Numeric.SpecFunctions:invIncompleteGamma from math-functions-0.1.5.2, B

Percentage Accurate: 72.8% → 99.8%
Time: 8.0s
Alternatives: 9
Speedup: 1.0×

Specification

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

\\
1 - \log \left(1 - \frac{x - y}{1 - 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 9 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: 72.8% accurate, 1.0× speedup?

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

\\
1 - \log \left(1 - \frac{x - y}{1 - y}\right)
\end{array}

Alternative 1: 99.8% accurate, 0.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y - x}{-1 + y}\\ \mathbf{if}\;t\_0 \leq 0.95:\\ \;\;\;\;1 - \log \left(1 - t\_0\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{\left(x - \frac{1 - x}{y}\right) - 1}{y}\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (/ (- y x) (+ -1.0 y))))
   (if (<= t_0 0.95)
     (- 1.0 (log (- 1.0 t_0)))
     (- 1.0 (log (/ (- (- x (/ (- 1.0 x) y)) 1.0) y))))))
double code(double x, double y) {
	double t_0 = (y - x) / (-1.0 + y);
	double tmp;
	if (t_0 <= 0.95) {
		tmp = 1.0 - log((1.0 - t_0));
	} else {
		tmp = 1.0 - log((((x - ((1.0 - x) / y)) - 1.0) / 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 = (y - x) / ((-1.0d0) + y)
    if (t_0 <= 0.95d0) then
        tmp = 1.0d0 - log((1.0d0 - t_0))
    else
        tmp = 1.0d0 - log((((x - ((1.0d0 - x) / y)) - 1.0d0) / y))
    end if
    code = tmp
end function
public static double code(double x, double y) {
	double t_0 = (y - x) / (-1.0 + y);
	double tmp;
	if (t_0 <= 0.95) {
		tmp = 1.0 - Math.log((1.0 - t_0));
	} else {
		tmp = 1.0 - Math.log((((x - ((1.0 - x) / y)) - 1.0) / y));
	}
	return tmp;
}
def code(x, y):
	t_0 = (y - x) / (-1.0 + y)
	tmp = 0
	if t_0 <= 0.95:
		tmp = 1.0 - math.log((1.0 - t_0))
	else:
		tmp = 1.0 - math.log((((x - ((1.0 - x) / y)) - 1.0) / y))
	return tmp
function code(x, y)
	t_0 = Float64(Float64(y - x) / Float64(-1.0 + y))
	tmp = 0.0
	if (t_0 <= 0.95)
		tmp = Float64(1.0 - log(Float64(1.0 - t_0)));
	else
		tmp = Float64(1.0 - log(Float64(Float64(Float64(x - Float64(Float64(1.0 - x) / y)) - 1.0) / y)));
	end
	return tmp
end
function tmp_2 = code(x, y)
	t_0 = (y - x) / (-1.0 + y);
	tmp = 0.0;
	if (t_0 <= 0.95)
		tmp = 1.0 - log((1.0 - t_0));
	else
		tmp = 1.0 - log((((x - ((1.0 - x) / y)) - 1.0) / y));
	end
	tmp_2 = tmp;
end
code[x_, y_] := Block[{t$95$0 = N[(N[(y - x), $MachinePrecision] / N[(-1.0 + y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 0.95], N[(1.0 - N[Log[N[(1.0 - t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(N[(N[(x - N[(N[(1.0 - x), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision] - 1.0), $MachinePrecision] / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{y - x}{-1 + y}\\
\mathbf{if}\;t\_0 \leq 0.95:\\
\;\;\;\;1 - \log \left(1 - t\_0\right)\\

\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{\left(x - \frac{1 - x}{y}\right) - 1}{y}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.94999999999999996

    1. Initial program 100.0%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Add Preprocessing

    if 0.94999999999999996 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

    1. Initial program 8.0%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around -inf

      \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{\left(1 + -1 \cdot \frac{x - 1}{y}\right) - x}{y}\right)} \]
    4. Step-by-step derivation
      1. associate-*r/N/A

        \[\leadsto 1 - \log \color{blue}{\left(\frac{-1 \cdot \left(\left(1 + -1 \cdot \frac{x - 1}{y}\right) - x\right)}{y}\right)} \]
    5. Applied rewrites100.0%

      \[\leadsto 1 - \log \color{blue}{\left(\frac{\left(x - \frac{1 - x}{y}\right) - 1}{y}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification100.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{y - x}{-1 + y} \leq 0.95:\\ \;\;\;\;1 - \log \left(1 - \frac{y - x}{-1 + y}\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{\left(x - \frac{1 - x}{y}\right) - 1}{y}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 88.8% accurate, 0.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y - x}{-1 + y}\\ \mathbf{if}\;t\_0 \leq -20000000:\\ \;\;\;\;1 - \log \left(\frac{x}{-1 + y}\right)\\ \mathbf{elif}\;t\_0 \leq 4 \cdot 10^{-6}:\\ \;\;\;\;1 - \left(\mathsf{log1p}\left(-x\right) + y\right)\\ \mathbf{elif}\;t\_0 \leq 0.999999999998:\\ \;\;\;\;1 - \log \left(\frac{x}{y}\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (/ (- y x) (+ -1.0 y))))
   (if (<= t_0 -20000000.0)
     (- 1.0 (log (/ x (+ -1.0 y))))
     (if (<= t_0 4e-6)
       (- 1.0 (+ (log1p (- x)) y))
       (if (<= t_0 0.999999999998)
         (- 1.0 (log (/ x y)))
         (- 1.0 (log (/ -1.0 y))))))))
double code(double x, double y) {
	double t_0 = (y - x) / (-1.0 + y);
	double tmp;
	if (t_0 <= -20000000.0) {
		tmp = 1.0 - log((x / (-1.0 + y)));
	} else if (t_0 <= 4e-6) {
		tmp = 1.0 - (log1p(-x) + y);
	} else if (t_0 <= 0.999999999998) {
		tmp = 1.0 - log((x / y));
	} else {
		tmp = 1.0 - log((-1.0 / y));
	}
	return tmp;
}
public static double code(double x, double y) {
	double t_0 = (y - x) / (-1.0 + y);
	double tmp;
	if (t_0 <= -20000000.0) {
		tmp = 1.0 - Math.log((x / (-1.0 + y)));
	} else if (t_0 <= 4e-6) {
		tmp = 1.0 - (Math.log1p(-x) + y);
	} else if (t_0 <= 0.999999999998) {
		tmp = 1.0 - Math.log((x / y));
	} else {
		tmp = 1.0 - Math.log((-1.0 / y));
	}
	return tmp;
}
def code(x, y):
	t_0 = (y - x) / (-1.0 + y)
	tmp = 0
	if t_0 <= -20000000.0:
		tmp = 1.0 - math.log((x / (-1.0 + y)))
	elif t_0 <= 4e-6:
		tmp = 1.0 - (math.log1p(-x) + y)
	elif t_0 <= 0.999999999998:
		tmp = 1.0 - math.log((x / y))
	else:
		tmp = 1.0 - math.log((-1.0 / y))
	return tmp
function code(x, y)
	t_0 = Float64(Float64(y - x) / Float64(-1.0 + y))
	tmp = 0.0
	if (t_0 <= -20000000.0)
		tmp = Float64(1.0 - log(Float64(x / Float64(-1.0 + y))));
	elseif (t_0 <= 4e-6)
		tmp = Float64(1.0 - Float64(log1p(Float64(-x)) + y));
	elseif (t_0 <= 0.999999999998)
		tmp = Float64(1.0 - log(Float64(x / y)));
	else
		tmp = Float64(1.0 - log(Float64(-1.0 / y)));
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(N[(y - x), $MachinePrecision] / N[(-1.0 + y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -20000000.0], N[(1.0 - N[Log[N[(x / N[(-1.0 + y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 4e-6], N[(1.0 - N[(N[Log[1 + (-x)], $MachinePrecision] + y), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 0.999999999998], N[(1.0 - N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(-1.0 / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{y - x}{-1 + y}\\
\mathbf{if}\;t\_0 \leq -20000000:\\
\;\;\;\;1 - \log \left(\frac{x}{-1 + y}\right)\\

\mathbf{elif}\;t\_0 \leq 4 \cdot 10^{-6}:\\
\;\;\;\;1 - \left(\mathsf{log1p}\left(-x\right) + y\right)\\

\mathbf{elif}\;t\_0 \leq 0.999999999998:\\
\;\;\;\;1 - \log \left(\frac{x}{y}\right)\\

\mathbf{else}:\\
\;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < -2e7

    1. Initial program 100.0%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in x around inf

      \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{x}{1 - y}\right)} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{x}{1 - y}\right)\right)} \]
      2. distribute-neg-frac2N/A

        \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)} \]
      3. lower-/.f64N/A

        \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)} \]
      4. sub-negN/A

        \[\leadsto 1 - \log \left(\frac{x}{\mathsf{neg}\left(\color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)}\right)}\right) \]
      5. neg-mul-1N/A

        \[\leadsto 1 - \log \left(\frac{x}{\mathsf{neg}\left(\left(1 + \color{blue}{-1 \cdot y}\right)\right)}\right) \]
      6. distribute-neg-inN/A

        \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{\left(\mathsf{neg}\left(1\right)\right) + \left(\mathsf{neg}\left(-1 \cdot y\right)\right)}}\right) \]
      7. metadata-evalN/A

        \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{-1} + \left(\mathsf{neg}\left(-1 \cdot y\right)\right)}\right) \]
      8. neg-mul-1N/A

        \[\leadsto 1 - \log \left(\frac{x}{-1 + \left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(y\right)\right)}\right)\right)}\right) \]
      9. remove-double-negN/A

        \[\leadsto 1 - \log \left(\frac{x}{-1 + \color{blue}{y}}\right) \]
      10. lower-+.f6499.0

        \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{-1 + y}}\right) \]
    5. Applied rewrites99.0%

      \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{-1 + y}\right)} \]

    if -2e7 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 3.99999999999999982e-6

    1. Initial program 99.9%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around 0

      \[\leadsto 1 - \color{blue}{\left(\log \left(1 - x\right) + y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)} \]
    4. Step-by-step derivation
      1. distribute-rgt-inN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{\left(\left(-1 \cdot \frac{x}{1 - x}\right) \cdot y + \frac{1}{1 - x} \cdot y\right)}\right) \]
      2. +-commutativeN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{\left(\frac{1}{1 - x} \cdot y + \left(-1 \cdot \frac{x}{1 - x}\right) \cdot y\right)}\right) \]
      3. distribute-rgt-inN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{y \cdot \left(\frac{1}{1 - x} + -1 \cdot \frac{x}{1 - x}\right)}\right) \]
      4. mul-1-negN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 - x} + \color{blue}{\left(\mathsf{neg}\left(\frac{x}{1 - x}\right)\right)}\right)\right) \]
      5. sub-negN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \color{blue}{\left(\frac{1}{1 - x} - \frac{x}{1 - x}\right)}\right) \]
      6. sub-negN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{\color{blue}{1 + \left(\mathsf{neg}\left(x\right)\right)}} - \frac{x}{1 - x}\right)\right) \]
      7. mul-1-negN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 + \color{blue}{-1 \cdot x}} - \frac{x}{1 - x}\right)\right) \]
      8. sub-negN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 + -1 \cdot x} - \frac{x}{\color{blue}{1 + \left(\mathsf{neg}\left(x\right)\right)}}\right)\right) \]
      9. mul-1-negN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 + -1 \cdot x} - \frac{x}{1 + \color{blue}{-1 \cdot x}}\right)\right) \]
      10. div-subN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \color{blue}{\frac{1 - x}{1 + -1 \cdot x}}\right) \]
      11. sub-negN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \frac{\color{blue}{1 + \left(\mathsf{neg}\left(x\right)\right)}}{1 + -1 \cdot x}\right) \]
      12. mul-1-negN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \frac{1 + \color{blue}{-1 \cdot x}}{1 + -1 \cdot x}\right) \]
      13. *-inversesN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \color{blue}{1}\right) \]
      14. *-rgt-identityN/A

        \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{y}\right) \]
      15. lower-+.f64N/A

        \[\leadsto 1 - \color{blue}{\left(\log \left(1 - x\right) + y\right)} \]
    5. Applied rewrites99.8%

      \[\leadsto 1 - \color{blue}{\left(\mathsf{log1p}\left(-x\right) + y\right)} \]

    if 3.99999999999999982e-6 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.99999999999800004

    1. Initial program 77.3%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Add Preprocessing
    3. Taylor expanded in y around inf

      \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
    4. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{1 + -1 \cdot x}{y}\right)\right)} \]
      2. distribute-frac-negN/A

        \[\leadsto 1 - \log \color{blue}{\left(\frac{\mathsf{neg}\left(\left(1 + -1 \cdot x\right)\right)}{y}\right)} \]
      3. +-commutativeN/A

        \[\leadsto 1 - \log \left(\frac{\mathsf{neg}\left(\color{blue}{\left(-1 \cdot x + 1\right)}\right)}{y}\right) \]
      4. distribute-neg-inN/A

        \[\leadsto 1 - \log \left(\frac{\color{blue}{\left(\mathsf{neg}\left(-1 \cdot x\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}{y}\right) \]
      5. mul-1-negN/A

        \[\leadsto 1 - \log \left(\frac{\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
      6. remove-double-negN/A

        \[\leadsto 1 - \log \left(\frac{\color{blue}{x} + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
      7. sub-negN/A

        \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
      8. lower-/.f64N/A

        \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
      9. lower--.f6487.5

        \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
    5. Applied rewrites87.5%

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

      \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{y}}\right) \]
    7. Step-by-step derivation
      1. Applied rewrites85.5%

        \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{y}}\right) \]

      if 0.99999999999800004 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

      1. Initial program 4.6%

        \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
      2. Add Preprocessing
      3. Taylor expanded in y around inf

        \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
      4. Step-by-step derivation
        1. mul-1-negN/A

          \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{1 + -1 \cdot x}{y}\right)\right)} \]
        2. distribute-frac-negN/A

          \[\leadsto 1 - \log \color{blue}{\left(\frac{\mathsf{neg}\left(\left(1 + -1 \cdot x\right)\right)}{y}\right)} \]
        3. +-commutativeN/A

          \[\leadsto 1 - \log \left(\frac{\mathsf{neg}\left(\color{blue}{\left(-1 \cdot x + 1\right)}\right)}{y}\right) \]
        4. distribute-neg-inN/A

          \[\leadsto 1 - \log \left(\frac{\color{blue}{\left(\mathsf{neg}\left(-1 \cdot x\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}{y}\right) \]
        5. mul-1-negN/A

          \[\leadsto 1 - \log \left(\frac{\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
        6. remove-double-negN/A

          \[\leadsto 1 - \log \left(\frac{\color{blue}{x} + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
        7. sub-negN/A

          \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
        8. lower-/.f64N/A

          \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
        9. lower--.f6499.8

          \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
      5. Applied rewrites99.8%

        \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
      6. Taylor expanded in x around 0

        \[\leadsto 1 - \log \left(\frac{-1}{\color{blue}{y}}\right) \]
      7. Step-by-step derivation
        1. Applied rewrites66.6%

          \[\leadsto 1 - \log \left(\frac{-1}{\color{blue}{y}}\right) \]
      8. Recombined 4 regimes into one program.
      9. Final simplification90.5%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{y - x}{-1 + y} \leq -20000000:\\ \;\;\;\;1 - \log \left(\frac{x}{-1 + y}\right)\\ \mathbf{elif}\;\frac{y - x}{-1 + y} \leq 4 \cdot 10^{-6}:\\ \;\;\;\;1 - \left(\mathsf{log1p}\left(-x\right) + y\right)\\ \mathbf{elif}\;\frac{y - x}{-1 + y} \leq 0.999999999998:\\ \;\;\;\;1 - \log \left(\frac{x}{y}\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\ \end{array} \]
      10. Add Preprocessing

      Alternative 3: 97.9% accurate, 0.8× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y - x}{-1 + y}\\ \mathbf{if}\;t\_0 \leq -20000000:\\ \;\;\;\;1 - \log \left(\frac{x}{-1 + y}\right)\\ \mathbf{elif}\;t\_0 \leq 4 \cdot 10^{-6}:\\ \;\;\;\;1 - \left(\mathsf{log1p}\left(-x\right) + y\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{x - 1}{y}\right)\\ \end{array} \end{array} \]
      (FPCore (x y)
       :precision binary64
       (let* ((t_0 (/ (- y x) (+ -1.0 y))))
         (if (<= t_0 -20000000.0)
           (- 1.0 (log (/ x (+ -1.0 y))))
           (if (<= t_0 4e-6)
             (- 1.0 (+ (log1p (- x)) y))
             (- 1.0 (log (/ (- x 1.0) y)))))))
      double code(double x, double y) {
      	double t_0 = (y - x) / (-1.0 + y);
      	double tmp;
      	if (t_0 <= -20000000.0) {
      		tmp = 1.0 - log((x / (-1.0 + y)));
      	} else if (t_0 <= 4e-6) {
      		tmp = 1.0 - (log1p(-x) + y);
      	} else {
      		tmp = 1.0 - log(((x - 1.0) / y));
      	}
      	return tmp;
      }
      
      public static double code(double x, double y) {
      	double t_0 = (y - x) / (-1.0 + y);
      	double tmp;
      	if (t_0 <= -20000000.0) {
      		tmp = 1.0 - Math.log((x / (-1.0 + y)));
      	} else if (t_0 <= 4e-6) {
      		tmp = 1.0 - (Math.log1p(-x) + y);
      	} else {
      		tmp = 1.0 - Math.log(((x - 1.0) / y));
      	}
      	return tmp;
      }
      
      def code(x, y):
      	t_0 = (y - x) / (-1.0 + y)
      	tmp = 0
      	if t_0 <= -20000000.0:
      		tmp = 1.0 - math.log((x / (-1.0 + y)))
      	elif t_0 <= 4e-6:
      		tmp = 1.0 - (math.log1p(-x) + y)
      	else:
      		tmp = 1.0 - math.log(((x - 1.0) / y))
      	return tmp
      
      function code(x, y)
      	t_0 = Float64(Float64(y - x) / Float64(-1.0 + y))
      	tmp = 0.0
      	if (t_0 <= -20000000.0)
      		tmp = Float64(1.0 - log(Float64(x / Float64(-1.0 + y))));
      	elseif (t_0 <= 4e-6)
      		tmp = Float64(1.0 - Float64(log1p(Float64(-x)) + y));
      	else
      		tmp = Float64(1.0 - log(Float64(Float64(x - 1.0) / y)));
      	end
      	return tmp
      end
      
      code[x_, y_] := Block[{t$95$0 = N[(N[(y - x), $MachinePrecision] / N[(-1.0 + y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, -20000000.0], N[(1.0 - N[Log[N[(x / N[(-1.0 + y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 4e-6], N[(1.0 - N[(N[Log[1 + (-x)], $MachinePrecision] + y), $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(N[(x - 1.0), $MachinePrecision] / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \frac{y - x}{-1 + y}\\
      \mathbf{if}\;t\_0 \leq -20000000:\\
      \;\;\;\;1 - \log \left(\frac{x}{-1 + y}\right)\\
      
      \mathbf{elif}\;t\_0 \leq 4 \cdot 10^{-6}:\\
      \;\;\;\;1 - \left(\mathsf{log1p}\left(-x\right) + y\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;1 - \log \left(\frac{x - 1}{y}\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 3 regimes
      2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < -2e7

        1. Initial program 100.0%

          \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
        2. Add Preprocessing
        3. Taylor expanded in x around inf

          \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{x}{1 - y}\right)} \]
        4. Step-by-step derivation
          1. mul-1-negN/A

            \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{x}{1 - y}\right)\right)} \]
          2. distribute-neg-frac2N/A

            \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)} \]
          3. lower-/.f64N/A

            \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)} \]
          4. sub-negN/A

            \[\leadsto 1 - \log \left(\frac{x}{\mathsf{neg}\left(\color{blue}{\left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)}\right)}\right) \]
          5. neg-mul-1N/A

            \[\leadsto 1 - \log \left(\frac{x}{\mathsf{neg}\left(\left(1 + \color{blue}{-1 \cdot y}\right)\right)}\right) \]
          6. distribute-neg-inN/A

            \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{\left(\mathsf{neg}\left(1\right)\right) + \left(\mathsf{neg}\left(-1 \cdot y\right)\right)}}\right) \]
          7. metadata-evalN/A

            \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{-1} + \left(\mathsf{neg}\left(-1 \cdot y\right)\right)}\right) \]
          8. neg-mul-1N/A

            \[\leadsto 1 - \log \left(\frac{x}{-1 + \left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(y\right)\right)}\right)\right)}\right) \]
          9. remove-double-negN/A

            \[\leadsto 1 - \log \left(\frac{x}{-1 + \color{blue}{y}}\right) \]
          10. lower-+.f6499.0

            \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{-1 + y}}\right) \]
        5. Applied rewrites99.0%

          \[\leadsto 1 - \log \color{blue}{\left(\frac{x}{-1 + y}\right)} \]

        if -2e7 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 3.99999999999999982e-6

        1. Initial program 99.9%

          \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
        2. Add Preprocessing
        3. Taylor expanded in y around 0

          \[\leadsto 1 - \color{blue}{\left(\log \left(1 - x\right) + y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)} \]
        4. Step-by-step derivation
          1. distribute-rgt-inN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{\left(\left(-1 \cdot \frac{x}{1 - x}\right) \cdot y + \frac{1}{1 - x} \cdot y\right)}\right) \]
          2. +-commutativeN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{\left(\frac{1}{1 - x} \cdot y + \left(-1 \cdot \frac{x}{1 - x}\right) \cdot y\right)}\right) \]
          3. distribute-rgt-inN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{y \cdot \left(\frac{1}{1 - x} + -1 \cdot \frac{x}{1 - x}\right)}\right) \]
          4. mul-1-negN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 - x} + \color{blue}{\left(\mathsf{neg}\left(\frac{x}{1 - x}\right)\right)}\right)\right) \]
          5. sub-negN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \color{blue}{\left(\frac{1}{1 - x} - \frac{x}{1 - x}\right)}\right) \]
          6. sub-negN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{\color{blue}{1 + \left(\mathsf{neg}\left(x\right)\right)}} - \frac{x}{1 - x}\right)\right) \]
          7. mul-1-negN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 + \color{blue}{-1 \cdot x}} - \frac{x}{1 - x}\right)\right) \]
          8. sub-negN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 + -1 \cdot x} - \frac{x}{\color{blue}{1 + \left(\mathsf{neg}\left(x\right)\right)}}\right)\right) \]
          9. mul-1-negN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 + -1 \cdot x} - \frac{x}{1 + \color{blue}{-1 \cdot x}}\right)\right) \]
          10. div-subN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \color{blue}{\frac{1 - x}{1 + -1 \cdot x}}\right) \]
          11. sub-negN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \frac{\color{blue}{1 + \left(\mathsf{neg}\left(x\right)\right)}}{1 + -1 \cdot x}\right) \]
          12. mul-1-negN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \frac{1 + \color{blue}{-1 \cdot x}}{1 + -1 \cdot x}\right) \]
          13. *-inversesN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \color{blue}{1}\right) \]
          14. *-rgt-identityN/A

            \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{y}\right) \]
          15. lower-+.f64N/A

            \[\leadsto 1 - \color{blue}{\left(\log \left(1 - x\right) + y\right)} \]
        5. Applied rewrites99.8%

          \[\leadsto 1 - \color{blue}{\left(\mathsf{log1p}\left(-x\right) + y\right)} \]

        if 3.99999999999999982e-6 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

        1. Initial program 10.5%

          \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
        2. Add Preprocessing
        3. Taylor expanded in y around inf

          \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
        4. Step-by-step derivation
          1. mul-1-negN/A

            \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{1 + -1 \cdot x}{y}\right)\right)} \]
          2. distribute-frac-negN/A

            \[\leadsto 1 - \log \color{blue}{\left(\frac{\mathsf{neg}\left(\left(1 + -1 \cdot x\right)\right)}{y}\right)} \]
          3. +-commutativeN/A

            \[\leadsto 1 - \log \left(\frac{\mathsf{neg}\left(\color{blue}{\left(-1 \cdot x + 1\right)}\right)}{y}\right) \]
          4. distribute-neg-inN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{\left(\mathsf{neg}\left(-1 \cdot x\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}{y}\right) \]
          5. mul-1-negN/A

            \[\leadsto 1 - \log \left(\frac{\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
          6. remove-double-negN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x} + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
          7. sub-negN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
          8. lower-/.f64N/A

            \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
          9. lower--.f6498.8

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
        5. Applied rewrites98.8%

          \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
      3. Recombined 3 regimes into one program.
      4. Final simplification99.2%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{y - x}{-1 + y} \leq -20000000:\\ \;\;\;\;1 - \log \left(\frac{x}{-1 + y}\right)\\ \mathbf{elif}\;\frac{y - x}{-1 + y} \leq 4 \cdot 10^{-6}:\\ \;\;\;\;1 - \left(\mathsf{log1p}\left(-x\right) + y\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{x - 1}{y}\right)\\ \end{array} \]
      5. Add Preprocessing

      Alternative 4: 99.6% accurate, 0.8× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{y - x}{-1 + y}\\ \mathbf{if}\;t\_0 \leq 0.95:\\ \;\;\;\;1 - \log \left(1 - t\_0\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{x - 1}{y}\right)\\ \end{array} \end{array} \]
      (FPCore (x y)
       :precision binary64
       (let* ((t_0 (/ (- y x) (+ -1.0 y))))
         (if (<= t_0 0.95) (- 1.0 (log (- 1.0 t_0))) (- 1.0 (log (/ (- x 1.0) y))))))
      double code(double x, double y) {
      	double t_0 = (y - x) / (-1.0 + y);
      	double tmp;
      	if (t_0 <= 0.95) {
      		tmp = 1.0 - log((1.0 - t_0));
      	} else {
      		tmp = 1.0 - log(((x - 1.0) / 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 = (y - x) / ((-1.0d0) + y)
          if (t_0 <= 0.95d0) then
              tmp = 1.0d0 - log((1.0d0 - t_0))
          else
              tmp = 1.0d0 - log(((x - 1.0d0) / y))
          end if
          code = tmp
      end function
      
      public static double code(double x, double y) {
      	double t_0 = (y - x) / (-1.0 + y);
      	double tmp;
      	if (t_0 <= 0.95) {
      		tmp = 1.0 - Math.log((1.0 - t_0));
      	} else {
      		tmp = 1.0 - Math.log(((x - 1.0) / y));
      	}
      	return tmp;
      }
      
      def code(x, y):
      	t_0 = (y - x) / (-1.0 + y)
      	tmp = 0
      	if t_0 <= 0.95:
      		tmp = 1.0 - math.log((1.0 - t_0))
      	else:
      		tmp = 1.0 - math.log(((x - 1.0) / y))
      	return tmp
      
      function code(x, y)
      	t_0 = Float64(Float64(y - x) / Float64(-1.0 + y))
      	tmp = 0.0
      	if (t_0 <= 0.95)
      		tmp = Float64(1.0 - log(Float64(1.0 - t_0)));
      	else
      		tmp = Float64(1.0 - log(Float64(Float64(x - 1.0) / y)));
      	end
      	return tmp
      end
      
      function tmp_2 = code(x, y)
      	t_0 = (y - x) / (-1.0 + y);
      	tmp = 0.0;
      	if (t_0 <= 0.95)
      		tmp = 1.0 - log((1.0 - t_0));
      	else
      		tmp = 1.0 - log(((x - 1.0) / y));
      	end
      	tmp_2 = tmp;
      end
      
      code[x_, y_] := Block[{t$95$0 = N[(N[(y - x), $MachinePrecision] / N[(-1.0 + y), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 0.95], N[(1.0 - N[Log[N[(1.0 - t$95$0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(N[(x - 1.0), $MachinePrecision] / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \frac{y - x}{-1 + y}\\
      \mathbf{if}\;t\_0 \leq 0.95:\\
      \;\;\;\;1 - \log \left(1 - t\_0\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;1 - \log \left(\frac{x - 1}{y}\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.94999999999999996

        1. Initial program 100.0%

          \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
        2. Add Preprocessing

        if 0.94999999999999996 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

        1. Initial program 8.0%

          \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
        2. Add Preprocessing
        3. Taylor expanded in y around inf

          \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
        4. Step-by-step derivation
          1. mul-1-negN/A

            \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{1 + -1 \cdot x}{y}\right)\right)} \]
          2. distribute-frac-negN/A

            \[\leadsto 1 - \log \color{blue}{\left(\frac{\mathsf{neg}\left(\left(1 + -1 \cdot x\right)\right)}{y}\right)} \]
          3. +-commutativeN/A

            \[\leadsto 1 - \log \left(\frac{\mathsf{neg}\left(\color{blue}{\left(-1 \cdot x + 1\right)}\right)}{y}\right) \]
          4. distribute-neg-inN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{\left(\mathsf{neg}\left(-1 \cdot x\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}{y}\right) \]
          5. mul-1-negN/A

            \[\leadsto 1 - \log \left(\frac{\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
          6. remove-double-negN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x} + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
          7. sub-negN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
          8. lower-/.f64N/A

            \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
          9. lower--.f6499.8

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
        5. Applied rewrites99.8%

          \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification99.9%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{y - x}{-1 + y} \leq 0.95:\\ \;\;\;\;1 - \log \left(1 - \frac{y - x}{-1 + y}\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{x - 1}{y}\right)\\ \end{array} \]
      5. Add Preprocessing

      Alternative 5: 79.2% accurate, 0.9× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{y - x}{-1 + y} \leq 4 \cdot 10^{-6}:\\ \;\;\;\;1 - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\ \end{array} \end{array} \]
      (FPCore (x y)
       :precision binary64
       (if (<= (/ (- y x) (+ -1.0 y)) 4e-6)
         (- 1.0 (log1p (- x)))
         (- 1.0 (log (/ -1.0 y)))))
      double code(double x, double y) {
      	double tmp;
      	if (((y - x) / (-1.0 + y)) <= 4e-6) {
      		tmp = 1.0 - log1p(-x);
      	} else {
      		tmp = 1.0 - log((-1.0 / y));
      	}
      	return tmp;
      }
      
      public static double code(double x, double y) {
      	double tmp;
      	if (((y - x) / (-1.0 + y)) <= 4e-6) {
      		tmp = 1.0 - Math.log1p(-x);
      	} else {
      		tmp = 1.0 - Math.log((-1.0 / y));
      	}
      	return tmp;
      }
      
      def code(x, y):
      	tmp = 0
      	if ((y - x) / (-1.0 + y)) <= 4e-6:
      		tmp = 1.0 - math.log1p(-x)
      	else:
      		tmp = 1.0 - math.log((-1.0 / y))
      	return tmp
      
      function code(x, y)
      	tmp = 0.0
      	if (Float64(Float64(y - x) / Float64(-1.0 + y)) <= 4e-6)
      		tmp = Float64(1.0 - log1p(Float64(-x)));
      	else
      		tmp = Float64(1.0 - log(Float64(-1.0 / y)));
      	end
      	return tmp
      end
      
      code[x_, y_] := If[LessEqual[N[(N[(y - x), $MachinePrecision] / N[(-1.0 + y), $MachinePrecision]), $MachinePrecision], 4e-6], N[(1.0 - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(-1.0 / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\frac{y - x}{-1 + y} \leq 4 \cdot 10^{-6}:\\
      \;\;\;\;1 - \mathsf{log1p}\left(-x\right)\\
      
      \mathbf{else}:\\
      \;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 3.99999999999999982e-6

        1. Initial program 100.0%

          \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
        2. Add Preprocessing
        3. Taylor expanded in y around 0

          \[\leadsto 1 - \color{blue}{\log \left(1 - x\right)} \]
        4. Step-by-step derivation
          1. sub-negN/A

            \[\leadsto 1 - \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(x\right)\right)\right)} \]
          2. mul-1-negN/A

            \[\leadsto 1 - \log \left(1 + \color{blue}{-1 \cdot x}\right) \]
          3. lower-log1p.f64N/A

            \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-1 \cdot x\right)} \]
          4. mul-1-negN/A

            \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\mathsf{neg}\left(x\right)}\right) \]
          5. lower-neg.f6485.2

            \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{-x}\right) \]
        5. Applied rewrites85.2%

          \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-x\right)} \]

        if 3.99999999999999982e-6 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

        1. Initial program 10.5%

          \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
        2. Add Preprocessing
        3. Taylor expanded in y around inf

          \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
        4. Step-by-step derivation
          1. mul-1-negN/A

            \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{1 + -1 \cdot x}{y}\right)\right)} \]
          2. distribute-frac-negN/A

            \[\leadsto 1 - \log \color{blue}{\left(\frac{\mathsf{neg}\left(\left(1 + -1 \cdot x\right)\right)}{y}\right)} \]
          3. +-commutativeN/A

            \[\leadsto 1 - \log \left(\frac{\mathsf{neg}\left(\color{blue}{\left(-1 \cdot x + 1\right)}\right)}{y}\right) \]
          4. distribute-neg-inN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{\left(\mathsf{neg}\left(-1 \cdot x\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}{y}\right) \]
          5. mul-1-negN/A

            \[\leadsto 1 - \log \left(\frac{\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
          6. remove-double-negN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x} + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
          7. sub-negN/A

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
          8. lower-/.f64N/A

            \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
          9. lower--.f6498.8

            \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
        5. Applied rewrites98.8%

          \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
        6. Taylor expanded in x around 0

          \[\leadsto 1 - \log \left(\frac{-1}{\color{blue}{y}}\right) \]
        7. Step-by-step derivation
          1. Applied rewrites61.6%

            \[\leadsto 1 - \log \left(\frac{-1}{\color{blue}{y}}\right) \]
        8. Recombined 2 regimes into one program.
        9. Final simplification78.5%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{y - x}{-1 + y} \leq 4 \cdot 10^{-6}:\\ \;\;\;\;1 - \mathsf{log1p}\left(-x\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\ \end{array} \]
        10. Add Preprocessing

        Alternative 6: 89.1% accurate, 1.0× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -12.5:\\ \;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;1 - \left(\mathsf{log1p}\left(-x\right) + y\right)\\ \mathbf{else}:\\ \;\;\;\;1 - \log \left(\frac{x}{y}\right)\\ \end{array} \end{array} \]
        (FPCore (x y)
         :precision binary64
         (if (<= y -12.5)
           (- 1.0 (log (/ -1.0 y)))
           (if (<= y 1.0) (- 1.0 (+ (log1p (- x)) y)) (- 1.0 (log (/ x y))))))
        double code(double x, double y) {
        	double tmp;
        	if (y <= -12.5) {
        		tmp = 1.0 - log((-1.0 / y));
        	} else if (y <= 1.0) {
        		tmp = 1.0 - (log1p(-x) + y);
        	} else {
        		tmp = 1.0 - log((x / y));
        	}
        	return tmp;
        }
        
        public static double code(double x, double y) {
        	double tmp;
        	if (y <= -12.5) {
        		tmp = 1.0 - Math.log((-1.0 / y));
        	} else if (y <= 1.0) {
        		tmp = 1.0 - (Math.log1p(-x) + y);
        	} else {
        		tmp = 1.0 - Math.log((x / y));
        	}
        	return tmp;
        }
        
        def code(x, y):
        	tmp = 0
        	if y <= -12.5:
        		tmp = 1.0 - math.log((-1.0 / y))
        	elif y <= 1.0:
        		tmp = 1.0 - (math.log1p(-x) + y)
        	else:
        		tmp = 1.0 - math.log((x / y))
        	return tmp
        
        function code(x, y)
        	tmp = 0.0
        	if (y <= -12.5)
        		tmp = Float64(1.0 - log(Float64(-1.0 / y)));
        	elseif (y <= 1.0)
        		tmp = Float64(1.0 - Float64(log1p(Float64(-x)) + y));
        	else
        		tmp = Float64(1.0 - log(Float64(x / y)));
        	end
        	return tmp
        end
        
        code[x_, y_] := If[LessEqual[y, -12.5], N[(1.0 - N[Log[N[(-1.0 / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[y, 1.0], N[(1.0 - N[(N[Log[1 + (-x)], $MachinePrecision] + y), $MachinePrecision]), $MachinePrecision], N[(1.0 - N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;y \leq -12.5:\\
        \;\;\;\;1 - \log \left(\frac{-1}{y}\right)\\
        
        \mathbf{elif}\;y \leq 1:\\
        \;\;\;\;1 - \left(\mathsf{log1p}\left(-x\right) + y\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;1 - \log \left(\frac{x}{y}\right)\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 3 regimes
        2. if y < -12.5

          1. Initial program 27.6%

            \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
          2. Add Preprocessing
          3. Taylor expanded in y around inf

            \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
          4. Step-by-step derivation
            1. mul-1-negN/A

              \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{1 + -1 \cdot x}{y}\right)\right)} \]
            2. distribute-frac-negN/A

              \[\leadsto 1 - \log \color{blue}{\left(\frac{\mathsf{neg}\left(\left(1 + -1 \cdot x\right)\right)}{y}\right)} \]
            3. +-commutativeN/A

              \[\leadsto 1 - \log \left(\frac{\mathsf{neg}\left(\color{blue}{\left(-1 \cdot x + 1\right)}\right)}{y}\right) \]
            4. distribute-neg-inN/A

              \[\leadsto 1 - \log \left(\frac{\color{blue}{\left(\mathsf{neg}\left(-1 \cdot x\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}{y}\right) \]
            5. mul-1-negN/A

              \[\leadsto 1 - \log \left(\frac{\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
            6. remove-double-negN/A

              \[\leadsto 1 - \log \left(\frac{\color{blue}{x} + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
            7. sub-negN/A

              \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
            8. lower-/.f64N/A

              \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
            9. lower--.f6498.6

              \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
          5. Applied rewrites98.6%

            \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
          6. Taylor expanded in x around 0

            \[\leadsto 1 - \log \left(\frac{-1}{\color{blue}{y}}\right) \]
          7. Step-by-step derivation
            1. Applied rewrites60.3%

              \[\leadsto 1 - \log \left(\frac{-1}{\color{blue}{y}}\right) \]

            if -12.5 < y < 1

            1. Initial program 100.0%

              \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
            2. Add Preprocessing
            3. Taylor expanded in y around 0

              \[\leadsto 1 - \color{blue}{\left(\log \left(1 - x\right) + y \cdot \left(-1 \cdot \frac{x}{1 - x} + \frac{1}{1 - x}\right)\right)} \]
            4. Step-by-step derivation
              1. distribute-rgt-inN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{\left(\left(-1 \cdot \frac{x}{1 - x}\right) \cdot y + \frac{1}{1 - x} \cdot y\right)}\right) \]
              2. +-commutativeN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{\left(\frac{1}{1 - x} \cdot y + \left(-1 \cdot \frac{x}{1 - x}\right) \cdot y\right)}\right) \]
              3. distribute-rgt-inN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{y \cdot \left(\frac{1}{1 - x} + -1 \cdot \frac{x}{1 - x}\right)}\right) \]
              4. mul-1-negN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 - x} + \color{blue}{\left(\mathsf{neg}\left(\frac{x}{1 - x}\right)\right)}\right)\right) \]
              5. sub-negN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \color{blue}{\left(\frac{1}{1 - x} - \frac{x}{1 - x}\right)}\right) \]
              6. sub-negN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{\color{blue}{1 + \left(\mathsf{neg}\left(x\right)\right)}} - \frac{x}{1 - x}\right)\right) \]
              7. mul-1-negN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 + \color{blue}{-1 \cdot x}} - \frac{x}{1 - x}\right)\right) \]
              8. sub-negN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 + -1 \cdot x} - \frac{x}{\color{blue}{1 + \left(\mathsf{neg}\left(x\right)\right)}}\right)\right) \]
              9. mul-1-negN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \left(\frac{1}{1 + -1 \cdot x} - \frac{x}{1 + \color{blue}{-1 \cdot x}}\right)\right) \]
              10. div-subN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \color{blue}{\frac{1 - x}{1 + -1 \cdot x}}\right) \]
              11. sub-negN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \frac{\color{blue}{1 + \left(\mathsf{neg}\left(x\right)\right)}}{1 + -1 \cdot x}\right) \]
              12. mul-1-negN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \frac{1 + \color{blue}{-1 \cdot x}}{1 + -1 \cdot x}\right) \]
              13. *-inversesN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + y \cdot \color{blue}{1}\right) \]
              14. *-rgt-identityN/A

                \[\leadsto 1 - \left(\log \left(1 - x\right) + \color{blue}{y}\right) \]
              15. lower-+.f64N/A

                \[\leadsto 1 - \color{blue}{\left(\log \left(1 - x\right) + y\right)} \]
            5. Applied rewrites99.3%

              \[\leadsto 1 - \color{blue}{\left(\mathsf{log1p}\left(-x\right) + y\right)} \]

            if 1 < y

            1. Initial program 57.6%

              \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
            2. Add Preprocessing
            3. Taylor expanded in y around inf

              \[\leadsto 1 - \log \color{blue}{\left(-1 \cdot \frac{1 + -1 \cdot x}{y}\right)} \]
            4. Step-by-step derivation
              1. mul-1-negN/A

                \[\leadsto 1 - \log \color{blue}{\left(\mathsf{neg}\left(\frac{1 + -1 \cdot x}{y}\right)\right)} \]
              2. distribute-frac-negN/A

                \[\leadsto 1 - \log \color{blue}{\left(\frac{\mathsf{neg}\left(\left(1 + -1 \cdot x\right)\right)}{y}\right)} \]
              3. +-commutativeN/A

                \[\leadsto 1 - \log \left(\frac{\mathsf{neg}\left(\color{blue}{\left(-1 \cdot x + 1\right)}\right)}{y}\right) \]
              4. distribute-neg-inN/A

                \[\leadsto 1 - \log \left(\frac{\color{blue}{\left(\mathsf{neg}\left(-1 \cdot x\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}}{y}\right) \]
              5. mul-1-negN/A

                \[\leadsto 1 - \log \left(\frac{\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(x\right)\right)}\right)\right) + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
              6. remove-double-negN/A

                \[\leadsto 1 - \log \left(\frac{\color{blue}{x} + \left(\mathsf{neg}\left(1\right)\right)}{y}\right) \]
              7. sub-negN/A

                \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
              8. lower-/.f64N/A

                \[\leadsto 1 - \log \color{blue}{\left(\frac{x - 1}{y}\right)} \]
              9. lower--.f6498.3

                \[\leadsto 1 - \log \left(\frac{\color{blue}{x - 1}}{y}\right) \]
            5. Applied rewrites98.3%

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

              \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{y}}\right) \]
            7. Step-by-step derivation
              1. Applied rewrites95.0%

                \[\leadsto 1 - \log \left(\frac{x}{\color{blue}{y}}\right) \]
            8. Recombined 3 regimes into one program.
            9. Add Preprocessing

            Alternative 7: 62.8% accurate, 1.2× speedup?

            \[\begin{array}{l} \\ 1 - \mathsf{log1p}\left(-x\right) \end{array} \]
            (FPCore (x y) :precision binary64 (- 1.0 (log1p (- x))))
            double code(double x, double y) {
            	return 1.0 - log1p(-x);
            }
            
            public static double code(double x, double y) {
            	return 1.0 - Math.log1p(-x);
            }
            
            def code(x, y):
            	return 1.0 - math.log1p(-x)
            
            function code(x, y)
            	return Float64(1.0 - log1p(Float64(-x)))
            end
            
            code[x_, y_] := N[(1.0 - N[Log[1 + (-x)], $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            1 - \mathsf{log1p}\left(-x\right)
            \end{array}
            
            Derivation
            1. Initial program 74.5%

              \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
            2. Add Preprocessing
            3. Taylor expanded in y around 0

              \[\leadsto 1 - \color{blue}{\log \left(1 - x\right)} \]
            4. Step-by-step derivation
              1. sub-negN/A

                \[\leadsto 1 - \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(x\right)\right)\right)} \]
              2. mul-1-negN/A

                \[\leadsto 1 - \log \left(1 + \color{blue}{-1 \cdot x}\right) \]
              3. lower-log1p.f64N/A

                \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-1 \cdot x\right)} \]
              4. mul-1-negN/A

                \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\mathsf{neg}\left(x\right)}\right) \]
              5. lower-neg.f6463.4

                \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{-x}\right) \]
            5. Applied rewrites63.4%

              \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-x\right)} \]
            6. Add Preprocessing

            Alternative 8: 43.4% accurate, 20.7× speedup?

            \[\begin{array}{l} \\ 1 - \left(-x\right) \end{array} \]
            (FPCore (x y) :precision binary64 (- 1.0 (- x)))
            double code(double x, double y) {
            	return 1.0 - -x;
            }
            
            real(8) function code(x, y)
                real(8), intent (in) :: x
                real(8), intent (in) :: y
                code = 1.0d0 - -x
            end function
            
            public static double code(double x, double y) {
            	return 1.0 - -x;
            }
            
            def code(x, y):
            	return 1.0 - -x
            
            function code(x, y)
            	return Float64(1.0 - Float64(-x))
            end
            
            function tmp = code(x, y)
            	tmp = 1.0 - -x;
            end
            
            code[x_, y_] := N[(1.0 - (-x)), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            1 - \left(-x\right)
            \end{array}
            
            Derivation
            1. Initial program 74.5%

              \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
            2. Add Preprocessing
            3. Taylor expanded in y around 0

              \[\leadsto 1 - \color{blue}{\log \left(1 - x\right)} \]
            4. Step-by-step derivation
              1. sub-negN/A

                \[\leadsto 1 - \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(x\right)\right)\right)} \]
              2. mul-1-negN/A

                \[\leadsto 1 - \log \left(1 + \color{blue}{-1 \cdot x}\right) \]
              3. lower-log1p.f64N/A

                \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-1 \cdot x\right)} \]
              4. mul-1-negN/A

                \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\mathsf{neg}\left(x\right)}\right) \]
              5. lower-neg.f6463.4

                \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{-x}\right) \]
            5. Applied rewrites63.4%

              \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-x\right)} \]
            6. Taylor expanded in x around 0

              \[\leadsto 1 - -1 \cdot \color{blue}{x} \]
            7. Step-by-step derivation
              1. Applied rewrites41.8%

                \[\leadsto 1 - \left(-x\right) \]
              2. Add Preprocessing

              Alternative 9: 42.1% accurate, 31.0× speedup?

              \[\begin{array}{l} \\ 1 - x \end{array} \]
              (FPCore (x y) :precision binary64 (- 1.0 x))
              double code(double x, double y) {
              	return 1.0 - x;
              }
              
              real(8) function code(x, y)
                  real(8), intent (in) :: x
                  real(8), intent (in) :: y
                  code = 1.0d0 - x
              end function
              
              public static double code(double x, double y) {
              	return 1.0 - x;
              }
              
              def code(x, y):
              	return 1.0 - x
              
              function code(x, y)
              	return Float64(1.0 - x)
              end
              
              function tmp = code(x, y)
              	tmp = 1.0 - x;
              end
              
              code[x_, y_] := N[(1.0 - x), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              1 - x
              \end{array}
              
              Derivation
              1. Initial program 74.5%

                \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
              2. Add Preprocessing
              3. Taylor expanded in y around 0

                \[\leadsto 1 - \color{blue}{\log \left(1 - x\right)} \]
              4. Step-by-step derivation
                1. sub-negN/A

                  \[\leadsto 1 - \log \color{blue}{\left(1 + \left(\mathsf{neg}\left(x\right)\right)\right)} \]
                2. mul-1-negN/A

                  \[\leadsto 1 - \log \left(1 + \color{blue}{-1 \cdot x}\right) \]
                3. lower-log1p.f64N/A

                  \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-1 \cdot x\right)} \]
                4. mul-1-negN/A

                  \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\mathsf{neg}\left(x\right)}\right) \]
                5. lower-neg.f6463.4

                  \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{-x}\right) \]
              5. Applied rewrites63.4%

                \[\leadsto 1 - \color{blue}{\mathsf{log1p}\left(-x\right)} \]
              6. Taylor expanded in x around 0

                \[\leadsto 1 - -1 \cdot \color{blue}{x} \]
              7. Step-by-step derivation
                1. Applied rewrites41.8%

                  \[\leadsto 1 - \left(-x\right) \]
                2. Step-by-step derivation
                  1. Applied rewrites41.7%

                    \[\leadsto 1 - \frac{0 - x \cdot x}{0 + \color{blue}{x}} \]
                  2. Step-by-step derivation
                    1. Applied rewrites40.4%

                      \[\leadsto 1 - x \]
                    2. Add Preprocessing

                    Developer Target 1: 99.8% accurate, 0.5× speedup?

                    \[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 - \log \left(\frac{x}{y \cdot y} - \left(\frac{1}{y} - \frac{x}{y}\right)\right)\\ \mathbf{if}\;y < -81284752.61947241:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y < 3.0094271212461764 \cdot 10^{+25}:\\ \;\;\;\;\log \left(\frac{e^{1}}{1 - \frac{x - y}{1 - y}}\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
                    (FPCore (x y)
                     :precision binary64
                     (let* ((t_0 (- 1.0 (log (- (/ x (* y y)) (- (/ 1.0 y) (/ x y)))))))
                       (if (< y -81284752.61947241)
                         t_0
                         (if (< y 3.0094271212461764e+25)
                           (log (/ (exp 1.0) (- 1.0 (/ (- x y) (- 1.0 y)))))
                           t_0))))
                    double code(double x, double y) {
                    	double t_0 = 1.0 - log(((x / (y * y)) - ((1.0 / y) - (x / y))));
                    	double tmp;
                    	if (y < -81284752.61947241) {
                    		tmp = t_0;
                    	} else if (y < 3.0094271212461764e+25) {
                    		tmp = log((exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))));
                    	} 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) :: tmp
                        t_0 = 1.0d0 - log(((x / (y * y)) - ((1.0d0 / y) - (x / y))))
                        if (y < (-81284752.61947241d0)) then
                            tmp = t_0
                        else if (y < 3.0094271212461764d+25) then
                            tmp = log((exp(1.0d0) / (1.0d0 - ((x - y) / (1.0d0 - y)))))
                        else
                            tmp = t_0
                        end if
                        code = tmp
                    end function
                    
                    public static double code(double x, double y) {
                    	double t_0 = 1.0 - Math.log(((x / (y * y)) - ((1.0 / y) - (x / y))));
                    	double tmp;
                    	if (y < -81284752.61947241) {
                    		tmp = t_0;
                    	} else if (y < 3.0094271212461764e+25) {
                    		tmp = Math.log((Math.exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))));
                    	} else {
                    		tmp = t_0;
                    	}
                    	return tmp;
                    }
                    
                    def code(x, y):
                    	t_0 = 1.0 - math.log(((x / (y * y)) - ((1.0 / y) - (x / y))))
                    	tmp = 0
                    	if y < -81284752.61947241:
                    		tmp = t_0
                    	elif y < 3.0094271212461764e+25:
                    		tmp = math.log((math.exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))))
                    	else:
                    		tmp = t_0
                    	return tmp
                    
                    function code(x, y)
                    	t_0 = Float64(1.0 - log(Float64(Float64(x / Float64(y * y)) - Float64(Float64(1.0 / y) - Float64(x / y)))))
                    	tmp = 0.0
                    	if (y < -81284752.61947241)
                    		tmp = t_0;
                    	elseif (y < 3.0094271212461764e+25)
                    		tmp = log(Float64(exp(1.0) / Float64(1.0 - Float64(Float64(x - y) / Float64(1.0 - y)))));
                    	else
                    		tmp = t_0;
                    	end
                    	return tmp
                    end
                    
                    function tmp_2 = code(x, y)
                    	t_0 = 1.0 - log(((x / (y * y)) - ((1.0 / y) - (x / y))));
                    	tmp = 0.0;
                    	if (y < -81284752.61947241)
                    		tmp = t_0;
                    	elseif (y < 3.0094271212461764e+25)
                    		tmp = log((exp(1.0) / (1.0 - ((x - y) / (1.0 - y)))));
                    	else
                    		tmp = t_0;
                    	end
                    	tmp_2 = tmp;
                    end
                    
                    code[x_, y_] := Block[{t$95$0 = N[(1.0 - N[Log[N[(N[(x / N[(y * y), $MachinePrecision]), $MachinePrecision] - N[(N[(1.0 / y), $MachinePrecision] - N[(x / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[Less[y, -81284752.61947241], t$95$0, If[Less[y, 3.0094271212461764e+25], N[Log[N[(N[Exp[1.0], $MachinePrecision] / N[(1.0 - N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], t$95$0]]]
                    
                    \begin{array}{l}
                    
                    \\
                    \begin{array}{l}
                    t_0 := 1 - \log \left(\frac{x}{y \cdot y} - \left(\frac{1}{y} - \frac{x}{y}\right)\right)\\
                    \mathbf{if}\;y < -81284752.61947241:\\
                    \;\;\;\;t\_0\\
                    
                    \mathbf{elif}\;y < 3.0094271212461764 \cdot 10^{+25}:\\
                    \;\;\;\;\log \left(\frac{e^{1}}{1 - \frac{x - y}{1 - y}}\right)\\
                    
                    \mathbf{else}:\\
                    \;\;\;\;t\_0\\
                    
                    
                    \end{array}
                    \end{array}
                    

                    Reproduce

                    ?
                    herbie shell --seed 2024294 
                    (FPCore (x y)
                      :name "Numeric.SpecFunctions:invIncompleteGamma from math-functions-0.1.5.2, B"
                      :precision binary64
                    
                      :alt
                      (! :herbie-platform default (if (< y -8128475261947241/100000000) (- 1 (log (- (/ x (* y y)) (- (/ 1 y) (/ x y))))) (if (< y 30094271212461764000000000) (log (/ (exp 1) (- 1 (/ (- x y) (- 1 y))))) (- 1 (log (- (/ x (* y y)) (- (/ 1 y) (/ x y))))))))
                    
                      (- 1.0 (log (- 1.0 (/ (- x y) (- 1.0 y))))))