Asymptote A

Percentage Accurate: 77.5% → 99.4%
Time: 8.3s
Alternatives: 5
Speedup: 1.2×

Specification

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

\\
\frac{1}{x + 1} - \frac{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 5 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: 77.5% accurate, 1.0× speedup?

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

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

Alternative 1: 99.4% accurate, 1.2× speedup?

\[\begin{array}{l} \\ \frac{-2}{\left(1 - x\right) \cdot \left(-1 - x\right)} \end{array} \]
(FPCore (x) :precision binary64 (/ -2.0 (* (- 1.0 x) (- -1.0 x))))
double code(double x) {
	return -2.0 / ((1.0 - x) * (-1.0 - x));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (-2.0d0) / ((1.0d0 - x) * ((-1.0d0) - x))
end function
public static double code(double x) {
	return -2.0 / ((1.0 - x) * (-1.0 - x));
}
def code(x):
	return -2.0 / ((1.0 - x) * (-1.0 - x))
function code(x)
	return Float64(-2.0 / Float64(Float64(1.0 - x) * Float64(-1.0 - x)))
end
function tmp = code(x)
	tmp = -2.0 / ((1.0 - x) * (-1.0 - x));
end
code[x_] := N[(-2.0 / N[(N[(1.0 - x), $MachinePrecision] * N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{-2}{\left(1 - x\right) \cdot \left(-1 - x\right)}
\end{array}
Derivation
  1. Initial program 74.6%

    \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-neg74.6%

      \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
    2. +-commutative74.6%

      \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
    3. distribute-neg-frac274.6%

      \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
    4. neg-sub074.6%

      \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
    5. associate-+l-74.6%

      \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
    6. neg-sub074.6%

      \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
    7. remove-double-neg74.6%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
    8. distribute-neg-in74.6%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
    9. sub-neg74.6%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
    10. distribute-neg-frac274.6%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
    11. sub-neg74.6%

      \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
    12. +-commutative74.6%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
    13. unsub-neg74.6%

      \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
    14. sub-neg74.6%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
    15. +-commutative74.6%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
    16. unsub-neg74.6%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
    17. metadata-eval74.6%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
  3. Simplified74.6%

    \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. sub-neg74.6%

      \[\leadsto \color{blue}{\frac{1}{1 - x} + \left(-\frac{1}{-1 - x}\right)} \]
    2. distribute-neg-frac74.6%

      \[\leadsto \frac{1}{1 - x} + \color{blue}{\frac{-1}{-1 - x}} \]
    3. metadata-eval74.6%

      \[\leadsto \frac{1}{1 - x} + \frac{\color{blue}{-1}}{-1 - x} \]
  6. Applied egg-rr74.6%

    \[\leadsto \color{blue}{\frac{1}{1 - x} + \frac{-1}{-1 - x}} \]
  7. Simplified99.5%

    \[\leadsto \color{blue}{\frac{-2}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
  8. Final simplification99.5%

    \[\leadsto \frac{-2}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
  9. Add Preprocessing

Alternative 2: 74.7% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.75:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;\frac{-2}{x \cdot \left(x + -1\right)}\\ \end{array} \end{array} \]
(FPCore (x) :precision binary64 (if (<= x 0.75) 2.0 (/ -2.0 (* x (+ x -1.0)))))
double code(double x) {
	double tmp;
	if (x <= 0.75) {
		tmp = 2.0;
	} else {
		tmp = -2.0 / (x * (x + -1.0));
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 0.75d0) then
        tmp = 2.0d0
    else
        tmp = (-2.0d0) / (x * (x + (-1.0d0)))
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 0.75) {
		tmp = 2.0;
	} else {
		tmp = -2.0 / (x * (x + -1.0));
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 0.75:
		tmp = 2.0
	else:
		tmp = -2.0 / (x * (x + -1.0))
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 0.75)
		tmp = 2.0;
	else
		tmp = Float64(-2.0 / Float64(x * Float64(x + -1.0)));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 0.75)
		tmp = 2.0;
	else
		tmp = -2.0 / (x * (x + -1.0));
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 0.75], 2.0, N[(-2.0 / N[(x * N[(x + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.75:\\
\;\;\;\;2\\

\mathbf{else}:\\
\;\;\;\;\frac{-2}{x \cdot \left(x + -1\right)}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.75

    1. Initial program 82.9%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg82.9%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative82.9%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac282.9%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub082.9%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-82.9%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub082.9%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg82.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in82.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg82.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac282.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg82.9%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative82.9%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg82.9%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified82.9%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 64.9%

      \[\leadsto \color{blue}{2} \]

    if 0.75 < x

    1. Initial program 49.3%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg49.3%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative49.3%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac249.3%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub049.3%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-49.3%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub049.3%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg49.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in49.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg49.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac249.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg49.3%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative49.3%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg49.3%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified49.3%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. sub-neg49.3%

        \[\leadsto \color{blue}{\frac{1}{1 - x} + \left(-\frac{1}{-1 - x}\right)} \]
      2. distribute-neg-frac49.3%

        \[\leadsto \frac{1}{1 - x} + \color{blue}{\frac{-1}{-1 - x}} \]
      3. metadata-eval49.3%

        \[\leadsto \frac{1}{1 - x} + \frac{\color{blue}{-1}}{-1 - x} \]
    6. Applied egg-rr49.3%

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

      \[\leadsto \color{blue}{\frac{-2}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
    8. Step-by-step derivation
      1. flip3--45.0%

        \[\leadsto \frac{-2}{\left(1 - x\right) \cdot \color{blue}{\frac{{-1}^{3} - {x}^{3}}{-1 \cdot -1 + \left(x \cdot x + -1 \cdot x\right)}}} \]
      2. associate-*r/34.4%

        \[\leadsto \frac{-2}{\color{blue}{\frac{\left(1 - x\right) \cdot \left({-1}^{3} - {x}^{3}\right)}{-1 \cdot -1 + \left(x \cdot x + -1 \cdot x\right)}}} \]
      3. metadata-eval34.4%

        \[\leadsto \frac{-2}{\frac{\left(1 - x\right) \cdot \left(\color{blue}{-1} - {x}^{3}\right)}{-1 \cdot -1 + \left(x \cdot x + -1 \cdot x\right)}} \]
      4. metadata-eval34.4%

        \[\leadsto \frac{-2}{\frac{\left(1 - x\right) \cdot \left(-1 - {x}^{3}\right)}{\color{blue}{1} + \left(x \cdot x + -1 \cdot x\right)}} \]
      5. distribute-rgt-out34.4%

        \[\leadsto \frac{-2}{\frac{\left(1 - x\right) \cdot \left(-1 - {x}^{3}\right)}{1 + \color{blue}{x \cdot \left(x + -1\right)}}} \]
    9. Applied egg-rr34.4%

      \[\leadsto \frac{-2}{\color{blue}{\frac{\left(1 - x\right) \cdot \left(-1 - {x}^{3}\right)}{1 + x \cdot \left(x + -1\right)}}} \]
    10. Step-by-step derivation
      1. associate-/l*45.0%

        \[\leadsto \frac{-2}{\color{blue}{\left(1 - x\right) \cdot \frac{-1 - {x}^{3}}{1 + x \cdot \left(x + -1\right)}}} \]
    11. Simplified45.0%

      \[\leadsto \frac{-2}{\color{blue}{\left(1 - x\right) \cdot \frac{-1 - {x}^{3}}{1 + x \cdot \left(x + -1\right)}}} \]
    12. Taylor expanded in x around inf 98.3%

      \[\leadsto \frac{-2}{\left(1 - x\right) \cdot \color{blue}{\left(-1 \cdot x\right)}} \]
    13. Step-by-step derivation
      1. neg-mul-198.3%

        \[\leadsto \frac{-2}{\left(1 - x\right) \cdot \color{blue}{\left(-x\right)}} \]
    14. Simplified98.3%

      \[\leadsto \frac{-2}{\left(1 - x\right) \cdot \color{blue}{\left(-x\right)}} \]
    15. Taylor expanded in x around 0 98.3%

      \[\leadsto \frac{-2}{\color{blue}{x \cdot \left(x - 1\right)}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification73.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.75:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;\frac{-2}{x \cdot \left(x + -1\right)}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 75.0% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{2}{x}}{-1 - x}\\ \end{array} \end{array} \]
(FPCore (x) :precision binary64 (if (<= x 1.0) 2.0 (/ (/ 2.0 x) (- -1.0 x))))
double code(double x) {
	double tmp;
	if (x <= 1.0) {
		tmp = 2.0;
	} else {
		tmp = (2.0 / x) / (-1.0 - x);
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 1.0d0) then
        tmp = 2.0d0
    else
        tmp = (2.0d0 / x) / ((-1.0d0) - x)
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 1.0) {
		tmp = 2.0;
	} else {
		tmp = (2.0 / x) / (-1.0 - x);
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 1.0:
		tmp = 2.0
	else:
		tmp = (2.0 / x) / (-1.0 - x)
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 1.0)
		tmp = 2.0;
	else
		tmp = Float64(Float64(2.0 / x) / Float64(-1.0 - x));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 1.0)
		tmp = 2.0;
	else
		tmp = (2.0 / x) / (-1.0 - x);
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 1.0], 2.0, N[(N[(2.0 / x), $MachinePrecision] / N[(-1.0 - x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;2\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{2}{x}}{-1 - x}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1

    1. Initial program 82.9%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg82.9%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative82.9%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac282.9%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub082.9%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-82.9%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub082.9%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg82.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in82.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg82.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac282.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg82.9%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative82.9%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg82.9%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified82.9%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 64.9%

      \[\leadsto \color{blue}{2} \]

    if 1 < x

    1. Initial program 49.3%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg49.3%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative49.3%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac249.3%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub049.3%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-49.3%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub049.3%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg49.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in49.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg49.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac249.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg49.3%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative49.3%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg49.3%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified49.3%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. frac-sub50.4%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
      2. *-rgt-identity50.4%

        \[\leadsto \frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\color{blue}{\left(\left(1 - x\right) \cdot 1\right)} \cdot \left(-1 - x\right)} \]
      3. metadata-eval50.4%

        \[\leadsto \frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\left(\left(1 - x\right) \cdot \color{blue}{\frac{1}{1}}\right) \cdot \left(-1 - x\right)} \]
      4. div-inv50.4%

        \[\leadsto \frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\color{blue}{\frac{1 - x}{1}} \cdot \left(-1 - x\right)} \]
      5. associate-/r*50.4%

        \[\leadsto \color{blue}{\frac{\frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\frac{1 - x}{1}}}{-1 - x}} \]
      6. metadata-eval50.4%

        \[\leadsto \frac{\frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot \color{blue}{\frac{1}{1}}}{\frac{1 - x}{1}}}{-1 - x} \]
      7. div-inv50.4%

        \[\leadsto \frac{\frac{1 \cdot \left(-1 - x\right) - \color{blue}{\frac{1 - x}{1}}}{\frac{1 - x}{1}}}{-1 - x} \]
      8. *-un-lft-identity50.4%

        \[\leadsto \frac{\frac{\color{blue}{\left(-1 - x\right)} - \frac{1 - x}{1}}{\frac{1 - x}{1}}}{-1 - x} \]
      9. associate--l-57.5%

        \[\leadsto \frac{\frac{\color{blue}{-1 - \left(x + \frac{1 - x}{1}\right)}}{\frac{1 - x}{1}}}{-1 - x} \]
      10. div-inv57.5%

        \[\leadsto \frac{\frac{-1 - \left(x + \color{blue}{\left(1 - x\right) \cdot \frac{1}{1}}\right)}{\frac{1 - x}{1}}}{-1 - x} \]
      11. metadata-eval57.5%

        \[\leadsto \frac{\frac{-1 - \left(x + \left(1 - x\right) \cdot \color{blue}{1}\right)}{\frac{1 - x}{1}}}{-1 - x} \]
      12. *-rgt-identity57.5%

        \[\leadsto \frac{\frac{-1 - \left(x + \color{blue}{\left(1 - x\right)}\right)}{\frac{1 - x}{1}}}{-1 - x} \]
      13. div-inv57.5%

        \[\leadsto \frac{\frac{-1 - \left(x + \left(1 - x\right)\right)}{\color{blue}{\left(1 - x\right) \cdot \frac{1}{1}}}}{-1 - x} \]
      14. metadata-eval57.5%

        \[\leadsto \frac{\frac{-1 - \left(x + \left(1 - x\right)\right)}{\left(1 - x\right) \cdot \color{blue}{1}}}{-1 - x} \]
      15. *-rgt-identity57.5%

        \[\leadsto \frac{\frac{-1 - \left(x + \left(1 - x\right)\right)}{\color{blue}{1 - x}}}{-1 - x} \]
    6. Applied egg-rr57.5%

      \[\leadsto \color{blue}{\frac{\frac{-1 - \left(x + \left(1 - x\right)\right)}{1 - x}}{-1 - x}} \]
    7. Taylor expanded in x around inf 98.3%

      \[\leadsto \frac{\color{blue}{\frac{2}{x}}}{-1 - x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification73.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{2}{x}}{-1 - x}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 62.9% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \end{array} \]
(FPCore (x) :precision binary64 (if (<= x 1.0) 2.0 0.0))
double code(double x) {
	double tmp;
	if (x <= 1.0) {
		tmp = 2.0;
	} else {
		tmp = 0.0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 1.0d0) then
        tmp = 2.0d0
    else
        tmp = 0.0d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 1.0) {
		tmp = 2.0;
	} else {
		tmp = 0.0;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 1.0:
		tmp = 2.0
	else:
		tmp = 0.0
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 1.0)
		tmp = 2.0;
	else
		tmp = 0.0;
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 1.0)
		tmp = 2.0;
	else
		tmp = 0.0;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 1.0], 2.0, 0.0]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 1:\\
\;\;\;\;2\\

\mathbf{else}:\\
\;\;\;\;0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1

    1. Initial program 82.9%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg82.9%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative82.9%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac282.9%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub082.9%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-82.9%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub082.9%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg82.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in82.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg82.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac282.9%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg82.9%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative82.9%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg82.9%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval82.9%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified82.9%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 64.9%

      \[\leadsto \color{blue}{2} \]

    if 1 < x

    1. Initial program 49.3%

      \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
    2. Step-by-step derivation
      1. sub-neg49.3%

        \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
      2. +-commutative49.3%

        \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
      3. distribute-neg-frac249.3%

        \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
      4. neg-sub049.3%

        \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
      5. associate-+l-49.3%

        \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
      6. neg-sub049.3%

        \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
      7. remove-double-neg49.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
      8. distribute-neg-in49.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
      9. sub-neg49.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
      10. distribute-neg-frac249.3%

        \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
      11. sub-neg49.3%

        \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
      12. +-commutative49.3%

        \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
      13. unsub-neg49.3%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
      14. sub-neg49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
      15. +-commutative49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
      16. unsub-neg49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
      17. metadata-eval49.3%

        \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
    3. Simplified49.3%

      \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. flip--8.1%

        \[\leadsto \frac{1}{\color{blue}{\frac{1 \cdot 1 - x \cdot x}{1 + x}}} - \frac{1}{-1 - x} \]
      2. metadata-eval8.1%

        \[\leadsto \frac{1}{\frac{\color{blue}{1} - x \cdot x}{1 + x}} - \frac{1}{-1 - x} \]
      3. metadata-eval8.1%

        \[\leadsto \frac{1}{\frac{\color{blue}{-1 \cdot -1} - x \cdot x}{1 + x}} - \frac{1}{-1 - x} \]
      4. associate-/r/8.1%

        \[\leadsto \color{blue}{\frac{1}{-1 \cdot -1 - x \cdot x} \cdot \left(1 + x\right)} - \frac{1}{-1 - x} \]
      5. metadata-eval8.1%

        \[\leadsto \frac{1}{\color{blue}{1} - x \cdot x} \cdot \left(1 + x\right) - \frac{1}{-1 - x} \]
      6. pow28.1%

        \[\leadsto \frac{1}{1 - \color{blue}{{x}^{2}}} \cdot \left(1 + x\right) - \frac{1}{-1 - x} \]
    6. Applied egg-rr8.1%

      \[\leadsto \color{blue}{\frac{1}{1 - {x}^{2}} \cdot \left(1 + x\right)} - \frac{1}{-1 - x} \]
    7. Step-by-step derivation
      1. associate-*l/8.2%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(1 + x\right)}{1 - {x}^{2}}} - \frac{1}{-1 - x} \]
      2. *-lft-identity8.2%

        \[\leadsto \frac{\color{blue}{1 + x}}{1 - {x}^{2}} - \frac{1}{-1 - x} \]
      3. +-commutative8.2%

        \[\leadsto \frac{\color{blue}{x + 1}}{1 - {x}^{2}} - \frac{1}{-1 - x} \]
    8. Simplified8.2%

      \[\leadsto \color{blue}{\frac{x + 1}{1 - {x}^{2}}} - \frac{1}{-1 - x} \]
    9. Step-by-step derivation
      1. clear-num8.1%

        \[\leadsto \color{blue}{\frac{1}{\frac{1 - {x}^{2}}{x + 1}}} - \frac{1}{-1 - x} \]
      2. metadata-eval8.1%

        \[\leadsto \frac{1}{\frac{\color{blue}{1 \cdot 1} - {x}^{2}}{x + 1}} - \frac{1}{-1 - x} \]
      3. unpow28.1%

        \[\leadsto \frac{1}{\frac{1 \cdot 1 - \color{blue}{x \cdot x}}{x + 1}} - \frac{1}{-1 - x} \]
      4. +-commutative8.1%

        \[\leadsto \frac{1}{\frac{1 \cdot 1 - x \cdot x}{\color{blue}{1 + x}}} - \frac{1}{-1 - x} \]
      5. flip--49.3%

        \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{-1 - x} \]
      6. frac-sub50.4%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
      7. *-commutative50.4%

        \[\leadsto \frac{1 \cdot \left(-1 - x\right) - \color{blue}{1 \cdot \left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      8. distribute-lft-out--50.4%

        \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(-1 - x\right) - \left(1 - x\right)\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      9. associate--r+57.5%

        \[\leadsto \frac{1 \cdot \color{blue}{\left(-1 - \left(x + \left(1 - x\right)\right)\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      10. flip--54.3%

        \[\leadsto \frac{1 \cdot \color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{-1 + \left(x + \left(1 - x\right)\right)}}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      11. *-un-lft-identity54.3%

        \[\leadsto \frac{\color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{-1 + \left(x + \left(1 - x\right)\right)}}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
      12. associate-/l/54.3%

        \[\leadsto \color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)}} \]
    10. Applied egg-rr0.0%

      \[\leadsto \color{blue}{\frac{1 - {\left(1 + \left(x - x\right)\right)}^{2}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)}} \]
    11. Step-by-step derivation
      1. div-sub0.0%

        \[\leadsto \color{blue}{\frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{{\left(1 + \left(x - x\right)\right)}^{2}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)}} \]
      2. unpow20.0%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{\color{blue}{\left(1 + \left(x - x\right)\right) \cdot \left(1 + \left(x - x\right)\right)}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
      3. +-inverses0.0%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{\left(1 + \color{blue}{0}\right) \cdot \left(1 + \left(x - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
      4. metadata-eval0.0%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{\color{blue}{1} \cdot \left(1 + \left(x - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
      5. +-inverses0.0%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{1 \cdot \left(1 + \color{blue}{0}\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
      6. metadata-eval0.0%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{1 \cdot \color{blue}{1}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
      7. metadata-eval0.0%

        \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{\color{blue}{1}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
      8. +-inverses47.0%

        \[\leadsto \color{blue}{0} \]
    12. Simplified47.0%

      \[\leadsto \color{blue}{0} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification60.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 1:\\ \;\;\;\;2\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 27.4% accurate, 11.0× speedup?

\[\begin{array}{l} \\ 0 \end{array} \]
(FPCore (x) :precision binary64 0.0)
double code(double x) {
	return 0.0;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 0.0d0
end function
public static double code(double x) {
	return 0.0;
}
def code(x):
	return 0.0
function code(x)
	return 0.0
end
function tmp = code(x)
	tmp = 0.0;
end
code[x_] := 0.0
\begin{array}{l}

\\
0
\end{array}
Derivation
  1. Initial program 74.6%

    \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
  2. Step-by-step derivation
    1. sub-neg74.6%

      \[\leadsto \color{blue}{\frac{1}{x + 1} + \left(-\frac{1}{x - 1}\right)} \]
    2. +-commutative74.6%

      \[\leadsto \color{blue}{\left(-\frac{1}{x - 1}\right) + \frac{1}{x + 1}} \]
    3. distribute-neg-frac274.6%

      \[\leadsto \color{blue}{\frac{1}{-\left(x - 1\right)}} + \frac{1}{x + 1} \]
    4. neg-sub074.6%

      \[\leadsto \frac{1}{\color{blue}{0 - \left(x - 1\right)}} + \frac{1}{x + 1} \]
    5. associate-+l-74.6%

      \[\leadsto \frac{1}{\color{blue}{\left(0 - x\right) + 1}} + \frac{1}{x + 1} \]
    6. neg-sub074.6%

      \[\leadsto \frac{1}{\color{blue}{\left(-x\right)} + 1} + \frac{1}{x + 1} \]
    7. remove-double-neg74.6%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{\color{blue}{-\left(-\left(x + 1\right)\right)}} \]
    8. distribute-neg-in74.6%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) + \left(-1\right)\right)}} \]
    9. sub-neg74.6%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \frac{1}{-\color{blue}{\left(\left(-x\right) - 1\right)}} \]
    10. distribute-neg-frac274.6%

      \[\leadsto \frac{1}{\left(-x\right) + 1} + \color{blue}{\left(-\frac{1}{\left(-x\right) - 1}\right)} \]
    11. sub-neg74.6%

      \[\leadsto \color{blue}{\frac{1}{\left(-x\right) + 1} - \frac{1}{\left(-x\right) - 1}} \]
    12. +-commutative74.6%

      \[\leadsto \frac{1}{\color{blue}{1 + \left(-x\right)}} - \frac{1}{\left(-x\right) - 1} \]
    13. unsub-neg74.6%

      \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{\left(-x\right) - 1} \]
    14. sub-neg74.6%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-x\right) + \left(-1\right)}} \]
    15. +-commutative74.6%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) + \left(-x\right)}} \]
    16. unsub-neg74.6%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{\left(-1\right) - x}} \]
    17. metadata-eval74.6%

      \[\leadsto \frac{1}{1 - x} - \frac{1}{\color{blue}{-1} - x} \]
  3. Simplified74.6%

    \[\leadsto \color{blue}{\frac{1}{1 - x} - \frac{1}{-1 - x}} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. flip--53.5%

      \[\leadsto \frac{1}{\color{blue}{\frac{1 \cdot 1 - x \cdot x}{1 + x}}} - \frac{1}{-1 - x} \]
    2. metadata-eval53.5%

      \[\leadsto \frac{1}{\frac{\color{blue}{1} - x \cdot x}{1 + x}} - \frac{1}{-1 - x} \]
    3. metadata-eval53.5%

      \[\leadsto \frac{1}{\frac{\color{blue}{-1 \cdot -1} - x \cdot x}{1 + x}} - \frac{1}{-1 - x} \]
    4. associate-/r/53.4%

      \[\leadsto \color{blue}{\frac{1}{-1 \cdot -1 - x \cdot x} \cdot \left(1 + x\right)} - \frac{1}{-1 - x} \]
    5. metadata-eval53.4%

      \[\leadsto \frac{1}{\color{blue}{1} - x \cdot x} \cdot \left(1 + x\right) - \frac{1}{-1 - x} \]
    6. pow253.4%

      \[\leadsto \frac{1}{1 - \color{blue}{{x}^{2}}} \cdot \left(1 + x\right) - \frac{1}{-1 - x} \]
  6. Applied egg-rr53.4%

    \[\leadsto \color{blue}{\frac{1}{1 - {x}^{2}} \cdot \left(1 + x\right)} - \frac{1}{-1 - x} \]
  7. Step-by-step derivation
    1. associate-*l/53.6%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(1 + x\right)}{1 - {x}^{2}}} - \frac{1}{-1 - x} \]
    2. *-lft-identity53.6%

      \[\leadsto \frac{\color{blue}{1 + x}}{1 - {x}^{2}} - \frac{1}{-1 - x} \]
    3. +-commutative53.6%

      \[\leadsto \frac{\color{blue}{x + 1}}{1 - {x}^{2}} - \frac{1}{-1 - x} \]
  8. Simplified53.6%

    \[\leadsto \color{blue}{\frac{x + 1}{1 - {x}^{2}}} - \frac{1}{-1 - x} \]
  9. Step-by-step derivation
    1. clear-num53.5%

      \[\leadsto \color{blue}{\frac{1}{\frac{1 - {x}^{2}}{x + 1}}} - \frac{1}{-1 - x} \]
    2. metadata-eval53.5%

      \[\leadsto \frac{1}{\frac{\color{blue}{1 \cdot 1} - {x}^{2}}{x + 1}} - \frac{1}{-1 - x} \]
    3. unpow253.5%

      \[\leadsto \frac{1}{\frac{1 \cdot 1 - \color{blue}{x \cdot x}}{x + 1}} - \frac{1}{-1 - x} \]
    4. +-commutative53.5%

      \[\leadsto \frac{1}{\frac{1 \cdot 1 - x \cdot x}{\color{blue}{1 + x}}} - \frac{1}{-1 - x} \]
    5. flip--74.6%

      \[\leadsto \frac{1}{\color{blue}{1 - x}} - \frac{1}{-1 - x} \]
    6. frac-sub75.0%

      \[\leadsto \color{blue}{\frac{1 \cdot \left(-1 - x\right) - \left(1 - x\right) \cdot 1}{\left(1 - x\right) \cdot \left(-1 - x\right)}} \]
    7. *-commutative75.0%

      \[\leadsto \frac{1 \cdot \left(-1 - x\right) - \color{blue}{1 \cdot \left(1 - x\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    8. distribute-lft-out--75.0%

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\left(-1 - x\right) - \left(1 - x\right)\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    9. associate--r+78.4%

      \[\leadsto \frac{1 \cdot \color{blue}{\left(-1 - \left(x + \left(1 - x\right)\right)\right)}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    10. flip--28.4%

      \[\leadsto \frac{1 \cdot \color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{-1 + \left(x + \left(1 - x\right)\right)}}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    11. *-un-lft-identity28.4%

      \[\leadsto \frac{\color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{-1 + \left(x + \left(1 - x\right)\right)}}}{\left(1 - x\right) \cdot \left(-1 - x\right)} \]
    12. associate-/l/28.4%

      \[\leadsto \color{blue}{\frac{-1 \cdot -1 - \left(x + \left(1 - x\right)\right) \cdot \left(x + \left(1 - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(x + \left(1 - x\right)\right)\right)}} \]
  10. Applied egg-rr0.0%

    \[\leadsto \color{blue}{\frac{1 - {\left(1 + \left(x - x\right)\right)}^{2}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)}} \]
  11. Step-by-step derivation
    1. div-sub0.0%

      \[\leadsto \color{blue}{\frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{{\left(1 + \left(x - x\right)\right)}^{2}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)}} \]
    2. unpow20.0%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{\color{blue}{\left(1 + \left(x - x\right)\right) \cdot \left(1 + \left(x - x\right)\right)}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
    3. +-inverses0.0%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{\left(1 + \color{blue}{0}\right) \cdot \left(1 + \left(x - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
    4. metadata-eval0.0%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{\color{blue}{1} \cdot \left(1 + \left(x - x\right)\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
    5. +-inverses0.0%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{1 \cdot \left(1 + \color{blue}{0}\right)}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
    6. metadata-eval0.0%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{1 \cdot \color{blue}{1}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
    7. metadata-eval0.0%

      \[\leadsto \frac{1}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} - \frac{\color{blue}{1}}{\left(\left(1 - x\right) \cdot \left(-1 - x\right)\right) \cdot \left(-1 + \left(1 + \left(x - x\right)\right)\right)} \]
    8. +-inverses25.7%

      \[\leadsto \color{blue}{0} \]
  12. Simplified25.7%

    \[\leadsto \color{blue}{0} \]
  13. Final simplification25.7%

    \[\leadsto 0 \]
  14. Add Preprocessing

Reproduce

?
herbie shell --seed 2024074 
(FPCore (x)
  :name "Asymptote A"
  :precision binary64
  (- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))