System.Random.MWC.Distributions:truncatedExp from mwc-random-0.13.3.2

Percentage Accurate: 61.4% → 98.5%
Time: 28.4s
Alternatives: 10
Speedup: 211.0×

Specification

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

\\
x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t}
\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 10 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: 61.4% accurate, 1.0× speedup?

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

\\
x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t}
\end{array}

Alternative 1: 98.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t} \end{array} \]
(FPCore (x y z t) :precision binary64 (- x (/ (log1p (* y (expm1 z))) t)))
double code(double x, double y, double z, double t) {
	return x - (log1p((y * expm1(z))) / t);
}
public static double code(double x, double y, double z, double t) {
	return x - (Math.log1p((y * Math.expm1(z))) / t);
}
def code(x, y, z, t):
	return x - (math.log1p((y * math.expm1(z))) / t)
function code(x, y, z, t)
	return Float64(x - Float64(log1p(Float64(y * expm1(z))) / t))
end
code[x_, y_, z_, t_] := N[(x - N[(N[Log[1 + N[(y * N[(Exp[z] - 1), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}
\end{array}
Derivation
  1. Initial program 59.4%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. associate-+l-71.8%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
    2. sub-neg71.8%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
    3. log1p-define78.9%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
    4. neg-sub078.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
    5. associate-+l-78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
    6. neg-sub078.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
    7. +-commutative78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    8. unsub-neg78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
    9. *-rgt-identity78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    10. distribute-lft-out--78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    11. expm1-define98.6%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
  4. Add Preprocessing
  5. Final simplification98.6%

    \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t} \]
  6. Add Preprocessing

Alternative 2: 91.6% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -1.7 \cdot 10^{-7}:\\ \;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + z \cdot \left(y \cdot 0.5\right)\right)\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -1.7e-7)
   (- x (/ (* y (expm1 z)) t))
   (- x (/ (log1p (* z (+ y (* z (* y 0.5))))) t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -1.7e-7) {
		tmp = x - ((y * expm1(z)) / t);
	} else {
		tmp = x - (log1p((z * (y + (z * (y * 0.5))))) / t);
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -1.7e-7) {
		tmp = x - ((y * Math.expm1(z)) / t);
	} else {
		tmp = x - (Math.log1p((z * (y + (z * (y * 0.5))))) / t);
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -1.7e-7:
		tmp = x - ((y * math.expm1(z)) / t)
	else:
		tmp = x - (math.log1p((z * (y + (z * (y * 0.5))))) / t)
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -1.7e-7)
		tmp = Float64(x - Float64(Float64(y * expm1(z)) / t));
	else
		tmp = Float64(x - Float64(log1p(Float64(z * Float64(y + Float64(z * Float64(y * 0.5))))) / t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[z, -1.7e-7], N[(x - N[(N[(y * N[(Exp[z] - 1), $MachinePrecision]), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[Log[1 + N[(z * N[(y + N[(z * N[(y * 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -1.7 \cdot 10^{-7}:\\
\;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\

\mathbf{else}:\\
\;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + z \cdot \left(y \cdot 0.5\right)\right)\right)}{t}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -1.69999999999999987e-7

    1. Initial program 75.3%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-75.3%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg75.3%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define99.6%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub099.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub099.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--99.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in y around 0 81.6%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
    6. Step-by-step derivation
      1. expm1-define82.1%

        \[\leadsto x - \frac{y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
    7. Simplified82.1%

      \[\leadsto x - \color{blue}{\frac{y \cdot \mathsf{expm1}\left(z\right)}{t}} \]

    if -1.69999999999999987e-7 < z

    1. Initial program 52.8%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-70.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg70.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define70.4%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub070.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub070.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define98.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified98.1%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in z around 0 98.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{z \cdot \left(y + 0.5 \cdot \left(y \cdot z\right)\right)}\right)}{t} \]
    6. Step-by-step derivation
      1. associate-*r*98.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \color{blue}{\left(0.5 \cdot y\right) \cdot z}\right)\right)}{t} \]
      2. *-commutative98.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \color{blue}{\left(y \cdot 0.5\right)} \cdot z\right)\right)}{t} \]
    7. Simplified98.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{z \cdot \left(y + \left(y \cdot 0.5\right) \cdot z\right)}\right)}{t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification93.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -1.7 \cdot 10^{-7}:\\ \;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + z \cdot \left(y \cdot 0.5\right)\right)\right)}{t}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 86.2% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -7.5 \cdot 10^{+253}:\\ \;\;\;\;\frac{\mathsf{log1p}\left(y \cdot z\right)}{-t}\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= y -7.5e+253) (/ (log1p (* y z)) (- t)) (- x (* y (/ (expm1 z) t)))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (y <= -7.5e+253) {
		tmp = log1p((y * z)) / -t;
	} else {
		tmp = x - (y * (expm1(z) / t));
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (y <= -7.5e+253) {
		tmp = Math.log1p((y * z)) / -t;
	} else {
		tmp = x - (y * (Math.expm1(z) / t));
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if y <= -7.5e+253:
		tmp = math.log1p((y * z)) / -t
	else:
		tmp = x - (y * (math.expm1(z) / t))
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (y <= -7.5e+253)
		tmp = Float64(log1p(Float64(y * z)) / Float64(-t));
	else
		tmp = Float64(x - Float64(y * Float64(expm1(z) / t)));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[y, -7.5e+253], N[(N[Log[1 + N[(y * z), $MachinePrecision]], $MachinePrecision] / (-t)), $MachinePrecision], N[(x - N[(y * N[(N[(Exp[z] - 1), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -7.5 \cdot 10^{+253}:\\
\;\;\;\;\frac{\mathsf{log1p}\left(y \cdot z\right)}{-t}\\

\mathbf{else}:\\
\;\;\;\;x - y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -7.50000000000000017e253

    1. Initial program 34.9%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-51.6%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg51.6%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define51.6%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub051.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-51.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub051.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative51.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg51.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity51.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--51.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define99.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.4%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in z around 0 69.0%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
    6. Taylor expanded in x around 0 54.2%

      \[\leadsto \color{blue}{-1 \cdot \frac{\log \left(1 + y \cdot z\right)}{t}} \]
    7. Step-by-step derivation
      1. mul-1-neg54.2%

        \[\leadsto \color{blue}{-\frac{\log \left(1 + y \cdot z\right)}{t}} \]
      2. log1p-define54.2%

        \[\leadsto -\frac{\color{blue}{\mathsf{log1p}\left(y \cdot z\right)}}{t} \]
      3. distribute-frac-neg254.2%

        \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(y \cdot z\right)}{-t}} \]
    8. Simplified54.2%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(y \cdot z\right)}{-t}} \]

    if -7.50000000000000017e253 < y

    1. Initial program 60.7%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-72.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg72.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define80.4%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub080.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-80.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub080.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative80.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg80.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity80.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--80.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define98.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified98.6%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in y around 0 76.1%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
    6. Step-by-step derivation
      1. associate-/l*76.0%

        \[\leadsto x - \color{blue}{y \cdot \frac{e^{z} - 1}{t}} \]
      2. expm1-define91.8%

        \[\leadsto x - y \cdot \frac{\color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
    7. Simplified91.8%

      \[\leadsto x - \color{blue}{y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification89.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -7.5 \cdot 10^{+253}:\\ \;\;\;\;\frac{\mathsf{log1p}\left(y \cdot z\right)}{-t}\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 91.5% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -1.32 \cdot 10^{-8}:\\ \;\;\;\;x - y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -1.32e-8) (- x (* y (/ (expm1 z) t))) (- x (/ (log1p (* y z)) t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -1.32e-8) {
		tmp = x - (y * (expm1(z) / t));
	} else {
		tmp = x - (log1p((y * z)) / t);
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -1.32e-8) {
		tmp = x - (y * (Math.expm1(z) / t));
	} else {
		tmp = x - (Math.log1p((y * z)) / t);
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -1.32e-8:
		tmp = x - (y * (math.expm1(z) / t))
	else:
		tmp = x - (math.log1p((y * z)) / t)
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -1.32e-8)
		tmp = Float64(x - Float64(y * Float64(expm1(z) / t)));
	else
		tmp = Float64(x - Float64(log1p(Float64(y * z)) / t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[z, -1.32e-8], N[(x - N[(y * N[(N[(Exp[z] - 1), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[Log[1 + N[(y * z), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -1.32 \cdot 10^{-8}:\\
\;\;\;\;x - y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}\\

\mathbf{else}:\\
\;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -1.32000000000000007e-8

    1. Initial program 75.3%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-75.3%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg75.3%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define99.6%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub099.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub099.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--99.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in y around 0 81.6%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
    6. Step-by-step derivation
      1. associate-/l*81.5%

        \[\leadsto x - \color{blue}{y \cdot \frac{e^{z} - 1}{t}} \]
      2. expm1-define82.0%

        \[\leadsto x - y \cdot \frac{\color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
    7. Simplified82.0%

      \[\leadsto x - \color{blue}{y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}} \]

    if -1.32000000000000007e-8 < z

    1. Initial program 52.8%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-70.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg70.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define70.4%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub070.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub070.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define98.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified98.1%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in z around 0 98.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification93.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -1.32 \cdot 10^{-8}:\\ \;\;\;\;x - y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 91.4% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -6.5 \cdot 10^{-12}:\\ \;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -6.5e-12) (- x (/ (* y (expm1 z)) t)) (- x (/ (log1p (* y z)) t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -6.5e-12) {
		tmp = x - ((y * expm1(z)) / t);
	} else {
		tmp = x - (log1p((y * z)) / t);
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -6.5e-12) {
		tmp = x - ((y * Math.expm1(z)) / t);
	} else {
		tmp = x - (Math.log1p((y * z)) / t);
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -6.5e-12:
		tmp = x - ((y * math.expm1(z)) / t)
	else:
		tmp = x - (math.log1p((y * z)) / t)
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -6.5e-12)
		tmp = Float64(x - Float64(Float64(y * expm1(z)) / t));
	else
		tmp = Float64(x - Float64(log1p(Float64(y * z)) / t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[z, -6.5e-12], N[(x - N[(N[(y * N[(Exp[z] - 1), $MachinePrecision]), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[Log[1 + N[(y * z), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -6.5 \cdot 10^{-12}:\\
\;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\

\mathbf{else}:\\
\;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -6.5000000000000002e-12

    1. Initial program 75.3%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-75.3%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg75.3%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define99.6%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub099.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub099.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--99.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in y around 0 81.6%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
    6. Step-by-step derivation
      1. expm1-define82.1%

        \[\leadsto x - \frac{y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
    7. Simplified82.1%

      \[\leadsto x - \color{blue}{\frac{y \cdot \mathsf{expm1}\left(z\right)}{t}} \]

    if -6.5000000000000002e-12 < z

    1. Initial program 52.8%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-70.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg70.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define70.4%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub070.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub070.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--70.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define98.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified98.1%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in z around 0 98.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification93.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -6.5 \cdot 10^{-12}:\\ \;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 82.2% accurate, 10.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -8000000000000:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \left(z \cdot \left(0.5 \cdot \frac{z}{t} + \frac{1}{t}\right)\right)\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -8000000000000.0)
   x
   (- x (* y (* z (+ (* 0.5 (/ z t)) (/ 1.0 t)))))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -8000000000000.0) {
		tmp = x;
	} else {
		tmp = x - (y * (z * ((0.5 * (z / t)) + (1.0 / t))));
	}
	return tmp;
}
real(8) function code(x, y, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8) :: tmp
    if (z <= (-8000000000000.0d0)) then
        tmp = x
    else
        tmp = x - (y * (z * ((0.5d0 * (z / t)) + (1.0d0 / t))))
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -8000000000000.0) {
		tmp = x;
	} else {
		tmp = x - (y * (z * ((0.5 * (z / t)) + (1.0 / t))));
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -8000000000000.0:
		tmp = x
	else:
		tmp = x - (y * (z * ((0.5 * (z / t)) + (1.0 / t))))
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -8000000000000.0)
		tmp = x;
	else
		tmp = Float64(x - Float64(y * Float64(z * Float64(Float64(0.5 * Float64(z / t)) + Float64(1.0 / t)))));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t)
	tmp = 0.0;
	if (z <= -8000000000000.0)
		tmp = x;
	else
		tmp = x - (y * (z * ((0.5 * (z / t)) + (1.0 / t))));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[z, -8000000000000.0], x, N[(x - N[(y * N[(z * N[(N[(0.5 * N[(z / t), $MachinePrecision]), $MachinePrecision] + N[(1.0 / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -8000000000000:\\
\;\;\;\;x\\

\mathbf{else}:\\
\;\;\;\;x - y \cdot \left(z \cdot \left(0.5 \cdot \frac{z}{t} + \frac{1}{t}\right)\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -8e12

    1. Initial program 74.5%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-74.5%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg74.5%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define100.0%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub0100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub0100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around inf 57.8%

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

    if -8e12 < z

    1. Initial program 53.8%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-70.8%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg70.8%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define71.2%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub071.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-71.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub071.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative71.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg71.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity71.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--71.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define98.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified98.1%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in z around 0 77.6%

      \[\leadsto x - \color{blue}{z \cdot \left(0.5 \cdot \frac{z \cdot \left(y + -1 \cdot {y}^{2}\right)}{t} + \frac{y}{t}\right)} \]
    6. Taylor expanded in y around 0 90.4%

      \[\leadsto x - \color{blue}{y \cdot \left(z \cdot \left(0.5 \cdot \frac{z}{t} + \frac{1}{t}\right)\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification81.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -8000000000000:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \left(z \cdot \left(0.5 \cdot \frac{z}{t} + \frac{1}{t}\right)\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 82.4% accurate, 10.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -3.9 \cdot 10^{+63}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x + \frac{-1}{\frac{0.5 \cdot \left(y \cdot t\right) + \frac{t}{z}}{y}}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -3.9e+63) x (+ x (/ -1.0 (/ (+ (* 0.5 (* y t)) (/ t z)) y)))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -3.9e+63) {
		tmp = x;
	} else {
		tmp = x + (-1.0 / (((0.5 * (y * t)) + (t / z)) / y));
	}
	return tmp;
}
real(8) function code(x, y, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8) :: tmp
    if (z <= (-3.9d+63)) then
        tmp = x
    else
        tmp = x + ((-1.0d0) / (((0.5d0 * (y * t)) + (t / z)) / y))
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -3.9e+63) {
		tmp = x;
	} else {
		tmp = x + (-1.0 / (((0.5 * (y * t)) + (t / z)) / y));
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -3.9e+63:
		tmp = x
	else:
		tmp = x + (-1.0 / (((0.5 * (y * t)) + (t / z)) / y))
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -3.9e+63)
		tmp = x;
	else
		tmp = Float64(x + Float64(-1.0 / Float64(Float64(Float64(0.5 * Float64(y * t)) + Float64(t / z)) / y)));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t)
	tmp = 0.0;
	if (z <= -3.9e+63)
		tmp = x;
	else
		tmp = x + (-1.0 / (((0.5 * (y * t)) + (t / z)) / y));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[z, -3.9e+63], x, N[(x + N[(-1.0 / N[(N[(N[(0.5 * N[(y * t), $MachinePrecision]), $MachinePrecision] + N[(t / z), $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -3.9 \cdot 10^{+63}:\\
\;\;\;\;x\\

\mathbf{else}:\\
\;\;\;\;x + \frac{-1}{\frac{0.5 \cdot \left(y \cdot t\right) + \frac{t}{z}}{y}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -3.9e63

    1. Initial program 73.9%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-73.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg73.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define100.0%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub0100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub0100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around inf 58.0%

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

    if -3.9e63 < z

    1. Initial program 54.9%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-71.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg71.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define72.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub072.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub072.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define98.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified98.2%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in z around 0 96.3%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
    6. Step-by-step derivation
      1. clear-num96.2%

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot z\right)}}} \]
      2. inv-pow96.2%

        \[\leadsto x - \color{blue}{{\left(\frac{t}{\mathsf{log1p}\left(y \cdot z\right)}\right)}^{-1}} \]
    7. Applied egg-rr96.2%

      \[\leadsto x - \color{blue}{{\left(\frac{t}{\mathsf{log1p}\left(y \cdot z\right)}\right)}^{-1}} \]
    8. Step-by-step derivation
      1. unpow-196.2%

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot z\right)}}} \]
    9. Simplified96.2%

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot z\right)}}} \]
    10. Taylor expanded in y around 0 89.6%

      \[\leadsto x - \frac{1}{\color{blue}{\frac{0.5 \cdot \left(t \cdot y\right) + \frac{t}{z}}{y}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification82.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -3.9 \cdot 10^{+63}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x + \frac{-1}{\frac{0.5 \cdot \left(y \cdot t\right) + \frac{t}{z}}{y}}\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 70.6% accurate, 13.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq -1.9 \cdot 10^{-197}:\\ \;\;\;\;x\\ \mathbf{elif}\;t \leq 5 \cdot 10^{-253}:\\ \;\;\;\;\frac{z}{t} \cdot \left(-y\right)\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= t -1.9e-197) x (if (<= t 5e-253) (* (/ z t) (- y)) x)))
double code(double x, double y, double z, double t) {
	double tmp;
	if (t <= -1.9e-197) {
		tmp = x;
	} else if (t <= 5e-253) {
		tmp = (z / t) * -y;
	} else {
		tmp = x;
	}
	return tmp;
}
real(8) function code(x, y, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8) :: tmp
    if (t <= (-1.9d-197)) then
        tmp = x
    else if (t <= 5d-253) then
        tmp = (z / t) * -y
    else
        tmp = x
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (t <= -1.9e-197) {
		tmp = x;
	} else if (t <= 5e-253) {
		tmp = (z / t) * -y;
	} else {
		tmp = x;
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if t <= -1.9e-197:
		tmp = x
	elif t <= 5e-253:
		tmp = (z / t) * -y
	else:
		tmp = x
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (t <= -1.9e-197)
		tmp = x;
	elseif (t <= 5e-253)
		tmp = Float64(Float64(z / t) * Float64(-y));
	else
		tmp = x;
	end
	return tmp
end
function tmp_2 = code(x, y, z, t)
	tmp = 0.0;
	if (t <= -1.9e-197)
		tmp = x;
	elseif (t <= 5e-253)
		tmp = (z / t) * -y;
	else
		tmp = x;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[t, -1.9e-197], x, If[LessEqual[t, 5e-253], N[(N[(z / t), $MachinePrecision] * (-y)), $MachinePrecision], x]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq -1.9 \cdot 10^{-197}:\\
\;\;\;\;x\\

\mathbf{elif}\;t \leq 5 \cdot 10^{-253}:\\
\;\;\;\;\frac{z}{t} \cdot \left(-y\right)\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < -1.8999999999999999e-197 or 4.99999999999999971e-253 < t

    1. Initial program 66.6%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-81.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg81.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define87.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub087.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-87.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub087.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative87.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg87.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity87.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--87.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define99.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.5%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around inf 76.7%

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

    if -1.8999999999999999e-197 < t < 4.99999999999999971e-253

    1. Initial program 25.2%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-27.7%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg27.7%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define39.0%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub039.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-39.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub039.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative39.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg39.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity39.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--38.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define94.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified94.7%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in z around 0 68.8%

      \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
    6. Step-by-step derivation
      1. associate-/l*73.6%

        \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
    7. Simplified73.6%

      \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
    8. Taylor expanded in x around 0 49.5%

      \[\leadsto \color{blue}{-1 \cdot \frac{y \cdot z}{t}} \]
    9. Step-by-step derivation
      1. neg-mul-149.5%

        \[\leadsto \color{blue}{-\frac{y \cdot z}{t}} \]
      2. associate-/l*53.5%

        \[\leadsto -\color{blue}{y \cdot \frac{z}{t}} \]
      3. distribute-rgt-neg-in53.5%

        \[\leadsto \color{blue}{y \cdot \left(-\frac{z}{t}\right)} \]
      4. distribute-frac-neg53.5%

        \[\leadsto y \cdot \color{blue}{\frac{-z}{t}} \]
    10. Simplified53.5%

      \[\leadsto \color{blue}{y \cdot \frac{-z}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification72.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq -1.9 \cdot 10^{-197}:\\ \;\;\;\;x\\ \mathbf{elif}\;t \leq 5 \cdot 10^{-253}:\\ \;\;\;\;\frac{z}{t} \cdot \left(-y\right)\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]
  5. Add Preprocessing

Alternative 9: 81.7% accurate, 17.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -2.7 \cdot 10^{+63}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{z}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -2.7e+63) x (- x (* y (/ z t)))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -2.7e+63) {
		tmp = x;
	} else {
		tmp = x - (y * (z / t));
	}
	return tmp;
}
real(8) function code(x, y, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8) :: tmp
    if (z <= (-2.7d+63)) then
        tmp = x
    else
        tmp = x - (y * (z / t))
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -2.7e+63) {
		tmp = x;
	} else {
		tmp = x - (y * (z / t));
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -2.7e+63:
		tmp = x
	else:
		tmp = x - (y * (z / t))
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -2.7e+63)
		tmp = x;
	else
		tmp = Float64(x - Float64(y * Float64(z / t)));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t)
	tmp = 0.0;
	if (z <= -2.7e+63)
		tmp = x;
	else
		tmp = x - (y * (z / t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[z, -2.7e+63], x, N[(x - N[(y * N[(z / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -2.7 \cdot 10^{+63}:\\
\;\;\;\;x\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -2.70000000000000017e63

    1. Initial program 73.9%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-73.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg73.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define100.0%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub0100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub0100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define100.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in x around inf 58.0%

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

    if -2.70000000000000017e63 < z

    1. Initial program 54.9%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-71.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg71.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define72.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub072.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub072.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--72.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define98.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified98.2%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in z around 0 87.4%

      \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
    6. Step-by-step derivation
      1. associate-/l*88.8%

        \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
    7. Simplified88.8%

      \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification81.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -2.7 \cdot 10^{+63}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{z}{t}\\ \end{array} \]
  5. Add Preprocessing

Alternative 10: 71.4% accurate, 211.0× speedup?

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

\\
x
\end{array}
Derivation
  1. Initial program 59.4%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. associate-+l-71.8%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
    2. sub-neg71.8%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
    3. log1p-define78.9%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
    4. neg-sub078.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
    5. associate-+l-78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
    6. neg-sub078.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
    7. +-commutative78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    8. unsub-neg78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
    9. *-rgt-identity78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    10. distribute-lft-out--78.9%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    11. expm1-define98.6%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified98.6%

    \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
  4. Add Preprocessing
  5. Taylor expanded in x around inf 67.2%

    \[\leadsto \color{blue}{x} \]
  6. Final simplification67.2%

    \[\leadsto x \]
  7. Add Preprocessing

Developer target: 73.9% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_1 := \frac{-0.5}{y \cdot t}\\ \mathbf{if}\;z < -2.8874623088207947 \cdot 10^{+119}:\\ \;\;\;\;\left(x - \frac{t\_1}{z \cdot z}\right) - t\_1 \cdot \frac{\frac{2}{z}}{z \cdot z}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\log \left(1 + z \cdot y\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (let* ((t_1 (/ (- 0.5) (* y t))))
   (if (< z -2.8874623088207947e+119)
     (- (- x (/ t_1 (* z z))) (* t_1 (/ (/ 2.0 z) (* z z))))
     (- x (/ (log (+ 1.0 (* z y))) t)))))
double code(double x, double y, double z, double t) {
	double t_1 = -0.5 / (y * t);
	double tmp;
	if (z < -2.8874623088207947e+119) {
		tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0 / z) / (z * z)));
	} else {
		tmp = x - (log((1.0 + (z * y))) / t);
	}
	return tmp;
}
real(8) function code(x, y, z, t)
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    real(8) :: t_1
    real(8) :: tmp
    t_1 = -0.5d0 / (y * t)
    if (z < (-2.8874623088207947d+119)) then
        tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0d0 / z) / (z * z)))
    else
        tmp = x - (log((1.0d0 + (z * y))) / t)
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t) {
	double t_1 = -0.5 / (y * t);
	double tmp;
	if (z < -2.8874623088207947e+119) {
		tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0 / z) / (z * z)));
	} else {
		tmp = x - (Math.log((1.0 + (z * y))) / t);
	}
	return tmp;
}
def code(x, y, z, t):
	t_1 = -0.5 / (y * t)
	tmp = 0
	if z < -2.8874623088207947e+119:
		tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0 / z) / (z * z)))
	else:
		tmp = x - (math.log((1.0 + (z * y))) / t)
	return tmp
function code(x, y, z, t)
	t_1 = Float64(Float64(-0.5) / Float64(y * t))
	tmp = 0.0
	if (z < -2.8874623088207947e+119)
		tmp = Float64(Float64(x - Float64(t_1 / Float64(z * z))) - Float64(t_1 * Float64(Float64(2.0 / z) / Float64(z * z))));
	else
		tmp = Float64(x - Float64(log(Float64(1.0 + Float64(z * y))) / t));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t)
	t_1 = -0.5 / (y * t);
	tmp = 0.0;
	if (z < -2.8874623088207947e+119)
		tmp = (x - (t_1 / (z * z))) - (t_1 * ((2.0 / z) / (z * z)));
	else
		tmp = x - (log((1.0 + (z * y))) / t);
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := Block[{t$95$1 = N[((-0.5) / N[(y * t), $MachinePrecision]), $MachinePrecision]}, If[Less[z, -2.8874623088207947e+119], N[(N[(x - N[(t$95$1 / N[(z * z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(t$95$1 * N[(N[(2.0 / z), $MachinePrecision] / N[(z * z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[Log[N[(1.0 + N[(z * y), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_1 := \frac{-0.5}{y \cdot t}\\
\mathbf{if}\;z < -2.8874623088207947 \cdot 10^{+119}:\\
\;\;\;\;\left(x - \frac{t\_1}{z \cdot z}\right) - t\_1 \cdot \frac{\frac{2}{z}}{z \cdot z}\\

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


\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2024055 
(FPCore (x y z t)
  :name "System.Random.MWC.Distributions:truncatedExp from mwc-random-0.13.3.2"
  :precision binary64

  :alt
  (if (< z -2.8874623088207947e+119) (- (- x (/ (/ (- 0.5) (* y t)) (* z z))) (* (/ (- 0.5) (* y t)) (/ (/ 2.0 z) (* z z)))) (- x (/ (log (+ 1.0 (* z y))) t)))

  (- x (/ (log (+ (- 1.0 y) (* y (exp z)))) t)))