
(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 4 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 (+ (/ x (+ 1.0 x)) (/ 1.0 (+ x -1.0))))
double code(double x) {
return (x / (1.0 + x)) + (1.0 / (x + -1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x / (1.0d0 + x)) + (1.0d0 / (x + (-1.0d0)))
end function
public static double code(double x) {
return (x / (1.0 + x)) + (1.0 / (x + -1.0));
}
def code(x): return (x / (1.0 + x)) + (1.0 / (x + -1.0))
function code(x) return Float64(Float64(x / Float64(1.0 + x)) + Float64(1.0 / Float64(x + -1.0))) end
function tmp = code(x) tmp = (x / (1.0 + x)) + (1.0 / (x + -1.0)); end
code[x_] := N[(N[(x / N[(1.0 + x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x}{1 + x} + \frac{1}{x + -1}
\end{array}
Initial program 100.0%
Final simplification100.0%
(FPCore (x) :precision binary64 (if (<= x -1.0) 1.0 (if (<= x 1.9) (+ x (/ 1.0 (+ x -1.0))) 1.0)))
double code(double x) {
double tmp;
if (x <= -1.0) {
tmp = 1.0;
} else if (x <= 1.9) {
tmp = x + (1.0 / (x + -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 <= 1.9d0) then
tmp = x + (1.0d0 / (x + (-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 <= 1.9) {
tmp = x + (1.0 / (x + -1.0));
} else {
tmp = 1.0;
}
return tmp;
}
def code(x): tmp = 0 if x <= -1.0: tmp = 1.0 elif x <= 1.9: tmp = x + (1.0 / (x + -1.0)) else: tmp = 1.0 return tmp
function code(x) tmp = 0.0 if (x <= -1.0) tmp = 1.0; elseif (x <= 1.9) tmp = Float64(x + Float64(1.0 / Float64(x + -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 <= 1.9) tmp = x + (1.0 / (x + -1.0)); else tmp = 1.0; end tmp_2 = tmp; end
code[x_] := If[LessEqual[x, -1.0], 1.0, If[LessEqual[x, 1.9], N[(x + N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 1.0]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;x \leq -1:\\
\;\;\;\;1\\
\mathbf{elif}\;x \leq 1.9:\\
\;\;\;\;x + \frac{1}{x + -1}\\
\mathbf{else}:\\
\;\;\;\;1\\
\end{array}
\end{array}
if x < -1 or 1.8999999999999999 < x Initial program 100.0%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in x around inf 99.0%
if -1 < x < 1.8999999999999999Initial program 100.0%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in x around 0 99.5%
(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%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in x around inf 99.0%
if -1 < x < 1Initial program 100.0%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in x around 0 99.5%
(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%
+-commutative100.0%
+-commutative100.0%
sub-neg100.0%
metadata-eval100.0%
Simplified100.0%
Taylor expanded in x around 0 50.5%
herbie shell --seed 2024086
(FPCore (x)
:name "Asymptote B"
:precision binary64
(+ (/ 1.0 (- x 1.0)) (/ x (+ x 1.0))))