Data.Colour.RGB:hslsv from colour-2.3.3, C

Percentage Accurate: 100.0% → 100.0%
Time: 5.1s
Alternatives: 8
Speedup: 1.0×

Specification

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

\\
\frac{x - y}{2 - \left(x + y\right)}
\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 8 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: 100.0% accurate, 1.0× speedup?

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

\\
\frac{x - y}{2 - \left(x + y\right)}
\end{array}

Alternative 1: 100.0% accurate, 1.0× speedup?

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

\\
\frac{x - y}{2 - \left(x + y\right)}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{x - y}{2 - \left(x + y\right)} \]
  2. Final simplification100.0%

    \[\leadsto \frac{x - y}{2 - \left(x + y\right)} \]

Alternative 2: 74.4% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{-x}{x + -2}\\ \mathbf{if}\;y \leq -5.8 \cdot 10^{-22}:\\ \;\;\;\;\frac{y}{y - 2}\\ \mathbf{elif}\;y \leq -1.9 \cdot 10^{-83}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq -1.05 \cdot 10^{-96}:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 2.3 \cdot 10^{-17}:\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{1 - \frac{2}{y}}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (/ (- x) (+ x -2.0))))
   (if (<= y -5.8e-22)
     (/ y (- y 2.0))
     (if (<= y -1.9e-83)
       t_0
       (if (<= y -1.05e-96)
         (* y -0.5)
         (if (<= y 2.3e-17) t_0 (/ 1.0 (- 1.0 (/ 2.0 y)))))))))
double code(double x, double y) {
	double t_0 = -x / (x + -2.0);
	double tmp;
	if (y <= -5.8e-22) {
		tmp = y / (y - 2.0);
	} else if (y <= -1.9e-83) {
		tmp = t_0;
	} else if (y <= -1.05e-96) {
		tmp = y * -0.5;
	} else if (y <= 2.3e-17) {
		tmp = t_0;
	} else {
		tmp = 1.0 / (1.0 - (2.0 / y));
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: t_0
    real(8) :: tmp
    t_0 = -x / (x + (-2.0d0))
    if (y <= (-5.8d-22)) then
        tmp = y / (y - 2.0d0)
    else if (y <= (-1.9d-83)) then
        tmp = t_0
    else if (y <= (-1.05d-96)) then
        tmp = y * (-0.5d0)
    else if (y <= 2.3d-17) then
        tmp = t_0
    else
        tmp = 1.0d0 / (1.0d0 - (2.0d0 / y))
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = -x / (x + -2.0);
	double tmp;
	if (y <= -5.8e-22) {
		tmp = y / (y - 2.0);
	} else if (y <= -1.9e-83) {
		tmp = t_0;
	} else if (y <= -1.05e-96) {
		tmp = y * -0.5;
	} else if (y <= 2.3e-17) {
		tmp = t_0;
	} else {
		tmp = 1.0 / (1.0 - (2.0 / y));
	}
	return tmp;
}
def code(x, y):
	t_0 = -x / (x + -2.0)
	tmp = 0
	if y <= -5.8e-22:
		tmp = y / (y - 2.0)
	elif y <= -1.9e-83:
		tmp = t_0
	elif y <= -1.05e-96:
		tmp = y * -0.5
	elif y <= 2.3e-17:
		tmp = t_0
	else:
		tmp = 1.0 / (1.0 - (2.0 / y))
	return tmp
function code(x, y)
	t_0 = Float64(Float64(-x) / Float64(x + -2.0))
	tmp = 0.0
	if (y <= -5.8e-22)
		tmp = Float64(y / Float64(y - 2.0));
	elseif (y <= -1.9e-83)
		tmp = t_0;
	elseif (y <= -1.05e-96)
		tmp = Float64(y * -0.5);
	elseif (y <= 2.3e-17)
		tmp = t_0;
	else
		tmp = Float64(1.0 / Float64(1.0 - Float64(2.0 / y)));
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = -x / (x + -2.0);
	tmp = 0.0;
	if (y <= -5.8e-22)
		tmp = y / (y - 2.0);
	elseif (y <= -1.9e-83)
		tmp = t_0;
	elseif (y <= -1.05e-96)
		tmp = y * -0.5;
	elseif (y <= 2.3e-17)
		tmp = t_0;
	else
		tmp = 1.0 / (1.0 - (2.0 / y));
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[((-x) / N[(x + -2.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -5.8e-22], N[(y / N[(y - 2.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[y, -1.9e-83], t$95$0, If[LessEqual[y, -1.05e-96], N[(y * -0.5), $MachinePrecision], If[LessEqual[y, 2.3e-17], t$95$0, N[(1.0 / N[(1.0 - N[(2.0 / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{-x}{x + -2}\\
\mathbf{if}\;y \leq -5.8 \cdot 10^{-22}:\\
\;\;\;\;\frac{y}{y - 2}\\

\mathbf{elif}\;y \leq -1.9 \cdot 10^{-83}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y \leq -1.05 \cdot 10^{-96}:\\
\;\;\;\;y \cdot -0.5\\

\mathbf{elif}\;y \leq 2.3 \cdot 10^{-17}:\\
\;\;\;\;t_0\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if y < -5.8000000000000003e-22

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around 0 84.0%

      \[\leadsto \color{blue}{\frac{y}{y - 2}} \]

    if -5.8000000000000003e-22 < y < -1.89999999999999988e-83 or -1.05000000000000001e-96 < y < 2.30000000000000009e-17

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in y around 0 85.6%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{x - 2}} \]
    5. Step-by-step derivation
      1. associate-*r/85.6%

        \[\leadsto \color{blue}{\frac{-1 \cdot x}{x - 2}} \]
      2. mul-1-neg85.6%

        \[\leadsto \frac{\color{blue}{-x}}{x - 2} \]
      3. sub-neg85.6%

        \[\leadsto \frac{-x}{\color{blue}{x + \left(-2\right)}} \]
      4. metadata-eval85.6%

        \[\leadsto \frac{-x}{x + \color{blue}{-2}} \]
    6. Simplified85.6%

      \[\leadsto \color{blue}{\frac{-x}{x + -2}} \]

    if -1.89999999999999988e-83 < y < -1.05000000000000001e-96

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around 0 100.0%

      \[\leadsto \color{blue}{\frac{y}{y - 2}} \]
    5. Taylor expanded in y around 0 100.0%

      \[\leadsto \color{blue}{-0.5 \cdot y} \]
    6. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto \color{blue}{y \cdot -0.5} \]
    7. Simplified100.0%

      \[\leadsto \color{blue}{y \cdot -0.5} \]

    if 2.30000000000000009e-17 < y

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around 0 81.7%

      \[\leadsto \color{blue}{\frac{y}{y - 2}} \]
    5. Step-by-step derivation
      1. clear-num81.7%

        \[\leadsto \color{blue}{\frac{1}{\frac{y - 2}{y}}} \]
      2. inv-pow81.7%

        \[\leadsto \color{blue}{{\left(\frac{y - 2}{y}\right)}^{-1}} \]
      3. sub-neg81.7%

        \[\leadsto {\left(\frac{\color{blue}{y + \left(-2\right)}}{y}\right)}^{-1} \]
      4. metadata-eval81.7%

        \[\leadsto {\left(\frac{y + \color{blue}{-2}}{y}\right)}^{-1} \]
    6. Applied egg-rr81.7%

      \[\leadsto \color{blue}{{\left(\frac{y + -2}{y}\right)}^{-1}} \]
    7. Step-by-step derivation
      1. unpow-181.7%

        \[\leadsto \color{blue}{\frac{1}{\frac{y + -2}{y}}} \]
      2. metadata-eval81.7%

        \[\leadsto \frac{1}{\frac{y + \color{blue}{\left(-2\right)}}{y}} \]
      3. sub-neg81.7%

        \[\leadsto \frac{1}{\frac{\color{blue}{y - 2}}{y}} \]
      4. div-sub81.7%

        \[\leadsto \frac{1}{\color{blue}{\frac{y}{y} - \frac{2}{y}}} \]
      5. *-inverses81.7%

        \[\leadsto \frac{1}{\color{blue}{1} - \frac{2}{y}} \]
    8. Simplified81.7%

      \[\leadsto \color{blue}{\frac{1}{1 - \frac{2}{y}}} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification84.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -5.8 \cdot 10^{-22}:\\ \;\;\;\;\frac{y}{y - 2}\\ \mathbf{elif}\;y \leq -1.9 \cdot 10^{-83}:\\ \;\;\;\;\frac{-x}{x + -2}\\ \mathbf{elif}\;y \leq -1.05 \cdot 10^{-96}:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 2.3 \cdot 10^{-17}:\\ \;\;\;\;\frac{-x}{x + -2}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{1 - \frac{2}{y}}\\ \end{array} \]

Alternative 3: 74.4% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y}{y - 2}\\ t_1 := \frac{-x}{x + -2}\\ \mathbf{if}\;y \leq -1.1 \cdot 10^{-20}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq -2.4 \cdot 10^{-83}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;y \leq -2.7 \cdot 10^{-96}:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 1.55 \cdot 10^{-17}:\\ \;\;\;\;t_1\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (/ y (- y 2.0))) (t_1 (/ (- x) (+ x -2.0))))
   (if (<= y -1.1e-20)
     t_0
     (if (<= y -2.4e-83)
       t_1
       (if (<= y -2.7e-96) (* y -0.5) (if (<= y 1.55e-17) t_1 t_0))))))
double code(double x, double y) {
	double t_0 = y / (y - 2.0);
	double t_1 = -x / (x + -2.0);
	double tmp;
	if (y <= -1.1e-20) {
		tmp = t_0;
	} else if (y <= -2.4e-83) {
		tmp = t_1;
	} else if (y <= -2.7e-96) {
		tmp = y * -0.5;
	} else if (y <= 1.55e-17) {
		tmp = t_1;
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = y / (y - 2.0d0)
    t_1 = -x / (x + (-2.0d0))
    if (y <= (-1.1d-20)) then
        tmp = t_0
    else if (y <= (-2.4d-83)) then
        tmp = t_1
    else if (y <= (-2.7d-96)) then
        tmp = y * (-0.5d0)
    else if (y <= 1.55d-17) then
        tmp = t_1
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = y / (y - 2.0);
	double t_1 = -x / (x + -2.0);
	double tmp;
	if (y <= -1.1e-20) {
		tmp = t_0;
	} else if (y <= -2.4e-83) {
		tmp = t_1;
	} else if (y <= -2.7e-96) {
		tmp = y * -0.5;
	} else if (y <= 1.55e-17) {
		tmp = t_1;
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = y / (y - 2.0)
	t_1 = -x / (x + -2.0)
	tmp = 0
	if y <= -1.1e-20:
		tmp = t_0
	elif y <= -2.4e-83:
		tmp = t_1
	elif y <= -2.7e-96:
		tmp = y * -0.5
	elif y <= 1.55e-17:
		tmp = t_1
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(y / Float64(y - 2.0))
	t_1 = Float64(Float64(-x) / Float64(x + -2.0))
	tmp = 0.0
	if (y <= -1.1e-20)
		tmp = t_0;
	elseif (y <= -2.4e-83)
		tmp = t_1;
	elseif (y <= -2.7e-96)
		tmp = Float64(y * -0.5);
	elseif (y <= 1.55e-17)
		tmp = t_1;
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = y / (y - 2.0);
	t_1 = -x / (x + -2.0);
	tmp = 0.0;
	if (y <= -1.1e-20)
		tmp = t_0;
	elseif (y <= -2.4e-83)
		tmp = t_1;
	elseif (y <= -2.7e-96)
		tmp = y * -0.5;
	elseif (y <= 1.55e-17)
		tmp = t_1;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(y / N[(y - 2.0), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[((-x) / N[(x + -2.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -1.1e-20], t$95$0, If[LessEqual[y, -2.4e-83], t$95$1, If[LessEqual[y, -2.7e-96], N[(y * -0.5), $MachinePrecision], If[LessEqual[y, 1.55e-17], t$95$1, t$95$0]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{y}{y - 2}\\
t_1 := \frac{-x}{x + -2}\\
\mathbf{if}\;y \leq -1.1 \cdot 10^{-20}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y \leq -2.4 \cdot 10^{-83}:\\
\;\;\;\;t_1\\

\mathbf{elif}\;y \leq -2.7 \cdot 10^{-96}:\\
\;\;\;\;y \cdot -0.5\\

\mathbf{elif}\;y \leq 1.55 \cdot 10^{-17}:\\
\;\;\;\;t_1\\

\mathbf{else}:\\
\;\;\;\;t_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -1.09999999999999995e-20 or 1.5499999999999999e-17 < y

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around 0 83.0%

      \[\leadsto \color{blue}{\frac{y}{y - 2}} \]

    if -1.09999999999999995e-20 < y < -2.4000000000000001e-83 or -2.7e-96 < y < 1.5499999999999999e-17

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in y around 0 85.6%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{x - 2}} \]
    5. Step-by-step derivation
      1. associate-*r/85.6%

        \[\leadsto \color{blue}{\frac{-1 \cdot x}{x - 2}} \]
      2. mul-1-neg85.6%

        \[\leadsto \frac{\color{blue}{-x}}{x - 2} \]
      3. sub-neg85.6%

        \[\leadsto \frac{-x}{\color{blue}{x + \left(-2\right)}} \]
      4. metadata-eval85.6%

        \[\leadsto \frac{-x}{x + \color{blue}{-2}} \]
    6. Simplified85.6%

      \[\leadsto \color{blue}{\frac{-x}{x + -2}} \]

    if -2.4000000000000001e-83 < y < -2.7e-96

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around 0 100.0%

      \[\leadsto \color{blue}{\frac{y}{y - 2}} \]
    5. Taylor expanded in y around 0 100.0%

      \[\leadsto \color{blue}{-0.5 \cdot y} \]
    6. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto \color{blue}{y \cdot -0.5} \]
    7. Simplified100.0%

      \[\leadsto \color{blue}{y \cdot -0.5} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification84.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.1 \cdot 10^{-20}:\\ \;\;\;\;\frac{y}{y - 2}\\ \mathbf{elif}\;y \leq -2.4 \cdot 10^{-83}:\\ \;\;\;\;\frac{-x}{x + -2}\\ \mathbf{elif}\;y \leq -2.7 \cdot 10^{-96}:\\ \;\;\;\;y \cdot -0.5\\ \mathbf{elif}\;y \leq 1.55 \cdot 10^{-17}:\\ \;\;\;\;\frac{-x}{x + -2}\\ \mathbf{else}:\\ \;\;\;\;\frac{y}{y - 2}\\ \end{array} \]

Alternative 4: 75.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -5.5 \cdot 10^{+29} \lor \neg \left(x \leq 8.5 \cdot 10^{+30}\right):\\ \;\;\;\;\frac{y - x}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{y}{y - 2}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (or (<= x -5.5e+29) (not (<= x 8.5e+30))) (/ (- y x) x) (/ y (- y 2.0))))
double code(double x, double y) {
	double tmp;
	if ((x <= -5.5e+29) || !(x <= 8.5e+30)) {
		tmp = (y - x) / x;
	} else {
		tmp = y / (y - 2.0);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if ((x <= (-5.5d+29)) .or. (.not. (x <= 8.5d+30))) then
        tmp = (y - x) / x
    else
        tmp = y / (y - 2.0d0)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if ((x <= -5.5e+29) || !(x <= 8.5e+30)) {
		tmp = (y - x) / x;
	} else {
		tmp = y / (y - 2.0);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if (x <= -5.5e+29) or not (x <= 8.5e+30):
		tmp = (y - x) / x
	else:
		tmp = y / (y - 2.0)
	return tmp
function code(x, y)
	tmp = 0.0
	if ((x <= -5.5e+29) || !(x <= 8.5e+30))
		tmp = Float64(Float64(y - x) / x);
	else
		tmp = Float64(y / Float64(y - 2.0));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if ((x <= -5.5e+29) || ~((x <= 8.5e+30)))
		tmp = (y - x) / x;
	else
		tmp = y / (y - 2.0);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[Or[LessEqual[x, -5.5e+29], N[Not[LessEqual[x, 8.5e+30]], $MachinePrecision]], N[(N[(y - x), $MachinePrecision] / x), $MachinePrecision], N[(y / N[(y - 2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -5.5 \cdot 10^{+29} \lor \neg \left(x \leq 8.5 \cdot 10^{+30}\right):\\
\;\;\;\;\frac{y - x}{x}\\

\mathbf{else}:\\
\;\;\;\;\frac{y}{y - 2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -5.5e29 or 8.4999999999999995e30 < x

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Step-by-step derivation
      1. clear-num100.0%

        \[\leadsto \color{blue}{\frac{1}{\frac{x + \left(y + -2\right)}{y - x}}} \]
      2. associate-/r/99.7%

        \[\leadsto \color{blue}{\frac{1}{x + \left(y + -2\right)} \cdot \left(y - x\right)} \]
      3. +-commutative99.7%

        \[\leadsto \frac{1}{\color{blue}{\left(y + -2\right) + x}} \cdot \left(y - x\right) \]
      4. associate-+l+99.7%

        \[\leadsto \frac{1}{\color{blue}{y + \left(-2 + x\right)}} \cdot \left(y - x\right) \]
    5. Applied egg-rr99.7%

      \[\leadsto \color{blue}{\frac{1}{y + \left(-2 + x\right)} \cdot \left(y - x\right)} \]
    6. Taylor expanded in x around inf 81.6%

      \[\leadsto \color{blue}{\frac{1}{x}} \cdot \left(y - x\right) \]
    7. Step-by-step derivation
      1. associate-*l/81.8%

        \[\leadsto \color{blue}{\frac{1 \cdot \left(y - x\right)}{x}} \]
      2. *-un-lft-identity81.8%

        \[\leadsto \frac{\color{blue}{y - x}}{x} \]
    8. Applied egg-rr81.8%

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

    if -5.5e29 < x < 8.4999999999999995e30

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around 0 80.2%

      \[\leadsto \color{blue}{\frac{y}{y - 2}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -5.5 \cdot 10^{+29} \lor \neg \left(x \leq 8.5 \cdot 10^{+30}\right):\\ \;\;\;\;\frac{y - x}{x}\\ \mathbf{else}:\\ \;\;\;\;\frac{y}{y - 2}\\ \end{array} \]

Alternative 5: 63.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -5 \cdot 10^{+30}:\\ \;\;\;\;-1\\ \mathbf{elif}\;x \leq 500000000:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;-1 - \frac{2}{x}\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= x -5e+30) -1.0 (if (<= x 500000000.0) 1.0 (- -1.0 (/ 2.0 x)))))
double code(double x, double y) {
	double tmp;
	if (x <= -5e+30) {
		tmp = -1.0;
	} else if (x <= 500000000.0) {
		tmp = 1.0;
	} else {
		tmp = -1.0 - (2.0 / x);
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (x <= (-5d+30)) then
        tmp = -1.0d0
    else if (x <= 500000000.0d0) then
        tmp = 1.0d0
    else
        tmp = (-1.0d0) - (2.0d0 / x)
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (x <= -5e+30) {
		tmp = -1.0;
	} else if (x <= 500000000.0) {
		tmp = 1.0;
	} else {
		tmp = -1.0 - (2.0 / x);
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if x <= -5e+30:
		tmp = -1.0
	elif x <= 500000000.0:
		tmp = 1.0
	else:
		tmp = -1.0 - (2.0 / x)
	return tmp
function code(x, y)
	tmp = 0.0
	if (x <= -5e+30)
		tmp = -1.0;
	elseif (x <= 500000000.0)
		tmp = 1.0;
	else
		tmp = Float64(-1.0 - Float64(2.0 / x));
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (x <= -5e+30)
		tmp = -1.0;
	elseif (x <= 500000000.0)
		tmp = 1.0;
	else
		tmp = -1.0 - (2.0 / x);
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[x, -5e+30], -1.0, If[LessEqual[x, 500000000.0], 1.0, N[(-1.0 - N[(2.0 / x), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -5 \cdot 10^{+30}:\\
\;\;\;\;-1\\

\mathbf{elif}\;x \leq 500000000:\\
\;\;\;\;1\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < -4.9999999999999998e30

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around inf 75.2%

      \[\leadsto \color{blue}{-1} \]

    if -4.9999999999999998e30 < x < 5e8

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in y around inf 63.3%

      \[\leadsto \color{blue}{1} \]

    if 5e8 < x

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in y around 0 82.8%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{x - 2}} \]
    5. Step-by-step derivation
      1. associate-*r/82.8%

        \[\leadsto \color{blue}{\frac{-1 \cdot x}{x - 2}} \]
      2. mul-1-neg82.8%

        \[\leadsto \frac{\color{blue}{-x}}{x - 2} \]
      3. sub-neg82.8%

        \[\leadsto \frac{-x}{\color{blue}{x + \left(-2\right)}} \]
      4. metadata-eval82.8%

        \[\leadsto \frac{-x}{x + \color{blue}{-2}} \]
    6. Simplified82.8%

      \[\leadsto \color{blue}{\frac{-x}{x + -2}} \]
    7. Taylor expanded in x around inf 82.8%

      \[\leadsto \color{blue}{-\left(1 + 2 \cdot \frac{1}{x}\right)} \]
    8. Step-by-step derivation
      1. distribute-neg-in82.8%

        \[\leadsto \color{blue}{\left(-1\right) + \left(-2 \cdot \frac{1}{x}\right)} \]
      2. metadata-eval82.8%

        \[\leadsto \color{blue}{-1} + \left(-2 \cdot \frac{1}{x}\right) \]
      3. unsub-neg82.8%

        \[\leadsto \color{blue}{-1 - 2 \cdot \frac{1}{x}} \]
      4. associate-*r/82.8%

        \[\leadsto -1 - \color{blue}{\frac{2 \cdot 1}{x}} \]
      5. metadata-eval82.8%

        \[\leadsto -1 - \frac{\color{blue}{2}}{x} \]
    9. Simplified82.8%

      \[\leadsto \color{blue}{-1 - \frac{2}{x}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification70.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -5 \cdot 10^{+30}:\\ \;\;\;\;-1\\ \mathbf{elif}\;x \leq 500000000:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;-1 - \frac{2}{x}\\ \end{array} \]

Alternative 6: 74.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -2.3 \cdot 10^{+30}:\\ \;\;\;\;-1\\ \mathbf{elif}\;x \leq 6.2 \cdot 10^{+38}:\\ \;\;\;\;\frac{y}{y - 2}\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= x -2.3e+30) -1.0 (if (<= x 6.2e+38) (/ y (- y 2.0)) -1.0)))
double code(double x, double y) {
	double tmp;
	if (x <= -2.3e+30) {
		tmp = -1.0;
	} else if (x <= 6.2e+38) {
		tmp = y / (y - 2.0);
	} else {
		tmp = -1.0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (x <= (-2.3d+30)) then
        tmp = -1.0d0
    else if (x <= 6.2d+38) then
        tmp = y / (y - 2.0d0)
    else
        tmp = -1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (x <= -2.3e+30) {
		tmp = -1.0;
	} else if (x <= 6.2e+38) {
		tmp = y / (y - 2.0);
	} else {
		tmp = -1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if x <= -2.3e+30:
		tmp = -1.0
	elif x <= 6.2e+38:
		tmp = y / (y - 2.0)
	else:
		tmp = -1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if (x <= -2.3e+30)
		tmp = -1.0;
	elseif (x <= 6.2e+38)
		tmp = Float64(y / Float64(y - 2.0));
	else
		tmp = -1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (x <= -2.3e+30)
		tmp = -1.0;
	elseif (x <= 6.2e+38)
		tmp = y / (y - 2.0);
	else
		tmp = -1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[x, -2.3e+30], -1.0, If[LessEqual[x, 6.2e+38], N[(y / N[(y - 2.0), $MachinePrecision]), $MachinePrecision], -1.0]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -2.3 \cdot 10^{+30}:\\
\;\;\;\;-1\\

\mathbf{elif}\;x \leq 6.2 \cdot 10^{+38}:\\
\;\;\;\;\frac{y}{y - 2}\\

\mathbf{else}:\\
\;\;\;\;-1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -2.3e30 or 6.20000000000000035e38 < x

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around inf 81.2%

      \[\leadsto \color{blue}{-1} \]

    if -2.3e30 < x < 6.20000000000000035e38

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around 0 80.2%

      \[\leadsto \color{blue}{\frac{y}{y - 2}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -2.3 \cdot 10^{+30}:\\ \;\;\;\;-1\\ \mathbf{elif}\;x \leq 6.2 \cdot 10^{+38}:\\ \;\;\;\;\frac{y}{y - 2}\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \]

Alternative 7: 63.5% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -4.1 \cdot 10^{+30}:\\ \;\;\;\;-1\\ \mathbf{elif}\;x \leq 5.8 \cdot 10^{+16}:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= x -4.1e+30) -1.0 (if (<= x 5.8e+16) 1.0 -1.0)))
double code(double x, double y) {
	double tmp;
	if (x <= -4.1e+30) {
		tmp = -1.0;
	} else if (x <= 5.8e+16) {
		tmp = 1.0;
	} else {
		tmp = -1.0;
	}
	return tmp;
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: tmp
    if (x <= (-4.1d+30)) then
        tmp = -1.0d0
    else if (x <= 5.8d+16) then
        tmp = 1.0d0
    else
        tmp = -1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (x <= -4.1e+30) {
		tmp = -1.0;
	} else if (x <= 5.8e+16) {
		tmp = 1.0;
	} else {
		tmp = -1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if x <= -4.1e+30:
		tmp = -1.0
	elif x <= 5.8e+16:
		tmp = 1.0
	else:
		tmp = -1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if (x <= -4.1e+30)
		tmp = -1.0;
	elseif (x <= 5.8e+16)
		tmp = 1.0;
	else
		tmp = -1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (x <= -4.1e+30)
		tmp = -1.0;
	elseif (x <= 5.8e+16)
		tmp = 1.0;
	else
		tmp = -1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[x, -4.1e+30], -1.0, If[LessEqual[x, 5.8e+16], 1.0, -1.0]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -4.1 \cdot 10^{+30}:\\
\;\;\;\;-1\\

\mathbf{elif}\;x \leq 5.8 \cdot 10^{+16}:\\
\;\;\;\;1\\

\mathbf{else}:\\
\;\;\;\;-1\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -4.10000000000000005e30 or 5.8e16 < x

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in x around inf 80.0%

      \[\leadsto \color{blue}{-1} \]

    if -4.10000000000000005e30 < x < 5.8e16

    1. Initial program 100.0%

      \[\frac{x - y}{2 - \left(x + y\right)} \]
    2. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
      2. remove-double-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
      3. unsub-neg100.0%

        \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
      4. distribute-neg-in100.0%

        \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      5. neg-mul-1100.0%

        \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
      6. *-commutative100.0%

        \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
      7. associate-/l*100.0%

        \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
      8. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
      9. sub-neg100.0%

        \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
      10. div-sub100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
      11. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
      12. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
      13. sub-neg100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
      14. distribute-frac-neg100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
      15. neg-mul-1100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
      16. *-commutative100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
      17. associate-/l*100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
      18. metadata-eval100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
      19. /-rgt-identity100.0%

        \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
      20. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
      21. +-commutative100.0%

        \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
      22. associate-+r+100.0%

        \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
      23. metadata-eval100.0%

        \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
    4. Taylor expanded in y around inf 63.1%

      \[\leadsto \color{blue}{1} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification70.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -4.1 \cdot 10^{+30}:\\ \;\;\;\;-1\\ \mathbf{elif}\;x \leq 5.8 \cdot 10^{+16}:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;-1\\ \end{array} \]

Alternative 8: 38.3% accurate, 9.0× speedup?

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

\\
-1
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{x - y}{2 - \left(x + y\right)} \]
  2. Step-by-step derivation
    1. +-commutative100.0%

      \[\leadsto \frac{x - y}{2 - \color{blue}{\left(y + x\right)}} \]
    2. remove-double-neg100.0%

      \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right)} - y}{2 - \left(y + x\right)} \]
    3. unsub-neg100.0%

      \[\leadsto \frac{\color{blue}{\left(-\left(-x\right)\right) + \left(-y\right)}}{2 - \left(y + x\right)} \]
    4. distribute-neg-in100.0%

      \[\leadsto \frac{\color{blue}{-\left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
    5. neg-mul-1100.0%

      \[\leadsto \frac{\color{blue}{-1 \cdot \left(\left(-x\right) + y\right)}}{2 - \left(y + x\right)} \]
    6. *-commutative100.0%

      \[\leadsto \frac{\color{blue}{\left(\left(-x\right) + y\right) \cdot -1}}{2 - \left(y + x\right)} \]
    7. associate-/l*100.0%

      \[\leadsto \color{blue}{\frac{\left(-x\right) + y}{\frac{2 - \left(y + x\right)}{-1}}} \]
    8. +-commutative100.0%

      \[\leadsto \frac{\color{blue}{y + \left(-x\right)}}{\frac{2 - \left(y + x\right)}{-1}} \]
    9. sub-neg100.0%

      \[\leadsto \frac{\color{blue}{y - x}}{\frac{2 - \left(y + x\right)}{-1}} \]
    10. div-sub100.0%

      \[\leadsto \frac{y - x}{\color{blue}{\frac{2}{-1} - \frac{y + x}{-1}}} \]
    11. metadata-eval100.0%

      \[\leadsto \frac{y - x}{\color{blue}{-2} - \frac{y + x}{-1}} \]
    12. metadata-eval100.0%

      \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right)} - \frac{y + x}{-1}} \]
    13. sub-neg100.0%

      \[\leadsto \frac{y - x}{\color{blue}{\left(-2\right) + \left(-\frac{y + x}{-1}\right)}} \]
    14. distribute-frac-neg100.0%

      \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{-\left(y + x\right)}{-1}}} \]
    15. neg-mul-1100.0%

      \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{-1 \cdot \left(y + x\right)}}{-1}} \]
    16. *-commutative100.0%

      \[\leadsto \frac{y - x}{\left(-2\right) + \frac{\color{blue}{\left(y + x\right) \cdot -1}}{-1}} \]
    17. associate-/l*100.0%

      \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\frac{y + x}{\frac{-1}{-1}}}} \]
    18. metadata-eval100.0%

      \[\leadsto \frac{y - x}{\left(-2\right) + \frac{y + x}{\color{blue}{1}}} \]
    19. /-rgt-identity100.0%

      \[\leadsto \frac{y - x}{\left(-2\right) + \color{blue}{\left(y + x\right)}} \]
    20. +-commutative100.0%

      \[\leadsto \frac{y - x}{\color{blue}{\left(y + x\right) + \left(-2\right)}} \]
    21. +-commutative100.0%

      \[\leadsto \frac{y - x}{\color{blue}{\left(x + y\right)} + \left(-2\right)} \]
    22. associate-+r+100.0%

      \[\leadsto \frac{y - x}{\color{blue}{x + \left(y + \left(-2\right)\right)}} \]
    23. metadata-eval100.0%

      \[\leadsto \frac{y - x}{x + \left(y + \color{blue}{-2}\right)} \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{y - x}{x + \left(y + -2\right)}} \]
  4. Taylor expanded in x around inf 36.5%

    \[\leadsto \color{blue}{-1} \]
  5. Final simplification36.5%

    \[\leadsto -1 \]

Developer target: 100.0% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 2 - \left(x + y\right)\\ \frac{x}{t_0} - \frac{y}{t_0} \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (- 2.0 (+ x y)))) (- (/ x t_0) (/ y t_0))))
double code(double x, double y) {
	double t_0 = 2.0 - (x + y);
	return (x / t_0) - (y / t_0);
}
real(8) function code(x, y)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8) :: t_0
    t_0 = 2.0d0 - (x + y)
    code = (x / t_0) - (y / t_0)
end function
public static double code(double x, double y) {
	double t_0 = 2.0 - (x + y);
	return (x / t_0) - (y / t_0);
}
def code(x, y):
	t_0 = 2.0 - (x + y)
	return (x / t_0) - (y / t_0)
function code(x, y)
	t_0 = Float64(2.0 - Float64(x + y))
	return Float64(Float64(x / t_0) - Float64(y / t_0))
end
function tmp = code(x, y)
	t_0 = 2.0 - (x + y);
	tmp = (x / t_0) - (y / t_0);
end
code[x_, y_] := Block[{t$95$0 = N[(2.0 - N[(x + y), $MachinePrecision]), $MachinePrecision]}, N[(N[(x / t$95$0), $MachinePrecision] - N[(y / t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 2 - \left(x + y\right)\\
\frac{x}{t_0} - \frac{y}{t_0}
\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2023306 
(FPCore (x y)
  :name "Data.Colour.RGB:hslsv from colour-2.3.3, C"
  :precision binary64

  :herbie-target
  (- (/ x (- 2.0 (+ x y))) (/ y (- 2.0 (+ x y))))

  (/ (- x y) (- 2.0 (+ x y))))