Numeric.SpecFunctions.Extra:bd0 from math-functions-0.1.5.2

Percentage Accurate: 77.0% → 99.5%
Time: 11.1s
Alternatives: 12
Speedup: 0.5×

Specification

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

\\
x \cdot \log \left(\frac{x}{y}\right) - z
\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 12 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 77.0% accurate, 1.0× speedup?

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

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

Alternative 1: 99.5% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -5 \cdot 10^{-310}:\\ \;\;\;\;x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(\log x - \log y\right) - z\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (if (<= y -5e-310)
   (- (* x (- (log (- x)) (log (- y)))) z)
   (- (* x (- (log x) (log y))) z)))
double code(double x, double y, double z) {
	double tmp;
	if (y <= -5e-310) {
		tmp = (x * (log(-x) - log(-y))) - z;
	} else {
		tmp = (x * (log(x) - log(y))) - z;
	}
	return tmp;
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8) :: tmp
    if (y <= (-5d-310)) then
        tmp = (x * (log(-x) - log(-y))) - z
    else
        tmp = (x * (log(x) - log(y))) - z
    end if
    code = tmp
end function
public static double code(double x, double y, double z) {
	double tmp;
	if (y <= -5e-310) {
		tmp = (x * (Math.log(-x) - Math.log(-y))) - z;
	} else {
		tmp = (x * (Math.log(x) - Math.log(y))) - z;
	}
	return tmp;
}
def code(x, y, z):
	tmp = 0
	if y <= -5e-310:
		tmp = (x * (math.log(-x) - math.log(-y))) - z
	else:
		tmp = (x * (math.log(x) - math.log(y))) - z
	return tmp
function code(x, y, z)
	tmp = 0.0
	if (y <= -5e-310)
		tmp = Float64(Float64(x * Float64(log(Float64(-x)) - log(Float64(-y)))) - z);
	else
		tmp = Float64(Float64(x * Float64(log(x) - log(y))) - z);
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	tmp = 0.0;
	if (y <= -5e-310)
		tmp = (x * (log(-x) - log(-y))) - z;
	else
		tmp = (x * (log(x) - log(y))) - z;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := If[LessEqual[y, -5e-310], N[(N[(x * N[(N[Log[(-x)], $MachinePrecision] - N[Log[(-y)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -5 \cdot 10^{-310}:\\
\;\;\;\;x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right) - z\\

\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -4.999999999999985e-310

    1. Initial program 75.6%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in y around -inf 99.5%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{-1}{y}\right)\right)} - z \]
    4. Step-by-step derivation
      1. metadata-eval99.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{\color{blue}{-1}}{y}\right)\right) - z \]
      2. distribute-neg-frac99.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(-\frac{1}{y}\right)}\right) - z \]
      3. distribute-frac-neg299.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(\frac{1}{-y}\right)}\right) - z \]
      4. neg-mul-199.5%

        \[\leadsto x \cdot \left(\log \color{blue}{\left(-x\right)} + \log \left(\frac{1}{-y}\right)\right) - z \]
      5. log-rec99.5%

        \[\leadsto x \cdot \left(\log \left(-x\right) + \color{blue}{\left(-\log \left(-y\right)\right)}\right) - z \]
      6. sub-neg99.5%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    5. Simplified99.5%

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

    if -4.999999999999985e-310 < y

    1. Initial program 78.5%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 99.5%

      \[\leadsto \color{blue}{x \cdot \left(\log x + \log \left(\frac{1}{y}\right)\right)} - z \]
    4. Step-by-step derivation
      1. log-rec99.5%

        \[\leadsto x \cdot \left(\log x + \color{blue}{\left(-\log y\right)}\right) - z \]
      2. neg-mul-199.5%

        \[\leadsto x \cdot \left(\log x + \color{blue}{-1 \cdot \log y}\right) - z \]
      3. neg-mul-199.5%

        \[\leadsto x \cdot \left(\log x + \color{blue}{\left(-\log y\right)}\right) - z \]
      4. sub-neg99.5%

        \[\leadsto x \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
    5. Simplified99.5%

      \[\leadsto \color{blue}{x \cdot \left(\log x - \log y\right)} - z \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 86.1% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := x \cdot \log \left(\frac{x}{y}\right)\\ \mathbf{if}\;t\_0 \leq -\infty:\\ \;\;\;\;x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)\\ \mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+305}:\\ \;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(\log x - \log y\right)\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (let* ((t_0 (* x (log (/ x y)))))
   (if (<= t_0 (- INFINITY))
     (* x (- (log (- x)) (log (- y))))
     (if (<= t_0 5e+305)
       (- (* x (log (* x (/ 1.0 y)))) z)
       (* x (- (log x) (log y)))))))
double code(double x, double y, double z) {
	double t_0 = x * log((x / y));
	double tmp;
	if (t_0 <= -((double) INFINITY)) {
		tmp = x * (log(-x) - log(-y));
	} else if (t_0 <= 5e+305) {
		tmp = (x * log((x * (1.0 / y)))) - z;
	} else {
		tmp = x * (log(x) - log(y));
	}
	return tmp;
}
public static double code(double x, double y, double z) {
	double t_0 = x * Math.log((x / y));
	double tmp;
	if (t_0 <= -Double.POSITIVE_INFINITY) {
		tmp = x * (Math.log(-x) - Math.log(-y));
	} else if (t_0 <= 5e+305) {
		tmp = (x * Math.log((x * (1.0 / y)))) - z;
	} else {
		tmp = x * (Math.log(x) - Math.log(y));
	}
	return tmp;
}
def code(x, y, z):
	t_0 = x * math.log((x / y))
	tmp = 0
	if t_0 <= -math.inf:
		tmp = x * (math.log(-x) - math.log(-y))
	elif t_0 <= 5e+305:
		tmp = (x * math.log((x * (1.0 / y)))) - z
	else:
		tmp = x * (math.log(x) - math.log(y))
	return tmp
function code(x, y, z)
	t_0 = Float64(x * log(Float64(x / y)))
	tmp = 0.0
	if (t_0 <= Float64(-Inf))
		tmp = Float64(x * Float64(log(Float64(-x)) - log(Float64(-y))));
	elseif (t_0 <= 5e+305)
		tmp = Float64(Float64(x * log(Float64(x * Float64(1.0 / y)))) - z);
	else
		tmp = Float64(x * Float64(log(x) - log(y)));
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	t_0 = x * log((x / y));
	tmp = 0.0;
	if (t_0 <= -Inf)
		tmp = x * (log(-x) - log(-y));
	elseif (t_0 <= 5e+305)
		tmp = (x * log((x * (1.0 / y)))) - z;
	else
		tmp = x * (log(x) - log(y));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := Block[{t$95$0 = N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, (-Infinity)], N[(x * N[(N[Log[(-x)], $MachinePrecision] - N[Log[(-y)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[t$95$0, 5e+305], N[(N[(x * N[Log[N[(x * N[(1.0 / y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

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

\mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+305}:\\
\;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0

    1. Initial program 5.8%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in z around 0 5.8%

      \[\leadsto \color{blue}{x \cdot \log \left(\frac{x}{y}\right)} \]
    4. Taylor expanded in y around -inf 69.8%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{-1}{y}\right)\right)} \]
    5. Step-by-step derivation
      1. metadata-eval74.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{\color{blue}{-1}}{y}\right)\right) - z \]
      2. distribute-neg-frac74.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(-\frac{1}{y}\right)}\right) - z \]
      3. distribute-frac-neg274.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(\frac{1}{-y}\right)}\right) - z \]
      4. neg-mul-174.5%

        \[\leadsto x \cdot \left(\log \color{blue}{\left(-x\right)} + \log \left(\frac{1}{-y}\right)\right) - z \]
      5. log-rec74.5%

        \[\leadsto x \cdot \left(\log \left(-x\right) + \color{blue}{\left(-\log \left(-y\right)\right)}\right) - z \]
      6. sub-neg74.5%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    6. Simplified69.8%

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

    if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 5.00000000000000009e305

    1. Initial program 99.6%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. clear-num97.8%

        \[\leadsto x \cdot \log \color{blue}{\left(\frac{1}{\frac{y}{x}}\right)} - z \]
      2. associate-/r/99.6%

        \[\leadsto x \cdot \log \color{blue}{\left(\frac{1}{y} \cdot x\right)} - z \]
    4. Applied egg-rr99.6%

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

    if 5.00000000000000009e305 < (*.f64 x (log.f64 (/.f64 x y)))

    1. Initial program 11.7%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in z around 0 11.7%

      \[\leadsto \color{blue}{x \cdot \log \left(\frac{x}{y}\right)} \]
    4. Taylor expanded in x around 0 56.5%

      \[\leadsto \color{blue}{x \cdot \left(\log x + \log \left(\frac{1}{y}\right)\right)} \]
    5. Step-by-step derivation
      1. log-rec64.7%

        \[\leadsto x \cdot \left(\log x + \color{blue}{\left(-\log y\right)}\right) - z \]
      2. neg-mul-164.7%

        \[\leadsto x \cdot \left(\log x + \color{blue}{-1 \cdot \log y}\right) - z \]
      3. neg-mul-164.7%

        \[\leadsto x \cdot \left(\log x + \color{blue}{\left(-\log y\right)}\right) - z \]
      4. sub-neg64.7%

        \[\leadsto x \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
    6. Simplified56.5%

      \[\leadsto \color{blue}{x \cdot \left(\log x - \log y\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification90.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \cdot \log \left(\frac{x}{y}\right) \leq -\infty:\\ \;\;\;\;x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)\\ \mathbf{elif}\;x \cdot \log \left(\frac{x}{y}\right) \leq 5 \cdot 10^{+305}:\\ \;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(\log x - \log y\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 87.7% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := x \cdot \log \left(\frac{x}{y}\right)\\ \mathbf{if}\;t\_0 \leq -\infty:\\ \;\;\;\;\left(-x\right) \cdot \log \left(y \cdot x\right) - z\\ \mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+305}:\\ \;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(\log x - \log y\right)\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (let* ((t_0 (* x (log (/ x y)))))
   (if (<= t_0 (- INFINITY))
     (- (* (- x) (log (* y x))) z)
     (if (<= t_0 5e+305)
       (- (* x (log (* x (/ 1.0 y)))) z)
       (* x (- (log x) (log y)))))))
double code(double x, double y, double z) {
	double t_0 = x * log((x / y));
	double tmp;
	if (t_0 <= -((double) INFINITY)) {
		tmp = (-x * log((y * x))) - z;
	} else if (t_0 <= 5e+305) {
		tmp = (x * log((x * (1.0 / y)))) - z;
	} else {
		tmp = x * (log(x) - log(y));
	}
	return tmp;
}
public static double code(double x, double y, double z) {
	double t_0 = x * Math.log((x / y));
	double tmp;
	if (t_0 <= -Double.POSITIVE_INFINITY) {
		tmp = (-x * Math.log((y * x))) - z;
	} else if (t_0 <= 5e+305) {
		tmp = (x * Math.log((x * (1.0 / y)))) - z;
	} else {
		tmp = x * (Math.log(x) - Math.log(y));
	}
	return tmp;
}
def code(x, y, z):
	t_0 = x * math.log((x / y))
	tmp = 0
	if t_0 <= -math.inf:
		tmp = (-x * math.log((y * x))) - z
	elif t_0 <= 5e+305:
		tmp = (x * math.log((x * (1.0 / y)))) - z
	else:
		tmp = x * (math.log(x) - math.log(y))
	return tmp
function code(x, y, z)
	t_0 = Float64(x * log(Float64(x / y)))
	tmp = 0.0
	if (t_0 <= Float64(-Inf))
		tmp = Float64(Float64(Float64(-x) * log(Float64(y * x))) - z);
	elseif (t_0 <= 5e+305)
		tmp = Float64(Float64(x * log(Float64(x * Float64(1.0 / y)))) - z);
	else
		tmp = Float64(x * Float64(log(x) - log(y)));
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	t_0 = x * log((x / y));
	tmp = 0.0;
	if (t_0 <= -Inf)
		tmp = (-x * log((y * x))) - z;
	elseif (t_0 <= 5e+305)
		tmp = (x * log((x * (1.0 / y)))) - z;
	else
		tmp = x * (log(x) - log(y));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := Block[{t$95$0 = N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, (-Infinity)], N[(N[((-x) * N[Log[N[(y * x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], If[LessEqual[t$95$0, 5e+305], N[(N[(x * N[Log[N[(x * N[(1.0 / y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
\begin{array}{l}

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

\mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+305}:\\
\;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0

    1. Initial program 5.8%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in y around -inf 74.5%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{-1}{y}\right)\right)} - z \]
    4. Step-by-step derivation
      1. metadata-eval74.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{\color{blue}{-1}}{y}\right)\right) - z \]
      2. distribute-neg-frac74.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(-\frac{1}{y}\right)}\right) - z \]
      3. distribute-frac-neg274.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(\frac{1}{-y}\right)}\right) - z \]
      4. neg-mul-174.5%

        \[\leadsto x \cdot \left(\log \color{blue}{\left(-x\right)} + \log \left(\frac{1}{-y}\right)\right) - z \]
      5. log-rec74.5%

        \[\leadsto x \cdot \left(\log \left(-x\right) + \color{blue}{\left(-\log \left(-y\right)\right)}\right) - z \]
      6. sub-neg74.5%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    5. Simplified74.5%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    6. Step-by-step derivation
      1. sub-neg74.5%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) + \left(-\log \left(-y\right)\right)\right)} - z \]
      2. distribute-rgt-in74.7%

        \[\leadsto \color{blue}{\left(\log \left(-x\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right)} - z \]
      3. add-sqr-sqrt74.7%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{-x} \cdot \sqrt{-x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      4. sqrt-unprod25.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{\left(-x\right) \cdot \left(-x\right)}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      5. sqr-neg25.0%

        \[\leadsto \left(\log \left(\sqrt{\color{blue}{x \cdot x}}\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      6. sqrt-unprod0.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      7. add-sqr-sqrt0.0%

        \[\leadsto \left(\log \color{blue}{x} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      8. add-sqr-sqrt0.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{-y} \cdot \sqrt{-y}\right)}\right) \cdot x\right) - z \]
      9. sqrt-unprod0.6%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{\left(-y\right) \cdot \left(-y\right)}\right)}\right) \cdot x\right) - z \]
      10. sqr-neg0.6%

        \[\leadsto \left(\log x \cdot x + \left(-\log \left(\sqrt{\color{blue}{y \cdot y}}\right)\right) \cdot x\right) - z \]
      11. sqrt-unprod25.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{y} \cdot \sqrt{y}\right)}\right) \cdot x\right) - z \]
      12. add-sqr-sqrt25.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{y}\right) \cdot x\right) - z \]
    7. Applied egg-rr25.0%

      \[\leadsto \color{blue}{\left(\log x \cdot x + \left(-\log y\right) \cdot x\right)} - z \]
    8. Step-by-step derivation
      1. +-commutative25.0%

        \[\leadsto \color{blue}{\left(\left(-\log y\right) \cdot x + \log x \cdot x\right)} - z \]
      2. distribute-rgt-out25.0%

        \[\leadsto \color{blue}{x \cdot \left(\left(-\log y\right) + \log x\right)} - z \]
      3. neg-sub025.0%

        \[\leadsto x \cdot \left(\color{blue}{\left(0 - \log y\right)} + \log x\right) - z \]
      4. associate--r-25.0%

        \[\leadsto x \cdot \color{blue}{\left(0 - \left(\log y - \log x\right)\right)} - z \]
      5. log-div15.2%

        \[\leadsto x \cdot \left(0 - \color{blue}{\log \left(\frac{y}{x}\right)}\right) - z \]
      6. neg-sub015.2%

        \[\leadsto x \cdot \color{blue}{\left(-\log \left(\frac{y}{x}\right)\right)} - z \]
      7. distribute-rgt-neg-out15.2%

        \[\leadsto \color{blue}{\left(-x \cdot \log \left(\frac{y}{x}\right)\right)} - z \]
      8. distribute-lft-neg-in15.2%

        \[\leadsto \color{blue}{\left(-x\right) \cdot \log \left(\frac{y}{x}\right)} - z \]
      9. add-sqr-sqrt0.6%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\sqrt{\log \left(\frac{y}{x}\right)} \cdot \sqrt{\log \left(\frac{y}{x}\right)}\right)} - z \]
      10. sqrt-unprod0.7%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\sqrt{\log \left(\frac{y}{x}\right) \cdot \log \left(\frac{y}{x}\right)}} - z \]
      11. sqr-neg0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\color{blue}{\left(-\log \left(\frac{y}{x}\right)\right) \cdot \left(-\log \left(\frac{y}{x}\right)\right)}} - z \]
      12. neg-log0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\color{blue}{\log \left(\frac{1}{\frac{y}{x}}\right)} \cdot \left(-\log \left(\frac{y}{x}\right)\right)} - z \]
      13. clear-num0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\log \color{blue}{\left(\frac{x}{y}\right)} \cdot \left(-\log \left(\frac{y}{x}\right)\right)} - z \]
      14. neg-log0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\log \left(\frac{x}{y}\right) \cdot \color{blue}{\log \left(\frac{1}{\frac{y}{x}}\right)}} - z \]
      15. clear-num0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\log \left(\frac{x}{y}\right) \cdot \log \color{blue}{\left(\frac{x}{y}\right)}} - z \]
      16. sqrt-unprod0.1%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\sqrt{\log \left(\frac{x}{y}\right)} \cdot \sqrt{\log \left(\frac{x}{y}\right)}\right)} - z \]
      17. add-sqr-sqrt0.6%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\log \left(\frac{x}{y}\right)} - z \]
      18. log-div20.9%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
      19. sub-neg20.9%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\log x + \left(-\log y\right)\right)} - z \]
      20. add-log-exp20.9%

        \[\leadsto \left(-x\right) \cdot \left(\log x + \color{blue}{\log \left(e^{-\log y}\right)}\right) - z \]
      21. sum-log0.5%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\log \left(x \cdot e^{-\log y}\right)} - z \]
    9. Applied egg-rr32.5%

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

    if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 5.00000000000000009e305

    1. Initial program 99.6%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. clear-num97.8%

        \[\leadsto x \cdot \log \color{blue}{\left(\frac{1}{\frac{y}{x}}\right)} - z \]
      2. associate-/r/99.6%

        \[\leadsto x \cdot \log \color{blue}{\left(\frac{1}{y} \cdot x\right)} - z \]
    4. Applied egg-rr99.6%

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

    if 5.00000000000000009e305 < (*.f64 x (log.f64 (/.f64 x y)))

    1. Initial program 11.7%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in z around 0 11.7%

      \[\leadsto \color{blue}{x \cdot \log \left(\frac{x}{y}\right)} \]
    4. Taylor expanded in x around 0 56.5%

      \[\leadsto \color{blue}{x \cdot \left(\log x + \log \left(\frac{1}{y}\right)\right)} \]
    5. Step-by-step derivation
      1. log-rec64.7%

        \[\leadsto x \cdot \left(\log x + \color{blue}{\left(-\log y\right)}\right) - z \]
      2. neg-mul-164.7%

        \[\leadsto x \cdot \left(\log x + \color{blue}{-1 \cdot \log y}\right) - z \]
      3. neg-mul-164.7%

        \[\leadsto x \cdot \left(\log x + \color{blue}{\left(-\log y\right)}\right) - z \]
      4. sub-neg64.7%

        \[\leadsto x \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
    6. Simplified56.5%

      \[\leadsto \color{blue}{x \cdot \left(\log x - \log y\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification86.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \cdot \log \left(\frac{x}{y}\right) \leq -\infty:\\ \;\;\;\;\left(-x\right) \cdot \log \left(y \cdot x\right) - z\\ \mathbf{elif}\;x \cdot \log \left(\frac{x}{y}\right) \leq 5 \cdot 10^{+305}:\\ \;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(\log x - \log y\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 88.2% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := x \cdot \log \left(\frac{x}{y}\right)\\ t_1 := \log \left(y \cdot x\right)\\ \mathbf{if}\;t\_0 \leq -\infty:\\ \;\;\;\;\left(-x\right) \cdot t\_1 - z\\ \mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+305}:\\ \;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot t\_1 - z\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (let* ((t_0 (* x (log (/ x y)))) (t_1 (log (* y x))))
   (if (<= t_0 (- INFINITY))
     (- (* (- x) t_1) z)
     (if (<= t_0 5e+305) (- (* x (log (* x (/ 1.0 y)))) z) (- (* x t_1) z)))))
double code(double x, double y, double z) {
	double t_0 = x * log((x / y));
	double t_1 = log((y * x));
	double tmp;
	if (t_0 <= -((double) INFINITY)) {
		tmp = (-x * t_1) - z;
	} else if (t_0 <= 5e+305) {
		tmp = (x * log((x * (1.0 / y)))) - z;
	} else {
		tmp = (x * t_1) - z;
	}
	return tmp;
}
public static double code(double x, double y, double z) {
	double t_0 = x * Math.log((x / y));
	double t_1 = Math.log((y * x));
	double tmp;
	if (t_0 <= -Double.POSITIVE_INFINITY) {
		tmp = (-x * t_1) - z;
	} else if (t_0 <= 5e+305) {
		tmp = (x * Math.log((x * (1.0 / y)))) - z;
	} else {
		tmp = (x * t_1) - z;
	}
	return tmp;
}
def code(x, y, z):
	t_0 = x * math.log((x / y))
	t_1 = math.log((y * x))
	tmp = 0
	if t_0 <= -math.inf:
		tmp = (-x * t_1) - z
	elif t_0 <= 5e+305:
		tmp = (x * math.log((x * (1.0 / y)))) - z
	else:
		tmp = (x * t_1) - z
	return tmp
function code(x, y, z)
	t_0 = Float64(x * log(Float64(x / y)))
	t_1 = log(Float64(y * x))
	tmp = 0.0
	if (t_0 <= Float64(-Inf))
		tmp = Float64(Float64(Float64(-x) * t_1) - z);
	elseif (t_0 <= 5e+305)
		tmp = Float64(Float64(x * log(Float64(x * Float64(1.0 / y)))) - z);
	else
		tmp = Float64(Float64(x * t_1) - z);
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	t_0 = x * log((x / y));
	t_1 = log((y * x));
	tmp = 0.0;
	if (t_0 <= -Inf)
		tmp = (-x * t_1) - z;
	elseif (t_0 <= 5e+305)
		tmp = (x * log((x * (1.0 / y)))) - z;
	else
		tmp = (x * t_1) - z;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := Block[{t$95$0 = N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Log[N[(y * x), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$0, (-Infinity)], N[(N[((-x) * t$95$1), $MachinePrecision] - z), $MachinePrecision], If[LessEqual[t$95$0, 5e+305], N[(N[(x * N[Log[N[(x * N[(1.0 / y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(N[(x * t$95$1), $MachinePrecision] - z), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := x \cdot \log \left(\frac{x}{y}\right)\\
t_1 := \log \left(y \cdot x\right)\\
\mathbf{if}\;t\_0 \leq -\infty:\\
\;\;\;\;\left(-x\right) \cdot t\_1 - z\\

\mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+305}:\\
\;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\

\mathbf{else}:\\
\;\;\;\;x \cdot t\_1 - z\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0

    1. Initial program 5.8%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in y around -inf 74.5%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{-1}{y}\right)\right)} - z \]
    4. Step-by-step derivation
      1. metadata-eval74.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{\color{blue}{-1}}{y}\right)\right) - z \]
      2. distribute-neg-frac74.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(-\frac{1}{y}\right)}\right) - z \]
      3. distribute-frac-neg274.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(\frac{1}{-y}\right)}\right) - z \]
      4. neg-mul-174.5%

        \[\leadsto x \cdot \left(\log \color{blue}{\left(-x\right)} + \log \left(\frac{1}{-y}\right)\right) - z \]
      5. log-rec74.5%

        \[\leadsto x \cdot \left(\log \left(-x\right) + \color{blue}{\left(-\log \left(-y\right)\right)}\right) - z \]
      6. sub-neg74.5%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    5. Simplified74.5%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    6. Step-by-step derivation
      1. sub-neg74.5%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) + \left(-\log \left(-y\right)\right)\right)} - z \]
      2. distribute-rgt-in74.7%

        \[\leadsto \color{blue}{\left(\log \left(-x\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right)} - z \]
      3. add-sqr-sqrt74.7%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{-x} \cdot \sqrt{-x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      4. sqrt-unprod25.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{\left(-x\right) \cdot \left(-x\right)}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      5. sqr-neg25.0%

        \[\leadsto \left(\log \left(\sqrt{\color{blue}{x \cdot x}}\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      6. sqrt-unprod0.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      7. add-sqr-sqrt0.0%

        \[\leadsto \left(\log \color{blue}{x} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      8. add-sqr-sqrt0.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{-y} \cdot \sqrt{-y}\right)}\right) \cdot x\right) - z \]
      9. sqrt-unprod0.6%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{\left(-y\right) \cdot \left(-y\right)}\right)}\right) \cdot x\right) - z \]
      10. sqr-neg0.6%

        \[\leadsto \left(\log x \cdot x + \left(-\log \left(\sqrt{\color{blue}{y \cdot y}}\right)\right) \cdot x\right) - z \]
      11. sqrt-unprod25.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{y} \cdot \sqrt{y}\right)}\right) \cdot x\right) - z \]
      12. add-sqr-sqrt25.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{y}\right) \cdot x\right) - z \]
    7. Applied egg-rr25.0%

      \[\leadsto \color{blue}{\left(\log x \cdot x + \left(-\log y\right) \cdot x\right)} - z \]
    8. Step-by-step derivation
      1. +-commutative25.0%

        \[\leadsto \color{blue}{\left(\left(-\log y\right) \cdot x + \log x \cdot x\right)} - z \]
      2. distribute-rgt-out25.0%

        \[\leadsto \color{blue}{x \cdot \left(\left(-\log y\right) + \log x\right)} - z \]
      3. neg-sub025.0%

        \[\leadsto x \cdot \left(\color{blue}{\left(0 - \log y\right)} + \log x\right) - z \]
      4. associate--r-25.0%

        \[\leadsto x \cdot \color{blue}{\left(0 - \left(\log y - \log x\right)\right)} - z \]
      5. log-div15.2%

        \[\leadsto x \cdot \left(0 - \color{blue}{\log \left(\frac{y}{x}\right)}\right) - z \]
      6. neg-sub015.2%

        \[\leadsto x \cdot \color{blue}{\left(-\log \left(\frac{y}{x}\right)\right)} - z \]
      7. distribute-rgt-neg-out15.2%

        \[\leadsto \color{blue}{\left(-x \cdot \log \left(\frac{y}{x}\right)\right)} - z \]
      8. distribute-lft-neg-in15.2%

        \[\leadsto \color{blue}{\left(-x\right) \cdot \log \left(\frac{y}{x}\right)} - z \]
      9. add-sqr-sqrt0.6%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\sqrt{\log \left(\frac{y}{x}\right)} \cdot \sqrt{\log \left(\frac{y}{x}\right)}\right)} - z \]
      10. sqrt-unprod0.7%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\sqrt{\log \left(\frac{y}{x}\right) \cdot \log \left(\frac{y}{x}\right)}} - z \]
      11. sqr-neg0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\color{blue}{\left(-\log \left(\frac{y}{x}\right)\right) \cdot \left(-\log \left(\frac{y}{x}\right)\right)}} - z \]
      12. neg-log0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\color{blue}{\log \left(\frac{1}{\frac{y}{x}}\right)} \cdot \left(-\log \left(\frac{y}{x}\right)\right)} - z \]
      13. clear-num0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\log \color{blue}{\left(\frac{x}{y}\right)} \cdot \left(-\log \left(\frac{y}{x}\right)\right)} - z \]
      14. neg-log0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\log \left(\frac{x}{y}\right) \cdot \color{blue}{\log \left(\frac{1}{\frac{y}{x}}\right)}} - z \]
      15. clear-num0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\log \left(\frac{x}{y}\right) \cdot \log \color{blue}{\left(\frac{x}{y}\right)}} - z \]
      16. sqrt-unprod0.1%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\sqrt{\log \left(\frac{x}{y}\right)} \cdot \sqrt{\log \left(\frac{x}{y}\right)}\right)} - z \]
      17. add-sqr-sqrt0.6%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\log \left(\frac{x}{y}\right)} - z \]
      18. log-div20.9%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
      19. sub-neg20.9%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\log x + \left(-\log y\right)\right)} - z \]
      20. add-log-exp20.9%

        \[\leadsto \left(-x\right) \cdot \left(\log x + \color{blue}{\log \left(e^{-\log y}\right)}\right) - z \]
      21. sum-log0.5%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\log \left(x \cdot e^{-\log y}\right)} - z \]
    9. Applied egg-rr32.5%

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

    if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 5.00000000000000009e305

    1. Initial program 99.6%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. clear-num97.8%

        \[\leadsto x \cdot \log \color{blue}{\left(\frac{1}{\frac{y}{x}}\right)} - z \]
      2. associate-/r/99.6%

        \[\leadsto x \cdot \log \color{blue}{\left(\frac{1}{y} \cdot x\right)} - z \]
    4. Applied egg-rr99.6%

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

    if 5.00000000000000009e305 < (*.f64 x (log.f64 (/.f64 x y)))

    1. Initial program 11.7%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in y around -inf 35.0%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{-1}{y}\right)\right)} - z \]
    4. Step-by-step derivation
      1. metadata-eval35.0%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{\color{blue}{-1}}{y}\right)\right) - z \]
      2. distribute-neg-frac35.0%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(-\frac{1}{y}\right)}\right) - z \]
      3. distribute-frac-neg235.0%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(\frac{1}{-y}\right)}\right) - z \]
      4. neg-mul-135.0%

        \[\leadsto x \cdot \left(\log \color{blue}{\left(-x\right)} + \log \left(\frac{1}{-y}\right)\right) - z \]
      5. log-rec35.0%

        \[\leadsto x \cdot \left(\log \left(-x\right) + \color{blue}{\left(-\log \left(-y\right)\right)}\right) - z \]
      6. sub-neg35.0%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    5. Simplified35.0%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    6. Step-by-step derivation
      1. sub-neg35.0%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) + \left(-\log \left(-y\right)\right)\right)} - z \]
      2. distribute-rgt-in35.0%

        \[\leadsto \color{blue}{\left(\log \left(-x\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right)} - z \]
      3. add-sqr-sqrt35.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{-x} \cdot \sqrt{-x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      4. sqrt-unprod8.1%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{\left(-x\right) \cdot \left(-x\right)}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      5. sqr-neg8.1%

        \[\leadsto \left(\log \left(\sqrt{\color{blue}{x \cdot x}}\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      6. sqrt-unprod0.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      7. add-sqr-sqrt0.0%

        \[\leadsto \left(\log \color{blue}{x} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      8. add-sqr-sqrt0.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{-y} \cdot \sqrt{-y}\right)}\right) \cdot x\right) - z \]
      9. sqrt-unprod24.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{\left(-y\right) \cdot \left(-y\right)}\right)}\right) \cdot x\right) - z \]
      10. sqr-neg24.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \left(\sqrt{\color{blue}{y \cdot y}}\right)\right) \cdot x\right) - z \]
      11. sqrt-unprod62.4%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{y} \cdot \sqrt{y}\right)}\right) \cdot x\right) - z \]
      12. add-sqr-sqrt62.4%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{y}\right) \cdot x\right) - z \]
    7. Applied egg-rr62.4%

      \[\leadsto \color{blue}{\left(\log x \cdot x + \left(-\log y\right) \cdot x\right)} - z \]
    8. Step-by-step derivation
      1. distribute-rgt-out64.7%

        \[\leadsto \color{blue}{x \cdot \left(\log x + \left(-\log y\right)\right)} - z \]
      2. sub-neg64.7%

        \[\leadsto x \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
      3. log-div11.7%

        \[\leadsto x \cdot \color{blue}{\log \left(\frac{x}{y}\right)} - z \]
      4. *-commutative11.7%

        \[\leadsto \color{blue}{\log \left(\frac{x}{y}\right) \cdot x} - z \]
      5. log-div64.7%

        \[\leadsto \color{blue}{\left(\log x - \log y\right)} \cdot x - z \]
      6. sub-neg64.7%

        \[\leadsto \color{blue}{\left(\log x + \left(-\log y\right)\right)} \cdot x - z \]
      7. add-log-exp64.7%

        \[\leadsto \left(\log x + \color{blue}{\log \left(e^{-\log y}\right)}\right) \cdot x - z \]
      8. sum-log11.1%

        \[\leadsto \color{blue}{\log \left(x \cdot e^{-\log y}\right)} \cdot x - z \]
      9. add-sqr-sqrt6.1%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\sqrt{-\log y} \cdot \sqrt{-\log y}}}\right) \cdot x - z \]
      10. sqrt-unprod11.1%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\sqrt{\left(-\log y\right) \cdot \left(-\log y\right)}}}\right) \cdot x - z \]
      11. sqr-neg11.1%

        \[\leadsto \log \left(x \cdot e^{\sqrt{\color{blue}{\log y \cdot \log y}}}\right) \cdot x - z \]
      12. sqrt-unprod5.0%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\sqrt{\log y} \cdot \sqrt{\log y}}}\right) \cdot x - z \]
      13. add-sqr-sqrt16.7%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\log y}}\right) \cdot x - z \]
      14. add-exp-log49.3%

        \[\leadsto \log \left(x \cdot \color{blue}{y}\right) \cdot x - z \]
    9. Applied egg-rr49.3%

      \[\leadsto \color{blue}{\log \left(x \cdot y\right) \cdot x} - z \]
  3. Recombined 3 regimes into one program.
  4. Final simplification85.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \cdot \log \left(\frac{x}{y}\right) \leq -\infty:\\ \;\;\;\;\left(-x\right) \cdot \log \left(y \cdot x\right) - z\\ \mathbf{elif}\;x \cdot \log \left(\frac{x}{y}\right) \leq 5 \cdot 10^{+305}:\\ \;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \log \left(y \cdot x\right) - z\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 88.5% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := x \cdot \log \left(\frac{x}{y}\right)\\ \mathbf{if}\;t\_0 \leq -\infty \lor \neg \left(t\_0 \leq 5 \cdot 10^{+305}\right):\\ \;\;\;\;x \cdot \log \left(y \cdot x\right) - z\\ \mathbf{else}:\\ \;\;\;\;t\_0 - z\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (let* ((t_0 (* x (log (/ x y)))))
   (if (or (<= t_0 (- INFINITY)) (not (<= t_0 5e+305)))
     (- (* x (log (* y x))) z)
     (- t_0 z))))
double code(double x, double y, double z) {
	double t_0 = x * log((x / y));
	double tmp;
	if ((t_0 <= -((double) INFINITY)) || !(t_0 <= 5e+305)) {
		tmp = (x * log((y * x))) - z;
	} else {
		tmp = t_0 - z;
	}
	return tmp;
}
public static double code(double x, double y, double z) {
	double t_0 = x * Math.log((x / y));
	double tmp;
	if ((t_0 <= -Double.POSITIVE_INFINITY) || !(t_0 <= 5e+305)) {
		tmp = (x * Math.log((y * x))) - z;
	} else {
		tmp = t_0 - z;
	}
	return tmp;
}
def code(x, y, z):
	t_0 = x * math.log((x / y))
	tmp = 0
	if (t_0 <= -math.inf) or not (t_0 <= 5e+305):
		tmp = (x * math.log((y * x))) - z
	else:
		tmp = t_0 - z
	return tmp
function code(x, y, z)
	t_0 = Float64(x * log(Float64(x / y)))
	tmp = 0.0
	if ((t_0 <= Float64(-Inf)) || !(t_0 <= 5e+305))
		tmp = Float64(Float64(x * log(Float64(y * x))) - z);
	else
		tmp = Float64(t_0 - z);
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	t_0 = x * log((x / y));
	tmp = 0.0;
	if ((t_0 <= -Inf) || ~((t_0 <= 5e+305)))
		tmp = (x * log((y * x))) - z;
	else
		tmp = t_0 - z;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := Block[{t$95$0 = N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$0, (-Infinity)], N[Not[LessEqual[t$95$0, 5e+305]], $MachinePrecision]], N[(N[(x * N[Log[N[(y * x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(t$95$0 - z), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := x \cdot \log \left(\frac{x}{y}\right)\\
\mathbf{if}\;t\_0 \leq -\infty \lor \neg \left(t\_0 \leq 5 \cdot 10^{+305}\right):\\
\;\;\;\;x \cdot \log \left(y \cdot x\right) - z\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0 or 5.00000000000000009e305 < (*.f64 x (log.f64 (/.f64 x y)))

    1. Initial program 9.5%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in y around -inf 49.8%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{-1}{y}\right)\right)} - z \]
    4. Step-by-step derivation
      1. metadata-eval49.8%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{\color{blue}{-1}}{y}\right)\right) - z \]
      2. distribute-neg-frac49.8%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(-\frac{1}{y}\right)}\right) - z \]
      3. distribute-frac-neg249.8%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(\frac{1}{-y}\right)}\right) - z \]
      4. neg-mul-149.8%

        \[\leadsto x \cdot \left(\log \color{blue}{\left(-x\right)} + \log \left(\frac{1}{-y}\right)\right) - z \]
      5. log-rec49.8%

        \[\leadsto x \cdot \left(\log \left(-x\right) + \color{blue}{\left(-\log \left(-y\right)\right)}\right) - z \]
      6. sub-neg49.8%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    5. Simplified49.8%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    6. Step-by-step derivation
      1. sub-neg49.8%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) + \left(-\log \left(-y\right)\right)\right)} - z \]
      2. distribute-rgt-in49.9%

        \[\leadsto \color{blue}{\left(\log \left(-x\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right)} - z \]
      3. add-sqr-sqrt49.9%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{-x} \cdot \sqrt{-x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      4. sqrt-unprod14.4%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{\left(-x\right) \cdot \left(-x\right)}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      5. sqr-neg14.4%

        \[\leadsto \left(\log \left(\sqrt{\color{blue}{x \cdot x}}\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      6. sqrt-unprod0.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      7. add-sqr-sqrt0.0%

        \[\leadsto \left(\log \color{blue}{x} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      8. add-sqr-sqrt0.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{-y} \cdot \sqrt{-y}\right)}\right) \cdot x\right) - z \]
      9. sqrt-unprod15.2%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{\left(-y\right) \cdot \left(-y\right)}\right)}\right) \cdot x\right) - z \]
      10. sqr-neg15.2%

        \[\leadsto \left(\log x \cdot x + \left(-\log \left(\sqrt{\color{blue}{y \cdot y}}\right)\right) \cdot x\right) - z \]
      11. sqrt-unprod48.4%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{y} \cdot \sqrt{y}\right)}\right) \cdot x\right) - z \]
      12. add-sqr-sqrt48.4%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{y}\right) \cdot x\right) - z \]
    7. Applied egg-rr48.4%

      \[\leadsto \color{blue}{\left(\log x \cdot x + \left(-\log y\right) \cdot x\right)} - z \]
    8. Step-by-step derivation
      1. distribute-rgt-out49.8%

        \[\leadsto \color{blue}{x \cdot \left(\log x + \left(-\log y\right)\right)} - z \]
      2. sub-neg49.8%

        \[\leadsto x \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
      3. log-div9.5%

        \[\leadsto x \cdot \color{blue}{\log \left(\frac{x}{y}\right)} - z \]
      4. *-commutative9.5%

        \[\leadsto \color{blue}{\log \left(\frac{x}{y}\right) \cdot x} - z \]
      5. log-div49.8%

        \[\leadsto \color{blue}{\left(\log x - \log y\right)} \cdot x - z \]
      6. sub-neg49.8%

        \[\leadsto \color{blue}{\left(\log x + \left(-\log y\right)\right)} \cdot x - z \]
      7. add-log-exp49.8%

        \[\leadsto \left(\log x + \color{blue}{\log \left(e^{-\log y}\right)}\right) \cdot x - z \]
      8. sum-log7.1%

        \[\leadsto \color{blue}{\log \left(x \cdot e^{-\log y}\right)} \cdot x - z \]
      9. add-sqr-sqrt3.8%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\sqrt{-\log y} \cdot \sqrt{-\log y}}}\right) \cdot x - z \]
      10. sqrt-unprod14.8%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\sqrt{\left(-\log y\right) \cdot \left(-\log y\right)}}}\right) \cdot x - z \]
      11. sqr-neg14.8%

        \[\leadsto \log \left(x \cdot e^{\sqrt{\color{blue}{\log y \cdot \log y}}}\right) \cdot x - z \]
      12. sqrt-unprod11.0%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\sqrt{\log y} \cdot \sqrt{\log y}}}\right) \cdot x - z \]
      13. add-sqr-sqrt18.3%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\log y}}\right) \cdot x - z \]
      14. add-exp-log42.4%

        \[\leadsto \log \left(x \cdot \color{blue}{y}\right) \cdot x - z \]
    9. Applied egg-rr42.4%

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

    if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 5.00000000000000009e305

    1. Initial program 99.6%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification85.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \cdot \log \left(\frac{x}{y}\right) \leq -\infty \lor \neg \left(x \cdot \log \left(\frac{x}{y}\right) \leq 5 \cdot 10^{+305}\right):\\ \;\;\;\;x \cdot \log \left(y \cdot x\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \log \left(\frac{x}{y}\right) - z\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 87.5% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := x \cdot \log \left(\frac{x}{y}\right)\\ \mathbf{if}\;t\_0 \leq -\infty \lor \neg \left(t\_0 \leq 5 \cdot 10^{+305}\right):\\ \;\;\;\;-z\\ \mathbf{else}:\\ \;\;\;\;t\_0 - z\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (let* ((t_0 (* x (log (/ x y)))))
   (if (or (<= t_0 (- INFINITY)) (not (<= t_0 5e+305))) (- z) (- t_0 z))))
double code(double x, double y, double z) {
	double t_0 = x * log((x / y));
	double tmp;
	if ((t_0 <= -((double) INFINITY)) || !(t_0 <= 5e+305)) {
		tmp = -z;
	} else {
		tmp = t_0 - z;
	}
	return tmp;
}
public static double code(double x, double y, double z) {
	double t_0 = x * Math.log((x / y));
	double tmp;
	if ((t_0 <= -Double.POSITIVE_INFINITY) || !(t_0 <= 5e+305)) {
		tmp = -z;
	} else {
		tmp = t_0 - z;
	}
	return tmp;
}
def code(x, y, z):
	t_0 = x * math.log((x / y))
	tmp = 0
	if (t_0 <= -math.inf) or not (t_0 <= 5e+305):
		tmp = -z
	else:
		tmp = t_0 - z
	return tmp
function code(x, y, z)
	t_0 = Float64(x * log(Float64(x / y)))
	tmp = 0.0
	if ((t_0 <= Float64(-Inf)) || !(t_0 <= 5e+305))
		tmp = Float64(-z);
	else
		tmp = Float64(t_0 - z);
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	t_0 = x * log((x / y));
	tmp = 0.0;
	if ((t_0 <= -Inf) || ~((t_0 <= 5e+305)))
		tmp = -z;
	else
		tmp = t_0 - z;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := Block[{t$95$0 = N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, If[Or[LessEqual[t$95$0, (-Infinity)], N[Not[LessEqual[t$95$0, 5e+305]], $MachinePrecision]], (-z), N[(t$95$0 - z), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := x \cdot \log \left(\frac{x}{y}\right)\\
\mathbf{if}\;t\_0 \leq -\infty \lor \neg \left(t\_0 \leq 5 \cdot 10^{+305}\right):\\
\;\;\;\;-z\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0 or 5.00000000000000009e305 < (*.f64 x (log.f64 (/.f64 x y)))

    1. Initial program 9.5%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 36.0%

      \[\leadsto \color{blue}{-1 \cdot z} \]
    4. Step-by-step derivation
      1. neg-mul-136.0%

        \[\leadsto \color{blue}{-z} \]
    5. Simplified36.0%

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

    if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 5.00000000000000009e305

    1. Initial program 99.6%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification83.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \cdot \log \left(\frac{x}{y}\right) \leq -\infty \lor \neg \left(x \cdot \log \left(\frac{x}{y}\right) \leq 5 \cdot 10^{+305}\right):\\ \;\;\;\;-z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \log \left(\frac{x}{y}\right) - z\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 88.2% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := x \cdot \log \left(\frac{x}{y}\right)\\ t_1 := \log \left(y \cdot x\right)\\ \mathbf{if}\;t\_0 \leq -\infty:\\ \;\;\;\;\left(-x\right) \cdot t\_1 - z\\ \mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+305}:\\ \;\;\;\;t\_0 - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot t\_1 - z\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (let* ((t_0 (* x (log (/ x y)))) (t_1 (log (* y x))))
   (if (<= t_0 (- INFINITY))
     (- (* (- x) t_1) z)
     (if (<= t_0 5e+305) (- t_0 z) (- (* x t_1) z)))))
double code(double x, double y, double z) {
	double t_0 = x * log((x / y));
	double t_1 = log((y * x));
	double tmp;
	if (t_0 <= -((double) INFINITY)) {
		tmp = (-x * t_1) - z;
	} else if (t_0 <= 5e+305) {
		tmp = t_0 - z;
	} else {
		tmp = (x * t_1) - z;
	}
	return tmp;
}
public static double code(double x, double y, double z) {
	double t_0 = x * Math.log((x / y));
	double t_1 = Math.log((y * x));
	double tmp;
	if (t_0 <= -Double.POSITIVE_INFINITY) {
		tmp = (-x * t_1) - z;
	} else if (t_0 <= 5e+305) {
		tmp = t_0 - z;
	} else {
		tmp = (x * t_1) - z;
	}
	return tmp;
}
def code(x, y, z):
	t_0 = x * math.log((x / y))
	t_1 = math.log((y * x))
	tmp = 0
	if t_0 <= -math.inf:
		tmp = (-x * t_1) - z
	elif t_0 <= 5e+305:
		tmp = t_0 - z
	else:
		tmp = (x * t_1) - z
	return tmp
function code(x, y, z)
	t_0 = Float64(x * log(Float64(x / y)))
	t_1 = log(Float64(y * x))
	tmp = 0.0
	if (t_0 <= Float64(-Inf))
		tmp = Float64(Float64(Float64(-x) * t_1) - z);
	elseif (t_0 <= 5e+305)
		tmp = Float64(t_0 - z);
	else
		tmp = Float64(Float64(x * t_1) - z);
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	t_0 = x * log((x / y));
	t_1 = log((y * x));
	tmp = 0.0;
	if (t_0 <= -Inf)
		tmp = (-x * t_1) - z;
	elseif (t_0 <= 5e+305)
		tmp = t_0 - z;
	else
		tmp = (x * t_1) - z;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := Block[{t$95$0 = N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Log[N[(y * x), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[t$95$0, (-Infinity)], N[(N[((-x) * t$95$1), $MachinePrecision] - z), $MachinePrecision], If[LessEqual[t$95$0, 5e+305], N[(t$95$0 - z), $MachinePrecision], N[(N[(x * t$95$1), $MachinePrecision] - z), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := x \cdot \log \left(\frac{x}{y}\right)\\
t_1 := \log \left(y \cdot x\right)\\
\mathbf{if}\;t\_0 \leq -\infty:\\
\;\;\;\;\left(-x\right) \cdot t\_1 - z\\

\mathbf{elif}\;t\_0 \leq 5 \cdot 10^{+305}:\\
\;\;\;\;t\_0 - z\\

\mathbf{else}:\\
\;\;\;\;x \cdot t\_1 - z\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if (*.f64 x (log.f64 (/.f64 x y))) < -inf.0

    1. Initial program 5.8%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in y around -inf 74.5%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{-1}{y}\right)\right)} - z \]
    4. Step-by-step derivation
      1. metadata-eval74.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{\color{blue}{-1}}{y}\right)\right) - z \]
      2. distribute-neg-frac74.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(-\frac{1}{y}\right)}\right) - z \]
      3. distribute-frac-neg274.5%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(\frac{1}{-y}\right)}\right) - z \]
      4. neg-mul-174.5%

        \[\leadsto x \cdot \left(\log \color{blue}{\left(-x\right)} + \log \left(\frac{1}{-y}\right)\right) - z \]
      5. log-rec74.5%

        \[\leadsto x \cdot \left(\log \left(-x\right) + \color{blue}{\left(-\log \left(-y\right)\right)}\right) - z \]
      6. sub-neg74.5%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    5. Simplified74.5%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    6. Step-by-step derivation
      1. sub-neg74.5%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) + \left(-\log \left(-y\right)\right)\right)} - z \]
      2. distribute-rgt-in74.7%

        \[\leadsto \color{blue}{\left(\log \left(-x\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right)} - z \]
      3. add-sqr-sqrt74.7%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{-x} \cdot \sqrt{-x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      4. sqrt-unprod25.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{\left(-x\right) \cdot \left(-x\right)}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      5. sqr-neg25.0%

        \[\leadsto \left(\log \left(\sqrt{\color{blue}{x \cdot x}}\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      6. sqrt-unprod0.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      7. add-sqr-sqrt0.0%

        \[\leadsto \left(\log \color{blue}{x} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      8. add-sqr-sqrt0.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{-y} \cdot \sqrt{-y}\right)}\right) \cdot x\right) - z \]
      9. sqrt-unprod0.6%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{\left(-y\right) \cdot \left(-y\right)}\right)}\right) \cdot x\right) - z \]
      10. sqr-neg0.6%

        \[\leadsto \left(\log x \cdot x + \left(-\log \left(\sqrt{\color{blue}{y \cdot y}}\right)\right) \cdot x\right) - z \]
      11. sqrt-unprod25.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{y} \cdot \sqrt{y}\right)}\right) \cdot x\right) - z \]
      12. add-sqr-sqrt25.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{y}\right) \cdot x\right) - z \]
    7. Applied egg-rr25.0%

      \[\leadsto \color{blue}{\left(\log x \cdot x + \left(-\log y\right) \cdot x\right)} - z \]
    8. Step-by-step derivation
      1. +-commutative25.0%

        \[\leadsto \color{blue}{\left(\left(-\log y\right) \cdot x + \log x \cdot x\right)} - z \]
      2. distribute-rgt-out25.0%

        \[\leadsto \color{blue}{x \cdot \left(\left(-\log y\right) + \log x\right)} - z \]
      3. neg-sub025.0%

        \[\leadsto x \cdot \left(\color{blue}{\left(0 - \log y\right)} + \log x\right) - z \]
      4. associate--r-25.0%

        \[\leadsto x \cdot \color{blue}{\left(0 - \left(\log y - \log x\right)\right)} - z \]
      5. log-div15.2%

        \[\leadsto x \cdot \left(0 - \color{blue}{\log \left(\frac{y}{x}\right)}\right) - z \]
      6. neg-sub015.2%

        \[\leadsto x \cdot \color{blue}{\left(-\log \left(\frac{y}{x}\right)\right)} - z \]
      7. distribute-rgt-neg-out15.2%

        \[\leadsto \color{blue}{\left(-x \cdot \log \left(\frac{y}{x}\right)\right)} - z \]
      8. distribute-lft-neg-in15.2%

        \[\leadsto \color{blue}{\left(-x\right) \cdot \log \left(\frac{y}{x}\right)} - z \]
      9. add-sqr-sqrt0.6%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\sqrt{\log \left(\frac{y}{x}\right)} \cdot \sqrt{\log \left(\frac{y}{x}\right)}\right)} - z \]
      10. sqrt-unprod0.7%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\sqrt{\log \left(\frac{y}{x}\right) \cdot \log \left(\frac{y}{x}\right)}} - z \]
      11. sqr-neg0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\color{blue}{\left(-\log \left(\frac{y}{x}\right)\right) \cdot \left(-\log \left(\frac{y}{x}\right)\right)}} - z \]
      12. neg-log0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\color{blue}{\log \left(\frac{1}{\frac{y}{x}}\right)} \cdot \left(-\log \left(\frac{y}{x}\right)\right)} - z \]
      13. clear-num0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\log \color{blue}{\left(\frac{x}{y}\right)} \cdot \left(-\log \left(\frac{y}{x}\right)\right)} - z \]
      14. neg-log0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\log \left(\frac{x}{y}\right) \cdot \color{blue}{\log \left(\frac{1}{\frac{y}{x}}\right)}} - z \]
      15. clear-num0.7%

        \[\leadsto \left(-x\right) \cdot \sqrt{\log \left(\frac{x}{y}\right) \cdot \log \color{blue}{\left(\frac{x}{y}\right)}} - z \]
      16. sqrt-unprod0.1%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\sqrt{\log \left(\frac{x}{y}\right)} \cdot \sqrt{\log \left(\frac{x}{y}\right)}\right)} - z \]
      17. add-sqr-sqrt0.6%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\log \left(\frac{x}{y}\right)} - z \]
      18. log-div20.9%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
      19. sub-neg20.9%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\left(\log x + \left(-\log y\right)\right)} - z \]
      20. add-log-exp20.9%

        \[\leadsto \left(-x\right) \cdot \left(\log x + \color{blue}{\log \left(e^{-\log y}\right)}\right) - z \]
      21. sum-log0.5%

        \[\leadsto \left(-x\right) \cdot \color{blue}{\log \left(x \cdot e^{-\log y}\right)} - z \]
    9. Applied egg-rr32.5%

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

    if -inf.0 < (*.f64 x (log.f64 (/.f64 x y))) < 5.00000000000000009e305

    1. Initial program 99.6%

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

    if 5.00000000000000009e305 < (*.f64 x (log.f64 (/.f64 x y)))

    1. Initial program 11.7%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in y around -inf 35.0%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{-1}{y}\right)\right)} - z \]
    4. Step-by-step derivation
      1. metadata-eval35.0%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{\color{blue}{-1}}{y}\right)\right) - z \]
      2. distribute-neg-frac35.0%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(-\frac{1}{y}\right)}\right) - z \]
      3. distribute-frac-neg235.0%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(\frac{1}{-y}\right)}\right) - z \]
      4. neg-mul-135.0%

        \[\leadsto x \cdot \left(\log \color{blue}{\left(-x\right)} + \log \left(\frac{1}{-y}\right)\right) - z \]
      5. log-rec35.0%

        \[\leadsto x \cdot \left(\log \left(-x\right) + \color{blue}{\left(-\log \left(-y\right)\right)}\right) - z \]
      6. sub-neg35.0%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    5. Simplified35.0%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    6. Step-by-step derivation
      1. sub-neg35.0%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) + \left(-\log \left(-y\right)\right)\right)} - z \]
      2. distribute-rgt-in35.0%

        \[\leadsto \color{blue}{\left(\log \left(-x\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right)} - z \]
      3. add-sqr-sqrt35.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{-x} \cdot \sqrt{-x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      4. sqrt-unprod8.1%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{\left(-x\right) \cdot \left(-x\right)}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      5. sqr-neg8.1%

        \[\leadsto \left(\log \left(\sqrt{\color{blue}{x \cdot x}}\right) \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      6. sqrt-unprod0.0%

        \[\leadsto \left(\log \color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      7. add-sqr-sqrt0.0%

        \[\leadsto \left(\log \color{blue}{x} \cdot x + \left(-\log \left(-y\right)\right) \cdot x\right) - z \]
      8. add-sqr-sqrt0.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{-y} \cdot \sqrt{-y}\right)}\right) \cdot x\right) - z \]
      9. sqrt-unprod24.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{\left(-y\right) \cdot \left(-y\right)}\right)}\right) \cdot x\right) - z \]
      10. sqr-neg24.0%

        \[\leadsto \left(\log x \cdot x + \left(-\log \left(\sqrt{\color{blue}{y \cdot y}}\right)\right) \cdot x\right) - z \]
      11. sqrt-unprod62.4%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{\left(\sqrt{y} \cdot \sqrt{y}\right)}\right) \cdot x\right) - z \]
      12. add-sqr-sqrt62.4%

        \[\leadsto \left(\log x \cdot x + \left(-\log \color{blue}{y}\right) \cdot x\right) - z \]
    7. Applied egg-rr62.4%

      \[\leadsto \color{blue}{\left(\log x \cdot x + \left(-\log y\right) \cdot x\right)} - z \]
    8. Step-by-step derivation
      1. distribute-rgt-out64.7%

        \[\leadsto \color{blue}{x \cdot \left(\log x + \left(-\log y\right)\right)} - z \]
      2. sub-neg64.7%

        \[\leadsto x \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
      3. log-div11.7%

        \[\leadsto x \cdot \color{blue}{\log \left(\frac{x}{y}\right)} - z \]
      4. *-commutative11.7%

        \[\leadsto \color{blue}{\log \left(\frac{x}{y}\right) \cdot x} - z \]
      5. log-div64.7%

        \[\leadsto \color{blue}{\left(\log x - \log y\right)} \cdot x - z \]
      6. sub-neg64.7%

        \[\leadsto \color{blue}{\left(\log x + \left(-\log y\right)\right)} \cdot x - z \]
      7. add-log-exp64.7%

        \[\leadsto \left(\log x + \color{blue}{\log \left(e^{-\log y}\right)}\right) \cdot x - z \]
      8. sum-log11.1%

        \[\leadsto \color{blue}{\log \left(x \cdot e^{-\log y}\right)} \cdot x - z \]
      9. add-sqr-sqrt6.1%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\sqrt{-\log y} \cdot \sqrt{-\log y}}}\right) \cdot x - z \]
      10. sqrt-unprod11.1%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\sqrt{\left(-\log y\right) \cdot \left(-\log y\right)}}}\right) \cdot x - z \]
      11. sqr-neg11.1%

        \[\leadsto \log \left(x \cdot e^{\sqrt{\color{blue}{\log y \cdot \log y}}}\right) \cdot x - z \]
      12. sqrt-unprod5.0%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\sqrt{\log y} \cdot \sqrt{\log y}}}\right) \cdot x - z \]
      13. add-sqr-sqrt16.7%

        \[\leadsto \log \left(x \cdot e^{\color{blue}{\log y}}\right) \cdot x - z \]
      14. add-exp-log49.3%

        \[\leadsto \log \left(x \cdot \color{blue}{y}\right) \cdot x - z \]
    9. Applied egg-rr49.3%

      \[\leadsto \color{blue}{\log \left(x \cdot y\right) \cdot x} - z \]
  3. Recombined 3 regimes into one program.
  4. Final simplification85.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \cdot \log \left(\frac{x}{y}\right) \leq -\infty:\\ \;\;\;\;\left(-x\right) \cdot \log \left(y \cdot x\right) - z\\ \mathbf{elif}\;x \cdot \log \left(\frac{x}{y}\right) \leq 5 \cdot 10^{+305}:\\ \;\;\;\;x \cdot \log \left(\frac{x}{y}\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \log \left(y \cdot x\right) - z\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 93.3% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -4.8 \cdot 10^{+142}:\\ \;\;\;\;x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)\\ \mathbf{elif}\;x \leq -5.8 \cdot 10^{-128}:\\ \;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\ \mathbf{elif}\;x \leq -5 \cdot 10^{-310}:\\ \;\;\;\;-z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(\log x - \log y\right) - z\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (if (<= x -4.8e+142)
   (* x (- (log (- x)) (log (- y))))
   (if (<= x -5.8e-128)
     (- (* x (log (* x (/ 1.0 y)))) z)
     (if (<= x -5e-310) (- z) (- (* x (- (log x) (log y))) z)))))
double code(double x, double y, double z) {
	double tmp;
	if (x <= -4.8e+142) {
		tmp = x * (log(-x) - log(-y));
	} else if (x <= -5.8e-128) {
		tmp = (x * log((x * (1.0 / y)))) - z;
	} else if (x <= -5e-310) {
		tmp = -z;
	} else {
		tmp = (x * (log(x) - log(y))) - z;
	}
	return tmp;
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8) :: tmp
    if (x <= (-4.8d+142)) then
        tmp = x * (log(-x) - log(-y))
    else if (x <= (-5.8d-128)) then
        tmp = (x * log((x * (1.0d0 / y)))) - z
    else if (x <= (-5d-310)) then
        tmp = -z
    else
        tmp = (x * (log(x) - log(y))) - z
    end if
    code = tmp
end function
public static double code(double x, double y, double z) {
	double tmp;
	if (x <= -4.8e+142) {
		tmp = x * (Math.log(-x) - Math.log(-y));
	} else if (x <= -5.8e-128) {
		tmp = (x * Math.log((x * (1.0 / y)))) - z;
	} else if (x <= -5e-310) {
		tmp = -z;
	} else {
		tmp = (x * (Math.log(x) - Math.log(y))) - z;
	}
	return tmp;
}
def code(x, y, z):
	tmp = 0
	if x <= -4.8e+142:
		tmp = x * (math.log(-x) - math.log(-y))
	elif x <= -5.8e-128:
		tmp = (x * math.log((x * (1.0 / y)))) - z
	elif x <= -5e-310:
		tmp = -z
	else:
		tmp = (x * (math.log(x) - math.log(y))) - z
	return tmp
function code(x, y, z)
	tmp = 0.0
	if (x <= -4.8e+142)
		tmp = Float64(x * Float64(log(Float64(-x)) - log(Float64(-y))));
	elseif (x <= -5.8e-128)
		tmp = Float64(Float64(x * log(Float64(x * Float64(1.0 / y)))) - z);
	elseif (x <= -5e-310)
		tmp = Float64(-z);
	else
		tmp = Float64(Float64(x * Float64(log(x) - log(y))) - z);
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	tmp = 0.0;
	if (x <= -4.8e+142)
		tmp = x * (log(-x) - log(-y));
	elseif (x <= -5.8e-128)
		tmp = (x * log((x * (1.0 / y)))) - z;
	elseif (x <= -5e-310)
		tmp = -z;
	else
		tmp = (x * (log(x) - log(y))) - z;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := If[LessEqual[x, -4.8e+142], N[(x * N[(N[Log[(-x)], $MachinePrecision] - N[Log[(-y)], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, -5.8e-128], N[(N[(x * N[Log[N[(x * N[(1.0 / y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], If[LessEqual[x, -5e-310], (-z), N[(N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -4.8 \cdot 10^{+142}:\\
\;\;\;\;x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)\\

\mathbf{elif}\;x \leq -5.8 \cdot 10^{-128}:\\
\;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\

\mathbf{elif}\;x \leq -5 \cdot 10^{-310}:\\
\;\;\;\;-z\\

\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if x < -4.7999999999999998e142

    1. Initial program 55.1%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in z around 0 54.2%

      \[\leadsto \color{blue}{x \cdot \log \left(\frac{x}{y}\right)} \]
    4. Taylor expanded in y around -inf 97.6%

      \[\leadsto \color{blue}{x \cdot \left(\log \left(-1 \cdot x\right) + \log \left(\frac{-1}{y}\right)\right)} \]
    5. Step-by-step derivation
      1. metadata-eval99.1%

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

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(-\frac{1}{y}\right)}\right) - z \]
      3. distribute-frac-neg299.1%

        \[\leadsto x \cdot \left(\log \left(-1 \cdot x\right) + \log \color{blue}{\left(\frac{1}{-y}\right)}\right) - z \]
      4. neg-mul-199.1%

        \[\leadsto x \cdot \left(\log \color{blue}{\left(-x\right)} + \log \left(\frac{1}{-y}\right)\right) - z \]
      5. log-rec99.1%

        \[\leadsto x \cdot \left(\log \left(-x\right) + \color{blue}{\left(-\log \left(-y\right)\right)}\right) - z \]
      6. sub-neg99.1%

        \[\leadsto x \cdot \color{blue}{\left(\log \left(-x\right) - \log \left(-y\right)\right)} - z \]
    6. Simplified97.6%

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

    if -4.7999999999999998e142 < x < -5.8000000000000001e-128

    1. Initial program 93.7%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. clear-num93.7%

        \[\leadsto x \cdot \log \color{blue}{\left(\frac{1}{\frac{y}{x}}\right)} - z \]
      2. associate-/r/93.7%

        \[\leadsto x \cdot \log \color{blue}{\left(\frac{1}{y} \cdot x\right)} - z \]
    4. Applied egg-rr93.7%

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

    if -5.8000000000000001e-128 < x < -4.999999999999985e-310

    1. Initial program 58.8%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 90.9%

      \[\leadsto \color{blue}{-1 \cdot z} \]
    4. Step-by-step derivation
      1. neg-mul-190.9%

        \[\leadsto \color{blue}{-z} \]
    5. Simplified90.9%

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

    if -4.999999999999985e-310 < x

    1. Initial program 78.5%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 99.5%

      \[\leadsto \color{blue}{x \cdot \left(\log x + \log \left(\frac{1}{y}\right)\right)} - z \]
    4. Step-by-step derivation
      1. log-rec99.5%

        \[\leadsto x \cdot \left(\log x + \color{blue}{\left(-\log y\right)}\right) - z \]
      2. neg-mul-199.5%

        \[\leadsto x \cdot \left(\log x + \color{blue}{-1 \cdot \log y}\right) - z \]
      3. neg-mul-199.5%

        \[\leadsto x \cdot \left(\log x + \color{blue}{\left(-\log y\right)}\right) - z \]
      4. sub-neg99.5%

        \[\leadsto x \cdot \color{blue}{\left(\log x - \log y\right)} - z \]
    5. Simplified99.5%

      \[\leadsto \color{blue}{x \cdot \left(\log x - \log y\right)} - z \]
  3. Recombined 4 regimes into one program.
  4. Final simplification96.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -4.8 \cdot 10^{+142}:\\ \;\;\;\;x \cdot \left(\log \left(-x\right) - \log \left(-y\right)\right)\\ \mathbf{elif}\;x \leq -5.8 \cdot 10^{-128}:\\ \;\;\;\;x \cdot \log \left(x \cdot \frac{1}{y}\right) - z\\ \mathbf{elif}\;x \leq -5 \cdot 10^{-310}:\\ \;\;\;\;-z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(\log x - \log y\right) - z\\ \end{array} \]
  5. Add Preprocessing

Alternative 9: 64.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -49000000000000 \lor \neg \left(z \leq 1.78 \cdot 10^{-155}\right):\\ \;\;\;\;-z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(-\log \left(\frac{y}{x}\right)\right)\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (if (or (<= z -49000000000000.0) (not (<= z 1.78e-155)))
   (- z)
   (* x (- (log (/ y x))))))
double code(double x, double y, double z) {
	double tmp;
	if ((z <= -49000000000000.0) || !(z <= 1.78e-155)) {
		tmp = -z;
	} else {
		tmp = x * -log((y / x));
	}
	return tmp;
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8) :: tmp
    if ((z <= (-49000000000000.0d0)) .or. (.not. (z <= 1.78d-155))) then
        tmp = -z
    else
        tmp = x * -log((y / x))
    end if
    code = tmp
end function
public static double code(double x, double y, double z) {
	double tmp;
	if ((z <= -49000000000000.0) || !(z <= 1.78e-155)) {
		tmp = -z;
	} else {
		tmp = x * -Math.log((y / x));
	}
	return tmp;
}
def code(x, y, z):
	tmp = 0
	if (z <= -49000000000000.0) or not (z <= 1.78e-155):
		tmp = -z
	else:
		tmp = x * -math.log((y / x))
	return tmp
function code(x, y, z)
	tmp = 0.0
	if ((z <= -49000000000000.0) || !(z <= 1.78e-155))
		tmp = Float64(-z);
	else
		tmp = Float64(x * Float64(-log(Float64(y / x))));
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	tmp = 0.0;
	if ((z <= -49000000000000.0) || ~((z <= 1.78e-155)))
		tmp = -z;
	else
		tmp = x * -log((y / x));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := If[Or[LessEqual[z, -49000000000000.0], N[Not[LessEqual[z, 1.78e-155]], $MachinePrecision]], (-z), N[(x * (-N[Log[N[(y / x), $MachinePrecision]], $MachinePrecision])), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -49000000000000 \lor \neg \left(z \leq 1.78 \cdot 10^{-155}\right):\\
\;\;\;\;-z\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -4.9e13 or 1.78e-155 < z

    1. Initial program 76.5%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 68.6%

      \[\leadsto \color{blue}{-1 \cdot z} \]
    4. Step-by-step derivation
      1. neg-mul-168.6%

        \[\leadsto \color{blue}{-z} \]
    5. Simplified68.6%

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

    if -4.9e13 < z < 1.78e-155

    1. Initial program 78.0%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. clear-num76.3%

        \[\leadsto x \cdot \log \color{blue}{\left(\frac{1}{\frac{y}{x}}\right)} - z \]
      2. neg-log79.8%

        \[\leadsto x \cdot \color{blue}{\left(-\log \left(\frac{y}{x}\right)\right)} - z \]
    4. Applied egg-rr79.8%

      \[\leadsto x \cdot \color{blue}{\left(-\log \left(\frac{y}{x}\right)\right)} - z \]
    5. Taylor expanded in z around 0 66.4%

      \[\leadsto \color{blue}{-1 \cdot \left(x \cdot \log \left(\frac{y}{x}\right)\right)} \]
    6. Step-by-step derivation
      1. associate-*r*66.4%

        \[\leadsto \color{blue}{\left(-1 \cdot x\right) \cdot \log \left(\frac{y}{x}\right)} \]
      2. neg-mul-166.4%

        \[\leadsto \color{blue}{\left(-x\right)} \cdot \log \left(\frac{y}{x}\right) \]
    7. Simplified66.4%

      \[\leadsto \color{blue}{\left(-x\right) \cdot \log \left(\frac{y}{x}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification67.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -49000000000000 \lor \neg \left(z \leq 1.78 \cdot 10^{-155}\right):\\ \;\;\;\;-z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(-\log \left(\frac{y}{x}\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 10: 64.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -130000000 \lor \neg \left(z \leq 1.78 \cdot 10^{-155}\right):\\ \;\;\;\;-z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \log \left(\frac{x}{y}\right)\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (if (or (<= z -130000000.0) (not (<= z 1.78e-155)))
   (- z)
   (* x (log (/ x y)))))
double code(double x, double y, double z) {
	double tmp;
	if ((z <= -130000000.0) || !(z <= 1.78e-155)) {
		tmp = -z;
	} else {
		tmp = x * log((x / y));
	}
	return tmp;
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8) :: tmp
    if ((z <= (-130000000.0d0)) .or. (.not. (z <= 1.78d-155))) then
        tmp = -z
    else
        tmp = x * log((x / y))
    end if
    code = tmp
end function
public static double code(double x, double y, double z) {
	double tmp;
	if ((z <= -130000000.0) || !(z <= 1.78e-155)) {
		tmp = -z;
	} else {
		tmp = x * Math.log((x / y));
	}
	return tmp;
}
def code(x, y, z):
	tmp = 0
	if (z <= -130000000.0) or not (z <= 1.78e-155):
		tmp = -z
	else:
		tmp = x * math.log((x / y))
	return tmp
function code(x, y, z)
	tmp = 0.0
	if ((z <= -130000000.0) || !(z <= 1.78e-155))
		tmp = Float64(-z);
	else
		tmp = Float64(x * log(Float64(x / y)));
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	tmp = 0.0;
	if ((z <= -130000000.0) || ~((z <= 1.78e-155)))
		tmp = -z;
	else
		tmp = x * log((x / y));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := If[Or[LessEqual[z, -130000000.0], N[Not[LessEqual[z, 1.78e-155]], $MachinePrecision]], (-z), N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -130000000 \lor \neg \left(z \leq 1.78 \cdot 10^{-155}\right):\\
\;\;\;\;-z\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -1.3e8 or 1.78e-155 < z

    1. Initial program 76.5%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0 68.6%

      \[\leadsto \color{blue}{-1 \cdot z} \]
    4. Step-by-step derivation
      1. neg-mul-168.6%

        \[\leadsto \color{blue}{-z} \]
    5. Simplified68.6%

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

    if -1.3e8 < z < 1.78e-155

    1. Initial program 78.0%

      \[x \cdot \log \left(\frac{x}{y}\right) - z \]
    2. Add Preprocessing
    3. Taylor expanded in z around 0 63.7%

      \[\leadsto \color{blue}{x \cdot \log \left(\frac{x}{y}\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification66.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -130000000 \lor \neg \left(z \leq 1.78 \cdot 10^{-155}\right):\\ \;\;\;\;-z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \log \left(\frac{x}{y}\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 11: 49.9% accurate, 53.5× speedup?

\[\begin{array}{l} \\ -z \end{array} \]
(FPCore (x y z) :precision binary64 (- z))
double code(double x, double y, double z) {
	return -z;
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    code = -z
end function
public static double code(double x, double y, double z) {
	return -z;
}
def code(x, y, z):
	return -z
function code(x, y, z)
	return Float64(-z)
end
function tmp = code(x, y, z)
	tmp = -z;
end
code[x_, y_, z_] := (-z)
\begin{array}{l}

\\
-z
\end{array}
Derivation
  1. Initial program 77.1%

    \[x \cdot \log \left(\frac{x}{y}\right) - z \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0 48.8%

    \[\leadsto \color{blue}{-1 \cdot z} \]
  4. Step-by-step derivation
    1. neg-mul-148.8%

      \[\leadsto \color{blue}{-z} \]
  5. Simplified48.8%

    \[\leadsto \color{blue}{-z} \]
  6. Add Preprocessing

Alternative 12: 2.3% accurate, 107.0× speedup?

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

\\
z
\end{array}
Derivation
  1. Initial program 77.1%

    \[x \cdot \log \left(\frac{x}{y}\right) - z \]
  2. Add Preprocessing
  3. Taylor expanded in x around 0 48.8%

    \[\leadsto \color{blue}{-1 \cdot z} \]
  4. Step-by-step derivation
    1. neg-mul-148.8%

      \[\leadsto \color{blue}{-z} \]
  5. Simplified48.8%

    \[\leadsto \color{blue}{-z} \]
  6. Step-by-step derivation
    1. neg-sub048.8%

      \[\leadsto \color{blue}{0 - z} \]
    2. sub-neg48.8%

      \[\leadsto \color{blue}{0 + \left(-z\right)} \]
    3. add-sqr-sqrt23.3%

      \[\leadsto 0 + \color{blue}{\sqrt{-z} \cdot \sqrt{-z}} \]
    4. sqrt-unprod15.1%

      \[\leadsto 0 + \color{blue}{\sqrt{\left(-z\right) \cdot \left(-z\right)}} \]
    5. sqr-neg15.1%

      \[\leadsto 0 + \sqrt{\color{blue}{z \cdot z}} \]
    6. sqrt-unprod1.2%

      \[\leadsto 0 + \color{blue}{\sqrt{z} \cdot \sqrt{z}} \]
    7. add-sqr-sqrt2.3%

      \[\leadsto 0 + \color{blue}{z} \]
  7. Applied egg-rr2.3%

    \[\leadsto \color{blue}{0 + z} \]
  8. Step-by-step derivation
    1. +-lft-identity2.3%

      \[\leadsto \color{blue}{z} \]
  9. Simplified2.3%

    \[\leadsto \color{blue}{z} \]
  10. Add Preprocessing

Developer Target 1: 88.6% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y < 7.595077799083773 \cdot 10^{-308}:\\ \;\;\;\;x \cdot \log \left(\frac{x}{y}\right) - z\\ \mathbf{else}:\\ \;\;\;\;x \cdot \left(\log x - \log y\right) - z\\ \end{array} \end{array} \]
(FPCore (x y z)
 :precision binary64
 (if (< y 7.595077799083773e-308)
   (- (* x (log (/ x y))) z)
   (- (* x (- (log x) (log y))) z)))
double code(double x, double y, double z) {
	double tmp;
	if (y < 7.595077799083773e-308) {
		tmp = (x * log((x / y))) - z;
	} else {
		tmp = (x * (log(x) - log(y))) - z;
	}
	return tmp;
}
real(8) function code(x, y, z)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8) :: tmp
    if (y < 7.595077799083773d-308) then
        tmp = (x * log((x / y))) - z
    else
        tmp = (x * (log(x) - log(y))) - z
    end if
    code = tmp
end function
public static double code(double x, double y, double z) {
	double tmp;
	if (y < 7.595077799083773e-308) {
		tmp = (x * Math.log((x / y))) - z;
	} else {
		tmp = (x * (Math.log(x) - Math.log(y))) - z;
	}
	return tmp;
}
def code(x, y, z):
	tmp = 0
	if y < 7.595077799083773e-308:
		tmp = (x * math.log((x / y))) - z
	else:
		tmp = (x * (math.log(x) - math.log(y))) - z
	return tmp
function code(x, y, z)
	tmp = 0.0
	if (y < 7.595077799083773e-308)
		tmp = Float64(Float64(x * log(Float64(x / y))) - z);
	else
		tmp = Float64(Float64(x * Float64(log(x) - log(y))) - z);
	end
	return tmp
end
function tmp_2 = code(x, y, z)
	tmp = 0.0;
	if (y < 7.595077799083773e-308)
		tmp = (x * log((x / y))) - z;
	else
		tmp = (x * (log(x) - log(y))) - z;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_] := If[Less[y, 7.595077799083773e-308], N[(N[(x * N[Log[N[(x / y), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision], N[(N[(x * N[(N[Log[x], $MachinePrecision] - N[Log[y], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - z), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y < 7.595077799083773 \cdot 10^{-308}:\\
\;\;\;\;x \cdot \log \left(\frac{x}{y}\right) - z\\

\mathbf{else}:\\
\;\;\;\;x \cdot \left(\log x - \log y\right) - z\\


\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2024139 
(FPCore (x y z)
  :name "Numeric.SpecFunctions.Extra:bd0 from math-functions-0.1.5.2"
  :precision binary64

  :alt
  (! :herbie-platform default (if (< y 7595077799083773/100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000) (- (* x (log (/ x y))) z) (- (* x (- (log x) (log y))) z)))

  (- (* x (log (/ x y))) z))