
(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}
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (/ (/ 2.0 (+ x_m -1.0)) (- -1.0 x_m)))
x_m = fabs(x);
double code(double x_m) {
return (2.0 / (x_m + -1.0)) / (-1.0 - x_m);
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = (2.0d0 / (x_m + (-1.0d0))) / ((-1.0d0) - x_m)
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return (2.0 / (x_m + -1.0)) / (-1.0 - x_m);
}
x_m = math.fabs(x) def code(x_m): return (2.0 / (x_m + -1.0)) / (-1.0 - x_m)
x_m = abs(x) function code(x_m) return Float64(Float64(2.0 / Float64(x_m + -1.0)) / Float64(-1.0 - x_m)) end
x_m = abs(x); function tmp = code(x_m) tmp = (2.0 / (x_m + -1.0)) / (-1.0 - x_m); end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := N[(N[(2.0 / N[(x$95$m + -1.0), $MachinePrecision]), $MachinePrecision] / N[(-1.0 - x$95$m), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
\frac{\frac{2}{x\_m + -1}}{-1 - x\_m}
\end{array}
Initial program 77.1%
sub-neg77.1%
+-commutative77.1%
distribute-neg-frac277.1%
neg-sub077.1%
associate-+l-77.1%
neg-sub077.1%
remove-double-neg77.1%
distribute-neg-in77.1%
sub-neg77.1%
distribute-neg-frac277.1%
sub-neg77.1%
+-commutative77.1%
unsub-neg77.1%
sub-neg77.1%
+-commutative77.1%
unsub-neg77.1%
metadata-eval77.1%
Simplified77.1%
frac-sub77.2%
*-rgt-identity77.2%
metadata-eval77.2%
div-inv77.2%
associate-/r*77.2%
metadata-eval77.2%
div-inv77.2%
*-un-lft-identity77.2%
associate--l-80.3%
div-inv80.3%
metadata-eval80.3%
*-rgt-identity80.3%
div-inv80.3%
metadata-eval80.3%
*-rgt-identity80.3%
Applied egg-rr80.3%
*-un-lft-identity80.3%
associate--r+77.2%
sub-neg77.2%
flip--57.2%
+-commutative57.2%
distribute-neg-frac257.2%
metadata-eval57.2%
metadata-eval57.2%
mul-1-neg57.2%
+-commutative57.2%
distribute-lft-in57.2%
metadata-eval57.2%
neg-mul-157.2%
sub-neg57.2%
flip-+77.2%
+-commutative77.2%
Applied egg-rr77.2%
*-lft-identity77.2%
sub-neg77.2%
+-commutative77.2%
metadata-eval77.2%
distribute-neg-in77.2%
distribute-neg-frac277.2%
distribute-neg-frac77.2%
associate-+l-80.3%
sub-neg80.3%
distribute-neg-in80.3%
metadata-eval80.3%
+-commutative80.3%
sub-neg80.3%
+-commutative80.3%
associate--r-99.9%
+-inverses99.9%
metadata-eval99.9%
metadata-eval99.9%
metadata-eval99.9%
Simplified99.9%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (if (<= x_m 1.0) 2.0 (/ (/ 2.0 x_m) (- -1.0 x_m))))
x_m = fabs(x);
double code(double x_m) {
double tmp;
if (x_m <= 1.0) {
tmp = 2.0;
} else {
tmp = (2.0 / x_m) / (-1.0 - x_m);
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 1.0d0) then
tmp = 2.0d0
else
tmp = (2.0d0 / x_m) / ((-1.0d0) - x_m)
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double tmp;
if (x_m <= 1.0) {
tmp = 2.0;
} else {
tmp = (2.0 / x_m) / (-1.0 - x_m);
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): tmp = 0 if x_m <= 1.0: tmp = 2.0 else: tmp = (2.0 / x_m) / (-1.0 - x_m) return tmp
x_m = abs(x) function code(x_m) tmp = 0.0 if (x_m <= 1.0) tmp = 2.0; else tmp = Float64(Float64(2.0 / x_m) / Float64(-1.0 - x_m)); end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) tmp = 0.0; if (x_m <= 1.0) tmp = 2.0; else tmp = (2.0 / x_m) / (-1.0 - x_m); end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := If[LessEqual[x$95$m, 1.0], 2.0, N[(N[(2.0 / x$95$m), $MachinePrecision] / N[(-1.0 - x$95$m), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 1:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{2}{x\_m}}{-1 - x\_m}\\
\end{array}
\end{array}
if x < 1Initial program 82.8%
sub-neg82.8%
+-commutative82.8%
distribute-neg-frac282.8%
neg-sub082.8%
associate-+l-82.8%
neg-sub082.8%
remove-double-neg82.8%
distribute-neg-in82.8%
sub-neg82.8%
distribute-neg-frac282.8%
sub-neg82.8%
+-commutative82.8%
unsub-neg82.8%
sub-neg82.8%
+-commutative82.8%
unsub-neg82.8%
metadata-eval82.8%
Simplified82.8%
Taylor expanded in x around 0 69.3%
if 1 < x Initial program 55.6%
sub-neg55.6%
+-commutative55.6%
distribute-neg-frac255.6%
neg-sub055.6%
associate-+l-55.6%
neg-sub055.6%
remove-double-neg55.6%
distribute-neg-in55.6%
sub-neg55.6%
distribute-neg-frac255.6%
sub-neg55.6%
+-commutative55.6%
unsub-neg55.6%
sub-neg55.6%
+-commutative55.6%
unsub-neg55.6%
metadata-eval55.6%
Simplified55.6%
frac-sub56.2%
*-rgt-identity56.2%
metadata-eval56.2%
div-inv56.2%
associate-/r*56.3%
metadata-eval56.3%
div-inv56.3%
*-un-lft-identity56.3%
associate--l-62.4%
div-inv62.4%
metadata-eval62.4%
*-rgt-identity62.4%
div-inv62.4%
metadata-eval62.4%
*-rgt-identity62.4%
Applied egg-rr62.4%
Taylor expanded in x around inf 99.0%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (if (<= x_m 0.75) 2.0 (/ -2.0 (* x_m (+ x_m -1.0)))))
x_m = fabs(x);
double code(double x_m) {
double tmp;
if (x_m <= 0.75) {
tmp = 2.0;
} else {
tmp = -2.0 / (x_m * (x_m + -1.0));
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 0.75d0) then
tmp = 2.0d0
else
tmp = (-2.0d0) / (x_m * (x_m + (-1.0d0)))
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double tmp;
if (x_m <= 0.75) {
tmp = 2.0;
} else {
tmp = -2.0 / (x_m * (x_m + -1.0));
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): tmp = 0 if x_m <= 0.75: tmp = 2.0 else: tmp = -2.0 / (x_m * (x_m + -1.0)) return tmp
x_m = abs(x) function code(x_m) tmp = 0.0 if (x_m <= 0.75) tmp = 2.0; else tmp = Float64(-2.0 / Float64(x_m * Float64(x_m + -1.0))); end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) tmp = 0.0; if (x_m <= 0.75) tmp = 2.0; else tmp = -2.0 / (x_m * (x_m + -1.0)); end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := If[LessEqual[x$95$m, 0.75], 2.0, N[(-2.0 / N[(x$95$m * N[(x$95$m + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 0.75:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{-2}{x\_m \cdot \left(x\_m + -1\right)}\\
\end{array}
\end{array}
if x < 0.75Initial program 82.8%
sub-neg82.8%
+-commutative82.8%
distribute-neg-frac282.8%
neg-sub082.8%
associate-+l-82.8%
neg-sub082.8%
remove-double-neg82.8%
distribute-neg-in82.8%
sub-neg82.8%
distribute-neg-frac282.8%
sub-neg82.8%
+-commutative82.8%
unsub-neg82.8%
sub-neg82.8%
+-commutative82.8%
unsub-neg82.8%
metadata-eval82.8%
Simplified82.8%
Taylor expanded in x around 0 69.3%
if 0.75 < x Initial program 55.6%
sub-neg55.6%
+-commutative55.6%
distribute-neg-frac255.6%
neg-sub055.6%
associate-+l-55.6%
neg-sub055.6%
remove-double-neg55.6%
distribute-neg-in55.6%
sub-neg55.6%
distribute-neg-frac255.6%
sub-neg55.6%
+-commutative55.6%
unsub-neg55.6%
sub-neg55.6%
+-commutative55.6%
unsub-neg55.6%
metadata-eval55.6%
Simplified55.6%
sub-neg55.6%
distribute-neg-frac55.6%
metadata-eval55.6%
Applied egg-rr55.6%
Simplified99.7%
Taylor expanded in x around inf 98.9%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (/ -2.0 (* (+ x_m -1.0) (+ x_m 1.0))))
x_m = fabs(x);
double code(double x_m) {
return -2.0 / ((x_m + -1.0) * (x_m + 1.0));
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = (-2.0d0) / ((x_m + (-1.0d0)) * (x_m + 1.0d0))
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return -2.0 / ((x_m + -1.0) * (x_m + 1.0));
}
x_m = math.fabs(x) def code(x_m): return -2.0 / ((x_m + -1.0) * (x_m + 1.0))
x_m = abs(x) function code(x_m) return Float64(-2.0 / Float64(Float64(x_m + -1.0) * Float64(x_m + 1.0))) end
x_m = abs(x); function tmp = code(x_m) tmp = -2.0 / ((x_m + -1.0) * (x_m + 1.0)); end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := N[(-2.0 / N[(N[(x$95$m + -1.0), $MachinePrecision] * N[(x$95$m + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
\frac{-2}{\left(x\_m + -1\right) \cdot \left(x\_m + 1\right)}
\end{array}
Initial program 77.1%
sub-neg77.1%
+-commutative77.1%
distribute-neg-frac277.1%
neg-sub077.1%
associate-+l-77.1%
neg-sub077.1%
remove-double-neg77.1%
distribute-neg-in77.1%
sub-neg77.1%
distribute-neg-frac277.1%
sub-neg77.1%
+-commutative77.1%
unsub-neg77.1%
sub-neg77.1%
+-commutative77.1%
unsub-neg77.1%
metadata-eval77.1%
Simplified77.1%
sub-neg77.1%
distribute-neg-frac77.1%
metadata-eval77.1%
Applied egg-rr77.1%
Simplified99.9%
Final simplification99.9%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (if (<= x_m 1.0) 2.0 (/ -2.0 x_m)))
x_m = fabs(x);
double code(double x_m) {
double tmp;
if (x_m <= 1.0) {
tmp = 2.0;
} else {
tmp = -2.0 / x_m;
}
return tmp;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
real(8) :: tmp
if (x_m <= 1.0d0) then
tmp = 2.0d0
else
tmp = (-2.0d0) / x_m
end if
code = tmp
end function
x_m = Math.abs(x);
public static double code(double x_m) {
double tmp;
if (x_m <= 1.0) {
tmp = 2.0;
} else {
tmp = -2.0 / x_m;
}
return tmp;
}
x_m = math.fabs(x) def code(x_m): tmp = 0 if x_m <= 1.0: tmp = 2.0 else: tmp = -2.0 / x_m return tmp
x_m = abs(x) function code(x_m) tmp = 0.0 if (x_m <= 1.0) tmp = 2.0; else tmp = Float64(-2.0 / x_m); end return tmp end
x_m = abs(x); function tmp_2 = code(x_m) tmp = 0.0; if (x_m <= 1.0) tmp = 2.0; else tmp = -2.0 / x_m; end tmp_2 = tmp; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := If[LessEqual[x$95$m, 1.0], 2.0, N[(-2.0 / x$95$m), $MachinePrecision]]
\begin{array}{l}
x_m = \left|x\right|
\\
\begin{array}{l}
\mathbf{if}\;x\_m \leq 1:\\
\;\;\;\;2\\
\mathbf{else}:\\
\;\;\;\;\frac{-2}{x\_m}\\
\end{array}
\end{array}
if x < 1Initial program 82.8%
sub-neg82.8%
+-commutative82.8%
distribute-neg-frac282.8%
neg-sub082.8%
associate-+l-82.8%
neg-sub082.8%
remove-double-neg82.8%
distribute-neg-in82.8%
sub-neg82.8%
distribute-neg-frac282.8%
sub-neg82.8%
+-commutative82.8%
unsub-neg82.8%
sub-neg82.8%
+-commutative82.8%
unsub-neg82.8%
metadata-eval82.8%
Simplified82.8%
Taylor expanded in x around 0 69.3%
if 1 < x Initial program 55.6%
sub-neg55.6%
+-commutative55.6%
distribute-neg-frac255.6%
neg-sub055.6%
associate-+l-55.6%
neg-sub055.6%
remove-double-neg55.6%
distribute-neg-in55.6%
sub-neg55.6%
distribute-neg-frac255.6%
sub-neg55.6%
+-commutative55.6%
unsub-neg55.6%
sub-neg55.6%
+-commutative55.6%
unsub-neg55.6%
metadata-eval55.6%
Simplified55.6%
frac-sub56.2%
*-rgt-identity56.2%
metadata-eval56.2%
div-inv56.2%
associate-/r*56.3%
metadata-eval56.3%
div-inv56.3%
*-un-lft-identity56.3%
associate--l-62.4%
div-inv62.4%
metadata-eval62.4%
*-rgt-identity62.4%
div-inv62.4%
metadata-eval62.4%
*-rgt-identity62.4%
Applied egg-rr62.4%
Taylor expanded in x around inf 99.0%
Taylor expanded in x around 0 6.7%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 (/ -2.0 (- -1.0 x_m)))
x_m = fabs(x);
double code(double x_m) {
return -2.0 / (-1.0 - x_m);
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = (-2.0d0) / ((-1.0d0) - x_m)
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return -2.0 / (-1.0 - x_m);
}
x_m = math.fabs(x) def code(x_m): return -2.0 / (-1.0 - x_m)
x_m = abs(x) function code(x_m) return Float64(-2.0 / Float64(-1.0 - x_m)) end
x_m = abs(x); function tmp = code(x_m) tmp = -2.0 / (-1.0 - x_m); end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := N[(-2.0 / N[(-1.0 - x$95$m), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
x_m = \left|x\right|
\\
\frac{-2}{-1 - x\_m}
\end{array}
Initial program 77.1%
sub-neg77.1%
+-commutative77.1%
distribute-neg-frac277.1%
neg-sub077.1%
associate-+l-77.1%
neg-sub077.1%
remove-double-neg77.1%
distribute-neg-in77.1%
sub-neg77.1%
distribute-neg-frac277.1%
sub-neg77.1%
+-commutative77.1%
unsub-neg77.1%
sub-neg77.1%
+-commutative77.1%
unsub-neg77.1%
metadata-eval77.1%
Simplified77.1%
frac-sub77.2%
*-rgt-identity77.2%
metadata-eval77.2%
div-inv77.2%
associate-/r*77.2%
metadata-eval77.2%
div-inv77.2%
*-un-lft-identity77.2%
associate--l-80.3%
div-inv80.3%
metadata-eval80.3%
*-rgt-identity80.3%
div-inv80.3%
metadata-eval80.3%
*-rgt-identity80.3%
Applied egg-rr80.3%
Taylor expanded in x around 0 55.9%
x_m = (fabs.f64 x) (FPCore (x_m) :precision binary64 2.0)
x_m = fabs(x);
double code(double x_m) {
return 2.0;
}
x_m = abs(x)
real(8) function code(x_m)
real(8), intent (in) :: x_m
code = 2.0d0
end function
x_m = Math.abs(x);
public static double code(double x_m) {
return 2.0;
}
x_m = math.fabs(x) def code(x_m): return 2.0
x_m = abs(x) function code(x_m) return 2.0 end
x_m = abs(x); function tmp = code(x_m) tmp = 2.0; end
x_m = N[Abs[x], $MachinePrecision] code[x$95$m_] := 2.0
\begin{array}{l}
x_m = \left|x\right|
\\
2
\end{array}
Initial program 77.1%
sub-neg77.1%
+-commutative77.1%
distribute-neg-frac277.1%
neg-sub077.1%
associate-+l-77.1%
neg-sub077.1%
remove-double-neg77.1%
distribute-neg-in77.1%
sub-neg77.1%
distribute-neg-frac277.1%
sub-neg77.1%
+-commutative77.1%
unsub-neg77.1%
sub-neg77.1%
+-commutative77.1%
unsub-neg77.1%
metadata-eval77.1%
Simplified77.1%
Taylor expanded in x around 0 55.2%
herbie shell --seed 2024157
(FPCore (x)
:name "Asymptote A"
:precision binary64
(- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))