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

Percentage Accurate: 61.3% → 98.2%
Time: 19.8s
Alternatives: 9
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 9 alternatives:

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

Initial Program: 61.3% 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: 98.2% 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 61.9%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. associate-+l-81.9%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
    2. sub-neg81.9%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
    3. log1p-define86.8%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
    4. neg-sub086.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
    5. associate-+l-86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
    6. neg-sub086.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
    7. +-commutative86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    8. unsub-neg86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
    9. *-rgt-identity86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    10. distribute-lft-out--86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    11. expm1-define98.7%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified98.7%

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

Alternative 2: 93.0% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -50000000000000:\\ \;\;\;\;x \cdot \left(1 + \frac{1}{t \cdot \frac{\frac{x}{1 - e^{z}} - 0.5 \cdot \left(x \cdot y\right)}{y}}\right)\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + z \cdot 0.16666666666666666\right)\right)\right)\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -50000000000000.0)
   (* x (+ 1.0 (/ 1.0 (* t (/ (- (/ x (- 1.0 (exp z))) (* 0.5 (* x y))) y)))))
   (-
    x
    (/ (log1p (* z (+ y (* y (* z (+ 0.5 (* z 0.16666666666666666))))))) t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -50000000000000.0) {
		tmp = x * (1.0 + (1.0 / (t * (((x / (1.0 - exp(z))) - (0.5 * (x * y))) / y))));
	} else {
		tmp = x - (log1p((z * (y + (y * (z * (0.5 + (z * 0.16666666666666666))))))) / t);
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -50000000000000.0) {
		tmp = x * (1.0 + (1.0 / (t * (((x / (1.0 - Math.exp(z))) - (0.5 * (x * y))) / y))));
	} else {
		tmp = x - (Math.log1p((z * (y + (y * (z * (0.5 + (z * 0.16666666666666666))))))) / t);
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -50000000000000.0:
		tmp = x * (1.0 + (1.0 / (t * (((x / (1.0 - math.exp(z))) - (0.5 * (x * y))) / y))))
	else:
		tmp = x - (math.log1p((z * (y + (y * (z * (0.5 + (z * 0.16666666666666666))))))) / t)
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -50000000000000.0)
		tmp = Float64(x * Float64(1.0 + Float64(1.0 / Float64(t * Float64(Float64(Float64(x / Float64(1.0 - exp(z))) - Float64(0.5 * Float64(x * y))) / y)))));
	else
		tmp = Float64(x - Float64(log1p(Float64(z * Float64(y + Float64(y * Float64(z * Float64(0.5 + Float64(z * 0.16666666666666666))))))) / t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[z, -50000000000000.0], N[(x * N[(1.0 + N[(1.0 / N[(t * N[(N[(N[(x / N[(1.0 - N[Exp[z], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(0.5 * N[(x * y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[Log[1 + N[(z * N[(y + N[(y * N[(z * N[(0.5 + N[(z * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -50000000000000:\\
\;\;\;\;x \cdot \left(1 + \frac{1}{t \cdot \frac{\frac{x}{1 - e^{z}} - 0.5 \cdot \left(x \cdot y\right)}{y}}\right)\\

\mathbf{else}:\\
\;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + z \cdot 0.16666666666666666\right)\right)\right)\right)}{t}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -5e13

    1. Initial program 83.5%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-83.5%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg83.5%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      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 80.8%

      \[\leadsto \color{blue}{x \cdot \left(1 + -1 \cdot \frac{\log \left(1 + y \cdot \left(e^{z} - 1\right)\right)}{t \cdot x}\right)} \]
    6. Step-by-step derivation
      1. mul-1-neg80.8%

        \[\leadsto x \cdot \left(1 + \color{blue}{\left(-\frac{\log \left(1 + y \cdot \left(e^{z} - 1\right)\right)}{t \cdot x}\right)}\right) \]
      2. unsub-neg80.8%

        \[\leadsto x \cdot \color{blue}{\left(1 - \frac{\log \left(1 + y \cdot \left(e^{z} - 1\right)\right)}{t \cdot x}\right)} \]
      3. log1p-define90.7%

        \[\leadsto x \cdot \left(1 - \frac{\color{blue}{\mathsf{log1p}\left(y \cdot \left(e^{z} - 1\right)\right)}}{t \cdot x}\right) \]
      4. expm1-define90.7%

        \[\leadsto x \cdot \left(1 - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t \cdot x}\right) \]
    7. Simplified90.7%

      \[\leadsto \color{blue}{x \cdot \left(1 - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t \cdot x}\right)} \]
    8. Step-by-step derivation
      1. clear-num90.6%

        \[\leadsto x \cdot \left(1 - \color{blue}{\frac{1}{\frac{t \cdot x}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}}\right) \]
      2. inv-pow90.6%

        \[\leadsto x \cdot \left(1 - \color{blue}{{\left(\frac{t \cdot x}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}\right)}^{-1}}\right) \]
      3. *-un-lft-identity90.6%

        \[\leadsto x \cdot \left(1 - {\left(\frac{t \cdot x}{\color{blue}{1 \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}\right)}^{-1}\right) \]
      4. times-frac93.4%

        \[\leadsto x \cdot \left(1 - {\color{blue}{\left(\frac{t}{1} \cdot \frac{x}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}\right)}}^{-1}\right) \]
      5. /-rgt-identity93.4%

        \[\leadsto x \cdot \left(1 - {\left(\color{blue}{t} \cdot \frac{x}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}\right)}^{-1}\right) \]
    9. Applied egg-rr93.4%

      \[\leadsto x \cdot \left(1 - \color{blue}{{\left(t \cdot \frac{x}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}\right)}^{-1}}\right) \]
    10. Step-by-step derivation
      1. unpow-193.4%

        \[\leadsto x \cdot \left(1 - \color{blue}{\frac{1}{t \cdot \frac{x}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}}\right) \]
    11. Simplified93.4%

      \[\leadsto x \cdot \left(1 - \color{blue}{\frac{1}{t \cdot \frac{x}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}}\right) \]
    12. Taylor expanded in y around 0 84.1%

      \[\leadsto x \cdot \left(1 - \frac{1}{t \cdot \color{blue}{\frac{0.5 \cdot \left(x \cdot y\right) + \frac{x}{e^{z} - 1}}{y}}}\right) \]

    if -5e13 < z

    1. Initial program 53.3%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    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-define81.6%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub081.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub081.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      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 97.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{z \cdot \left(y + z \cdot \left(0.16666666666666666 \cdot \left(y \cdot z\right) + 0.5 \cdot y\right)\right)}\right)}{t} \]
    6. Taylor expanded in t around 0 85.5%

      \[\leadsto x - \color{blue}{\frac{\log \left(1 + z \cdot \left(y + z \cdot \left(0.16666666666666666 \cdot \left(y \cdot z\right) + 0.5 \cdot y\right)\right)\right)}{t}} \]
    7. Step-by-step derivation
      1. log1p-define97.8%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(z \cdot \left(y + z \cdot \left(0.16666666666666666 \cdot \left(y \cdot z\right) + 0.5 \cdot y\right)\right)\right)}}{t} \]
      2. distribute-rgt-in97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \color{blue}{\left(\left(0.16666666666666666 \cdot \left(y \cdot z\right)\right) \cdot z + \left(0.5 \cdot y\right) \cdot z\right)}\right)\right)}{t} \]
      3. *-commutative97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(\color{blue}{z \cdot \left(0.16666666666666666 \cdot \left(y \cdot z\right)\right)} + \left(0.5 \cdot y\right) \cdot z\right)\right)\right)}{t} \]
      4. associate-*r*97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(\color{blue}{\left(z \cdot 0.16666666666666666\right) \cdot \left(y \cdot z\right)} + \left(0.5 \cdot y\right) \cdot z\right)\right)\right)}{t} \]
      5. *-commutative97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(\color{blue}{\left(0.16666666666666666 \cdot z\right)} \cdot \left(y \cdot z\right) + \left(0.5 \cdot y\right) \cdot z\right)\right)\right)}{t} \]
      6. associate-*r*97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(\left(0.16666666666666666 \cdot z\right) \cdot \left(y \cdot z\right) + \color{blue}{0.5 \cdot \left(y \cdot z\right)}\right)\right)\right)}{t} \]
      7. distribute-rgt-in97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \color{blue}{\left(y \cdot z\right) \cdot \left(0.16666666666666666 \cdot z + 0.5\right)}\right)\right)}{t} \]
      8. +-commutative97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(y \cdot z\right) \cdot \color{blue}{\left(0.5 + 0.16666666666666666 \cdot z\right)}\right)\right)}{t} \]
      9. associate-*r*97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \color{blue}{y \cdot \left(z \cdot \left(0.5 + 0.16666666666666666 \cdot z\right)\right)}\right)\right)}{t} \]
      10. *-commutative97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + \color{blue}{z \cdot 0.16666666666666666}\right)\right)\right)\right)}{t} \]
    8. Simplified97.8%

      \[\leadsto x - \color{blue}{\frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + z \cdot 0.16666666666666666\right)\right)\right)\right)}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification93.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -50000000000000:\\ \;\;\;\;x \cdot \left(1 + \frac{1}{t \cdot \frac{\frac{x}{1 - e^{z}} - 0.5 \cdot \left(x \cdot y\right)}{y}}\right)\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + z \cdot 0.16666666666666666\right)\right)\right)\right)}{t}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 91.7% accurate, 1.7× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -50000000000000:\\ \;\;\;\;x - \mathsf{expm1}\left(z\right) \cdot \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + z \cdot 0.16666666666666666\right)\right)\right)\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -50000000000000.0)
   (- x (* (expm1 z) (/ y t)))
   (-
    x
    (/ (log1p (* z (+ y (* y (* z (+ 0.5 (* z 0.16666666666666666))))))) t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -50000000000000.0) {
		tmp = x - (expm1(z) * (y / t));
	} else {
		tmp = x - (log1p((z * (y + (y * (z * (0.5 + (z * 0.16666666666666666))))))) / t);
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -50000000000000.0) {
		tmp = x - (Math.expm1(z) * (y / t));
	} else {
		tmp = x - (Math.log1p((z * (y + (y * (z * (0.5 + (z * 0.16666666666666666))))))) / t);
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -50000000000000.0:
		tmp = x - (math.expm1(z) * (y / t))
	else:
		tmp = x - (math.log1p((z * (y + (y * (z * (0.5 + (z * 0.16666666666666666))))))) / t)
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -50000000000000.0)
		tmp = Float64(x - Float64(expm1(z) * Float64(y / t)));
	else
		tmp = Float64(x - Float64(log1p(Float64(z * Float64(y + Float64(y * Float64(z * Float64(0.5 + Float64(z * 0.16666666666666666))))))) / t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[z, -50000000000000.0], N[(x - N[(N[(Exp[z] - 1), $MachinePrecision] * N[(y / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[Log[1 + N[(z * N[(y + N[(y * N[(z * N[(0.5 + N[(z * 0.16666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -50000000000000:\\
\;\;\;\;x - \mathsf{expm1}\left(z\right) \cdot \frac{y}{t}\\

\mathbf{else}:\\
\;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + z \cdot 0.16666666666666666\right)\right)\right)\right)}{t}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -5e13

    1. Initial program 83.5%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-83.5%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg83.5%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      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 y around 0 83.0%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
    6. Step-by-step derivation
      1. associate-/l*83.0%

        \[\leadsto x - \color{blue}{y \cdot \frac{e^{z} - 1}{t}} \]
      2. expm1-define83.0%

        \[\leadsto x - y \cdot \frac{\color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
    7. Simplified83.0%

      \[\leadsto x - \color{blue}{y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}} \]
    8. Step-by-step derivation
      1. clear-num83.0%

        \[\leadsto x - y \cdot \color{blue}{\frac{1}{\frac{t}{\mathsf{expm1}\left(z\right)}}} \]
      2. un-div-inv83.0%

        \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{\mathsf{expm1}\left(z\right)}}} \]
    9. Applied egg-rr83.0%

      \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{\mathsf{expm1}\left(z\right)}}} \]
    10. Step-by-step derivation
      1. associate-/r/83.0%

        \[\leadsto x - \color{blue}{\frac{y}{t} \cdot \mathsf{expm1}\left(z\right)} \]
    11. Simplified83.0%

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

    if -5e13 < z

    1. Initial program 53.3%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    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-define81.6%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub081.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub081.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--81.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      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 97.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{z \cdot \left(y + z \cdot \left(0.16666666666666666 \cdot \left(y \cdot z\right) + 0.5 \cdot y\right)\right)}\right)}{t} \]
    6. Taylor expanded in t around 0 85.5%

      \[\leadsto x - \color{blue}{\frac{\log \left(1 + z \cdot \left(y + z \cdot \left(0.16666666666666666 \cdot \left(y \cdot z\right) + 0.5 \cdot y\right)\right)\right)}{t}} \]
    7. Step-by-step derivation
      1. log1p-define97.8%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(z \cdot \left(y + z \cdot \left(0.16666666666666666 \cdot \left(y \cdot z\right) + 0.5 \cdot y\right)\right)\right)}}{t} \]
      2. distribute-rgt-in97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \color{blue}{\left(\left(0.16666666666666666 \cdot \left(y \cdot z\right)\right) \cdot z + \left(0.5 \cdot y\right) \cdot z\right)}\right)\right)}{t} \]
      3. *-commutative97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(\color{blue}{z \cdot \left(0.16666666666666666 \cdot \left(y \cdot z\right)\right)} + \left(0.5 \cdot y\right) \cdot z\right)\right)\right)}{t} \]
      4. associate-*r*97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(\color{blue}{\left(z \cdot 0.16666666666666666\right) \cdot \left(y \cdot z\right)} + \left(0.5 \cdot y\right) \cdot z\right)\right)\right)}{t} \]
      5. *-commutative97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(\color{blue}{\left(0.16666666666666666 \cdot z\right)} \cdot \left(y \cdot z\right) + \left(0.5 \cdot y\right) \cdot z\right)\right)\right)}{t} \]
      6. associate-*r*97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(\left(0.16666666666666666 \cdot z\right) \cdot \left(y \cdot z\right) + \color{blue}{0.5 \cdot \left(y \cdot z\right)}\right)\right)\right)}{t} \]
      7. distribute-rgt-in97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \color{blue}{\left(y \cdot z\right) \cdot \left(0.16666666666666666 \cdot z + 0.5\right)}\right)\right)}{t} \]
      8. +-commutative97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \left(y \cdot z\right) \cdot \color{blue}{\left(0.5 + 0.16666666666666666 \cdot z\right)}\right)\right)}{t} \]
      9. associate-*r*97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + \color{blue}{y \cdot \left(z \cdot \left(0.5 + 0.16666666666666666 \cdot z\right)\right)}\right)\right)}{t} \]
      10. *-commutative97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + \color{blue}{z \cdot 0.16666666666666666}\right)\right)\right)\right)}{t} \]
    8. Simplified97.8%

      \[\leadsto x - \color{blue}{\frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + z \cdot 0.16666666666666666\right)\right)\right)\right)}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification93.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -50000000000000:\\ \;\;\;\;x - \mathsf{expm1}\left(z\right) \cdot \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + y \cdot \left(z \cdot \left(0.5 + z \cdot 0.16666666666666666\right)\right)\right)\right)}{t}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 91.6% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -4.3 \cdot 10^{-7}:\\ \;\;\;\;x - \mathsf{expm1}\left(z\right) \cdot \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + 0.5 \cdot \left(y \cdot z\right)\right)\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -4.3e-7)
   (- x (* (expm1 z) (/ y t)))
   (- x (/ (log1p (* z (+ y (* 0.5 (* y z))))) t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -4.3e-7) {
		tmp = x - (expm1(z) * (y / t));
	} else {
		tmp = x - (log1p((z * (y + (0.5 * (y * z))))) / t);
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -4.3e-7) {
		tmp = x - (Math.expm1(z) * (y / t));
	} else {
		tmp = x - (Math.log1p((z * (y + (0.5 * (y * z))))) / t);
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -4.3e-7:
		tmp = x - (math.expm1(z) * (y / t))
	else:
		tmp = x - (math.log1p((z * (y + (0.5 * (y * z))))) / t)
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -4.3e-7)
		tmp = Float64(x - Float64(expm1(z) * Float64(y / t)));
	else
		tmp = Float64(x - Float64(log1p(Float64(z * Float64(y + Float64(0.5 * Float64(y * z))))) / t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[z, -4.3e-7], N[(x - N[(N[(Exp[z] - 1), $MachinePrecision] * N[(y / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[Log[1 + N[(z * N[(y + N[(0.5 * N[(y * z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -4.3 \cdot 10^{-7}:\\
\;\;\;\;x - \mathsf{expm1}\left(z\right) \cdot \frac{y}{t}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -4.3000000000000001e-7

    1. Initial program 83.4%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-83.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg83.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      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--99.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define99.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.9%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in y around 0 82.5%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
    6. Step-by-step derivation
      1. associate-/l*82.5%

        \[\leadsto x - \color{blue}{y \cdot \frac{e^{z} - 1}{t}} \]
      2. expm1-define82.9%

        \[\leadsto x - y \cdot \frac{\color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
    7. Simplified82.9%

      \[\leadsto x - \color{blue}{y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}} \]
    8. Step-by-step derivation
      1. clear-num82.9%

        \[\leadsto x - y \cdot \color{blue}{\frac{1}{\frac{t}{\mathsf{expm1}\left(z\right)}}} \]
      2. un-div-inv82.9%

        \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{\mathsf{expm1}\left(z\right)}}} \]
    9. Applied egg-rr82.9%

      \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{\mathsf{expm1}\left(z\right)}}} \]
    10. Step-by-step derivation
      1. associate-/r/82.9%

        \[\leadsto x - \color{blue}{\frac{y}{t} \cdot \mathsf{expm1}\left(z\right)} \]
    11. Simplified82.9%

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

    if -4.3000000000000001e-7 < z

    1. Initial program 52.5%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    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-define81.2%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub081.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-81.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub081.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative81.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg81.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity81.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--81.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      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 98.2%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{z \cdot \left(y + 0.5 \cdot \left(y \cdot z\right)\right)}\right)}{t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification93.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -4.3 \cdot 10^{-7}:\\ \;\;\;\;x - \mathsf{expm1}\left(z\right) \cdot \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(z \cdot \left(y + 0.5 \cdot \left(y \cdot z\right)\right)\right)}{t}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 86.6% accurate, 2.0× speedup?

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

\\
x - y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}
\end{array}
Derivation
  1. Initial program 61.9%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. associate-+l-81.9%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
    2. sub-neg81.9%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
    3. log1p-define86.8%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
    4. neg-sub086.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
    5. associate-+l-86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
    6. neg-sub086.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
    7. +-commutative86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    8. unsub-neg86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
    9. *-rgt-identity86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    10. distribute-lft-out--86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    11. expm1-define98.7%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified98.7%

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

      \[\leadsto x - \color{blue}{y \cdot \frac{e^{z} - 1}{t}} \]
    2. expm1-define90.4%

      \[\leadsto x - y \cdot \frac{\color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
  7. Simplified90.4%

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

Alternative 6: 82.3% accurate, 10.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -0.62:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \left(z \cdot \left(0.5 \cdot \frac{z}{t} + \frac{1}{t}\right)\right)\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -0.62) 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 <= -0.62) {
		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 <= (-0.62d0)) 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 <= -0.62) {
		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 <= -0.62:
		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 <= -0.62)
		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 <= -0.62)
		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, -0.62], 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 -0.62:\\
\;\;\;\;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 < -0.619999999999999996

    1. Initial program 84.2%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-84.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg84.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      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 70.5%

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

    if -0.619999999999999996 < z

    1. Initial program 52.5%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-80.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg80.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define81.2%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub081.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-81.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub081.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative81.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg81.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity81.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--81.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      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 y around 0 81.3%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
    6. Step-by-step derivation
      1. associate-/l*81.3%

        \[\leadsto x - \color{blue}{y \cdot \frac{e^{z} - 1}{t}} \]
      2. expm1-define93.8%

        \[\leadsto x - y \cdot \frac{\color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
    7. Simplified93.8%

      \[\leadsto x - \color{blue}{y \cdot \frac{\mathsf{expm1}\left(z\right)}{t}} \]
    8. Taylor expanded in z around 0 93.7%

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

Alternative 7: 72.3% accurate, 13.2× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;t \leq -2.25 \cdot 10^{-246}:\\ \;\;\;\;x\\ \mathbf{elif}\;t \leq 9.5 \cdot 10^{-248}:\\ \;\;\;\;y \cdot \frac{z}{-t}\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= t -2.25e-246) x (if (<= t 9.5e-248) (* y (/ z (- t))) x)))
double code(double x, double y, double z, double t) {
	double tmp;
	if (t <= -2.25e-246) {
		tmp = x;
	} else if (t <= 9.5e-248) {
		tmp = y * (z / -t);
	} 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 <= (-2.25d-246)) then
        tmp = x
    else if (t <= 9.5d-248) then
        tmp = y * (z / -t)
    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 <= -2.25e-246) {
		tmp = x;
	} else if (t <= 9.5e-248) {
		tmp = y * (z / -t);
	} else {
		tmp = x;
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if t <= -2.25e-246:
		tmp = x
	elif t <= 9.5e-248:
		tmp = y * (z / -t)
	else:
		tmp = x
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (t <= -2.25e-246)
		tmp = x;
	elseif (t <= 9.5e-248)
		tmp = Float64(y * Float64(z / Float64(-t)));
	else
		tmp = x;
	end
	return tmp
end
function tmp_2 = code(x, y, z, t)
	tmp = 0.0;
	if (t <= -2.25e-246)
		tmp = x;
	elseif (t <= 9.5e-248)
		tmp = y * (z / -t);
	else
		tmp = x;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[t, -2.25e-246], x, If[LessEqual[t, 9.5e-248], N[(y * N[(z / (-t)), $MachinePrecision]), $MachinePrecision], x]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;t \leq -2.25 \cdot 10^{-246}:\\
\;\;\;\;x\\

\mathbf{elif}\;t \leq 9.5 \cdot 10^{-248}:\\
\;\;\;\;y \cdot \frac{z}{-t}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if t < -2.25e-246 or 9.49999999999999971e-248 < t

    1. Initial program 65.7%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-86.7%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg86.7%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define91.3%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub091.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-91.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub091.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative91.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg91.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity91.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--91.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      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 x around inf 82.9%

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

    if -2.25e-246 < t < 9.49999999999999971e-248

    1. Initial program 21.1%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-30.0%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg30.0%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      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--39.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      11. expm1-define91.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified91.4%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Add Preprocessing
    5. Taylor expanded in z around 0 70.3%

      \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
    6. Step-by-step derivation
      1. associate-/l*78.6%

        \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
    7. Simplified78.6%

      \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
    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. associate-/l*57.9%

        \[\leadsto -1 \cdot \color{blue}{\left(y \cdot \frac{z}{t}\right)} \]
      2. associate-*r*57.9%

        \[\leadsto \color{blue}{\left(-1 \cdot y\right) \cdot \frac{z}{t}} \]
      3. neg-mul-157.9%

        \[\leadsto \color{blue}{\left(-y\right)} \cdot \frac{z}{t} \]
      4. *-commutative57.9%

        \[\leadsto \color{blue}{\frac{z}{t} \cdot \left(-y\right)} \]
    10. Simplified57.9%

      \[\leadsto \color{blue}{\frac{z}{t} \cdot \left(-y\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \leq -2.25 \cdot 10^{-246}:\\ \;\;\;\;x\\ \mathbf{elif}\;t \leq 9.5 \cdot 10^{-248}:\\ \;\;\;\;y \cdot \frac{z}{-t}\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 82.1% accurate, 17.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -4.2 \cdot 10^{+25}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{z}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -4.2e+25) x (- x (* y (/ z t)))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -4.2e+25) {
		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 <= (-4.2d+25)) 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 <= -4.2e+25) {
		tmp = x;
	} else {
		tmp = x - (y * (z / t));
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -4.2e+25:
		tmp = x
	else:
		tmp = x - (y * (z / t))
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -4.2e+25)
		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 <= -4.2e+25)
		tmp = x;
	else
		tmp = x - (y * (z / t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[z, -4.2e+25], x, N[(x - N[(y * N[(z / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -4.2 \cdot 10^{+25}:\\
\;\;\;\;x\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -4.1999999999999998e25

    1. Initial program 84.2%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-84.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg84.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      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 72.1%

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

    if -4.1999999999999998e25 < z

    1. Initial program 53.5%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. associate-+l-81.0%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
      2. sub-neg81.0%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
      3. log1p-define81.9%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
      4. neg-sub081.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
      5. associate-+l-81.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
      6. neg-sub081.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
      7. +-commutative81.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      8. unsub-neg81.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      9. *-rgt-identity81.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      10. distribute-lft-out--81.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      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 91.0%

      \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
    6. Step-by-step derivation
      1. associate-/l*92.2%

        \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
    7. Simplified92.2%

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

Alternative 9: 71.2% 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 61.9%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. associate-+l-81.9%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 - \left(y - y \cdot e^{z}\right)\right)}}{t} \]
    2. sub-neg81.9%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(-\left(y - y \cdot e^{z}\right)\right)\right)}}{t} \]
    3. log1p-define86.8%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(-\left(y - y \cdot e^{z}\right)\right)}}{t} \]
    4. neg-sub086.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0 - \left(y - y \cdot e^{z}\right)}\right)}{t} \]
    5. associate-+l-86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0 - y\right) + y \cdot e^{z}}\right)}{t} \]
    6. neg-sub086.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right)} + y \cdot e^{z}\right)}{t} \]
    7. +-commutative86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    8. unsub-neg86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
    9. *-rgt-identity86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    10. distribute-lft-out--86.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    11. expm1-define98.7%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified98.7%

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

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

Developer target: 74.0% 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 2024091 
(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)))