Diagrams.Trail:splitAtParam from diagrams-lib-1.3.0.3, C

Percentage Accurate: 100.0% → 100.0%
Time: 4.2s
Alternatives: 7
Speedup: 1.0×

Specification

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

\\
\frac{x - y}{1 - y}
\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 7 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?

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

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

Alternative 1: 100.0% accurate, 1.0× speedup?

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

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

    \[\frac{x - y}{1 - y} \]
  2. Final simplification100.0%

    \[\leadsto \frac{x - y}{1 - y} \]

Alternative 2: 86.4% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \frac{1 - x}{y}\\ t_1 := \frac{x}{1 - y}\\ \mathbf{if}\;y \leq -1400000:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 6.1 \cdot 10^{-118}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;y \leq 3.2 \cdot 10^{-100}:\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{elif}\;y \leq 360000000:\\ \;\;\;\;t_1\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 1.0 (/ (- 1.0 x) y))) (t_1 (/ x (- 1.0 y))))
   (if (<= y -1400000.0)
     t_0
     (if (<= y 6.1e-118)
       t_1
       (if (<= y 3.2e-100)
         (/ y (+ y -1.0))
         (if (<= y 360000000.0) t_1 t_0))))))
double code(double x, double y) {
	double t_0 = 1.0 + ((1.0 - x) / y);
	double t_1 = x / (1.0 - y);
	double tmp;
	if (y <= -1400000.0) {
		tmp = t_0;
	} else if (y <= 6.1e-118) {
		tmp = t_1;
	} else if (y <= 3.2e-100) {
		tmp = y / (y + -1.0);
	} else if (y <= 360000000.0) {
		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 = 1.0d0 + ((1.0d0 - x) / y)
    t_1 = x / (1.0d0 - y)
    if (y <= (-1400000.0d0)) then
        tmp = t_0
    else if (y <= 6.1d-118) then
        tmp = t_1
    else if (y <= 3.2d-100) then
        tmp = y / (y + (-1.0d0))
    else if (y <= 360000000.0d0) 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 = 1.0 + ((1.0 - x) / y);
	double t_1 = x / (1.0 - y);
	double tmp;
	if (y <= -1400000.0) {
		tmp = t_0;
	} else if (y <= 6.1e-118) {
		tmp = t_1;
	} else if (y <= 3.2e-100) {
		tmp = y / (y + -1.0);
	} else if (y <= 360000000.0) {
		tmp = t_1;
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 + ((1.0 - x) / y)
	t_1 = x / (1.0 - y)
	tmp = 0
	if y <= -1400000.0:
		tmp = t_0
	elif y <= 6.1e-118:
		tmp = t_1
	elif y <= 3.2e-100:
		tmp = y / (y + -1.0)
	elif y <= 360000000.0:
		tmp = t_1
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 + Float64(Float64(1.0 - x) / y))
	t_1 = Float64(x / Float64(1.0 - y))
	tmp = 0.0
	if (y <= -1400000.0)
		tmp = t_0;
	elseif (y <= 6.1e-118)
		tmp = t_1;
	elseif (y <= 3.2e-100)
		tmp = Float64(y / Float64(y + -1.0));
	elseif (y <= 360000000.0)
		tmp = t_1;
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = 1.0 + ((1.0 - x) / y);
	t_1 = x / (1.0 - y);
	tmp = 0.0;
	if (y <= -1400000.0)
		tmp = t_0;
	elseif (y <= 6.1e-118)
		tmp = t_1;
	elseif (y <= 3.2e-100)
		tmp = y / (y + -1.0);
	elseif (y <= 360000000.0)
		tmp = t_1;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[(N[(1.0 - x), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(x / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -1400000.0], t$95$0, If[LessEqual[y, 6.1e-118], t$95$1, If[LessEqual[y, 3.2e-100], N[(y / N[(y + -1.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 360000000.0], t$95$1, t$95$0]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \frac{1 - x}{y}\\
t_1 := \frac{x}{1 - y}\\
\mathbf{if}\;y \leq -1400000:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y \leq 6.1 \cdot 10^{-118}:\\
\;\;\;\;t_1\\

\mathbf{elif}\;y \leq 3.2 \cdot 10^{-100}:\\
\;\;\;\;\frac{y}{y + -1}\\

\mathbf{elif}\;y \leq 360000000:\\
\;\;\;\;t_1\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -1.4e6 or 3.6e8 < y

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 99.9%

      \[\leadsto \color{blue}{\frac{1}{y} + \left(1 + -1 \cdot \frac{x}{y}\right)} \]
    5. Step-by-step derivation
      1. +-commutative99.9%

        \[\leadsto \frac{1}{y} + \color{blue}{\left(-1 \cdot \frac{x}{y} + 1\right)} \]
      2. associate-+r+99.9%

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

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

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

        \[\leadsto \color{blue}{\frac{1 - x}{y}} + 1 \]
      6. unsub-neg99.9%

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

        \[\leadsto \frac{1 + \color{blue}{-1 \cdot x}}{y} + 1 \]
      8. +-commutative99.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot x + 1}}{y} + 1 \]
      9. metadata-eval99.9%

        \[\leadsto \frac{-1 \cdot x + \color{blue}{-1 \cdot -1}}{y} + 1 \]
      10. distribute-lft-in99.9%

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

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

        \[\leadsto \frac{-1 \cdot \color{blue}{\left(x - 1\right)}}{y} + 1 \]
      13. associate-*r/99.9%

        \[\leadsto \color{blue}{-1 \cdot \frac{x - 1}{y}} + 1 \]
      14. +-commutative99.9%

        \[\leadsto \color{blue}{1 + -1 \cdot \frac{x - 1}{y}} \]
      15. associate-*r/99.9%

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

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

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

        \[\leadsto 1 + \frac{\color{blue}{-1 \cdot x + -1 \cdot -1}}{y} \]
      19. metadata-eval99.9%

        \[\leadsto 1 + \frac{-1 \cdot x + \color{blue}{1}}{y} \]
      20. +-commutative99.9%

        \[\leadsto 1 + \frac{\color{blue}{1 + -1 \cdot x}}{y} \]
      21. mul-1-neg99.9%

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

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

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

    if -1.4e6 < y < 6.09999999999999985e-118 or 3.20000000000000017e-100 < y < 3.6e8

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 80.7%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg80.7%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval80.7%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-180.7%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac80.7%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative80.7%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified80.7%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg80.7%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. div-inv80.7%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(-1 + y\right)}} \]
      3. remove-double-neg80.7%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(-1 + y\right)} \]
      4. +-commutative80.7%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + -1\right)}} \]
      5. distribute-neg-in80.7%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      6. neg-mul-180.7%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      7. *-commutative80.7%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      8. metadata-eval80.7%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      9. fma-def80.7%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr80.7%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/80.7%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity80.7%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef80.7%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. +-commutative80.7%

        \[\leadsto \frac{x}{\color{blue}{1 + y \cdot -1}} \]
      5. *-commutative80.7%

        \[\leadsto \frac{x}{1 + \color{blue}{-1 \cdot y}} \]
      6. neg-mul-180.7%

        \[\leadsto \frac{x}{1 + \color{blue}{\left(-y\right)}} \]
      7. unsub-neg80.7%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified80.7%

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

    if 6.09999999999999985e-118 < y < 3.20000000000000017e-100

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around 0 100.0%

      \[\leadsto \color{blue}{\frac{y}{y - 1}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification90.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1400000:\\ \;\;\;\;1 + \frac{1 - x}{y}\\ \mathbf{elif}\;y \leq 6.1 \cdot 10^{-118}:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{elif}\;y \leq 3.2 \cdot 10^{-100}:\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{elif}\;y \leq 360000000:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;1 + \frac{1 - x}{y}\\ \end{array} \]

Alternative 3: 74.6% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y}{y + -1}\\ \mathbf{if}\;y \leq -2.8 \cdot 10^{-35}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 6.1 \cdot 10^{-118}:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{elif}\;y \leq 3.6 \cdot 10^{-100} \lor \neg \left(y \leq 4.1 \cdot 10^{-17}\right):\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (/ y (+ y -1.0))))
   (if (<= y -2.8e-35)
     t_0
     (if (<= y 6.1e-118)
       (/ x (- 1.0 y))
       (if (or (<= y 3.6e-100) (not (<= y 4.1e-17))) t_0 x)))))
double code(double x, double y) {
	double t_0 = y / (y + -1.0);
	double tmp;
	if (y <= -2.8e-35) {
		tmp = t_0;
	} else if (y <= 6.1e-118) {
		tmp = x / (1.0 - y);
	} else if ((y <= 3.6e-100) || !(y <= 4.1e-17)) {
		tmp = t_0;
	} else {
		tmp = x;
	}
	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 = y / (y + (-1.0d0))
    if (y <= (-2.8d-35)) then
        tmp = t_0
    else if (y <= 6.1d-118) then
        tmp = x / (1.0d0 - y)
    else if ((y <= 3.6d-100) .or. (.not. (y <= 4.1d-17))) then
        tmp = t_0
    else
        tmp = x
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = y / (y + -1.0);
	double tmp;
	if (y <= -2.8e-35) {
		tmp = t_0;
	} else if (y <= 6.1e-118) {
		tmp = x / (1.0 - y);
	} else if ((y <= 3.6e-100) || !(y <= 4.1e-17)) {
		tmp = t_0;
	} else {
		tmp = x;
	}
	return tmp;
}
def code(x, y):
	t_0 = y / (y + -1.0)
	tmp = 0
	if y <= -2.8e-35:
		tmp = t_0
	elif y <= 6.1e-118:
		tmp = x / (1.0 - y)
	elif (y <= 3.6e-100) or not (y <= 4.1e-17):
		tmp = t_0
	else:
		tmp = x
	return tmp
function code(x, y)
	t_0 = Float64(y / Float64(y + -1.0))
	tmp = 0.0
	if (y <= -2.8e-35)
		tmp = t_0;
	elseif (y <= 6.1e-118)
		tmp = Float64(x / Float64(1.0 - y));
	elseif ((y <= 3.6e-100) || !(y <= 4.1e-17))
		tmp = t_0;
	else
		tmp = x;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = y / (y + -1.0);
	tmp = 0.0;
	if (y <= -2.8e-35)
		tmp = t_0;
	elseif (y <= 6.1e-118)
		tmp = x / (1.0 - y);
	elseif ((y <= 3.6e-100) || ~((y <= 4.1e-17)))
		tmp = t_0;
	else
		tmp = x;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(y / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -2.8e-35], t$95$0, If[LessEqual[y, 6.1e-118], N[(x / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], If[Or[LessEqual[y, 3.6e-100], N[Not[LessEqual[y, 4.1e-17]], $MachinePrecision]], t$95$0, x]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{y}{y + -1}\\
\mathbf{if}\;y \leq -2.8 \cdot 10^{-35}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y \leq 6.1 \cdot 10^{-118}:\\
\;\;\;\;\frac{x}{1 - y}\\

\mathbf{elif}\;y \leq 3.6 \cdot 10^{-100} \lor \neg \left(y \leq 4.1 \cdot 10^{-17}\right):\\
\;\;\;\;t_0\\

\mathbf{else}:\\
\;\;\;\;x\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -2.8e-35 or 6.09999999999999985e-118 < y < 3.5999999999999999e-100 or 4.1000000000000001e-17 < y

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around 0 78.9%

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

    if -2.8e-35 < y < 6.09999999999999985e-118

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 85.5%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg85.5%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval85.5%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-185.5%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac85.5%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative85.5%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified85.5%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg85.5%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. div-inv85.5%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(-1 + y\right)}} \]
      3. remove-double-neg85.5%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(-1 + y\right)} \]
      4. +-commutative85.5%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + -1\right)}} \]
      5. distribute-neg-in85.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      6. neg-mul-185.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      7. *-commutative85.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      8. metadata-eval85.5%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      9. fma-def85.5%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr85.5%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/85.5%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity85.5%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef85.5%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. +-commutative85.5%

        \[\leadsto \frac{x}{\color{blue}{1 + y \cdot -1}} \]
      5. *-commutative85.5%

        \[\leadsto \frac{x}{1 + \color{blue}{-1 \cdot y}} \]
      6. neg-mul-185.5%

        \[\leadsto \frac{x}{1 + \color{blue}{\left(-y\right)}} \]
      7. unsub-neg85.5%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified85.5%

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

    if 3.5999999999999999e-100 < y < 4.1000000000000001e-17

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around 0 83.8%

      \[\leadsto \color{blue}{x} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification81.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -2.8 \cdot 10^{-35}:\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{elif}\;y \leq 6.1 \cdot 10^{-118}:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{elif}\;y \leq 3.6 \cdot 10^{-100} \lor \neg \left(y \leq 4.1 \cdot 10^{-17}\right):\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]

Alternative 4: 86.2% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 - \frac{x}{y}\\ t_1 := \frac{x}{1 - y}\\ \mathbf{if}\;y \leq -61000000:\\ \;\;\;\;t_0\\ \mathbf{elif}\;y \leq 6.1 \cdot 10^{-118}:\\ \;\;\;\;t_1\\ \mathbf{elif}\;y \leq 3.2 \cdot 10^{-100}:\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{elif}\;y \leq 320000000:\\ \;\;\;\;t_1\\ \mathbf{else}:\\ \;\;\;\;t_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (- 1.0 (/ x y))) (t_1 (/ x (- 1.0 y))))
   (if (<= y -61000000.0)
     t_0
     (if (<= y 6.1e-118)
       t_1
       (if (<= y 3.2e-100)
         (/ y (+ y -1.0))
         (if (<= y 320000000.0) t_1 t_0))))))
double code(double x, double y) {
	double t_0 = 1.0 - (x / y);
	double t_1 = x / (1.0 - y);
	double tmp;
	if (y <= -61000000.0) {
		tmp = t_0;
	} else if (y <= 6.1e-118) {
		tmp = t_1;
	} else if (y <= 3.2e-100) {
		tmp = y / (y + -1.0);
	} else if (y <= 320000000.0) {
		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 = 1.0d0 - (x / y)
    t_1 = x / (1.0d0 - y)
    if (y <= (-61000000.0d0)) then
        tmp = t_0
    else if (y <= 6.1d-118) then
        tmp = t_1
    else if (y <= 3.2d-100) then
        tmp = y / (y + (-1.0d0))
    else if (y <= 320000000.0d0) 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 = 1.0 - (x / y);
	double t_1 = x / (1.0 - y);
	double tmp;
	if (y <= -61000000.0) {
		tmp = t_0;
	} else if (y <= 6.1e-118) {
		tmp = t_1;
	} else if (y <= 3.2e-100) {
		tmp = y / (y + -1.0);
	} else if (y <= 320000000.0) {
		tmp = t_1;
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 - (x / y)
	t_1 = x / (1.0 - y)
	tmp = 0
	if y <= -61000000.0:
		tmp = t_0
	elif y <= 6.1e-118:
		tmp = t_1
	elif y <= 3.2e-100:
		tmp = y / (y + -1.0)
	elif y <= 320000000.0:
		tmp = t_1
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 - Float64(x / y))
	t_1 = Float64(x / Float64(1.0 - y))
	tmp = 0.0
	if (y <= -61000000.0)
		tmp = t_0;
	elseif (y <= 6.1e-118)
		tmp = t_1;
	elseif (y <= 3.2e-100)
		tmp = Float64(y / Float64(y + -1.0));
	elseif (y <= 320000000.0)
		tmp = t_1;
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = 1.0 - (x / y);
	t_1 = x / (1.0 - y);
	tmp = 0.0;
	if (y <= -61000000.0)
		tmp = t_0;
	elseif (y <= 6.1e-118)
		tmp = t_1;
	elseif (y <= 3.2e-100)
		tmp = y / (y + -1.0);
	elseif (y <= 320000000.0)
		tmp = t_1;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 - N[(x / y), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(x / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -61000000.0], t$95$0, If[LessEqual[y, 6.1e-118], t$95$1, If[LessEqual[y, 3.2e-100], N[(y / N[(y + -1.0), $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 320000000.0], t$95$1, t$95$0]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 - \frac{x}{y}\\
t_1 := \frac{x}{1 - y}\\
\mathbf{if}\;y \leq -61000000:\\
\;\;\;\;t_0\\

\mathbf{elif}\;y \leq 6.1 \cdot 10^{-118}:\\
\;\;\;\;t_1\\

\mathbf{elif}\;y \leq 3.2 \cdot 10^{-100}:\\
\;\;\;\;\frac{y}{y + -1}\\

\mathbf{elif}\;y \leq 320000000:\\
\;\;\;\;t_1\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if y < -6.1e7 or 3.2e8 < y

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 99.9%

      \[\leadsto \color{blue}{\frac{1}{y} + \left(1 + -1 \cdot \frac{x}{y}\right)} \]
    5. Step-by-step derivation
      1. +-commutative99.9%

        \[\leadsto \frac{1}{y} + \color{blue}{\left(-1 \cdot \frac{x}{y} + 1\right)} \]
      2. associate-+r+99.9%

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

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

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

        \[\leadsto \color{blue}{\frac{1 - x}{y}} + 1 \]
      6. unsub-neg99.9%

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

        \[\leadsto \frac{1 + \color{blue}{-1 \cdot x}}{y} + 1 \]
      8. +-commutative99.9%

        \[\leadsto \frac{\color{blue}{-1 \cdot x + 1}}{y} + 1 \]
      9. metadata-eval99.9%

        \[\leadsto \frac{-1 \cdot x + \color{blue}{-1 \cdot -1}}{y} + 1 \]
      10. distribute-lft-in99.9%

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

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

        \[\leadsto \frac{-1 \cdot \color{blue}{\left(x - 1\right)}}{y} + 1 \]
      13. associate-*r/99.9%

        \[\leadsto \color{blue}{-1 \cdot \frac{x - 1}{y}} + 1 \]
      14. +-commutative99.9%

        \[\leadsto \color{blue}{1 + -1 \cdot \frac{x - 1}{y}} \]
      15. associate-*r/99.9%

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

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

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

        \[\leadsto 1 + \frac{\color{blue}{-1 \cdot x + -1 \cdot -1}}{y} \]
      19. metadata-eval99.9%

        \[\leadsto 1 + \frac{-1 \cdot x + \color{blue}{1}}{y} \]
      20. +-commutative99.9%

        \[\leadsto 1 + \frac{\color{blue}{1 + -1 \cdot x}}{y} \]
      21. mul-1-neg99.9%

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

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

      \[\leadsto \color{blue}{1 + \frac{1 - x}{y}} \]
    7. Taylor expanded in x around inf 99.2%

      \[\leadsto 1 + \color{blue}{-1 \cdot \frac{x}{y}} \]
    8. Step-by-step derivation
      1. neg-mul-199.2%

        \[\leadsto 1 + \color{blue}{\left(-\frac{x}{y}\right)} \]
      2. distribute-neg-frac99.2%

        \[\leadsto 1 + \color{blue}{\frac{-x}{y}} \]
    9. Simplified99.2%

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

    if -6.1e7 < y < 6.09999999999999985e-118 or 3.20000000000000017e-100 < y < 3.2e8

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 80.7%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg80.7%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval80.7%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-180.7%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac80.7%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative80.7%

        \[\leadsto \frac{-x}{\color{blue}{-1 + y}} \]
    6. Simplified80.7%

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg80.7%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. div-inv80.7%

        \[\leadsto \color{blue}{\left(-\left(-x\right)\right) \cdot \frac{1}{-\left(-1 + y\right)}} \]
      3. remove-double-neg80.7%

        \[\leadsto \color{blue}{x} \cdot \frac{1}{-\left(-1 + y\right)} \]
      4. +-commutative80.7%

        \[\leadsto x \cdot \frac{1}{-\color{blue}{\left(y + -1\right)}} \]
      5. distribute-neg-in80.7%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      6. neg-mul-180.7%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      7. *-commutative80.7%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      8. metadata-eval80.7%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      9. fma-def80.7%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr80.7%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/80.7%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity80.7%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef80.7%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. +-commutative80.7%

        \[\leadsto \frac{x}{\color{blue}{1 + y \cdot -1}} \]
      5. *-commutative80.7%

        \[\leadsto \frac{x}{1 + \color{blue}{-1 \cdot y}} \]
      6. neg-mul-180.7%

        \[\leadsto \frac{x}{1 + \color{blue}{\left(-y\right)}} \]
      7. unsub-neg80.7%

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified80.7%

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

    if 6.09999999999999985e-118 < y < 3.20000000000000017e-100

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around 0 100.0%

      \[\leadsto \color{blue}{\frac{y}{y - 1}} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification90.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -61000000:\\ \;\;\;\;1 - \frac{x}{y}\\ \mathbf{elif}\;y \leq 6.1 \cdot 10^{-118}:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{elif}\;y \leq 3.2 \cdot 10^{-100}:\\ \;\;\;\;\frac{y}{y + -1}\\ \mathbf{elif}\;y \leq 320000000:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;1 - \frac{x}{y}\\ \end{array} \]

Alternative 5: 74.6% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.05 \cdot 10^{+44}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq 1.6 \cdot 10^{+33}:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -1.05e+44) 1.0 (if (<= y 1.6e+33) (/ x (- 1.0 y)) 1.0)))
double code(double x, double y) {
	double tmp;
	if (y <= -1.05e+44) {
		tmp = 1.0;
	} else if (y <= 1.6e+33) {
		tmp = x / (1.0 - y);
	} 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 (y <= (-1.05d+44)) then
        tmp = 1.0d0
    else if (y <= 1.6d+33) then
        tmp = x / (1.0d0 - y)
    else
        tmp = 1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -1.05e+44) {
		tmp = 1.0;
	} else if (y <= 1.6e+33) {
		tmp = x / (1.0 - y);
	} else {
		tmp = 1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -1.05e+44:
		tmp = 1.0
	elif y <= 1.6e+33:
		tmp = x / (1.0 - y)
	else:
		tmp = 1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -1.05e+44)
		tmp = 1.0;
	elseif (y <= 1.6e+33)
		tmp = Float64(x / Float64(1.0 - y));
	else
		tmp = 1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -1.05e+44)
		tmp = 1.0;
	elseif (y <= 1.6e+33)
		tmp = x / (1.0 - y);
	else
		tmp = 1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -1.05e+44], 1.0, If[LessEqual[y, 1.6e+33], N[(x / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], 1.0]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.05 \cdot 10^{+44}:\\
\;\;\;\;1\\

\mathbf{elif}\;y \leq 1.6 \cdot 10^{+33}:\\
\;\;\;\;\frac{x}{1 - y}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.04999999999999993e44 or 1.60000000000000009e33 < y

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 85.9%

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

    if -1.04999999999999993e44 < y < 1.60000000000000009e33

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in x around inf 74.1%

      \[\leadsto \color{blue}{-1 \cdot \frac{x}{y - 1}} \]
    5. Step-by-step derivation
      1. sub-neg74.1%

        \[\leadsto -1 \cdot \frac{x}{\color{blue}{y + \left(-1\right)}} \]
      2. metadata-eval74.1%

        \[\leadsto -1 \cdot \frac{x}{y + \color{blue}{-1}} \]
      3. neg-mul-174.1%

        \[\leadsto \color{blue}{-\frac{x}{y + -1}} \]
      4. distribute-neg-frac74.1%

        \[\leadsto \color{blue}{\frac{-x}{y + -1}} \]
      5. +-commutative74.1%

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

      \[\leadsto \color{blue}{\frac{-x}{-1 + y}} \]
    7. Step-by-step derivation
      1. frac-2neg74.1%

        \[\leadsto \color{blue}{\frac{-\left(-x\right)}{-\left(-1 + y\right)}} \]
      2. div-inv74.1%

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

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

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

        \[\leadsto x \cdot \frac{1}{\color{blue}{\left(-y\right) + \left(--1\right)}} \]
      6. neg-mul-174.1%

        \[\leadsto x \cdot \frac{1}{\color{blue}{-1 \cdot y} + \left(--1\right)} \]
      7. *-commutative74.1%

        \[\leadsto x \cdot \frac{1}{\color{blue}{y \cdot -1} + \left(--1\right)} \]
      8. metadata-eval74.1%

        \[\leadsto x \cdot \frac{1}{y \cdot -1 + \color{blue}{1}} \]
      9. fma-def74.1%

        \[\leadsto x \cdot \frac{1}{\color{blue}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    8. Applied egg-rr74.1%

      \[\leadsto \color{blue}{x \cdot \frac{1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
    9. Step-by-step derivation
      1. associate-*r/74.1%

        \[\leadsto \color{blue}{\frac{x \cdot 1}{\mathsf{fma}\left(y, -1, 1\right)}} \]
      2. *-rgt-identity74.1%

        \[\leadsto \frac{\color{blue}{x}}{\mathsf{fma}\left(y, -1, 1\right)} \]
      3. fma-udef74.1%

        \[\leadsto \frac{x}{\color{blue}{y \cdot -1 + 1}} \]
      4. +-commutative74.1%

        \[\leadsto \frac{x}{\color{blue}{1 + y \cdot -1}} \]
      5. *-commutative74.1%

        \[\leadsto \frac{x}{1 + \color{blue}{-1 \cdot y}} \]
      6. neg-mul-174.1%

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

        \[\leadsto \frac{x}{\color{blue}{1 - y}} \]
    10. Simplified74.1%

      \[\leadsto \color{blue}{\frac{x}{1 - y}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification79.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.05 \cdot 10^{+44}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq 1.6 \cdot 10^{+33}:\\ \;\;\;\;\frac{x}{1 - y}\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]

Alternative 6: 74.1% accurate, 1.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -1.3 \cdot 10^{-8}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= y -1.3e-8) 1.0 (if (<= y 1.0) x 1.0)))
double code(double x, double y) {
	double tmp;
	if (y <= -1.3e-8) {
		tmp = 1.0;
	} else if (y <= 1.0) {
		tmp = x;
	} 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 (y <= (-1.3d-8)) then
        tmp = 1.0d0
    else if (y <= 1.0d0) then
        tmp = x
    else
        tmp = 1.0d0
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double tmp;
	if (y <= -1.3e-8) {
		tmp = 1.0;
	} else if (y <= 1.0) {
		tmp = x;
	} else {
		tmp = 1.0;
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if y <= -1.3e-8:
		tmp = 1.0
	elif y <= 1.0:
		tmp = x
	else:
		tmp = 1.0
	return tmp
function code(x, y)
	tmp = 0.0
	if (y <= -1.3e-8)
		tmp = 1.0;
	elseif (y <= 1.0)
		tmp = x;
	else
		tmp = 1.0;
	end
	return tmp
end
function tmp_2 = code(x, y)
	tmp = 0.0;
	if (y <= -1.3e-8)
		tmp = 1.0;
	elseif (y <= 1.0)
		tmp = x;
	else
		tmp = 1.0;
	end
	tmp_2 = tmp;
end
code[x_, y_] := If[LessEqual[y, -1.3e-8], 1.0, If[LessEqual[y, 1.0], x, 1.0]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -1.3 \cdot 10^{-8}:\\
\;\;\;\;1\\

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

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.3000000000000001e-8 or 1 < y

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around inf 75.2%

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

    if -1.3000000000000001e-8 < y < 1

    1. Initial program 100.0%

      \[\frac{x - y}{1 - y} \]
    2. Step-by-step derivation
      1. sub-neg100.0%

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

        \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
      3. neg-sub0100.0%

        \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
      4. associate-+l-100.0%

        \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
      5. sub0-neg100.0%

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

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

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
      9. neg-sub0100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
      10. associate-+l-100.0%

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
      11. sub0-neg100.0%

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

        \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
      13. times-frac100.0%

        \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
      14. metadata-eval100.0%

        \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
      15. *-lft-identity100.0%

        \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
      16. sub-neg100.0%

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

        \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
    4. Taylor expanded in y around 0 78.6%

      \[\leadsto \color{blue}{x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification76.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.3 \cdot 10^{-8}:\\ \;\;\;\;1\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;1\\ \end{array} \]

Alternative 7: 39.7% accurate, 7.0× 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%

    \[\frac{x - y}{1 - y} \]
  2. Step-by-step derivation
    1. sub-neg100.0%

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

      \[\leadsto \frac{\color{blue}{\left(-y\right) + x}}{1 - y} \]
    3. neg-sub0100.0%

      \[\leadsto \frac{\color{blue}{\left(0 - y\right)} + x}{1 - y} \]
    4. associate-+l-100.0%

      \[\leadsto \frac{\color{blue}{0 - \left(y - x\right)}}{1 - y} \]
    5. sub0-neg100.0%

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

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

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

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(-y\right) + 1}} \]
    9. neg-sub0100.0%

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{\left(0 - y\right)} + 1} \]
    10. associate-+l-100.0%

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{0 - \left(y - 1\right)}} \]
    11. sub0-neg100.0%

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

      \[\leadsto \frac{-1 \cdot \left(y - x\right)}{\color{blue}{-1 \cdot \left(y - 1\right)}} \]
    13. times-frac100.0%

      \[\leadsto \color{blue}{\frac{-1}{-1} \cdot \frac{y - x}{y - 1}} \]
    14. metadata-eval100.0%

      \[\leadsto \color{blue}{1} \cdot \frac{y - x}{y - 1} \]
    15. *-lft-identity100.0%

      \[\leadsto \color{blue}{\frac{y - x}{y - 1}} \]
    16. sub-neg100.0%

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

      \[\leadsto \frac{y - x}{y + \color{blue}{-1}} \]
  3. Simplified100.0%

    \[\leadsto \color{blue}{\frac{y - x}{y + -1}} \]
  4. Taylor expanded in y around inf 42.0%

    \[\leadsto \color{blue}{1} \]
  5. Final simplification42.0%

    \[\leadsto 1 \]

Reproduce

?
herbie shell --seed 2023214 
(FPCore (x y)
  :name "Diagrams.Trail:splitAtParam  from diagrams-lib-1.3.0.3, C"
  :precision binary64
  (/ (- x y) (- 1.0 y)))