
(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 11 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 (+ (pow x -3.0) (pow x -5.0))))
double code(double x) {
return 2.0 * (pow(x, -3.0) + pow(x, -5.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 * ((x ** (-3.0d0)) + (x ** (-5.0d0)))
end function
public static double code(double x) {
return 2.0 * (Math.pow(x, -3.0) + Math.pow(x, -5.0));
}
def code(x): return 2.0 * (math.pow(x, -3.0) + math.pow(x, -5.0))
function code(x) return Float64(2.0 * Float64((x ^ -3.0) + (x ^ -5.0))) end
function tmp = code(x) tmp = 2.0 * ((x ^ -3.0) + (x ^ -5.0)); end
code[x_] := N[(2.0 * N[(N[Power[x, -3.0], $MachinePrecision] + N[Power[x, -5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
2 \cdot \left({x}^{-3} + {x}^{-5}\right)
\end{array}
Initial program 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
Taylor expanded in x around inf 98.1%
associate-*r/98.1%
metadata-eval98.1%
associate-*r/98.1%
metadata-eval98.1%
Simplified98.1%
*-un-lft-identity98.1%
+-commutative98.1%
div-inv98.1%
fma-define98.1%
pow-flip98.1%
metadata-eval98.1%
div-inv98.1%
pow-flip99.4%
metadata-eval99.4%
Applied egg-rr99.4%
*-lft-identity99.4%
fma-undefine99.4%
+-commutative99.4%
distribute-lft-out99.4%
Simplified99.4%
Final simplification99.4%
(FPCore (x) :precision binary64 (/ 2.0 (pow x 3.0)))
double code(double x) {
return 2.0 / pow(x, 3.0);
}
real(8) function code(x)
real(8), intent (in) :: x
code = 2.0d0 / (x ** 3.0d0)
end function
public static double code(double x) {
return 2.0 / Math.pow(x, 3.0);
}
def code(x): return 2.0 / math.pow(x, 3.0)
function code(x) return Float64(2.0 / (x ^ 3.0)) end
function tmp = code(x) tmp = 2.0 / (x ^ 3.0); end
code[x_] := N[(2.0 / N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{2}{{x}^{3}}
\end{array}
Initial program 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
Taylor expanded in x around inf 97.5%
Final simplification97.5%
(FPCore (x) :precision binary64 (- (/ -2.0 x) (/ (/ (- (+ x -1.0) (- -1.0 x)) (- -1.0 x)) (+ x -1.0))))
double code(double x) {
return (-2.0 / x) - ((((x + -1.0) - (-1.0 - x)) / (-1.0 - x)) / (x + -1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((-2.0d0) / x) - ((((x + (-1.0d0)) - ((-1.0d0) - x)) / ((-1.0d0) - x)) / (x + (-1.0d0)))
end function
public static double code(double x) {
return (-2.0 / x) - ((((x + -1.0) - (-1.0 - x)) / (-1.0 - x)) / (x + -1.0));
}
def code(x): return (-2.0 / x) - ((((x + -1.0) - (-1.0 - x)) / (-1.0 - x)) / (x + -1.0))
function code(x) return Float64(Float64(-2.0 / x) - Float64(Float64(Float64(Float64(x + -1.0) - Float64(-1.0 - x)) / Float64(-1.0 - x)) / Float64(x + -1.0))) end
function tmp = code(x) tmp = (-2.0 / x) - ((((x + -1.0) - (-1.0 - x)) / (-1.0 - x)) / (x + -1.0)); end
code[x_] := N[(N[(-2.0 / x), $MachinePrecision] - N[(N[(N[(N[(x + -1.0), $MachinePrecision] - N[(-1.0 - x), $MachinePrecision]), $MachinePrecision] / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-2}{x} - \frac{\frac{\left(x + -1\right) - \left(-1 - x\right)}{-1 - x}}{x + -1}
\end{array}
Initial program 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
+-commutative67.5%
associate-+l-67.5%
Applied egg-rr67.5%
frac-sub19.3%
*-un-lft-identity19.3%
Applied egg-rr19.3%
*-rgt-identity19.3%
div-sub19.3%
/-rgt-identity19.3%
/-rgt-identity19.3%
*-rgt-identity19.3%
/-rgt-identity19.3%
div-sub19.3%
associate-/r*67.6%
/-rgt-identity67.6%
*-lft-identity67.6%
Simplified67.6%
Final simplification67.6%
(FPCore (x) :precision binary64 (+ (/ 1.0 (+ x -1.0)) (- (/ 1.0 (+ x 1.0)) (/ 2.0 x))))
double code(double x) {
return (1.0 / (x + -1.0)) + ((1.0 / (x + 1.0)) - (2.0 / x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (1.0d0 / (x + (-1.0d0))) + ((1.0d0 / (x + 1.0d0)) - (2.0d0 / x))
end function
public static double code(double x) {
return (1.0 / (x + -1.0)) + ((1.0 / (x + 1.0)) - (2.0 / x));
}
def code(x): return (1.0 / (x + -1.0)) + ((1.0 / (x + 1.0)) - (2.0 / x))
function code(x) return Float64(Float64(1.0 / Float64(x + -1.0)) + Float64(Float64(1.0 / Float64(x + 1.0)) - Float64(2.0 / x))) end
function tmp = code(x) tmp = (1.0 / (x + -1.0)) + ((1.0 / (x + 1.0)) - (2.0 / x)); end
code[x_] := N[(N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] + N[(N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(2.0 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x + -1} + \left(\frac{1}{x + 1} - \frac{2}{x}\right)
\end{array}
Initial program 67.5%
Final simplification67.5%
(FPCore (x) :precision binary64 (+ (/ -2.0 x) (+ (/ 1.0 (+ x -1.0)) (/ -1.0 (- -1.0 x)))))
double code(double x) {
return (-2.0 / x) + ((1.0 / (x + -1.0)) + (-1.0 / (-1.0 - x)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((-2.0d0) / x) + ((1.0d0 / (x + (-1.0d0))) + ((-1.0d0) / ((-1.0d0) - x)))
end function
public static double code(double x) {
return (-2.0 / x) + ((1.0 / (x + -1.0)) + (-1.0 / (-1.0 - x)));
}
def code(x): return (-2.0 / x) + ((1.0 / (x + -1.0)) + (-1.0 / (-1.0 - x)))
function code(x) return Float64(Float64(-2.0 / x) + Float64(Float64(1.0 / Float64(x + -1.0)) + Float64(-1.0 / Float64(-1.0 - x)))) end
function tmp = code(x) tmp = (-2.0 / x) + ((1.0 / (x + -1.0)) + (-1.0 / (-1.0 - x))); end
code[x_] := N[(N[(-2.0 / x), $MachinePrecision] + N[(N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] + N[(-1.0 / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-2}{x} + \left(\frac{1}{x + -1} + \frac{-1}{-1 - x}\right)
\end{array}
Initial program 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
+-commutative67.5%
associate-+l-67.5%
Applied egg-rr67.5%
Final simplification67.5%
(FPCore (x) :precision binary64 (/ (- x (+ x -1.0)) (* x (+ x -1.0))))
double code(double x) {
return (x - (x + -1.0)) / (x * (x + -1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (x - (x + (-1.0d0))) / (x * (x + (-1.0d0)))
end function
public static double code(double x) {
return (x - (x + -1.0)) / (x * (x + -1.0));
}
def code(x): return (x - (x + -1.0)) / (x * (x + -1.0))
function code(x) return Float64(Float64(x - Float64(x + -1.0)) / Float64(x * Float64(x + -1.0))) end
function tmp = code(x) tmp = (x - (x + -1.0)) / (x * (x + -1.0)); end
code[x_] := N[(N[(x - N[(x + -1.0), $MachinePrecision]), $MachinePrecision] / N[(x * N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{x - \left(x + -1\right)}{x \cdot \left(x + -1\right)}
\end{array}
Initial program 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
Taylor expanded in x around inf 66.0%
frac-add66.0%
*-un-lft-identity66.0%
Applied egg-rr66.0%
*-commutative66.0%
neg-mul-166.0%
unsub-neg66.0%
*-commutative66.0%
Simplified66.0%
Final simplification66.0%
(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 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
Taylor expanded in x around inf 66.0%
Final simplification66.0%
(FPCore (x) :precision binary64 (/ 1.0 (* x (+ x -1.0))))
double code(double x) {
return 1.0 / (x * (x + -1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = 1.0d0 / (x * (x + (-1.0d0)))
end function
public static double code(double x) {
return 1.0 / (x * (x + -1.0));
}
def code(x): return 1.0 / (x * (x + -1.0))
function code(x) return Float64(1.0 / Float64(x * Float64(x + -1.0))) end
function tmp = code(x) tmp = 1.0 / (x * (x + -1.0)); end
code[x_] := N[(1.0 / N[(x * N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{1}{x \cdot \left(x + -1\right)}
\end{array}
Initial program 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
Taylor expanded in x around inf 66.0%
frac-add66.0%
*-un-lft-identity66.0%
Applied egg-rr66.0%
*-commutative66.0%
neg-mul-166.0%
unsub-neg66.0%
*-commutative66.0%
Simplified66.0%
Taylor expanded in x around 0 51.0%
Final simplification51.0%
(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 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
Taylor expanded in x around 0 5.0%
Final simplification5.0%
(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 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
Taylor expanded in x around inf 66.0%
Taylor expanded in x around 0 5.0%
Final simplification5.0%
(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 67.5%
+-commutative67.5%
associate-+r-67.5%
sub-neg67.5%
remove-double-neg67.5%
neg-sub067.5%
associate-+l-67.5%
neg-sub067.5%
distribute-neg-frac267.5%
distribute-frac-neg267.5%
associate-+r+67.5%
+-commutative67.5%
remove-double-neg67.5%
distribute-neg-frac267.5%
sub0-neg67.5%
associate-+l-67.5%
neg-sub067.5%
Simplified67.5%
Taylor expanded in x around 0 3.4%
Taylor expanded in x around inf 3.4%
Final simplification3.4%
(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 2024050
(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))))