d0)
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if ((x <= -1.0) || !(x <= 1.0)) {
tmp = (-3.0 + (-1.0 / x)) / x;
} else {
tmp = 1.0 + (x * 3.0);
}
return tmp;
}
def code(x): tmp = 0 if (x <= -1.0) or not (x <= 1.0): tmp = (-3.0 + (-1.0 / x)) / x else: tmp = 1.0 + (x * 3.0) return tmp
function code(x) tmp = 0.0 if ((x <= -1.0) || !(x <= 1.0)) tmp = Float64(Float64(-3.0 + Float64(-1.0 / x)) / x); else tmp = Float64(1.0 + Float64(x * 3.0)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if ((x <= -1.0) || ~((x <= 1.0))) tmp = (-3.0 + (-1.0 / x)) / x; else tmp = 1.0 + (x * 3.0); end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -1.0], N[Not[LessEqual[x, 1.0]], $MachinePrecision]], N[(N[(-3.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision], N[(1.0 + N[(x * 3.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\
\;\;\;\;\frac{-3 + \frac{-1}{x}}{x}\\
\mathbf{else}:\\
\;\;\;\;1 + x \cdot 3\\
\end{array}
\end{array}
if x < -1 or 1 < x Initial program 8.0%
remove-double-neg8.0%
distribute-neg-frac8.0%
distribute-neg-in8.0%
sub-neg8.0%
distribute-frac-neg28.0%
sub-neg8.0%
+-commutative8.0%
unsub-neg8.0%
metadata-eval8.0%
neg-sub08.0%
associate-+l-8.0%
neg-sub08.0%
+-commutative8.0%
unsub-neg8.0%
Simplified8.0%
Taylor expanded in x around inf 99.5%
associate-*r/99.5%
distribute-lft-in99.5%
metadata-eval99.5%
neg-mul-199.5%
distribute-neg-frac99.5%
metadata-eval99.5%
Simplified99.5%
if -1 < x < 1Initial program 100.0%
remove-double-neg100.0%
distribute-neg-frac100.0%
distribute-neg-in100.0%
sub-neg100.0%
distribute-frac-neg2100.0%
sub-neg100.0%
+-commutative100.0%
unsub-neg100.0%
metadata-eval100.0%
neg-sub0100.0%
associate-+l-100.0%
neg-sub0100.0%
+-commutative100.0%
unsub-neg100.0%
Simplified100.0%
Taylor expanded in x around 0 100.0%
Final simplification99.7%
(FPCore (x) :precision binary64 (if (or (<= x -1.0) (not (<= x 1.0))) (/ -3.0 x) (+ 1.0 (* x 3.0))))
double code(double x) {
double tmp;
if ((x <= -1.0) || !(x <= 1.0)) {
tmp = -3.0 / x;
} else {
tmp = 1.0 + (x * 3.0);
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if ((x <= (-1.0d0)) .or. (.not. (x <= 1.0d0))) then
tmp = (-3.0d0) / x
else
tmp = 1.0d0 + (x * 3.0d0)
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if ((x <= -1.0) || !(x <= 1.0)) {
tmp = -3.0 / x;
} else {
tmp = 1.0 + (x * 3.0);
}
return tmp;
}
def code(x): tmp = 0 if (x <= -1.0) or not (x <= 1.0): tmp = -3.0 / x else: tmp = 1.0 + (x * 3.0) return tmp
function code(x) tmp = 0.0 if ((x <= -1.0) || !(x <= 1.0)) tmp = Float64(-3.0 / x); else tmp = Float64(1.0 + Float64(x * 3.0)); end return tmp end
function tmp_2 = code(x) tmp = 0.0; if ((x <= -1.0) || ~((x <= 1.0))) tmp = -3.0 / x; else tmp = 1.0 + (x * 3.0); end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -1.0], N[Not[LessEqual[x, 1.0]], $MachinePrecision]], N[(-3.0 / x), $MachinePrecision], N[(1.0 + N[(x * 3.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\
\;\;\;\;\frac{-3}{x}\\
\mathbf{else}:\\
\;\;\;\;1 + x \cdot 3\\
\end{array}
\end{array}
if x < -1 or 1 < x Initial program 8.0%
remove-double-neg8.0%
distribute-neg-frac8.0%
distribute-neg-in8.0%
sub-neg8.0%
distribute-frac-neg28.0%
sub-neg8.0%
+-commutative8.0%
unsub-neg8.0%
metadata-eval8.0%
neg-sub08.0%
associate-+l-8.0%
neg-sub08.0%
+-commutative8.0%
unsub-neg8.0%
Simplified8.0%
Taylor expanded in x around inf 98.4%
if -1 < x < 1Initial program 100.0%
remove-double-neg100.0%
distribute-neg-frac100.0%
distribute-neg-in100.0%
sub-neg100.0%
distribute-frac-neg2100.0%
sub-neg100.0%
+-commutative100.0%
unsub-neg100.0%
metadata-eval100.0%
neg-sub0100.0%
associate-+l-100.0%
neg-sub0100.0%
+-commutative100.0%
unsub-neg100.0%
Simplified100.0%
Taylor expanded in x around 0 100.0%
Final simplification99.2%
(FPCore (x) :precision binary64 (if (or (<= x -1.0) (not (<= x 1.0))) (/ -3.0 x) 1.0))
double code(double x) {
double tmp;
if ((x <= -1.0) || !(x <= 1.0)) {
tmp = -3.0 / x;
} else {
tmp = 1.0;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if ((x <= (-1.0d0)) .or. (.not. (x <= 1.0d0))) then
tmp = (-3.0d0) / x
else
tmp = 1.0d0
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if ((x <= -1.0) || !(x <= 1.0)) {
tmp = -3.0 / x;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x): tmp = 0 if (x <= -1.0) or not (x <= 1.0): tmp = -3.0 / x else: tmp = 1.0 return tmp
function code(x) tmp = 0.0 if ((x <= -1.0) || !(x <= 1.0)) tmp = Float64(-3.0 / x); else tmp = 1.0; end return tmp end
function tmp_2 = code(x) tmp = 0.0; if ((x <= -1.0) || ~((x <= 1.0))) tmp = -3.0 / x; else tmp = 1.0; end tmp_2 = tmp; end
code[x_] := If[Or[LessEqual[x, -1.0], N[Not[LessEqual[x, 1.0]], $MachinePrecision]], N[(-3.0 / x), $MachinePrecision], 1.0]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\
\;\;\;\;\frac{-3}{x}\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -1 or 1 < x Initial program 8.0%
remove-double-neg8.0%
distribute-neg-frac8.0%
distribute-neg-in8.0%
sub-neg8.0%
distribute-frac-neg28.0%
sub-neg8.0%
+-commutative8.0%
unsub-neg8.0%
metadata-eval8.0%
neg-sub08.0%
associate-+l-8.0%
neg-sub08.0%
+-commutative8.0%
unsub-neg8.0%
Simplified8.0%
Taylor expanded in x around inf 98.4%
if -1 < x < 1Initial program 100.0%
remove-double-neg100.0%
distribute-neg-frac100.0%
distribute-neg-in100.0%
sub-neg100.0%
distribute-frac-neg2100.0%
sub-neg100.0%
+-commutative100.0%
unsub-neg100.0%
metadata-eval100.0%
neg-sub0100.0%
associate-+l-100.0%
neg-sub0100.0%
+-commutative100.0%
unsub-neg100.0%
Simplified100.0%
Taylor expanded in x around 0 99.7%
Final simplification99.1%
(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 55.1%
remove-double-neg55.1%
distribute-neg-frac55.1%
distribute-neg-in55.1%
sub-neg55.1%
distribute-frac-neg255.1%
sub-neg55.1%
+-commutative55.1%
unsub-neg55.1%
metadata-eval55.1%
neg-sub055.1%
associate-+l-55.1%
neg-sub055.1%
+-commutative55.1%
unsub-neg55.1%
Simplified55.1%
Taylor expanded in x around 0 52.9%
Final simplification52.9%
herbie shell --seed 2024067
(FPCore (x)
:name "Asymptote C"
:precision binary64
(- (/ x (+ x 1.0)) (/ (+ x 1.0) (- x 1.0))))