Asymptote C

Percentage Accurate: 54.5% → 99.6%
Time: 8.3s
Alternatives: 10
Speedup: 1.0×

Specification

?
\[\begin{array}{l} \\ \frac{x}{x + 1} - \frac{x + 1}{x - 1} \end{array} \]
(FPCore (x) :precision binary64 (- (/ x (+ x 1.0)) (/ (+ x 1.0) (- x 1.0))))
double code(double x) {
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x / (x + 1.0d0)) - ((x + 1.0d0) / (x - 1.0d0))
end function
public static double code(double x) {
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
def code(x):
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0))
function code(x)
	return Float64(Float64(x / Float64(x + 1.0)) - Float64(Float64(x + 1.0) / Float64(x - 1.0)))
end
function tmp = code(x)
	tmp = (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
end
code[x_] := N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x}{x + 1} - \frac{x + 1}{x - 1}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 10 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 54.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{x}{x + 1} - \frac{x + 1}{x - 1} \end{array} \]
(FPCore (x) :precision binary64 (- (/ x (+ x 1.0)) (/ (+ x 1.0) (- x 1.0))))
double code(double x) {
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x / (x + 1.0d0)) - ((x + 1.0d0) / (x - 1.0d0))
end function
public static double code(double x) {
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
}
def code(x):
	return (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0))
function code(x)
	return Float64(Float64(x / Float64(x + 1.0)) - Float64(Float64(x + 1.0) / Float64(x - 1.0)))
end
function tmp = code(x)
	tmp = (x / (x + 1.0)) - ((x + 1.0) / (x - 1.0));
end
code[x_] := N[(N[(x / N[(x + 1.0), $MachinePrecision]), $MachinePrecision] - N[(N[(x + 1.0), $MachinePrecision] / N[(x - 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{x}{x + 1} - \frac{x + 1}{x - 1}
\end{array}

Alternative 1: 99.6% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x} \leq 0:\\ \;\;\;\;\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(1 - x\right) + \frac{x + 1}{x} \cdot \left(x + 1\right)}{\left(x + -1\right) \cdot \frac{-1 - x}{x}}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= (- (/ (- -1.0 x) (+ x -1.0)) (/ x (- -1.0 x))) 0.0)
   (/ (- (/ (+ -1.0 (/ (+ -3.0 (/ -1.0 x)) x)) x) 3.0) x)
   (/
    (+ (- 1.0 x) (* (/ (+ x 1.0) x) (+ x 1.0)))
    (* (+ x -1.0) (/ (- -1.0 x) x)))))
double code(double x) {
	double tmp;
	if ((((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))) <= 0.0) {
		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x;
	} else {
		tmp = ((1.0 - x) + (((x + 1.0) / x) * (x + 1.0))) / ((x + -1.0) * ((-1.0 - x) / x));
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (((((-1.0d0) - x) / (x + (-1.0d0))) - (x / ((-1.0d0) - x))) <= 0.0d0) then
        tmp = ((((-1.0d0) + (((-3.0d0) + ((-1.0d0) / x)) / x)) / x) - 3.0d0) / x
    else
        tmp = ((1.0d0 - x) + (((x + 1.0d0) / x) * (x + 1.0d0))) / ((x + (-1.0d0)) * (((-1.0d0) - x) / x))
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if ((((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))) <= 0.0) {
		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x;
	} else {
		tmp = ((1.0 - x) + (((x + 1.0) / x) * (x + 1.0))) / ((x + -1.0) * ((-1.0 - x) / x));
	}
	return tmp;
}
def code(x):
	tmp = 0
	if (((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))) <= 0.0:
		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x
	else:
		tmp = ((1.0 - x) + (((x + 1.0) / x) * (x + 1.0))) / ((x + -1.0) * ((-1.0 - x) / x))
	return tmp
function code(x)
	tmp = 0.0
	if (Float64(Float64(Float64(-1.0 - x) / Float64(x + -1.0)) - Float64(x / Float64(-1.0 - x))) <= 0.0)
		tmp = Float64(Float64(Float64(Float64(-1.0 + Float64(Float64(-3.0 + Float64(-1.0 / x)) / x)) / x) - 3.0) / x);
	else
		tmp = Float64(Float64(Float64(1.0 - x) + Float64(Float64(Float64(x + 1.0) / x) * Float64(x + 1.0))) / Float64(Float64(x + -1.0) * Float64(Float64(-1.0 - x) / x)));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if ((((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))) <= 0.0)
		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x;
	else
		tmp = ((1.0 - x) + (((x + 1.0) / x) * (x + 1.0))) / ((x + -1.0) * ((-1.0 - x) / x));
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[N[(N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] - N[(x / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0], N[(N[(N[(N[(-1.0 + N[(N[(-3.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] - 3.0), $MachinePrecision] / x), $MachinePrecision], N[(N[(N[(1.0 - x), $MachinePrecision] + N[(N[(N[(x + 1.0), $MachinePrecision] / x), $MachinePrecision] * N[(x + 1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(x + -1.0), $MachinePrecision] * N[(N[(-1.0 - x), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x} \leq 0:\\
\;\;\;\;\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}\\

\mathbf{else}:\\
\;\;\;\;\frac{\left(1 - x\right) + \frac{x + 1}{x} \cdot \left(x + 1\right)}{\left(x + -1\right) \cdot \frac{-1 - x}{x}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 0.0

    1. Initial program 7.7%

      \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
    2. Step-by-step derivation
      1. remove-double-neg7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
      2. distribute-neg-in7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
      3. sub-neg7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
      4. distribute-frac-neg7.7%

        \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
      5. distribute-frac-neg27.7%

        \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
      6. sub-neg7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
      7. +-commutative7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
      8. unsub-neg7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
      9. metadata-eval7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
      10. neg-sub07.7%

        \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
      11. associate-+l-7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
      12. neg-sub07.7%

        \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
      13. +-commutative7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
      14. unsub-neg7.7%

        \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
    3. Simplified7.7%

      \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around inf 99.5%

      \[\leadsto \color{blue}{\frac{-1 \cdot \frac{3 + \frac{1}{x}}{{x}^{2}} - \left(3 + \frac{1}{x}\right)}{x}} \]
    6. Step-by-step derivation
      1. Simplified99.5%

        \[\leadsto \color{blue}{\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}} \]

      if 0.0 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

      1. Initial program 99.9%

        \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
      2. Step-by-step derivation
        1. remove-double-neg99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
        2. distribute-neg-in99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
        3. sub-neg99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
        4. distribute-frac-neg99.9%

          \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
        5. distribute-frac-neg299.9%

          \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
        6. sub-neg99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
        7. +-commutative99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
        8. unsub-neg99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
        9. metadata-eval99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
        10. neg-sub099.9%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
        11. associate-+l-99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
        12. neg-sub099.9%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
        13. +-commutative99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
        14. unsub-neg99.9%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
      3. Simplified99.9%

        \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
      4. Add Preprocessing
      5. Step-by-step derivation
        1. clear-num99.9%

          \[\leadsto \color{blue}{\frac{1}{\frac{x + 1}{x}}} - \frac{-1 - x}{1 - x} \]
        2. frac-sub99.9%

          \[\leadsto \color{blue}{\frac{1 \cdot \left(1 - x\right) - \frac{x + 1}{x} \cdot \left(-1 - x\right)}{\frac{x + 1}{x} \cdot \left(1 - x\right)}} \]
        3. *-un-lft-identity99.9%

          \[\leadsto \frac{\color{blue}{\left(1 - x\right)} - \frac{x + 1}{x} \cdot \left(-1 - x\right)}{\frac{x + 1}{x} \cdot \left(1 - x\right)} \]
      6. Applied egg-rr99.9%

        \[\leadsto \color{blue}{\frac{\left(1 - x\right) - \frac{x + 1}{x} \cdot \left(-1 - x\right)}{\frac{x + 1}{x} \cdot \left(1 - x\right)}} \]
    7. Recombined 2 regimes into one program.
    8. Final simplification99.7%

      \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x} \leq 0:\\ \;\;\;\;\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{\left(1 - x\right) + \frac{x + 1}{x} \cdot \left(x + 1\right)}{\left(x + -1\right) \cdot \frac{-1 - x}{x}}\\ \end{array} \]
    9. Add Preprocessing

    Alternative 2: 99.4% accurate, 0.4× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x} \leq 0:\\ \;\;\;\;\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{x \cdot \frac{x + -1}{-1 - x} + \left(x + 1\right)}{1 - x}\\ \end{array} \end{array} \]
    (FPCore (x)
     :precision binary64
     (if (<= (- (/ (- -1.0 x) (+ x -1.0)) (/ x (- -1.0 x))) 0.0)
       (/ (- (/ (+ -1.0 (/ (+ -3.0 (/ -1.0 x)) x)) x) 3.0) x)
       (/ (+ (* x (/ (+ x -1.0) (- -1.0 x))) (+ x 1.0)) (- 1.0 x))))
    double code(double x) {
    	double tmp;
    	if ((((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))) <= 0.0) {
    		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x;
    	} else {
    		tmp = ((x * ((x + -1.0) / (-1.0 - x))) + (x + 1.0)) / (1.0 - x);
    	}
    	return tmp;
    }
    
    real(8) function code(x)
        real(8), intent (in) :: x
        real(8) :: tmp
        if (((((-1.0d0) - x) / (x + (-1.0d0))) - (x / ((-1.0d0) - x))) <= 0.0d0) then
            tmp = ((((-1.0d0) + (((-3.0d0) + ((-1.0d0) / x)) / x)) / x) - 3.0d0) / x
        else
            tmp = ((x * ((x + (-1.0d0)) / ((-1.0d0) - x))) + (x + 1.0d0)) / (1.0d0 - x)
        end if
        code = tmp
    end function
    
    public static double code(double x) {
    	double tmp;
    	if ((((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))) <= 0.0) {
    		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x;
    	} else {
    		tmp = ((x * ((x + -1.0) / (-1.0 - x))) + (x + 1.0)) / (1.0 - x);
    	}
    	return tmp;
    }
    
    def code(x):
    	tmp = 0
    	if (((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))) <= 0.0:
    		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x
    	else:
    		tmp = ((x * ((x + -1.0) / (-1.0 - x))) + (x + 1.0)) / (1.0 - x)
    	return tmp
    
    function code(x)
    	tmp = 0.0
    	if (Float64(Float64(Float64(-1.0 - x) / Float64(x + -1.0)) - Float64(x / Float64(-1.0 - x))) <= 0.0)
    		tmp = Float64(Float64(Float64(Float64(-1.0 + Float64(Float64(-3.0 + Float64(-1.0 / x)) / x)) / x) - 3.0) / x);
    	else
    		tmp = Float64(Float64(Float64(x * Float64(Float64(x + -1.0) / Float64(-1.0 - x))) + Float64(x + 1.0)) / Float64(1.0 - x));
    	end
    	return tmp
    end
    
    function tmp_2 = code(x)
    	tmp = 0.0;
    	if ((((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))) <= 0.0)
    		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x;
    	else
    		tmp = ((x * ((x + -1.0) / (-1.0 - x))) + (x + 1.0)) / (1.0 - x);
    	end
    	tmp_2 = tmp;
    end
    
    code[x_] := If[LessEqual[N[(N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] - N[(x / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0], N[(N[(N[(N[(-1.0 + N[(N[(-3.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] - 3.0), $MachinePrecision] / x), $MachinePrecision], N[(N[(N[(x * N[(N[(x + -1.0), $MachinePrecision] / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(x + 1.0), $MachinePrecision]), $MachinePrecision] / N[(1.0 - x), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x} \leq 0:\\
    \;\;\;\;\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{x \cdot \frac{x + -1}{-1 - x} + \left(x + 1\right)}{1 - x}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 0.0

      1. Initial program 7.7%

        \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
      2. Step-by-step derivation
        1. remove-double-neg7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
        2. distribute-neg-in7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
        3. sub-neg7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
        4. distribute-frac-neg7.7%

          \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
        5. distribute-frac-neg27.7%

          \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
        6. sub-neg7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
        7. +-commutative7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
        8. unsub-neg7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
        9. metadata-eval7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
        10. neg-sub07.7%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
        11. associate-+l-7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
        12. neg-sub07.7%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
        13. +-commutative7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
        14. unsub-neg7.7%

          \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
      3. Simplified7.7%

        \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
      4. Add Preprocessing
      5. Taylor expanded in x around inf 99.5%

        \[\leadsto \color{blue}{\frac{-1 \cdot \frac{3 + \frac{1}{x}}{{x}^{2}} - \left(3 + \frac{1}{x}\right)}{x}} \]
      6. Step-by-step derivation
        1. Simplified99.5%

          \[\leadsto \color{blue}{\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}} \]

        if 0.0 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

        1. Initial program 99.9%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Step-by-step derivation
          1. remove-double-neg99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
          2. distribute-neg-in99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
          3. sub-neg99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
          4. distribute-frac-neg99.9%

            \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
          5. distribute-frac-neg299.9%

            \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
          6. sub-neg99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
          7. +-commutative99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
          8. unsub-neg99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
          9. metadata-eval99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
          10. neg-sub099.9%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
          11. associate-+l-99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
          12. neg-sub099.9%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
          13. +-commutative99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
          14. unsub-neg99.9%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
        3. Simplified99.9%

          \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
        4. Add Preprocessing
        5. Step-by-step derivation
          1. frac-2neg99.9%

            \[\leadsto \color{blue}{\frac{-x}{-\left(x + 1\right)}} - \frac{-1 - x}{1 - x} \]
          2. clear-num99.9%

            \[\leadsto \frac{-x}{-\left(x + 1\right)} - \color{blue}{\frac{1}{\frac{1 - x}{-1 - x}}} \]
          3. frac-sub99.9%

            \[\leadsto \color{blue}{\frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-\left(x + 1\right)\right) \cdot 1}{\left(-\left(x + 1\right)\right) \cdot \frac{1 - x}{-1 - x}}} \]
          4. +-commutative99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-\color{blue}{\left(1 + x\right)}\right) \cdot 1}{\left(-\left(x + 1\right)\right) \cdot \frac{1 - x}{-1 - x}} \]
          5. distribute-neg-in99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \color{blue}{\left(\left(-1\right) + \left(-x\right)\right)} \cdot 1}{\left(-\left(x + 1\right)\right) \cdot \frac{1 - x}{-1 - x}} \]
          6. metadata-eval99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(\color{blue}{-1} + \left(-x\right)\right) \cdot 1}{\left(-\left(x + 1\right)\right) \cdot \frac{1 - x}{-1 - x}} \]
          7. sub-neg99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \color{blue}{\left(-1 - x\right)} \cdot 1}{\left(-\left(x + 1\right)\right) \cdot \frac{1 - x}{-1 - x}} \]
          8. *-commutative99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \color{blue}{1 \cdot \left(-1 - x\right)}}{\left(-\left(x + 1\right)\right) \cdot \frac{1 - x}{-1 - x}} \]
          9. *-un-lft-identity99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \color{blue}{\left(-1 - x\right)}}{\left(-\left(x + 1\right)\right) \cdot \frac{1 - x}{-1 - x}} \]
          10. +-commutative99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-1 - x\right)}{\left(-\color{blue}{\left(1 + x\right)}\right) \cdot \frac{1 - x}{-1 - x}} \]
          11. distribute-neg-in99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-1 - x\right)}{\color{blue}{\left(\left(-1\right) + \left(-x\right)\right)} \cdot \frac{1 - x}{-1 - x}} \]
          12. metadata-eval99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-1 - x\right)}{\left(\color{blue}{-1} + \left(-x\right)\right) \cdot \frac{1 - x}{-1 - x}} \]
          13. sub-neg99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-1 - x\right)}{\color{blue}{\left(-1 - x\right)} \cdot \frac{1 - x}{-1 - x}} \]
        6. Applied egg-rr99.9%

          \[\leadsto \color{blue}{\frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-1 - x\right)}{\left(-1 - x\right) \cdot \frac{1 - x}{-1 - x}}} \]
        7. Taylor expanded in x around 0 99.9%

          \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-1 - x\right)}{\color{blue}{1 + -1 \cdot x}} \]
        8. Step-by-step derivation
          1. mul-1-neg99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-1 - x\right)}{1 + \color{blue}{\left(-x\right)}} \]
          2. unsub-neg99.9%

            \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-1 - x\right)}{\color{blue}{1 - x}} \]
        9. Simplified99.9%

          \[\leadsto \frac{\left(-x\right) \cdot \frac{1 - x}{-1 - x} - \left(-1 - x\right)}{\color{blue}{1 - x}} \]
      7. Recombined 2 regimes into one program.
      8. Final simplification99.7%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x} \leq 0:\\ \;\;\;\;\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{x \cdot \frac{x + -1}{-1 - x} + \left(x + 1\right)}{1 - x}\\ \end{array} \]
      9. Add Preprocessing

      Alternative 3: 99.3% accurate, 0.4× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{-1 - x}{x + -1} - \frac{x}{-1 - x}\\ \mathbf{if}\;t\_0 \leq 0:\\ \;\;\;\;\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
      (FPCore (x)
       :precision binary64
       (let* ((t_0 (- (/ (- -1.0 x) (+ x -1.0)) (/ x (- -1.0 x)))))
         (if (<= t_0 0.0)
           (/ (- (/ (+ -1.0 (/ (+ -3.0 (/ -1.0 x)) x)) x) 3.0) x)
           t_0)))
      double code(double x) {
      	double t_0 = ((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x));
      	double tmp;
      	if (t_0 <= 0.0) {
      		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x;
      	} 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) - x) / (x + (-1.0d0))) - (x / ((-1.0d0) - x))
          if (t_0 <= 0.0d0) then
              tmp = ((((-1.0d0) + (((-3.0d0) + ((-1.0d0) / x)) / x)) / x) - 3.0d0) / x
          else
              tmp = t_0
          end if
          code = tmp
      end function
      
      public static double code(double x) {
      	double t_0 = ((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x));
      	double tmp;
      	if (t_0 <= 0.0) {
      		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x;
      	} else {
      		tmp = t_0;
      	}
      	return tmp;
      }
      
      def code(x):
      	t_0 = ((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))
      	tmp = 0
      	if t_0 <= 0.0:
      		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x
      	else:
      		tmp = t_0
      	return tmp
      
      function code(x)
      	t_0 = Float64(Float64(Float64(-1.0 - x) / Float64(x + -1.0)) - Float64(x / Float64(-1.0 - x)))
      	tmp = 0.0
      	if (t_0 <= 0.0)
      		tmp = Float64(Float64(Float64(Float64(-1.0 + Float64(Float64(-3.0 + Float64(-1.0 / x)) / x)) / x) - 3.0) / x);
      	else
      		tmp = t_0;
      	end
      	return tmp
      end
      
      function tmp_2 = code(x)
      	t_0 = ((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x));
      	tmp = 0.0;
      	if (t_0 <= 0.0)
      		tmp = (((-1.0 + ((-3.0 + (-1.0 / x)) / x)) / x) - 3.0) / x;
      	else
      		tmp = t_0;
      	end
      	tmp_2 = tmp;
      end
      
      code[x_] := Block[{t$95$0 = N[(N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] - N[(x / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 0.0], N[(N[(N[(N[(-1.0 + N[(N[(-3.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] - 3.0), $MachinePrecision] / x), $MachinePrecision], t$95$0]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \frac{-1 - x}{x + -1} - \frac{x}{-1 - x}\\
      \mathbf{if}\;t\_0 \leq 0:\\
      \;\;\;\;\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}\\
      
      \mathbf{else}:\\
      \;\;\;\;t\_0\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 0.0

        1. Initial program 7.7%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Step-by-step derivation
          1. remove-double-neg7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
          2. distribute-neg-in7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
          3. sub-neg7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
          4. distribute-frac-neg7.7%

            \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
          5. distribute-frac-neg27.7%

            \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
          6. sub-neg7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
          7. +-commutative7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
          8. unsub-neg7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
          9. metadata-eval7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
          10. neg-sub07.7%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
          11. associate-+l-7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
          12. neg-sub07.7%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
          13. +-commutative7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
          14. unsub-neg7.7%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
        3. Simplified7.7%

          \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
        4. Add Preprocessing
        5. Taylor expanded in x around inf 99.5%

          \[\leadsto \color{blue}{\frac{-1 \cdot \frac{3 + \frac{1}{x}}{{x}^{2}} - \left(3 + \frac{1}{x}\right)}{x}} \]
        6. Step-by-step derivation
          1. Simplified99.5%

            \[\leadsto \color{blue}{\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}} \]

          if 0.0 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

          1. Initial program 99.9%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Add Preprocessing
        7. Recombined 2 regimes into one program.
        8. Final simplification99.7%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x} \leq 0:\\ \;\;\;\;\frac{\frac{-1 + \frac{-3 + \frac{-1}{x}}{x}}{x} - 3}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x}\\ \end{array} \]
        9. Add Preprocessing

        Alternative 4: 99.2% accurate, 0.4× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{-1 - x}{x + -1} - \frac{x}{-1 - x}\\ \mathbf{if}\;t\_0 \leq 0:\\ \;\;\;\;\frac{-3 + \frac{-1 + \frac{-3}{x}}{x}}{x}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (let* ((t_0 (- (/ (- -1.0 x) (+ x -1.0)) (/ x (- -1.0 x)))))
           (if (<= t_0 0.0) (/ (+ -3.0 (/ (+ -1.0 (/ -3.0 x)) x)) x) t_0)))
        double code(double x) {
        	double t_0 = ((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x));
        	double tmp;
        	if (t_0 <= 0.0) {
        		tmp = (-3.0 + ((-1.0 + (-3.0 / x)) / x)) / x;
        	} 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) - x) / (x + (-1.0d0))) - (x / ((-1.0d0) - x))
            if (t_0 <= 0.0d0) then
                tmp = ((-3.0d0) + (((-1.0d0) + ((-3.0d0) / x)) / x)) / x
            else
                tmp = t_0
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double t_0 = ((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x));
        	double tmp;
        	if (t_0 <= 0.0) {
        		tmp = (-3.0 + ((-1.0 + (-3.0 / x)) / x)) / x;
        	} else {
        		tmp = t_0;
        	}
        	return tmp;
        }
        
        def code(x):
        	t_0 = ((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x))
        	tmp = 0
        	if t_0 <= 0.0:
        		tmp = (-3.0 + ((-1.0 + (-3.0 / x)) / x)) / x
        	else:
        		tmp = t_0
        	return tmp
        
        function code(x)
        	t_0 = Float64(Float64(Float64(-1.0 - x) / Float64(x + -1.0)) - Float64(x / Float64(-1.0 - x)))
        	tmp = 0.0
        	if (t_0 <= 0.0)
        		tmp = Float64(Float64(-3.0 + Float64(Float64(-1.0 + Float64(-3.0 / x)) / x)) / x);
        	else
        		tmp = t_0;
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	t_0 = ((-1.0 - x) / (x + -1.0)) - (x / (-1.0 - x));
        	tmp = 0.0;
        	if (t_0 <= 0.0)
        		tmp = (-3.0 + ((-1.0 + (-3.0 / x)) / x)) / x;
        	else
        		tmp = t_0;
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := Block[{t$95$0 = N[(N[(N[(-1.0 - x), $MachinePrecision] / N[(x + -1.0), $MachinePrecision]), $MachinePrecision] - N[(x / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 0.0], N[(N[(-3.0 + N[(N[(-1.0 + N[(-3.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision], t$95$0]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        t_0 := \frac{-1 - x}{x + -1} - \frac{x}{-1 - x}\\
        \mathbf{if}\;t\_0 \leq 0:\\
        \;\;\;\;\frac{-3 + \frac{-1 + \frac{-3}{x}}{x}}{x}\\
        
        \mathbf{else}:\\
        \;\;\;\;t\_0\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64)))) < 0.0

          1. Initial program 7.7%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg27.7%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub07.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub07.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified7.7%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around inf 99.3%

            \[\leadsto \color{blue}{\frac{-1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x} - 3}{x}} \]
          6. Step-by-step derivation
            1. sub-neg99.3%

              \[\leadsto \frac{\color{blue}{-1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x} + \left(-3\right)}}{x} \]
            2. metadata-eval99.3%

              \[\leadsto \frac{-1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x} + \color{blue}{-3}}{x} \]
            3. +-commutative99.3%

              \[\leadsto \frac{\color{blue}{-3 + -1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x}}}{x} \]
            4. associate-*r/99.3%

              \[\leadsto \frac{-3 + \color{blue}{\frac{-1 \cdot \left(1 + 3 \cdot \frac{1}{x}\right)}{x}}}{x} \]
            5. distribute-lft-in99.3%

              \[\leadsto \frac{-3 + \frac{\color{blue}{-1 \cdot 1 + -1 \cdot \left(3 \cdot \frac{1}{x}\right)}}{x}}{x} \]
            6. metadata-eval99.3%

              \[\leadsto \frac{-3 + \frac{\color{blue}{-1} + -1 \cdot \left(3 \cdot \frac{1}{x}\right)}{x}}{x} \]
            7. neg-mul-199.3%

              \[\leadsto \frac{-3 + \frac{-1 + \color{blue}{\left(-3 \cdot \frac{1}{x}\right)}}{x}}{x} \]
            8. associate-*r/99.3%

              \[\leadsto \frac{-3 + \frac{-1 + \left(-\color{blue}{\frac{3 \cdot 1}{x}}\right)}{x}}{x} \]
            9. metadata-eval99.3%

              \[\leadsto \frac{-3 + \frac{-1 + \left(-\frac{\color{blue}{3}}{x}\right)}{x}}{x} \]
            10. distribute-neg-frac99.3%

              \[\leadsto \frac{-3 + \frac{-1 + \color{blue}{\frac{-3}{x}}}{x}}{x} \]
            11. metadata-eval99.3%

              \[\leadsto \frac{-3 + \frac{-1 + \frac{\color{blue}{-3}}{x}}{x}}{x} \]
          7. Simplified99.3%

            \[\leadsto \color{blue}{\frac{-3 + \frac{-1 + \frac{-3}{x}}{x}}{x}} \]

          if 0.0 < (-.f64 (/.f64 x (+.f64 x #s(literal 1 binary64))) (/.f64 (+.f64 x #s(literal 1 binary64)) (-.f64 x #s(literal 1 binary64))))

          1. Initial program 99.9%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Add Preprocessing
        3. Recombined 2 regimes into one program.
        4. Final simplification99.6%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x} \leq 0:\\ \;\;\;\;\frac{-3 + \frac{-1 + \frac{-3}{x}}{x}}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{-1 - x}{x + -1} - \frac{x}{-1 - x}\\ \end{array} \]
        5. Add Preprocessing

        Alternative 5: 99.0% accurate, 0.6× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{elif}\;x \leq 1:\\ \;\;\;\;1 + x \cdot \left(x + 3\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{-3 + \frac{-1 + \frac{-3}{x}}{x}}{x}\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x -1.0)
           (/ -3.0 x)
           (if (<= x 1.0)
             (+ 1.0 (* x (+ x 3.0)))
             (/ (+ -3.0 (/ (+ -1.0 (/ -3.0 x)) x)) x))))
        double code(double x) {
        	double tmp;
        	if (x <= -1.0) {
        		tmp = -3.0 / x;
        	} else if (x <= 1.0) {
        		tmp = 1.0 + (x * (x + 3.0));
        	} else {
        		tmp = (-3.0 + ((-1.0 + (-3.0 / x)) / x)) / x;
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if (x <= (-1.0d0)) then
                tmp = (-3.0d0) / x
            else if (x <= 1.0d0) then
                tmp = 1.0d0 + (x * (x + 3.0d0))
            else
                tmp = ((-3.0d0) + (((-1.0d0) + ((-3.0d0) / x)) / x)) / x
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if (x <= -1.0) {
        		tmp = -3.0 / x;
        	} else if (x <= 1.0) {
        		tmp = 1.0 + (x * (x + 3.0));
        	} else {
        		tmp = (-3.0 + ((-1.0 + (-3.0 / x)) / x)) / x;
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if x <= -1.0:
        		tmp = -3.0 / x
        	elif x <= 1.0:
        		tmp = 1.0 + (x * (x + 3.0))
        	else:
        		tmp = (-3.0 + ((-1.0 + (-3.0 / x)) / x)) / x
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if (x <= -1.0)
        		tmp = Float64(-3.0 / x);
        	elseif (x <= 1.0)
        		tmp = Float64(1.0 + Float64(x * Float64(x + 3.0)));
        	else
        		tmp = Float64(Float64(-3.0 + Float64(Float64(-1.0 + Float64(-3.0 / x)) / x)) / x);
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if (x <= -1.0)
        		tmp = -3.0 / x;
        	elseif (x <= 1.0)
        		tmp = 1.0 + (x * (x + 3.0));
        	else
        		tmp = (-3.0 + ((-1.0 + (-3.0 / x)) / x)) / x;
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[LessEqual[x, -1.0], N[(-3.0 / x), $MachinePrecision], If[LessEqual[x, 1.0], N[(1.0 + N[(x * N[(x + 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(-3.0 + N[(N[(-1.0 + N[(-3.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq -1:\\
        \;\;\;\;\frac{-3}{x}\\
        
        \mathbf{elif}\;x \leq 1:\\
        \;\;\;\;1 + x \cdot \left(x + 3\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\frac{-3 + \frac{-1 + \frac{-3}{x}}{x}}{x}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 3 regimes
        2. if x < -1

          1. Initial program 5.6%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg25.6%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub05.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub05.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified5.6%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around inf 100.0%

            \[\leadsto \color{blue}{\frac{-3}{x}} \]

          if -1 < x < 1

          1. Initial program 99.9%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg299.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified99.9%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around 0 98.2%

            \[\leadsto \color{blue}{1 + x \cdot \left(3 + x\right)} \]

          if 1 < x

          1. Initial program 9.6%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg29.6%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub09.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub09.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified9.6%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around inf 98.7%

            \[\leadsto \color{blue}{\frac{-1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x} - 3}{x}} \]
          6. Step-by-step derivation
            1. sub-neg98.7%

              \[\leadsto \frac{\color{blue}{-1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x} + \left(-3\right)}}{x} \]
            2. metadata-eval98.7%

              \[\leadsto \frac{-1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x} + \color{blue}{-3}}{x} \]
            3. +-commutative98.7%

              \[\leadsto \frac{\color{blue}{-3 + -1 \cdot \frac{1 + 3 \cdot \frac{1}{x}}{x}}}{x} \]
            4. associate-*r/98.7%

              \[\leadsto \frac{-3 + \color{blue}{\frac{-1 \cdot \left(1 + 3 \cdot \frac{1}{x}\right)}{x}}}{x} \]
            5. distribute-lft-in98.7%

              \[\leadsto \frac{-3 + \frac{\color{blue}{-1 \cdot 1 + -1 \cdot \left(3 \cdot \frac{1}{x}\right)}}{x}}{x} \]
            6. metadata-eval98.7%

              \[\leadsto \frac{-3 + \frac{\color{blue}{-1} + -1 \cdot \left(3 \cdot \frac{1}{x}\right)}{x}}{x} \]
            7. neg-mul-198.7%

              \[\leadsto \frac{-3 + \frac{-1 + \color{blue}{\left(-3 \cdot \frac{1}{x}\right)}}{x}}{x} \]
            8. associate-*r/98.7%

              \[\leadsto \frac{-3 + \frac{-1 + \left(-\color{blue}{\frac{3 \cdot 1}{x}}\right)}{x}}{x} \]
            9. metadata-eval98.7%

              \[\leadsto \frac{-3 + \frac{-1 + \left(-\frac{\color{blue}{3}}{x}\right)}{x}}{x} \]
            10. distribute-neg-frac98.7%

              \[\leadsto \frac{-3 + \frac{-1 + \color{blue}{\frac{-3}{x}}}{x}}{x} \]
            11. metadata-eval98.7%

              \[\leadsto \frac{-3 + \frac{-1 + \frac{\color{blue}{-3}}{x}}{x}}{x} \]
          7. Simplified98.7%

            \[\leadsto \color{blue}{\frac{-3 + \frac{-1 + \frac{-3}{x}}{x}}{x}} \]
        3. Recombined 3 regimes into one program.
        4. Final simplification98.8%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{elif}\;x \leq 1:\\ \;\;\;\;1 + x \cdot \left(x + 3\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{-3 + \frac{-1 + \frac{-3}{x}}{x}}{x}\\ \end{array} \]
        5. Add Preprocessing

        Alternative 6: 98.6% accurate, 0.8× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;1 + x \cdot \left(x + 3\right)\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (or (<= x -1.0) (not (<= x 1.0))) (/ -3.0 x) (+ 1.0 (* x (+ x 3.0)))))
        double code(double x) {
        	double tmp;
        	if ((x <= -1.0) || !(x <= 1.0)) {
        		tmp = -3.0 / x;
        	} else {
        		tmp = 1.0 + (x * (x + 3.0));
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if ((x <= (-1.0d0)) .or. (.not. (x <= 1.0d0))) then
                tmp = (-3.0d0) / x
            else
                tmp = 1.0d0 + (x * (x + 3.0d0))
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if ((x <= -1.0) || !(x <= 1.0)) {
        		tmp = -3.0 / x;
        	} else {
        		tmp = 1.0 + (x * (x + 3.0));
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if (x <= -1.0) or not (x <= 1.0):
        		tmp = -3.0 / x
        	else:
        		tmp = 1.0 + (x * (x + 3.0))
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if ((x <= -1.0) || !(x <= 1.0))
        		tmp = Float64(-3.0 / x);
        	else
        		tmp = Float64(1.0 + Float64(x * Float64(x + 3.0)));
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if ((x <= -1.0) || ~((x <= 1.0)))
        		tmp = -3.0 / x;
        	else
        		tmp = 1.0 + (x * (x + 3.0));
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[Or[LessEqual[x, -1.0], N[Not[LessEqual[x, 1.0]], $MachinePrecision]], N[(-3.0 / x), $MachinePrecision], N[(1.0 + N[(x * N[(x + 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\
        \;\;\;\;\frac{-3}{x}\\
        
        \mathbf{else}:\\
        \;\;\;\;1 + x \cdot \left(x + 3\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < -1 or 1 < x

          1. Initial program 7.7%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg27.7%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub07.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub07.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified7.7%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around inf 98.4%

            \[\leadsto \color{blue}{\frac{-3}{x}} \]

          if -1 < x < 1

          1. Initial program 99.9%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg299.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified99.9%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around 0 98.2%

            \[\leadsto \color{blue}{1 + x \cdot \left(3 + x\right)} \]
        3. Recombined 2 regimes into one program.
        4. Final simplification98.3%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;1 + x \cdot \left(x + 3\right)\\ \end{array} \]
        5. Add Preprocessing

        Alternative 7: 98.9% accurate, 0.8× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{elif}\;x \leq 1:\\ \;\;\;\;1 + x \cdot \left(x + 3\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{-3 + \frac{-1}{x}}{x}\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x -1.0)
           (/ -3.0 x)
           (if (<= x 1.0) (+ 1.0 (* x (+ x 3.0))) (/ (+ -3.0 (/ -1.0 x)) x))))
        double code(double x) {
        	double tmp;
        	if (x <= -1.0) {
        		tmp = -3.0 / x;
        	} else if (x <= 1.0) {
        		tmp = 1.0 + (x * (x + 3.0));
        	} else {
        		tmp = (-3.0 + (-1.0 / x)) / x;
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if (x <= (-1.0d0)) then
                tmp = (-3.0d0) / x
            else if (x <= 1.0d0) then
                tmp = 1.0d0 + (x * (x + 3.0d0))
            else
                tmp = ((-3.0d0) + ((-1.0d0) / x)) / x
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if (x <= -1.0) {
        		tmp = -3.0 / x;
        	} else if (x <= 1.0) {
        		tmp = 1.0 + (x * (x + 3.0));
        	} else {
        		tmp = (-3.0 + (-1.0 / x)) / x;
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if x <= -1.0:
        		tmp = -3.0 / x
        	elif x <= 1.0:
        		tmp = 1.0 + (x * (x + 3.0))
        	else:
        		tmp = (-3.0 + (-1.0 / x)) / x
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if (x <= -1.0)
        		tmp = Float64(-3.0 / x);
        	elseif (x <= 1.0)
        		tmp = Float64(1.0 + Float64(x * Float64(x + 3.0)));
        	else
        		tmp = Float64(Float64(-3.0 + Float64(-1.0 / x)) / x);
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if (x <= -1.0)
        		tmp = -3.0 / x;
        	elseif (x <= 1.0)
        		tmp = 1.0 + (x * (x + 3.0));
        	else
        		tmp = (-3.0 + (-1.0 / x)) / x;
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[LessEqual[x, -1.0], N[(-3.0 / x), $MachinePrecision], If[LessEqual[x, 1.0], N[(1.0 + N[(x * N[(x + 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(-3.0 + N[(-1.0 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq -1:\\
        \;\;\;\;\frac{-3}{x}\\
        
        \mathbf{elif}\;x \leq 1:\\
        \;\;\;\;1 + x \cdot \left(x + 3\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\frac{-3 + \frac{-1}{x}}{x}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 3 regimes
        2. if x < -1

          1. Initial program 5.6%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg25.6%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub05.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub05.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg5.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified5.6%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around inf 100.0%

            \[\leadsto \color{blue}{\frac{-3}{x}} \]

          if -1 < x < 1

          1. Initial program 99.9%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg299.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified99.9%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around 0 98.2%

            \[\leadsto \color{blue}{1 + x \cdot \left(3 + x\right)} \]

          if 1 < x

          1. Initial program 9.6%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg29.6%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub09.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub09.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg9.6%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified9.6%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around inf 97.9%

            \[\leadsto \color{blue}{-1 \cdot \frac{3 + \frac{1}{x}}{x}} \]
          6. Step-by-step derivation
            1. associate-*r/97.9%

              \[\leadsto \color{blue}{\frac{-1 \cdot \left(3 + \frac{1}{x}\right)}{x}} \]
            2. neg-mul-197.9%

              \[\leadsto \frac{\color{blue}{-\left(3 + \frac{1}{x}\right)}}{x} \]
            3. distribute-neg-in97.9%

              \[\leadsto \frac{\color{blue}{\left(-3\right) + \left(-\frac{1}{x}\right)}}{x} \]
            4. metadata-eval97.9%

              \[\leadsto \frac{\color{blue}{-3} + \left(-\frac{1}{x}\right)}{x} \]
            5. unsub-neg97.9%

              \[\leadsto \frac{\color{blue}{-3 - \frac{1}{x}}}{x} \]
          7. Simplified97.9%

            \[\leadsto \color{blue}{\frac{-3 - \frac{1}{x}}{x}} \]
        3. Recombined 3 regimes into one program.
        4. Final simplification98.6%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1:\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{elif}\;x \leq 1:\\ \;\;\;\;1 + x \cdot \left(x + 3\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{-3 + \frac{-1}{x}}{x}\\ \end{array} \]
        5. Add Preprocessing

        Alternative 8: 98.5% accurate, 0.9× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;1 + x \cdot 3\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (or (<= x -1.0) (not (<= x 1.0))) (/ -3.0 x) (+ 1.0 (* x 3.0))))
        double code(double x) {
        	double tmp;
        	if ((x <= -1.0) || !(x <= 1.0)) {
        		tmp = -3.0 / x;
        	} else {
        		tmp = 1.0 + (x * 3.0);
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if ((x <= (-1.0d0)) .or. (.not. (x <= 1.0d0))) then
                tmp = (-3.0d0) / x
            else
                tmp = 1.0d0 + (x * 3.0d0)
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if ((x <= -1.0) || !(x <= 1.0)) {
        		tmp = -3.0 / x;
        	} else {
        		tmp = 1.0 + (x * 3.0);
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if (x <= -1.0) or not (x <= 1.0):
        		tmp = -3.0 / x
        	else:
        		tmp = 1.0 + (x * 3.0)
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if ((x <= -1.0) || !(x <= 1.0))
        		tmp = Float64(-3.0 / x);
        	else
        		tmp = Float64(1.0 + Float64(x * 3.0));
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if ((x <= -1.0) || ~((x <= 1.0)))
        		tmp = -3.0 / x;
        	else
        		tmp = 1.0 + (x * 3.0);
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[Or[LessEqual[x, -1.0], N[Not[LessEqual[x, 1.0]], $MachinePrecision]], N[(-3.0 / x), $MachinePrecision], N[(1.0 + N[(x * 3.0), $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\
        \;\;\;\;\frac{-3}{x}\\
        
        \mathbf{else}:\\
        \;\;\;\;1 + x \cdot 3\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < -1 or 1 < x

          1. Initial program 7.7%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg27.7%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub07.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub07.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified7.7%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around inf 98.4%

            \[\leadsto \color{blue}{\frac{-3}{x}} \]

          if -1 < x < 1

          1. Initial program 99.9%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg299.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified99.9%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around 0 97.4%

            \[\leadsto \color{blue}{1 + 3 \cdot x} \]
        3. Recombined 2 regimes into one program.
        4. Final simplification97.9%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;1 + x \cdot 3\\ \end{array} \]
        5. Add Preprocessing

        Alternative 9: 97.9% accurate, 1.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;x + 1\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (or (<= x -1.0) (not (<= x 1.0))) (/ -3.0 x) (+ x 1.0)))
        double code(double x) {
        	double tmp;
        	if ((x <= -1.0) || !(x <= 1.0)) {
        		tmp = -3.0 / x;
        	} else {
        		tmp = x + 1.0;
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if ((x <= (-1.0d0)) .or. (.not. (x <= 1.0d0))) then
                tmp = (-3.0d0) / x
            else
                tmp = x + 1.0d0
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if ((x <= -1.0) || !(x <= 1.0)) {
        		tmp = -3.0 / x;
        	} else {
        		tmp = x + 1.0;
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if (x <= -1.0) or not (x <= 1.0):
        		tmp = -3.0 / x
        	else:
        		tmp = x + 1.0
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if ((x <= -1.0) || !(x <= 1.0))
        		tmp = Float64(-3.0 / x);
        	else
        		tmp = Float64(x + 1.0);
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if ((x <= -1.0) || ~((x <= 1.0)))
        		tmp = -3.0 / x;
        	else
        		tmp = x + 1.0;
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[Or[LessEqual[x, -1.0], N[Not[LessEqual[x, 1.0]], $MachinePrecision]], N[(-3.0 / x), $MachinePrecision], N[(x + 1.0), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\
        \;\;\;\;\frac{-3}{x}\\
        
        \mathbf{else}:\\
        \;\;\;\;x + 1\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < -1 or 1 < x

          1. Initial program 7.7%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg27.7%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub07.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub07.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg7.7%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified7.7%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around inf 98.4%

            \[\leadsto \color{blue}{\frac{-3}{x}} \]

          if -1 < x < 1

          1. Initial program 99.9%

            \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
          2. Step-by-step derivation
            1. remove-double-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
            2. distribute-neg-in99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
            3. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
            4. distribute-frac-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
            5. distribute-frac-neg299.9%

              \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
            6. sub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
            7. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
            8. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
            9. metadata-eval99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
            10. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
            11. associate-+l-99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
            12. neg-sub099.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
            13. +-commutative99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
            14. unsub-neg99.9%

              \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
          3. Simplified99.9%

            \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
          4. Add Preprocessing
          5. Taylor expanded in x around 0 97.4%

            \[\leadsto \color{blue}{x} - \frac{-1 - x}{1 - x} \]
          6. Taylor expanded in x around 0 95.1%

            \[\leadsto x - \color{blue}{-1} \]
        3. Recombined 2 regimes into one program.
        4. Final simplification96.9%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1 \lor \neg \left(x \leq 1\right):\\ \;\;\;\;\frac{-3}{x}\\ \mathbf{else}:\\ \;\;\;\;x + 1\\ \end{array} \]
        5. Add Preprocessing

        Alternative 10: 51.0% accurate, 13.0× speedup?

        \[\begin{array}{l} \\ 1 \end{array} \]
        (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}
        
        Derivation
        1. Initial program 50.6%

          \[\frac{x}{x + 1} - \frac{x + 1}{x - 1} \]
        2. Step-by-step derivation
          1. remove-double-neg50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-\left(-\left(x + 1\right)\right)}}{x - 1} \]
          2. distribute-neg-in50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}}{x - 1} \]
          3. sub-neg50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{-\color{blue}{\left(\left(-x\right) - 1\right)}}{x - 1} \]
          4. distribute-frac-neg50.6%

            \[\leadsto \frac{x}{x + 1} - \color{blue}{\left(-\frac{\left(-x\right) - 1}{x - 1}\right)} \]
          5. distribute-frac-neg250.6%

            \[\leadsto \frac{x}{x + 1} - \color{blue}{\frac{\left(-x\right) - 1}{-\left(x - 1\right)}} \]
          6. sub-neg50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-x\right) + \left(-1\right)}}{-\left(x - 1\right)} \]
          7. +-commutative50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) + \left(-x\right)}}{-\left(x - 1\right)} \]
          8. unsub-neg50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{\left(-1\right) - x}}{-\left(x - 1\right)} \]
          9. metadata-eval50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{\color{blue}{-1} - x}{-\left(x - 1\right)} \]
          10. neg-sub050.6%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{0 - \left(x - 1\right)}} \]
          11. associate-+l-50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(0 - x\right) + 1}} \]
          12. neg-sub050.6%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{\left(-x\right)} + 1} \]
          13. +-commutative50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 + \left(-x\right)}} \]
          14. unsub-neg50.6%

            \[\leadsto \frac{x}{x + 1} - \frac{-1 - x}{\color{blue}{1 - x}} \]
        3. Simplified50.6%

          \[\leadsto \color{blue}{\frac{x}{x + 1} - \frac{-1 - x}{1 - x}} \]
        4. Add Preprocessing
        5. Taylor expanded in x around 0 46.1%

          \[\leadsto \color{blue}{1} \]
        6. Final simplification46.1%

          \[\leadsto 1 \]
        7. Add Preprocessing

        Reproduce

        ?
        herbie shell --seed 2024115 
        (FPCore (x)
          :name "Asymptote C"
          :precision binary64
          (- (/ x (+ x 1.0)) (/ (+ x 1.0) (- x 1.0))))