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

Percentage Accurate: 72.4% → 99.8%
Time: 15.3s
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: 72.4% 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, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.999995:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y \cdot 3}{x \cdot 3 + -3}\right)\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (if (<= (/ (- x y) (- 1.0 y)) 0.999995)
   (- 1.0 (log1p (/ (- x y) (+ y -1.0))))
   (+ 1.0 (log (/ (* y 3.0) (+ (* x 3.0) -3.0))))))
double code(double x, double y) {
	double tmp;
	if (((x - y) / (1.0 - y)) <= 0.999995) {
		tmp = 1.0 - log1p(((x - y) / (y + -1.0)));
	} else {
		tmp = 1.0 + log(((y * 3.0) / ((x * 3.0) + -3.0)));
	}
	return tmp;
}
public static double code(double x, double y) {
	double tmp;
	if (((x - y) / (1.0 - y)) <= 0.999995) {
		tmp = 1.0 - Math.log1p(((x - y) / (y + -1.0)));
	} else {
		tmp = 1.0 + Math.log(((y * 3.0) / ((x * 3.0) + -3.0)));
	}
	return tmp;
}
def code(x, y):
	tmp = 0
	if ((x - y) / (1.0 - y)) <= 0.999995:
		tmp = 1.0 - math.log1p(((x - y) / (y + -1.0)))
	else:
		tmp = 1.0 + math.log(((y * 3.0) / ((x * 3.0) + -3.0)))
	return tmp
function code(x, y)
	tmp = 0.0
	if (Float64(Float64(x - y) / Float64(1.0 - y)) <= 0.999995)
		tmp = Float64(1.0 - log1p(Float64(Float64(x - y) / Float64(y + -1.0))));
	else
		tmp = Float64(1.0 + log(Float64(Float64(y * 3.0) / Float64(Float64(x * 3.0) + -3.0))));
	end
	return tmp
end
code[x_, y_] := If[LessEqual[N[(N[(x - y), $MachinePrecision] / N[(1.0 - y), $MachinePrecision]), $MachinePrecision], 0.999995], N[(1.0 - N[Log[1 + N[(N[(x - y), $MachinePrecision] / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(1.0 + N[Log[N[(N[(y * 3.0), $MachinePrecision] / N[(N[(x * 3.0), $MachinePrecision] + -3.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;\frac{x - y}{1 - y} \leq 0.999995:\\
\;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\

\mathbf{else}:\\
\;\;\;\;1 + \log \left(\frac{y \cdot 3}{x \cdot 3 + -3}\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y)) < 0.99999499999999997

    1. Initial program 99.8%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6499.9%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified99.9%

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

    if 0.99999499999999997 < (/.f64 (-.f64 x y) (-.f64 #s(literal 1 binary64) y))

    1. Initial program 7.1%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f647.1%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified7.1%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{\frac{y + -1}{x - y}}\right)\right)\right) \]
      2. associate-/r/N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\frac{1}{y + -1}\right), \left(x - y\right)\right)\right)\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \left(y + -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      6. --lowering--.f647.8%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \mathsf{\_.f64}\left(x, y\right)\right)\right)\right) \]
    6. Applied egg-rr7.8%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{1}{y + -1} \cdot \left(x - y\right)}\right) \]
    7. Step-by-step derivation
      1. flip3-+N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}\right)\right) \]
      2. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{1}{\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}}\right)\right) \]
      3. log-recN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{neg}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
      4. neg-lowering-neg.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right) \]
      5. log-lowering-log.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
    8. Applied egg-rr4.9%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(3 \cdot \frac{y}{\left(x + 2 \cdot x\right) - 3}\right)}\right)\right)\right) \]
    10. Step-by-step derivation
      1. associate-*r/N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\left(\frac{3 \cdot y}{\left(x + 2 \cdot x\right) - 3}\right)\right)\right)\right) \]
      2. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(3 \cdot y\right), \left(\left(x + 2 \cdot x\right) - 3\right)\right)\right)\right)\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(3, y\right), \left(\left(x + 2 \cdot x\right) - 3\right)\right)\right)\right)\right) \]
      4. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(3, y\right), \left(\left(x + 2 \cdot x\right) + \left(\mathsf{neg}\left(3\right)\right)\right)\right)\right)\right)\right) \]
      5. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(3, y\right), \left(\left(x + 2 \cdot x\right) + -3\right)\right)\right)\right)\right) \]
      6. +-lowering-+.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(3, y\right), \mathsf{+.f64}\left(\left(x + 2 \cdot x\right), -3\right)\right)\right)\right)\right) \]
      7. distribute-rgt1-inN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(3, y\right), \mathsf{+.f64}\left(\left(\left(2 + 1\right) \cdot x\right), -3\right)\right)\right)\right)\right) \]
      8. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(3, y\right), \mathsf{+.f64}\left(\left(3 \cdot x\right), -3\right)\right)\right)\right)\right) \]
      9. *-lowering-*.f6499.0%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{*.f64}\left(3, y\right), \mathsf{+.f64}\left(\mathsf{*.f64}\left(3, x\right), -3\right)\right)\right)\right)\right) \]
    11. Simplified99.0%

      \[\leadsto 1 - \left(-\log \color{blue}{\left(\frac{3 \cdot y}{3 \cdot x + -3}\right)}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{x - y}{1 - y} \leq 0.999995:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y \cdot 3}{x \cdot 3 + -3}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 98.2% accurate, 0.9× speedup?

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

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

\mathbf{elif}\;x \leq 1:\\
\;\;\;\;1 + \log \left(y \cdot \left(-1 + \frac{1}{y}\right)\right)\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


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

    1. Initial program 74.4%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6474.4%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified74.4%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{\frac{y + -1}{x - y}}\right)\right)\right) \]
      2. associate-/r/N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\frac{1}{y + -1}\right), \left(x - y\right)\right)\right)\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \left(y + -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      6. --lowering--.f6474.4%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \mathsf{\_.f64}\left(x, y\right)\right)\right)\right) \]
    6. Applied egg-rr74.4%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{1}{y + -1} \cdot \left(x - y\right)}\right) \]
    7. Step-by-step derivation
      1. flip3-+N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}\right)\right) \]
      2. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{1}{\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}}\right)\right) \]
      3. log-recN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{neg}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
      4. neg-lowering-neg.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right) \]
      5. log-lowering-log.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
    8. Applied egg-rr27.4%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(\frac{y - 1}{x}\right)}\right)\right)\right) \]
    10. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y - 1\right), x\right)\right)\right)\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right), x\right)\right)\right)\right) \]
      3. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + -1\right), x\right)\right)\right)\right) \]
      4. +-lowering-+.f6498.9%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(y, -1\right), x\right)\right)\right)\right) \]
    11. Simplified98.9%

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

    if -1 < x < 1

    1. Initial program 65.9%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6465.9%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified65.9%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{\frac{y + -1}{x - y}}\right)\right)\right) \]
      2. associate-/r/N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\frac{1}{y + -1}\right), \left(x - y\right)\right)\right)\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \left(y + -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      6. --lowering--.f6466.3%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \mathsf{\_.f64}\left(x, y\right)\right)\right)\right) \]
    6. Applied egg-rr66.3%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{1}{y + -1} \cdot \left(x - y\right)}\right) \]
    7. Step-by-step derivation
      1. flip3-+N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}\right)\right) \]
      2. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{1}{\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}}\right)\right) \]
      3. log-recN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{neg}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
      4. neg-lowering-neg.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right) \]
      5. log-lowering-log.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
    8. Applied egg-rr65.4%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(-1 \cdot \left(y \cdot \left(-1 \cdot \frac{\left(-2 \cdot \frac{x}{\left(x + 2 \cdot x\right) - 3} + \left(-1 \cdot \frac{x - 1}{\left(x + 2 \cdot x\right) - 3} + 2 \cdot \frac{1}{\left(x + 2 \cdot x\right) - 3}\right)\right) - -3 \cdot \frac{\left(2 \cdot {x}^{2} + {x}^{2}\right) - \left(3 + 3 \cdot \left(\left(x + 2 \cdot x\right) - 3\right)\right)}{{\left(\left(x + 2 \cdot x\right) - 3\right)}^{2}}}{y} - 3 \cdot \frac{1}{\left(x + 2 \cdot x\right) - 3}\right)\right)\right)}\right)\right)\right) \]
    10. Simplified99.8%

      \[\leadsto 1 - \left(-\log \color{blue}{\left(\left(-y\right) \cdot \left(\left(-\frac{\frac{x \cdot -2}{3 \cdot x + -3} + \left(\left(\frac{-1 \cdot \left(x + -1\right)}{3 \cdot x + -3} + \frac{2}{3 \cdot x + -3}\right) - -3 \cdot \frac{\left(3 \cdot \left(x \cdot x\right) - 3\right) - 3 \cdot \left(3 \cdot x + -3\right)}{\left(3 \cdot x + -3\right) \cdot \left(3 \cdot x + -3\right)}\right)}{y}\right) - \frac{3}{3 \cdot x + -3}\right)\right)}\right) \]
    11. Taylor expanded in x around 0

      \[\leadsto \color{blue}{1 + \log \left(-1 \cdot \left(y \cdot \left(1 - \frac{1}{y}\right)\right)\right)} \]
    12. Step-by-step derivation
      1. +-lowering-+.f64N/A

        \[\leadsto \mathsf{+.f64}\left(1, \color{blue}{\log \left(-1 \cdot \left(y \cdot \left(1 - \frac{1}{y}\right)\right)\right)}\right) \]
      2. log-lowering-log.f64N/A

        \[\leadsto \mathsf{+.f64}\left(1, \mathsf{log.f64}\left(\left(-1 \cdot \left(y \cdot \left(1 - \frac{1}{y}\right)\right)\right)\right)\right) \]
      3. mul-1-negN/A

        \[\leadsto \mathsf{+.f64}\left(1, \mathsf{log.f64}\left(\left(\mathsf{neg}\left(y \cdot \left(1 - \frac{1}{y}\right)\right)\right)\right)\right) \]
      4. neg-sub0N/A

        \[\leadsto \mathsf{+.f64}\left(1, \mathsf{log.f64}\left(\left(0 - y \cdot \left(1 - \frac{1}{y}\right)\right)\right)\right) \]
      5. --lowering--.f64N/A

        \[\leadsto \mathsf{+.f64}\left(1, \mathsf{log.f64}\left(\mathsf{\_.f64}\left(0, \left(y \cdot \left(1 - \frac{1}{y}\right)\right)\right)\right)\right) \]
      6. *-lowering-*.f64N/A

        \[\leadsto \mathsf{+.f64}\left(1, \mathsf{log.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{*.f64}\left(y, \left(1 - \frac{1}{y}\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{+.f64}\left(1, \mathsf{log.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{*.f64}\left(y, \mathsf{\_.f64}\left(1, \left(\frac{1}{y}\right)\right)\right)\right)\right)\right) \]
      8. /-lowering-/.f6498.8%

        \[\leadsto \mathsf{+.f64}\left(1, \mathsf{log.f64}\left(\mathsf{\_.f64}\left(0, \mathsf{*.f64}\left(y, \mathsf{\_.f64}\left(1, \mathsf{/.f64}\left(1, y\right)\right)\right)\right)\right)\right) \]
    13. Simplified98.8%

      \[\leadsto \color{blue}{1 + \log \left(0 - y \cdot \left(1 - \frac{1}{y}\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification98.9%

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

Alternative 3: 81.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \log \left(\frac{y}{x}\right)\\ \mathbf{if}\;y \leq -2.36 \cdot 10^{+27}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y \leq 2 \cdot 10^{+15}:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 1.0 (log (/ y x)))))
   (if (<= y -2.36e+27)
     t_0
     (if (<= y 2e+15) (- 1.0 (log1p (/ (- x y) (+ y -1.0)))) t_0))))
double code(double x, double y) {
	double t_0 = 1.0 + log((y / x));
	double tmp;
	if (y <= -2.36e+27) {
		tmp = t_0;
	} else if (y <= 2e+15) {
		tmp = 1.0 - log1p(((x - y) / (y + -1.0)));
	} else {
		tmp = t_0;
	}
	return tmp;
}
public static double code(double x, double y) {
	double t_0 = 1.0 + Math.log((y / x));
	double tmp;
	if (y <= -2.36e+27) {
		tmp = t_0;
	} else if (y <= 2e+15) {
		tmp = 1.0 - Math.log1p(((x - y) / (y + -1.0)));
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 + math.log((y / x))
	tmp = 0
	if y <= -2.36e+27:
		tmp = t_0
	elif y <= 2e+15:
		tmp = 1.0 - math.log1p(((x - y) / (y + -1.0)))
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 + log(Float64(y / x)))
	tmp = 0.0
	if (y <= -2.36e+27)
		tmp = t_0;
	elseif (y <= 2e+15)
		tmp = Float64(1.0 - log1p(Float64(Float64(x - y) / Float64(y + -1.0))));
	else
		tmp = t_0;
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[Log[N[(y / x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -2.36e+27], t$95$0, If[LessEqual[y, 2e+15], N[(1.0 - N[Log[1 + N[(N[(x - y), $MachinePrecision] / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], t$95$0]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \log \left(\frac{y}{x}\right)\\
\mathbf{if}\;y \leq -2.36 \cdot 10^{+27}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y \leq 2 \cdot 10^{+15}:\\
\;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -2.36000000000000012e27 or 2e15 < y

    1. Initial program 24.5%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6424.6%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified24.6%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{\frac{y + -1}{x - y}}\right)\right)\right) \]
      2. associate-/r/N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\frac{1}{y + -1}\right), \left(x - y\right)\right)\right)\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \left(y + -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      6. --lowering--.f6425.2%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \mathsf{\_.f64}\left(x, y\right)\right)\right)\right) \]
    6. Applied egg-rr25.2%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{1}{y + -1} \cdot \left(x - y\right)}\right) \]
    7. Step-by-step derivation
      1. flip3-+N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}\right)\right) \]
      2. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{1}{\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}}\right)\right) \]
      3. log-recN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{neg}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
      4. neg-lowering-neg.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right) \]
      5. log-lowering-log.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
    8. Applied egg-rr5.6%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(\frac{y - 1}{x}\right)}\right)\right)\right) \]
    10. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y - 1\right), x\right)\right)\right)\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right), x\right)\right)\right)\right) \]
      3. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + -1\right), x\right)\right)\right)\right) \]
      4. +-lowering-+.f6449.8%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(y, -1\right), x\right)\right)\right)\right) \]
    11. Simplified49.8%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(\frac{y}{x}\right)}\right)\right)\right) \]
    13. Step-by-step derivation
      1. /-lowering-/.f6449.8%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(y, x\right)\right)\right)\right) \]
    14. Simplified49.8%

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

    if -2.36000000000000012e27 < y < 2e15

    1. Initial program 97.1%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6497.2%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified97.2%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification78.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -2.36 \cdot 10^{+27}:\\ \;\;\;\;1 + \log \left(\frac{y}{x}\right)\\ \mathbf{elif}\;y \leq 2 \cdot 10^{+15}:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 80.0% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \log \left(\frac{y + -1}{x}\right)\\ \mathbf{if}\;x \leq -0.116:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;x \leq 1:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{y}{1 - y}\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 1.0 (log (/ (+ y -1.0) x)))))
   (if (<= x -0.116) t_0 (if (<= x 1.0) (- 1.0 (log1p (/ y (- 1.0 y)))) t_0))))
double code(double x, double y) {
	double t_0 = 1.0 + log(((y + -1.0) / x));
	double tmp;
	if (x <= -0.116) {
		tmp = t_0;
	} else if (x <= 1.0) {
		tmp = 1.0 - log1p((y / (1.0 - y)));
	} else {
		tmp = t_0;
	}
	return tmp;
}
public static double code(double x, double y) {
	double t_0 = 1.0 + Math.log(((y + -1.0) / x));
	double tmp;
	if (x <= -0.116) {
		tmp = t_0;
	} else if (x <= 1.0) {
		tmp = 1.0 - Math.log1p((y / (1.0 - y)));
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 + math.log(((y + -1.0) / x))
	tmp = 0
	if x <= -0.116:
		tmp = t_0
	elif x <= 1.0:
		tmp = 1.0 - math.log1p((y / (1.0 - y)))
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 + log(Float64(Float64(y + -1.0) / x)))
	tmp = 0.0
	if (x <= -0.116)
		tmp = t_0;
	elseif (x <= 1.0)
		tmp = Float64(1.0 - log1p(Float64(y / Float64(1.0 - y))));
	else
		tmp = t_0;
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[Log[N[(N[(y + -1.0), $MachinePrecision] / x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, -0.116], t$95$0, If[LessEqual[x, 1.0], N[(1.0 - N[Log[1 + N[(y / N[(1.0 - y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], t$95$0]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \log \left(\frac{y + -1}{x}\right)\\
\mathbf{if}\;x \leq -0.116:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;x \leq 1:\\
\;\;\;\;1 - \mathsf{log1p}\left(\frac{y}{1 - y}\right)\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -0.116000000000000006 or 1 < x

    1. Initial program 74.4%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6474.4%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified74.4%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{\frac{y + -1}{x - y}}\right)\right)\right) \]
      2. associate-/r/N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\frac{1}{y + -1}\right), \left(x - y\right)\right)\right)\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \left(y + -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      6. --lowering--.f6474.4%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \mathsf{\_.f64}\left(x, y\right)\right)\right)\right) \]
    6. Applied egg-rr74.4%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{1}{y + -1} \cdot \left(x - y\right)}\right) \]
    7. Step-by-step derivation
      1. flip3-+N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}\right)\right) \]
      2. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{1}{\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}}\right)\right) \]
      3. log-recN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{neg}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
      4. neg-lowering-neg.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right) \]
      5. log-lowering-log.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
    8. Applied egg-rr27.4%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(\frac{y - 1}{x}\right)}\right)\right)\right) \]
    10. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y - 1\right), x\right)\right)\right)\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right), x\right)\right)\right)\right) \]
      3. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + -1\right), x\right)\right)\right)\right) \]
      4. +-lowering-+.f6498.9%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(y, -1\right), x\right)\right)\right)\right) \]
    11. Simplified98.9%

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

    if -0.116000000000000006 < x < 1

    1. Initial program 65.9%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6465.9%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified65.9%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0

      \[\leadsto \color{blue}{1 - \log \left(1 - \frac{y}{y - 1}\right)} \]
    6. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{y}{y - 1}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{y}{y - 1}\right)\right)\right)\right) \]
      3. mul-1-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + -1 \cdot \frac{y}{y - 1}\right)\right) \]
      4. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(-1 \cdot \frac{y}{y - 1}\right)\right)\right) \]
      5. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(-1 \cdot \frac{y}{y - 1}\right)\right)\right) \]
      6. mul-1-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{y}{y - 1}\right)\right)\right)\right) \]
      7. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{y}{\mathsf{neg}\left(\left(y - 1\right)\right)}\right)\right)\right) \]
      8. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \left(\mathsf{neg}\left(\left(y - 1\right)\right)\right)\right)\right)\right) \]
      9. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \left(\mathsf{neg}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right)\right)\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \left(\mathsf{neg}\left(\left(y + -1\right)\right)\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \left(\mathsf{neg}\left(\left(-1 + y\right)\right)\right)\right)\right)\right) \]
      12. distribute-neg-inN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \left(\left(\mathsf{neg}\left(-1\right)\right) + \left(\mathsf{neg}\left(y\right)\right)\right)\right)\right)\right) \]
      13. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)\right)\right)\right) \]
      14. rgt-mult-inverseN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \left(y \cdot \frac{1}{y} + \left(\mathsf{neg}\left(y\right)\right)\right)\right)\right)\right) \]
      15. unsub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \left(y \cdot \frac{1}{y} - y\right)\right)\right)\right) \]
      16. rgt-mult-inverseN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \left(1 - y\right)\right)\right)\right) \]
      17. --lowering--.f6465.1%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(y, \mathsf{\_.f64}\left(1, y\right)\right)\right)\right) \]
    7. Simplified65.1%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{y}{1 - y}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification77.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -0.116:\\ \;\;\;\;1 + \log \left(\frac{y + -1}{x}\right)\\ \mathbf{elif}\;x \leq 1:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{y}{1 - y}\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y + -1}{x}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 80.1% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \log \left(\frac{y}{x}\right)\\ \mathbf{if}\;y \leq -1.5 \cdot 10^{+27}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y \leq 9600000000000:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 1.0 (log (/ y x)))))
   (if (<= y -1.5e+27)
     t_0
     (if (<= y 9600000000000.0) (- 1.0 (log1p (/ x (+ y -1.0)))) t_0))))
double code(double x, double y) {
	double t_0 = 1.0 + log((y / x));
	double tmp;
	if (y <= -1.5e+27) {
		tmp = t_0;
	} else if (y <= 9600000000000.0) {
		tmp = 1.0 - log1p((x / (y + -1.0)));
	} else {
		tmp = t_0;
	}
	return tmp;
}
public static double code(double x, double y) {
	double t_0 = 1.0 + Math.log((y / x));
	double tmp;
	if (y <= -1.5e+27) {
		tmp = t_0;
	} else if (y <= 9600000000000.0) {
		tmp = 1.0 - Math.log1p((x / (y + -1.0)));
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 + math.log((y / x))
	tmp = 0
	if y <= -1.5e+27:
		tmp = t_0
	elif y <= 9600000000000.0:
		tmp = 1.0 - math.log1p((x / (y + -1.0)))
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 + log(Float64(y / x)))
	tmp = 0.0
	if (y <= -1.5e+27)
		tmp = t_0;
	elseif (y <= 9600000000000.0)
		tmp = Float64(1.0 - log1p(Float64(x / Float64(y + -1.0))));
	else
		tmp = t_0;
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[Log[N[(y / x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -1.5e+27], t$95$0, If[LessEqual[y, 9600000000000.0], N[(1.0 - N[Log[1 + N[(x / N[(y + -1.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], t$95$0]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \log \left(\frac{y}{x}\right)\\
\mathbf{if}\;y \leq -1.5 \cdot 10^{+27}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y \leq 9600000000000:\\
\;\;\;\;1 - \mathsf{log1p}\left(\frac{x}{y + -1}\right)\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.49999999999999988e27 or 9.6e12 < y

    1. Initial program 25.3%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6425.3%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified25.3%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{\frac{y + -1}{x - y}}\right)\right)\right) \]
      2. associate-/r/N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\frac{1}{y + -1}\right), \left(x - y\right)\right)\right)\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \left(y + -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      6. --lowering--.f6426.0%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \mathsf{\_.f64}\left(x, y\right)\right)\right)\right) \]
    6. Applied egg-rr26.0%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{1}{y + -1} \cdot \left(x - y\right)}\right) \]
    7. Step-by-step derivation
      1. flip3-+N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}\right)\right) \]
      2. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{1}{\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}}\right)\right) \]
      3. log-recN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{neg}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
      4. neg-lowering-neg.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right) \]
      5. log-lowering-log.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
    8. Applied egg-rr6.6%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(\frac{y - 1}{x}\right)}\right)\right)\right) \]
    10. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y - 1\right), x\right)\right)\right)\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right), x\right)\right)\right)\right) \]
      3. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + -1\right), x\right)\right)\right)\right) \]
      4. +-lowering-+.f6450.3%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(y, -1\right), x\right)\right)\right)\right) \]
    11. Simplified50.3%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(\frac{y}{x}\right)}\right)\right)\right) \]
    13. Step-by-step derivation
      1. /-lowering-/.f6450.3%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(y, x\right)\right)\right)\right) \]
    14. Simplified50.3%

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

    if -1.49999999999999988e27 < y < 9.6e12

    1. Initial program 97.1%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6497.1%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified97.1%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in x around inf

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\color{blue}{\left(\frac{x}{y - 1}\right)}\right)\right) \]
    6. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(x, \left(y - 1\right)\right)\right)\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(x, \left(y + \left(\mathsf{neg}\left(1\right)\right)\right)\right)\right)\right) \]
      3. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(x, \left(y + -1\right)\right)\right)\right) \]
      4. +-lowering-+.f6492.2%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(x, \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    7. Simplified92.2%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{x}{y + -1}}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification75.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.5 \cdot 10^{+27}:\\ \;\;\;\;1 + \log \left(\frac{y}{x}\right)\\ \mathbf{elif}\;y \leq 9600000000000:\\ \;\;\;\;1 - \mathsf{log1p}\left(\frac{x}{y + -1}\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 79.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 1 + \log \left(\frac{y}{x}\right)\\ \mathbf{if}\;y \leq -1.3 \cdot 10^{+18}:\\ \;\;\;\;t\_0\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;1 - \mathsf{log1p}\left(0 - x\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x y)
 :precision binary64
 (let* ((t_0 (+ 1.0 (log (/ y x)))))
   (if (<= y -1.3e+18) t_0 (if (<= y 1.0) (- 1.0 (log1p (- 0.0 x))) t_0))))
double code(double x, double y) {
	double t_0 = 1.0 + log((y / x));
	double tmp;
	if (y <= -1.3e+18) {
		tmp = t_0;
	} else if (y <= 1.0) {
		tmp = 1.0 - log1p((0.0 - x));
	} else {
		tmp = t_0;
	}
	return tmp;
}
public static double code(double x, double y) {
	double t_0 = 1.0 + Math.log((y / x));
	double tmp;
	if (y <= -1.3e+18) {
		tmp = t_0;
	} else if (y <= 1.0) {
		tmp = 1.0 - Math.log1p((0.0 - x));
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x, y):
	t_0 = 1.0 + math.log((y / x))
	tmp = 0
	if y <= -1.3e+18:
		tmp = t_0
	elif y <= 1.0:
		tmp = 1.0 - math.log1p((0.0 - x))
	else:
		tmp = t_0
	return tmp
function code(x, y)
	t_0 = Float64(1.0 + log(Float64(y / x)))
	tmp = 0.0
	if (y <= -1.3e+18)
		tmp = t_0;
	elseif (y <= 1.0)
		tmp = Float64(1.0 - log1p(Float64(0.0 - x)));
	else
		tmp = t_0;
	end
	return tmp
end
code[x_, y_] := Block[{t$95$0 = N[(1.0 + N[Log[N[(y / x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[y, -1.3e+18], t$95$0, If[LessEqual[y, 1.0], N[(1.0 - N[Log[1 + N[(0.0 - x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], t$95$0]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 1 + \log \left(\frac{y}{x}\right)\\
\mathbf{if}\;y \leq -1.3 \cdot 10^{+18}:\\
\;\;\;\;t\_0\\

\mathbf{elif}\;y \leq 1:\\
\;\;\;\;1 - \mathsf{log1p}\left(0 - x\right)\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -1.3e18 or 1 < y

    1. Initial program 26.5%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6426.5%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified26.5%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{\frac{y + -1}{x - y}}\right)\right)\right) \]
      2. associate-/r/N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)\right) \]
      3. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\frac{1}{y + -1}\right), \left(x - y\right)\right)\right)\right) \]
      4. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \left(y + -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      5. +-lowering-+.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \left(x - y\right)\right)\right)\right) \]
      6. --lowering--.f6427.2%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{/.f64}\left(1, \mathsf{+.f64}\left(y, -1\right)\right), \mathsf{\_.f64}\left(x, y\right)\right)\right)\right) \]
    6. Applied egg-rr27.2%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\frac{1}{y + -1} \cdot \left(x - y\right)}\right) \]
    7. Step-by-step derivation
      1. flip3-+N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}\right)\right) \]
      2. clear-numN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(\frac{1}{\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}}\right)\right) \]
      3. log-recN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{neg}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
      4. neg-lowering-neg.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\log \left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right) \]
      5. log-lowering-log.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\left(\frac{1 \cdot 1 + \left(\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right) - 1 \cdot \left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)\right)}{{1}^{3} + {\left(\frac{1}{y + -1} \cdot \left(x - y\right)\right)}^{3}}\right)\right)\right)\right) \]
    8. Applied egg-rr6.4%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(\frac{y - 1}{x}\right)}\right)\right)\right) \]
    10. Step-by-step derivation
      1. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y - 1\right), x\right)\right)\right)\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right), x\right)\right)\right)\right) \]
      3. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\left(y + -1\right), x\right)\right)\right)\right) \]
      4. +-lowering-+.f6450.8%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(\mathsf{+.f64}\left(y, -1\right), x\right)\right)\right)\right) \]
    11. Simplified50.8%

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

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\color{blue}{\left(\frac{y}{x}\right)}\right)\right)\right) \]
    13. Step-by-step derivation
      1. /-lowering-/.f6450.4%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{neg.f64}\left(\mathsf{log.f64}\left(\mathsf{/.f64}\left(y, x\right)\right)\right)\right) \]
    14. Simplified50.4%

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

    if -1.3e18 < y < 1

    1. Initial program 97.7%

      \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
    2. Step-by-step derivation
      1. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
      2. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      3. log1p-defineN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      4. log1p-lowering-log1p.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
      5. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
      6. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      7. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
      8. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
      9. associate--r-N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
      10. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
      11. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
      12. +-lowering-+.f6497.7%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
    3. Simplified97.7%

      \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in x around -inf

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\color{blue}{\left(-1 \cdot \left(x \cdot \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)}\right)\right) \]
    6. Step-by-step derivation
      1. associate-*r*N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\left(-1 \cdot x\right) \cdot \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
      2. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(-1 \cdot x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
      3. mul-1-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\mathsf{neg}\left(x\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
      4. neg-sub0N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(0 - x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
      5. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
      6. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} + \left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right)\right)\right)\right)\right) \]
      7. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right) + \frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right) \]
      8. +-lowering-+.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      9. distribute-neg-frac2N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\left(\frac{1}{\mathsf{neg}\left(\left(y - 1\right)\right)}\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      10. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y - 1\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      11. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      12. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y + -1\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      13. +-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(-1 + y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      14. distribute-neg-inN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\left(\mathsf{neg}\left(-1\right)\right) + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      15. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      16. rgt-mult-inverseN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(y \cdot \frac{1}{y} + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      17. unsub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(y \cdot \frac{1}{y} - y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      18. rgt-mult-inverseN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 - y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      19. --lowering--.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
      20. /-lowering-/.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \left(x \cdot \left(y - 1\right)\right)\right)\right)\right)\right)\right) \]
      21. *-commutativeN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \left(\left(y - 1\right) \cdot x\right)\right)\right)\right)\right)\right) \]
      22. *-lowering-*.f64N/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y - 1\right), x\right)\right)\right)\right)\right)\right) \]
      23. sub-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right), x\right)\right)\right)\right)\right)\right) \]
      24. metadata-evalN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y + -1\right), x\right)\right)\right)\right)\right)\right) \]
      25. +-lowering-+.f6497.7%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\mathsf{+.f64}\left(y, -1\right), x\right)\right)\right)\right)\right)\right) \]
    7. Simplified97.7%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\left(0 - x\right) \cdot \left(\frac{1}{1 - y} + \frac{y}{\left(y + -1\right) \cdot x}\right)}\right) \]
    8. Taylor expanded in y around 0

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\color{blue}{\left(-1 \cdot x\right)}\right)\right) \]
    9. Step-by-step derivation
      1. mul-1-negN/A

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(x\right)\right)\right)\right) \]
      2. neg-lowering-neg.f6491.6%

        \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{neg.f64}\left(x\right)\right)\right) \]
    10. Simplified91.6%

      \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{-x}\right) \]
  3. Recombined 2 regimes into one program.
  4. Final simplification75.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -1.3 \cdot 10^{+18}:\\ \;\;\;\;1 + \log \left(\frac{y}{x}\right)\\ \mathbf{elif}\;y \leq 1:\\ \;\;\;\;1 - \mathsf{log1p}\left(0 - x\right)\\ \mathbf{else}:\\ \;\;\;\;1 + \log \left(\frac{y}{x}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 62.9% accurate, 1.1× speedup?

\[\begin{array}{l} \\ 1 - \mathsf{log1p}\left(0 - x\right) \end{array} \]
(FPCore (x y) :precision binary64 (- 1.0 (log1p (- 0.0 x))))
double code(double x, double y) {
	return 1.0 - log1p((0.0 - x));
}
public static double code(double x, double y) {
	return 1.0 - Math.log1p((0.0 - x));
}
def code(x, y):
	return 1.0 - math.log1p((0.0 - x))
function code(x, y)
	return Float64(1.0 - log1p(Float64(0.0 - x)))
end
code[x_, y_] := N[(1.0 - N[Log[1 + N[(0.0 - x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
1 - \mathsf{log1p}\left(0 - x\right)
\end{array}
Derivation
  1. Initial program 69.0%

    \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
  2. Step-by-step derivation
    1. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
    2. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
    3. log1p-defineN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
    4. log1p-lowering-log1p.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
    5. distribute-neg-frac2N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
    6. /-lowering-/.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
    7. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
    8. neg-sub0N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
    9. associate--r-N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
    10. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
    11. +-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
    12. +-lowering-+.f6469.1%

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
  3. Simplified69.1%

    \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around -inf

    \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\color{blue}{\left(-1 \cdot \left(x \cdot \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)}\right)\right) \]
  6. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\left(-1 \cdot x\right) \cdot \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    2. *-lowering-*.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(-1 \cdot x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    3. mul-1-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\mathsf{neg}\left(x\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    4. neg-sub0N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(0 - x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    6. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} + \left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right)\right)\right)\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right) + \frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    9. distribute-neg-frac2N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\left(\frac{1}{\mathsf{neg}\left(\left(y - 1\right)\right)}\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    10. /-lowering-/.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y - 1\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    11. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y + -1\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    13. +-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(-1 + y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    14. distribute-neg-inN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\left(\mathsf{neg}\left(-1\right)\right) + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    15. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    16. rgt-mult-inverseN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(y \cdot \frac{1}{y} + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    17. unsub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(y \cdot \frac{1}{y} - y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    18. rgt-mult-inverseN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 - y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    19. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    20. /-lowering-/.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \left(x \cdot \left(y - 1\right)\right)\right)\right)\right)\right)\right) \]
    21. *-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \left(\left(y - 1\right) \cdot x\right)\right)\right)\right)\right)\right) \]
    22. *-lowering-*.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y - 1\right), x\right)\right)\right)\right)\right)\right) \]
    23. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right), x\right)\right)\right)\right)\right)\right) \]
    24. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y + -1\right), x\right)\right)\right)\right)\right)\right) \]
    25. +-lowering-+.f6470.2%

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\mathsf{+.f64}\left(y, -1\right), x\right)\right)\right)\right)\right)\right) \]
  7. Simplified70.2%

    \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\left(0 - x\right) \cdot \left(\frac{1}{1 - y} + \frac{y}{\left(y + -1\right) \cdot x}\right)}\right) \]
  8. Taylor expanded in y around 0

    \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\color{blue}{\left(-1 \cdot x\right)}\right)\right) \]
  9. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(x\right)\right)\right)\right) \]
    2. neg-lowering-neg.f6458.6%

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{neg.f64}\left(x\right)\right)\right) \]
  10. Simplified58.6%

    \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{-x}\right) \]
  11. Final simplification58.6%

    \[\leadsto 1 - \mathsf{log1p}\left(0 - x\right) \]
  12. Add Preprocessing

Alternative 8: 42.9% accurate, 37.0× speedup?

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

\\
x + 1
\end{array}
Derivation
  1. Initial program 69.0%

    \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
  2. Step-by-step derivation
    1. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
    2. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
    3. log1p-defineN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
    4. log1p-lowering-log1p.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
    5. distribute-neg-frac2N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
    6. /-lowering-/.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
    7. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
    8. neg-sub0N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
    9. associate--r-N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
    10. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
    11. +-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
    12. +-lowering-+.f6469.1%

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
  3. Simplified69.1%

    \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around -inf

    \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\color{blue}{\left(-1 \cdot \left(x \cdot \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)}\right)\right) \]
  6. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\left(-1 \cdot x\right) \cdot \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    2. *-lowering-*.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(-1 \cdot x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    3. mul-1-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\mathsf{neg}\left(x\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    4. neg-sub0N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(0 - x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    6. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} + \left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right)\right)\right)\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right) + \frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    9. distribute-neg-frac2N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\left(\frac{1}{\mathsf{neg}\left(\left(y - 1\right)\right)}\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    10. /-lowering-/.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y - 1\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    11. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y + -1\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    13. +-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(-1 + y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    14. distribute-neg-inN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\left(\mathsf{neg}\left(-1\right)\right) + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    15. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    16. rgt-mult-inverseN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(y \cdot \frac{1}{y} + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    17. unsub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(y \cdot \frac{1}{y} - y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    18. rgt-mult-inverseN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 - y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    19. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    20. /-lowering-/.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \left(x \cdot \left(y - 1\right)\right)\right)\right)\right)\right)\right) \]
    21. *-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \left(\left(y - 1\right) \cdot x\right)\right)\right)\right)\right)\right) \]
    22. *-lowering-*.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y - 1\right), x\right)\right)\right)\right)\right)\right) \]
    23. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right), x\right)\right)\right)\right)\right)\right) \]
    24. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y + -1\right), x\right)\right)\right)\right)\right)\right) \]
    25. +-lowering-+.f6470.2%

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\mathsf{+.f64}\left(y, -1\right), x\right)\right)\right)\right)\right)\right) \]
  7. Simplified70.2%

    \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\left(0 - x\right) \cdot \left(\frac{1}{1 - y} + \frac{y}{\left(y + -1\right) \cdot x}\right)}\right) \]
  8. Taylor expanded in y around 0

    \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\color{blue}{\left(-1 \cdot x\right)}\right)\right) \]
  9. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(x\right)\right)\right)\right) \]
    2. neg-lowering-neg.f6458.6%

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{neg.f64}\left(x\right)\right)\right) \]
  10. Simplified58.6%

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

    \[\leadsto \color{blue}{1 + x} \]
  12. Step-by-step derivation
    1. +-lowering-+.f6442.3%

      \[\leadsto \mathsf{+.f64}\left(1, \color{blue}{x}\right) \]
  13. Simplified42.3%

    \[\leadsto \color{blue}{1 + x} \]
  14. Final simplification42.3%

    \[\leadsto x + 1 \]
  15. Add Preprocessing

Alternative 9: 42.6% accurate, 111.0× 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 69.0%

    \[1 - \log \left(1 - \frac{x - y}{1 - y}\right) \]
  2. Step-by-step derivation
    1. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \color{blue}{\log \left(1 - \frac{x - y}{1 - y}\right)}\right) \]
    2. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \log \left(1 + \left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
    3. log1p-defineN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \left(\mathsf{log1p}\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
    4. log1p-lowering-log1p.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(\frac{x - y}{1 - y}\right)\right)\right)\right) \]
    5. distribute-neg-frac2N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\frac{x - y}{\mathsf{neg}\left(\left(1 - y\right)\right)}\right)\right)\right) \]
    6. /-lowering-/.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\left(x - y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
    7. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\mathsf{neg}\left(\left(1 - y\right)\right)\right)\right)\right)\right) \]
    8. neg-sub0N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(0 - \left(1 - y\right)\right)\right)\right)\right) \]
    9. associate--r-N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(\left(0 - 1\right) + y\right)\right)\right)\right) \]
    10. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(-1 + y\right)\right)\right)\right) \]
    11. +-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \left(y + -1\right)\right)\right)\right) \]
    12. +-lowering-+.f6469.1%

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{/.f64}\left(\mathsf{\_.f64}\left(x, y\right), \mathsf{+.f64}\left(y, -1\right)\right)\right)\right) \]
  3. Simplified69.1%

    \[\leadsto \color{blue}{1 - \mathsf{log1p}\left(\frac{x - y}{y + -1}\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around -inf

    \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\color{blue}{\left(-1 \cdot \left(x \cdot \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)}\right)\right) \]
  6. Step-by-step derivation
    1. associate-*r*N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\left(-1 \cdot x\right) \cdot \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    2. *-lowering-*.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(-1 \cdot x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    3. mul-1-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(\mathsf{neg}\left(x\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    4. neg-sub0N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\left(0 - x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    5. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} - \frac{1}{y - 1}\right)\right)\right)\right) \]
    6. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\frac{y}{x \cdot \left(y - 1\right)} + \left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right)\right)\right)\right)\right) \]
    7. +-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \left(\left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right) + \frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right) \]
    8. +-lowering-+.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\left(\mathsf{neg}\left(\frac{1}{y - 1}\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    9. distribute-neg-frac2N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\left(\frac{1}{\mathsf{neg}\left(\left(y - 1\right)\right)}\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    10. /-lowering-/.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y - 1\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    11. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    12. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(y + -1\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    13. +-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\mathsf{neg}\left(\left(-1 + y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    14. distribute-neg-inN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(\left(\mathsf{neg}\left(-1\right)\right) + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    15. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    16. rgt-mult-inverseN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(y \cdot \frac{1}{y} + \left(\mathsf{neg}\left(y\right)\right)\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    17. unsub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(y \cdot \frac{1}{y} - y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    18. rgt-mult-inverseN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \left(1 - y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    19. --lowering--.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \left(\frac{y}{x \cdot \left(y - 1\right)}\right)\right)\right)\right)\right) \]
    20. /-lowering-/.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \left(x \cdot \left(y - 1\right)\right)\right)\right)\right)\right)\right) \]
    21. *-commutativeN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \left(\left(y - 1\right) \cdot x\right)\right)\right)\right)\right)\right) \]
    22. *-lowering-*.f64N/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y - 1\right), x\right)\right)\right)\right)\right)\right) \]
    23. sub-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y + \left(\mathsf{neg}\left(1\right)\right)\right), x\right)\right)\right)\right)\right)\right) \]
    24. metadata-evalN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\left(y + -1\right), x\right)\right)\right)\right)\right)\right) \]
    25. +-lowering-+.f6470.2%

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{*.f64}\left(\mathsf{\_.f64}\left(0, x\right), \mathsf{+.f64}\left(\mathsf{/.f64}\left(1, \mathsf{\_.f64}\left(1, y\right)\right), \mathsf{/.f64}\left(y, \mathsf{*.f64}\left(\mathsf{+.f64}\left(y, -1\right), x\right)\right)\right)\right)\right)\right) \]
  7. Simplified70.2%

    \[\leadsto 1 - \mathsf{log1p}\left(\color{blue}{\left(0 - x\right) \cdot \left(\frac{1}{1 - y} + \frac{y}{\left(y + -1\right) \cdot x}\right)}\right) \]
  8. Taylor expanded in y around 0

    \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\color{blue}{\left(-1 \cdot x\right)}\right)\right) \]
  9. Step-by-step derivation
    1. mul-1-negN/A

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\left(\mathsf{neg}\left(x\right)\right)\right)\right) \]
    2. neg-lowering-neg.f6458.6%

      \[\leadsto \mathsf{\_.f64}\left(1, \mathsf{log1p.f64}\left(\mathsf{neg.f64}\left(x\right)\right)\right) \]
  10. Simplified58.6%

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

    \[\leadsto \color{blue}{1} \]
  12. Step-by-step derivation
    1. Simplified42.0%

      \[\leadsto \color{blue}{1} \]
    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 2024152 
    (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))))))