
(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 12 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 (/ 2.0 (* x x))) (pow x -3.0)))
double code(double x) {
return (2.0 + (2.0 / (x * x))) * pow(x, -3.0);
}
real(8) function code(x)
real(8), intent (in) :: x
code = (2.0d0 + (2.0d0 / (x * x))) * (x ** (-3.0d0))
end function
public static double code(double x) {
return (2.0 + (2.0 / (x * x))) * Math.pow(x, -3.0);
}
def code(x): return (2.0 + (2.0 / (x * x))) * math.pow(x, -3.0)
function code(x) return Float64(Float64(2.0 + Float64(2.0 / Float64(x * x))) * (x ^ -3.0)) end
function tmp = code(x) tmp = (2.0 + (2.0 / (x * x))) * (x ^ -3.0); end
code[x_] := N[(N[(2.0 + N[(2.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Power[x, -3.0], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(2 + \frac{2}{x \cdot x}\right) \cdot {x}^{-3}
\end{array}
Initial program 67.9%
Simplified67.9%
Taylor expanded in x around inf 99.2%
associate-*r/99.2%
metadata-eval99.2%
Simplified99.2%
div-inv99.1%
+-commutative99.1%
div-inv99.1%
fma-define99.1%
pow-flip99.1%
metadata-eval99.1%
pow-flip99.4%
metadata-eval99.4%
Applied egg-rr99.4%
metadata-eval99.4%
pow-flip99.4%
pow299.4%
fma-define99.4%
div-inv99.4%
pow299.4%
Applied egg-rr99.4%
unpow299.4%
Applied egg-rr99.4%
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}
\\
2 \cdot {x}^{-3}
\end{array}
Initial program 67.9%
Simplified67.9%
Taylor expanded in x around inf 99.2%
associate-*r/99.2%
metadata-eval99.2%
Simplified99.2%
div-inv99.1%
+-commutative99.1%
div-inv99.1%
fma-define99.1%
pow-flip99.1%
metadata-eval99.1%
pow-flip99.4%
metadata-eval99.4%
Applied egg-rr99.4%
Taylor expanded in x around inf 98.8%
(FPCore (x) :precision binary64 (+ (/ (/ 1.0 (- 1.0 (/ -1.0 x))) x) (+ (/ -2.0 x) (/ 1.0 (+ x -1.0)))))
double code(double x) {
return ((1.0 / (1.0 - (-1.0 / x))) / x) + ((-2.0 / x) + (1.0 / (x + -1.0)));
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((1.0d0 / (1.0d0 - ((-1.0d0) / x))) / x) + (((-2.0d0) / x) + (1.0d0 / (x + (-1.0d0))))
end function
public static double code(double x) {
return ((1.0 / (1.0 - (-1.0 / x))) / x) + ((-2.0 / x) + (1.0 / (x + -1.0)));
}
def code(x): return ((1.0 / (1.0 - (-1.0 / x))) / x) + ((-2.0 / x) + (1.0 / (x + -1.0)))
function code(x) return Float64(Float64(Float64(1.0 / Float64(1.0 - Float64(-1.0 / x))) / x) + Float64(Float64(-2.0 / x) + Float64(1.0 / Float64(x + -1.0)))) end
function tmp = code(x) tmp = ((1.0 / (1.0 - (-1.0 / x))) / x) + ((-2.0 / x) + (1.0 / (x + -1.0))); end
code[x_] := N[(N[(N[(1.0 / N[(1.0 - N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] + N[(N[(-2.0 / x), $MachinePrecision] + N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\frac{1}{1 - \frac{-1}{x}}}{x} + \left(\frac{-2}{x} + \frac{1}{x + -1}\right)
\end{array}
Initial program 67.9%
Simplified67.9%
Taylor expanded in x around inf 68.0%
inv-pow68.0%
unpow-prod-down68.1%
inv-pow68.0%
Applied egg-rr68.0%
associate-*l/68.1%
*-lft-identity68.1%
unpow-168.1%
Simplified68.1%
Final simplification68.1%
(FPCore (x) :precision binary64 (+ (+ (/ -2.0 x) (/ 1.0 (+ x -1.0))) (/ 1.0 (* x (- 1.0 (/ -1.0 x))))))
double code(double x) {
return ((-2.0 / x) + (1.0 / (x + -1.0))) + (1.0 / (x * (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 / (x * (1.0d0 - ((-1.0d0) / x))))
end function
public static double code(double x) {
return ((-2.0 / x) + (1.0 / (x + -1.0))) + (1.0 / (x * (1.0 - (-1.0 / x))));
}
def code(x): return ((-2.0 / x) + (1.0 / (x + -1.0))) + (1.0 / (x * (1.0 - (-1.0 / x))))
function code(x) return Float64(Float64(Float64(-2.0 / x) + Float64(1.0 / Float64(x + -1.0))) + Float64(1.0 / Float64(x * Float64(1.0 - Float64(-1.0 / x))))) end
function tmp = code(x) tmp = ((-2.0 / x) + (1.0 / (x + -1.0))) + (1.0 / (x * (1.0 - (-1.0 / x)))); end
code[x_] := N[(N[(N[(-2.0 / x), $MachinePrecision] + N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x * N[(1.0 - N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{-2}{x} + \frac{1}{x + -1}\right) + \frac{1}{x \cdot \left(1 - \frac{-1}{x}\right)}
\end{array}
Initial program 67.9%
Simplified67.9%
Taylor expanded in x around inf 68.0%
Final simplification68.0%
(FPCore (x) :precision binary64 (+ (+ (/ -2.0 x) (/ 1.0 (+ x -1.0))) (/ 1.0 (+ x 1.0))))
double code(double x) {
return ((-2.0 / x) + (1.0 / (x + -1.0))) + (1.0 / (x + 1.0));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (((-2.0d0) / x) + (1.0d0 / (x + (-1.0d0)))) + (1.0d0 / (x + 1.0d0))
end function
public static double code(double x) {
return ((-2.0 / x) + (1.0 / (x + -1.0))) + (1.0 / (x + 1.0));
}
def code(x): return ((-2.0 / x) + (1.0 / (x + -1.0))) + (1.0 / (x + 1.0))
function code(x) return Float64(Float64(Float64(-2.0 / x) + Float64(1.0 / Float64(x + -1.0))) + Float64(1.0 / Float64(x + 1.0))) end
function tmp = code(x) tmp = ((-2.0 / x) + (1.0 / (x + -1.0))) + (1.0 / (x + 1.0)); end
code[x_] := N[(N[(N[(-2.0 / x), $MachinePrecision] + N[(1.0 / N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(1.0 / N[(x + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{-2}{x} + \frac{1}{x + -1}\right) + \frac{1}{x + 1}
\end{array}
Initial program 67.9%
Simplified67.9%
Final simplification67.9%
(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 67.9%
Final simplification67.9%
(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 67.9%
Simplified67.9%
Taylor expanded in x around inf 66.5%
*-un-lft-identity66.5%
Applied egg-rr66.5%
*-lft-identity66.5%
associate-+r+66.5%
metadata-eval66.5%
associate-*r/66.5%
distribute-rgt1-in66.5%
metadata-eval66.5%
neg-mul-166.5%
distribute-neg-frac66.5%
metadata-eval66.5%
Simplified66.5%
Final simplification66.5%
(FPCore (x) :precision binary64 (+ -1.0 (- 1.0 (/ -1.0 x))))
double code(double x) {
return -1.0 + (1.0 - (-1.0 / x));
}
real(8) function code(x)
real(8), intent (in) :: x
code = (-1.0d0) + (1.0d0 - ((-1.0d0) / x))
end function
public static double code(double x) {
return -1.0 + (1.0 - (-1.0 / x));
}
def code(x): return -1.0 + (1.0 - (-1.0 / x))
function code(x) return Float64(-1.0 + Float64(1.0 - Float64(-1.0 / x))) end
function tmp = code(x) tmp = -1.0 + (1.0 - (-1.0 / x)); end
code[x_] := N[(-1.0 + N[(1.0 - N[(-1.0 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
-1 + \left(1 - \frac{-1}{x}\right)
\end{array}
Initial program 67.9%
Simplified67.9%
Taylor expanded in x around inf 66.5%
Taylor expanded in x around 0 4.9%
div-inv4.9%
mul-1-neg4.9%
add-sqr-sqrt2.3%
sqrt-prod48.6%
frac-times50.8%
metadata-eval50.8%
metadata-eval50.8%
frac-times48.6%
sqrt-unprod3.4%
add-sqr-sqrt6.3%
Applied egg-rr6.3%
add-sqr-sqrt3.4%
sqrt-unprod48.6%
frac-times50.8%
metadata-eval50.8%
metadata-eval50.8%
frac-times48.6%
sqrt-prod2.3%
expm1-log1p-u2.3%
add-sqr-sqrt4.9%
expm1-undefine66.2%
Applied egg-rr66.8%
associate--l+66.8%
Simplified66.8%
Final simplification66.8%
(FPCore (x) :precision binary64 (+ (/ -1.0 x) (/ 1.0 x)))
double code(double x) {
return (-1.0 / x) + (1.0 / x);
}
real(8) function code(x)
real(8), intent (in) :: x
code = ((-1.0d0) / x) + (1.0d0 / x)
end function
public static double code(double x) {
return (-1.0 / x) + (1.0 / x);
}
def code(x): return (-1.0 / x) + (1.0 / x)
function code(x) return Float64(Float64(-1.0 / x) + Float64(1.0 / x)) end
function tmp = code(x) tmp = (-1.0 / x) + (1.0 / x); end
code[x_] := N[(N[(-1.0 / x), $MachinePrecision] + N[(1.0 / x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{-1}{x} + \frac{1}{x}
\end{array}
Initial program 67.9%
Simplified67.9%
Taylor expanded in x around inf 66.5%
Taylor expanded in x around inf 66.3%
Final simplification66.3%
(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 67.9%
Simplified67.9%
Taylor expanded in x around inf 66.5%
Taylor expanded in x around 0 4.9%
div-inv4.9%
mul-1-neg4.9%
add-sqr-sqrt2.3%
sqrt-prod48.6%
frac-times50.8%
metadata-eval50.8%
metadata-eval50.8%
frac-times48.6%
sqrt-unprod3.4%
add-sqr-sqrt6.3%
Applied egg-rr6.3%
Taylor expanded in x around 0 6.3%
(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 67.9%
Simplified67.9%
Taylor expanded in x around inf 66.5%
Taylor expanded in x around 0 4.9%
(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 67.9%
Simplified67.9%
Taylor expanded in x around 0 4.9%
(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 2024145
(FPCore (x)
:name "3frac (problem 3.3.3)"
:precision binary64
:pre (> (fabs x) 1.0)
:alt
(! :herbie-platform default (/ 2 (* x (- (* x x) 1))))
(+ (- (/ 1.0 (+ x 1.0)) (/ 2.0 x)) (/ 1.0 (- x 1.0))))