
(FPCore (x) :precision binary64 (+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))
double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((1.0d0 / (x + 1.0d0)) - (2.0d0 / x)) + (1.0d0 / (x - 1.0d0))
end function
public static double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
def code(x): return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0))
function code(x) return Float64(Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(2.0 / x)) + Float64(1.0 / Float64(x - 1.0))) end
function tmp = code(x) tmp = ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0)); end
code[x_] := N[(N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(2.0 / x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \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)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))
double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((1.0d0 / (x + 1.0d0)) - (2.0d0 / x)) + (1.0d0 / (x - 1.0d0))
end function
public static double code(double x) {
return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0));
}
def code(x): return ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0))
function code(x) return Float64(Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(2.0 / x)) + Float64(1.0 / Float64(x - 1.0))) end
function tmp = code(x) tmp = ((1.0 / (x + 1.0)) - (2.0 / x)) + (1.0 / (x - 1.0)); end
code[x_] := N[(N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(2.0 / x), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1}
\end{array}
(FPCore (x) :precision binary64 (/ (/ -2.0 x) (* (- -1.0 x) (+ x -1.0))))
double code(double x) {
return (-2.0 / x) / ((-1.0 - x) * (x + -1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((-2.0d0) / x) / (((-1.0d0) - x) * (x + (-1.0d0)))
end function
public static double code(double x) {
return (-2.0 / x) / ((-1.0 - x) * (x + -1.0));
}
def code(x): return (-2.0 / x) / ((-1.0 - x) * (x + -1.0))
function code(x) return Float64(Float64(-2.0 / x) / Float64(Float64(-1.0 - x) * Float64(x + -1.0))) end
function tmp = code(x) tmp = (-2.0 / x) / ((-1.0 - x) * (x + -1.0)); end
code[x_] := N[(N[(-2.0 / x), $MachinePrecision] / N[(N[(-1.0 - x), $MachinePrecision] * N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{-2}{x}}{\left(-1 - x\right) \cdot \left(x + -1\right)}
\end{array}
Initial program 72.4%
+-commutative72.4%
associate-+r-72.4%
sub-neg72.4%
remove-double-neg72.4%
neg-sub072.4%
associate-+l-72.4%
neg-sub072.4%
distribute-neg-frac272.4%
distribute-frac-neg272.4%
associate-+r+72.4%
+-commutative72.4%
remove-double-neg72.4%
distribute-neg-frac272.4%
sub0-neg72.4%
associate-+l-72.4%
neg-sub072.4%
Simplified72.4%
+-commutative72.4%
associate-+l-72.4%
Applied egg-rr72.4%
frac-sub18.3%
frac-sub20.4%
*-un-lft-identity20.4%
*-rgt-identity20.4%
Applied egg-rr20.4%
Taylor expanded in x around 0 99.5%
div-inv99.5%
Applied egg-rr99.5%
associate-*r/99.5%
metadata-eval99.5%
associate-/r*99.8%
Simplified99.8%
Final simplification99.8%
(FPCore (x) :precision binary64 (/ -2.0 (* x (* (- -1.0 x) (+ x -1.0)))))
double code(double x) {
return -2.0 / (x * ((-1.0 - x) * (x + -1.0)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-2.0d0) / (x * (((-1.0d0) - x) * (x + (-1.0d0))))
end function
public static double code(double x) {
return -2.0 / (x * ((-1.0 - x) * (x + -1.0)));
}
def code(x): return -2.0 / (x * ((-1.0 - x) * (x + -1.0)))
function code(x) return Float64(-2.0 / Float64(x * Float64(Float64(-1.0 - x) * Float64(x + -1.0)))) end
function tmp = code(x) tmp = -2.0 / (x * ((-1.0 - x) * (x + -1.0))); end
code[x_] := N[(-2.0 / N[(x * N[(N[(-1.0 - x), $MachinePrecision] * N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-2}{x \cdot \left(\left(-1 - x\right) \cdot \left(x + -1\right)\right)}
\end{array}
Initial program 72.4%
+-commutative72.4%
associate-+r-72.4%
sub-neg72.4%
remove-double-neg72.4%
neg-sub072.4%
associate-+l-72.4%
neg-sub072.4%
distribute-neg-frac272.4%
distribute-frac-neg272.4%
associate-+r+72.4%
+-commutative72.4%
remove-double-neg72.4%
distribute-neg-frac272.4%
sub0-neg72.4%
associate-+l-72.4%
neg-sub072.4%
Simplified72.4%
+-commutative72.4%
associate-+l-72.4%
Applied egg-rr72.4%
frac-sub18.3%
frac-sub20.4%
*-un-lft-identity20.4%
*-rgt-identity20.4%
Applied egg-rr20.4%
Taylor expanded in x around 0 99.5%
Final simplification99.5%
(FPCore (x) :precision binary64 (+ (/ 1.0 (+ x -1.0)) (/ -1.0 x)))
double code(double x) {
return (1.0 / (x + -1.0)) + (-1.0 / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x + (-1.0d0))) + ((-1.0d0) / x)
end function
public static double code(double x) {
return (1.0 / (x + -1.0)) + (-1.0 / x);
}
def code(x): return (1.0 / (x + -1.0)) + (-1.0 / x)
function code(x) return Float64(Float64(1.0 / Float64(x + -1.0)) + Float64(-1.0 / x)) end
function tmp = code(x) tmp = (1.0 / (x + -1.0)) + (-1.0 / x); end
code[x_] := N[(N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x + -1} + \frac{-1}{x}
\end{array}
Initial program 72.4%
+-commutative72.4%
associate-+r-72.4%
sub-neg72.4%
remove-double-neg72.4%
neg-sub072.4%
associate-+l-72.4%
neg-sub072.4%
distribute-neg-frac272.4%
distribute-frac-neg272.4%
associate-+r+72.4%
+-commutative72.4%
remove-double-neg72.4%
distribute-neg-frac272.4%
sub0-neg72.4%
associate-+l-72.4%
neg-sub072.4%
Simplified72.4%
Taylor expanded in x around inf 70.2%
Final simplification70.2%
(FPCore (x) :precision binary64 (- (/ -2.0 x) (/ -2.0 x)))
double code(double x) {
return (-2.0 / x) - (-2.0 / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((-2.0d0) / x) - ((-2.0d0) / x)
end function
public static double code(double x) {
return (-2.0 / x) - (-2.0 / x);
}
def code(x): return (-2.0 / x) - (-2.0 / x)
function code(x) return Float64(Float64(-2.0 / x) - Float64(-2.0 / x)) end
function tmp = code(x) tmp = (-2.0 / x) - (-2.0 / x); end
code[x_] := N[(N[(-2.0 / x), $MachinePrecision] - N[(-2.0 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-2}{x} - \frac{-2}{x}
\end{array}
Initial program 72.4%
+-commutative72.4%
associate-+r-72.4%
sub-neg72.4%
remove-double-neg72.4%
neg-sub072.4%
associate-+l-72.4%
neg-sub072.4%
distribute-neg-frac272.4%
distribute-frac-neg272.4%
associate-+r+72.4%
+-commutative72.4%
remove-double-neg72.4%
distribute-neg-frac272.4%
sub0-neg72.4%
associate-+l-72.4%
neg-sub072.4%
Simplified72.4%
+-commutative72.4%
associate-+l-72.4%
Applied egg-rr72.4%
frac-sub18.3%
div-inv16.9%
*-un-lft-identity16.9%
*-rgt-identity16.9%
Applied egg-rr16.9%
associate-*r/18.3%
*-rgt-identity18.3%
associate--l+18.3%
sub-neg18.3%
associate--r+18.3%
metadata-eval18.3%
neg-sub018.3%
remove-double-neg18.3%
Simplified18.3%
Taylor expanded in x around inf 70.2%
Final simplification70.2%
(FPCore (x) :precision binary64 (/ -2.0 x))
double code(double x) {
return -2.0 / x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-2.0d0) / x
end function
public static double code(double x) {
return -2.0 / x;
}
def code(x): return -2.0 / x
function code(x) return Float64(-2.0 / x) end
function tmp = code(x) tmp = -2.0 / x; end
code[x_] := N[(-2.0 / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{-2}{x}
\end{array}
Initial program 72.4%
+-commutative72.4%
associate-+r-72.4%
sub-neg72.4%
remove-double-neg72.4%
neg-sub072.4%
associate-+l-72.4%
neg-sub072.4%
distribute-neg-frac272.4%
distribute-frac-neg272.4%
associate-+r+72.4%
+-commutative72.4%
remove-double-neg72.4%
distribute-neg-frac272.4%
sub0-neg72.4%
associate-+l-72.4%
neg-sub072.4%
Simplified72.4%
Taylor expanded in x around 0 5.3%
Final simplification5.3%
(FPCore (x) :precision binary64 (/ -1.0 x))
double code(double x) {
return -1.0 / x;
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-1.0d0) / x
end function
public static double code(double x) {
return -1.0 / x;
}
def code(x): return -1.0 / x
function code(x) return Float64(-1.0 / x) end
function tmp = code(x) tmp = -1.0 / x; end
code[x_] := N[(-1.0 / x), $MachinePrecision]
\begin{array}{l}
\\
\frac{-1}{x}
\end{array}
Initial program 72.4%
+-commutative72.4%
associate-+r-72.4%
sub-neg72.4%
remove-double-neg72.4%
neg-sub072.4%
associate-+l-72.4%
neg-sub072.4%
distribute-neg-frac272.4%
distribute-frac-neg272.4%
associate-+r+72.4%
+-commutative72.4%
remove-double-neg72.4%
distribute-neg-frac272.4%
sub0-neg72.4%
associate-+l-72.4%
neg-sub072.4%
Simplified72.4%
Taylor expanded in x around inf 70.2%
Taylor expanded in x around 0 5.3%
Final simplification5.3%
(FPCore (x) :precision binary64 (/ 2.0 (* x (- (* x x) 1.0))))
double code(double x) {
return 2.0 / (x * ((x * x) - 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / (x * ((x * x) - 1.0d0))
end function
public static double code(double x) {
return 2.0 / (x * ((x * x) - 1.0));
}
def code(x): return 2.0 / (x * ((x * x) - 1.0))
function code(x) return Float64(2.0 / Float64(x * Float64(Float64(x * x) - 1.0))) end
function tmp = code(x) tmp = 2.0 / (x * ((x * x) - 1.0)); end
code[x_] := N[(2.0 / N[(x * N[(N[(x * x), $MachinePrecision] - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{x \cdot \left(x \cdot x - 1\right)}
\end{array}
herbie shell --seed 2024055
(FPCore (x)
:name "3frac (problem 3.3.3)"
:precision binary64
:pre (> (fabs x) 1.0)
:alt
(/ 2.0 (* x (- (* x x) 1.0)))
(+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))