
(FPCore (x) :precision binary64 (+ (/ 1.0 (- x 1.0)) (/ x (+ x 1.0))))
double code(double x) {
return (1.0 / (x - 1.0)) + (x / (x + 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x - 1.0d0)) + (x / (x + 1.0d0))
end function
public static double code(double x) {
return (1.0 / (x - 1.0)) + (x / (x + 1.0));
}
def code(x): return (1.0 / (x - 1.0)) + (x / (x + 1.0))
function code(x) return Float64(Float64(1.0 / Float64(x - 1.0)) + Float64(x / Float64(x + 1.0))) end
function tmp = code(x) tmp = (1.0 / (x - 1.0)) + (x / (x + 1.0)); end
code[x_] := N[(N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision] + N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x - 1} + \frac{x}{x + 1}
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 5 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x) :precision binary64 (+ (/ 1.0 (- x 1.0)) (/ x (+ x 1.0))))
double code(double x) {
return (1.0 / (x - 1.0)) + (x / (x + 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x - 1.0d0)) + (x / (x + 1.0d0))
end function
public static double code(double x) {
return (1.0 / (x - 1.0)) + (x / (x + 1.0));
}
def code(x): return (1.0 / (x - 1.0)) + (x / (x + 1.0))
function code(x) return Float64(Float64(1.0 / Float64(x - 1.0)) + Float64(x / Float64(x + 1.0))) end
function tmp = code(x) tmp = (1.0 / (x - 1.0)) + (x / (x + 1.0)); end
code[x_] := N[(N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision] + N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x - 1} + \frac{x}{x + 1}
\end{array}
(FPCore (x) :precision binary64 (+ (/ 1.0 (+ x -1.0)) (/ x (+ 1.0 x))))
double code(double x) {
return (1.0 / (x + -1.0)) + (x / (1.0 + x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x + (-1.0d0))) + (x / (1.0d0 + x))
end function
public static double code(double x) {
return (1.0 / (x + -1.0)) + (x / (1.0 + x));
}
def code(x): return (1.0 / (x + -1.0)) + (x / (1.0 + x))
function code(x) return Float64(Float64(1.0 / Float64(x + -1.0)) + Float64(x / Float64(1.0 + x))) end
function tmp = code(x) tmp = (1.0 / (x + -1.0)) + (x / (1.0 + x)); end
code[x_] := N[(N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] + N[(x / N[(1.0 + x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x + -1} + \frac{x}{1 + x}
\end{array}
Initial program 100.0%
Final simplification100.0%
(FPCore (x) :precision binary64 (let* ((t_0 (+ 1.0 (/ 2.0 (* x x))))) (if (<= x -1.0) t_0 (if (<= x 1.0) (+ -1.0 (* (* x x) -2.0)) t_0))))
double code(double x) {
double t_0 = 1.0 + (2.0 / (x * x));
double tmp;
if (x <= -1.0) {
tmp = t_0;
} else if (x <= 1.0) {
tmp = -1.0 + ((x * x) * -2.0);
} else {
tmp = t_0;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: t_0
real(8) :: tmp
t_0 = 1.0d0 + (2.0d0 / (x * x))
if (x <= (-1.0d0)) then
tmp = t_0
else if (x <= 1.0d0) then
tmp = (-1.0d0) + ((x * x) * (-2.0d0))
else
tmp = t_0
end if
code = tmp
end function
public static double code(double x) {
double t_0 = 1.0 + (2.0 / (x * x));
double tmp;
if (x <= -1.0) {
tmp = t_0;
} else if (x <= 1.0) {
tmp = -1.0 + ((x * x) * -2.0);
} else {
tmp = t_0;
}
return tmp;
}
def code(x): t_0 = 1.0 + (2.0 / (x * x)) tmp = 0 if x <= -1.0: tmp = t_0 elif x <= 1.0: tmp = -1.0 + ((x * x) * -2.0) else: tmp = t_0 return tmp
function code(x) t_0 = Float64(1.0 + Float64(2.0 / Float64(x * x))) tmp = 0.0 if (x <= -1.0) tmp = t_0; elseif (x <= 1.0) tmp = Float64(-1.0 + Float64(Float64(x * x) * -2.0)); else tmp = t_0; end return tmp end
function tmp_2 = code(x) t_0 = 1.0 + (2.0 / (x * x)); tmp = 0.0; if (x <= -1.0) tmp = t_0; elseif (x <= 1.0) tmp = -1.0 + ((x * x) * -2.0); else tmp = t_0; end tmp_2 = tmp; end
code[x_] := Block[{t$95$0 = N[(1.0 + N[(2.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, -1.0], t$95$0, If[LessEqual[x, 1.0], N[(-1.0 + N[(N[(x * x), $MachinePrecision] * -2.0), $MachinePrecision]), $MachinePrecision], t$95$0]]]
\begin{array}{l}
\\
\begin{array}{l}
t_0 := 1 + \frac{2}{x \cdot x}\\
\mathbf{if}\;x \leq -1:\\
\;\;\;\;t\_0\\
\mathbf{elif}\;x \leq 1:\\
\;\;\;\;-1 + \left(x \cdot x\right) \cdot -2\\
\mathbf{else}:\\
\;\;\;\;t\_0\\
\end{array}
\end{array}
if x < -1 or 1 < x Initial program 100.0%
Taylor expanded in x around inf
+-lowering-+.f64N/A
associate-*r/N/A
metadata-evalN/A
/-lowering-/.f64N/A
unpow2N/A
*-lowering-*.f6499.3%
Simplified99.3%
if -1 < x < 1Initial program 100.0%
Taylor expanded in x around 0
sub-negN/A
metadata-evalN/A
+-commutativeN/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f6499.6%
Simplified99.6%
Final simplification99.4%
(FPCore (x) :precision binary64 (if (<= x -1.0) 1.0 (if (<= x 1.0) (+ -1.0 (* (* x x) -2.0)) 1.0)))
double code(double x) {
double tmp;
if (x <= -1.0) {
tmp = 1.0;
} else if (x <= 1.0) {
tmp = -1.0 + ((x * x) * -2.0);
} else {
tmp = 1.0;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= (-1.0d0)) then
tmp = 1.0d0
else if (x <= 1.0d0) then
tmp = (-1.0d0) + ((x * x) * (-2.0d0))
else
tmp = 1.0d0
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= -1.0) {
tmp = 1.0;
} else if (x <= 1.0) {
tmp = -1.0 + ((x * x) * -2.0);
} else {
tmp = 1.0;
}
return tmp;
}
def code(x): tmp = 0 if x <= -1.0: tmp = 1.0 elif x <= 1.0: tmp = -1.0 + ((x * x) * -2.0) else: tmp = 1.0 return tmp
function code(x) tmp = 0.0 if (x <= -1.0) tmp = 1.0; elseif (x <= 1.0) tmp = Float64(-1.0 + Float64(Float64(x * x) * -2.0)); else tmp = 1.0; end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= -1.0) tmp = 1.0; elseif (x <= 1.0) tmp = -1.0 + ((x * x) * -2.0); else tmp = 1.0; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, -1.0], 1.0, If[LessEqual[x, 1.0], N[(-1.0 + N[(N[(x * x), $MachinePrecision] * -2.0), $MachinePrecision]), $MachinePrecision], 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 1:\\
\;\;\;\;-1 + \left(x \cdot x\right) \cdot -2\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -1 or 1 < x Initial program 100.0%
Taylor expanded in x around inf
Simplified98.6%
if -1 < x < 1Initial program 100.0%
Taylor expanded in x around 0
sub-negN/A
metadata-evalN/A
+-commutativeN/A
+-lowering-+.f64N/A
*-lowering-*.f64N/A
unpow2N/A
*-lowering-*.f6499.6%
Simplified99.6%
Final simplification99.1%
(FPCore (x) :precision binary64 (if (<= x -1.0) 1.0 (if (<= x 1.0) -1.0 1.0)))
double code(double x) {
double tmp;
if (x <= -1.0) {
tmp = 1.0;
} else if (x <= 1.0) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
real(8) function code(x)
real(8), intent (in) :: x
real(8) :: tmp
if (x <= (-1.0d0)) then
tmp = 1.0d0
else if (x <= 1.0d0) then
tmp = -1.0d0
else
tmp = 1.0d0
end if
code = tmp
end function
public static double code(double x) {
double tmp;
if (x <= -1.0) {
tmp = 1.0;
} else if (x <= 1.0) {
tmp = -1.0;
} else {
tmp = 1.0;
}
return tmp;
}
def code(x): tmp = 0 if x <= -1.0: tmp = 1.0 elif x <= 1.0: tmp = -1.0 else: tmp = 1.0 return tmp
function code(x) tmp = 0.0 if (x <= -1.0) tmp = 1.0; elseif (x <= 1.0) tmp = -1.0; else tmp = 1.0; end return tmp end
function tmp_2 = code(x) tmp = 0.0; if (x <= -1.0) tmp = 1.0; elseif (x <= 1.0) tmp = -1.0; else tmp = 1.0; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, -1.0], 1.0, If[LessEqual[x, 1.0], -1.0, 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 1:\\
\;\;\;\;-1\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -1 or 1 < x Initial program 100.0%
Taylor expanded in x around inf
Simplified98.6%
if -1 < x < 1Initial program 100.0%
Taylor expanded in x around 0
Simplified99.2%
(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 100.0%
Taylor expanded in x around 0
Simplified51.5%
herbie shell --seed 2024161
(FPCore (x)
:name "Asymptote B"
:precision binary64
(+ (/ 1.0 (- x 1.0)) (/ x (+ x 1.0))))