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

Percentage Accurate: 61.4% → 98.5%
Time: 17.5s
Alternatives: 7
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 7 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 57.8%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. sub-neg57.8%

      \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
    2. associate-+l+73.4%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
    3. cancel-sign-sub73.4%

      \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
    4. log1p-def80.1%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
    5. cancel-sign-sub80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
    6. +-commutative80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    7. neg-mul-180.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
    8. metadata-eval80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
    9. cancel-sign-sub-inv80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
    10. *-commutative80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    11. distribute-lft-out--80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    12. expm1-def97.3%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified97.3%

    \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
  4. Final simplification97.3%

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

Alternative 2: 88.1% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -1.25 \cdot 10^{-31}:\\ \;\;\;\;x + \frac{-1}{t \cdot 0.5 + \frac{t}{y \cdot \left(e^{z} + -1\right)}}\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{z}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -1.25e-31)
   (+ x (/ -1.0 (+ (* t 0.5) (/ t (* y (+ (exp z) -1.0))))))
   (- x (* y (/ z t)))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -1.25e-31) {
		tmp = x + (-1.0 / ((t * 0.5) + (t / (y * (exp(z) + -1.0)))));
	} 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 <= (-1.25d-31)) then
        tmp = x + ((-1.0d0) / ((t * 0.5d0) + (t / (y * (exp(z) + (-1.0d0))))))
    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 <= -1.25e-31) {
		tmp = x + (-1.0 / ((t * 0.5) + (t / (y * (Math.exp(z) + -1.0)))));
	} else {
		tmp = x - (y * (z / t));
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -1.25e-31:
		tmp = x + (-1.0 / ((t * 0.5) + (t / (y * (math.exp(z) + -1.0)))))
	else:
		tmp = x - (y * (z / t))
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -1.25e-31)
		tmp = Float64(x + Float64(-1.0 / Float64(Float64(t * 0.5) + Float64(t / Float64(y * Float64(exp(z) + -1.0))))));
	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 <= -1.25e-31)
		tmp = x + (-1.0 / ((t * 0.5) + (t / (y * (exp(z) + -1.0)))));
	else
		tmp = x - (y * (z / t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[z, -1.25e-31], N[(x + N[(-1.0 / N[(N[(t * 0.5), $MachinePrecision] + N[(t / N[(y * N[(N[Exp[z], $MachinePrecision] + -1.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x - N[(y * N[(z / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -1.25 \cdot 10^{-31}:\\
\;\;\;\;x + \frac{-1}{t \cdot 0.5 + \frac{t}{y \cdot \left(e^{z} + -1\right)}}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -1.25e-31

    1. Initial program 79.0%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg79.0%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+80.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub80.2%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def98.1%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub98.1%

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

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-198.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval98.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv98.1%

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

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--98.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def100.0%

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

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Step-by-step derivation
      1. div-inv99.8%

        \[\leadsto x - \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right) \cdot \frac{1}{t}} \]
      2. *-commutative99.8%

        \[\leadsto x - \color{blue}{\frac{1}{t} \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)} \]
    5. Applied egg-rr99.8%

      \[\leadsto x - \color{blue}{\frac{1}{t} \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)} \]
    6. Step-by-step derivation
      1. associate-/r/99.8%

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}} \]
    7. Applied egg-rr99.8%

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}} \]
    8. Taylor expanded in y around 0 83.2%

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

    if -1.25e-31 < z

    1. Initial program 47.7%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg47.7%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+70.2%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub70.2%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def71.4%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub71.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative71.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-171.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval71.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv71.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
      10. *-commutative71.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--71.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def96.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified96.0%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Step-by-step derivation
      1. div-inv96.1%

        \[\leadsto x - \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right) \cdot \frac{1}{t}} \]
      2. *-commutative96.1%

        \[\leadsto x - \color{blue}{\frac{1}{t} \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)} \]
    5. Applied egg-rr96.1%

      \[\leadsto x - \color{blue}{\frac{1}{t} \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)} \]
    6. Step-by-step derivation
      1. associate-/r/96.0%

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}} \]
    7. Applied egg-rr96.0%

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}} \]
    8. Taylor expanded in z around 0 86.1%

      \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
    9. Step-by-step derivation
      1. associate-*r/88.7%

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

      \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification86.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -1.25 \cdot 10^{-31}:\\ \;\;\;\;x + \frac{-1}{t \cdot 0.5 + \frac{t}{y \cdot \left(e^{z} + -1\right)}}\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{z}{t}\\ \end{array} \]

Alternative 3: 84.9% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -9.5 \cdot 10^{+171}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - \mathsf{expm1}\left(z\right) \cdot \frac{y}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= y -9.5e+171) x (- x (* (expm1 z) (/ y t)))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (y <= -9.5e+171) {
		tmp = x;
	} else {
		tmp = x - (expm1(z) * (y / t));
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (y <= -9.5e+171) {
		tmp = x;
	} else {
		tmp = x - (Math.expm1(z) * (y / t));
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if y <= -9.5e+171:
		tmp = x
	else:
		tmp = x - (math.expm1(z) * (y / t))
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (y <= -9.5e+171)
		tmp = x;
	else
		tmp = Float64(x - Float64(expm1(z) * Float64(y / t)));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[y, -9.5e+171], x, N[(x - N[(N[(Exp[z] - 1), $MachinePrecision] * N[(y / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -9.5 \cdot 10^{+171}:\\
\;\;\;\;x\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -9.49999999999999924e171

    1. Initial program 46.2%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg46.2%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+66.6%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub66.6%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def66.6%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub66.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative66.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-166.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval66.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv66.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
      10. *-commutative66.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--66.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def99.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.7%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in x around inf 44.7%

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

    if -9.49999999999999924e171 < y

    1. Initial program 59.3%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg59.3%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+74.3%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub74.3%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def81.8%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub81.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative81.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-181.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval81.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv81.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
      10. *-commutative81.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--81.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def97.0%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified97.0%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in y around 0 77.8%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
    5. Step-by-step derivation
      1. associate-/l*77.8%

        \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{e^{z} - 1}}} \]
      2. associate-/r/77.6%

        \[\leadsto x - \color{blue}{\frac{y}{t} \cdot \left(e^{z} - 1\right)} \]
      3. expm1-def89.7%

        \[\leadsto x - \frac{y}{t} \cdot \color{blue}{\mathsf{expm1}\left(z\right)} \]
    6. Simplified89.7%

      \[\leadsto x - \color{blue}{\frac{y}{t} \cdot \mathsf{expm1}\left(z\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification84.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -9.5 \cdot 10^{+171}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - \mathsf{expm1}\left(z\right) \cdot \frac{y}{t}\\ \end{array} \]

Alternative 4: 86.0% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;y \leq -2.1 \cdot 10^{+211}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= y -2.1e+211) x (- x (/ (* y (expm1 z)) t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (y <= -2.1e+211) {
		tmp = x;
	} 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 <= -2.1e+211) {
		tmp = x;
	} else {
		tmp = x - ((y * Math.expm1(z)) / t);
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if y <= -2.1e+211:
		tmp = x
	else:
		tmp = x - ((y * math.expm1(z)) / t)
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (y <= -2.1e+211)
		tmp = x;
	else
		tmp = Float64(x - Float64(Float64(y * expm1(z)) / t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[y, -2.1e+211], x, N[(x - N[(N[(y * N[(Exp[z] - 1), $MachinePrecision]), $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;y \leq -2.1 \cdot 10^{+211}:\\
\;\;\;\;x\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if y < -2.1e211

    1. Initial program 42.6%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg42.6%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+60.1%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub60.1%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def60.1%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub60.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative60.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-160.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval60.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv60.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
      10. *-commutative60.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--60.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def99.5%

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

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in x around inf 42.9%

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

    if -2.1e211 < y

    1. Initial program 58.9%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg58.9%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+74.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub74.4%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def81.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub81.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative81.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-181.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval81.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv81.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
      10. *-commutative81.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--81.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def97.1%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified97.1%

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

      \[\leadsto x - \frac{\color{blue}{y \cdot \left(e^{z} - 1\right)}}{t} \]
    5. Step-by-step derivation
      1. expm1-def88.2%

        \[\leadsto x - \frac{y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}}{t} \]
    6. Simplified88.2%

      \[\leadsto x - \frac{\color{blue}{y \cdot \mathsf{expm1}\left(z\right)}}{t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification85.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;y \leq -2.1 \cdot 10^{+211}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - \frac{y \cdot \mathsf{expm1}\left(z\right)}{t}\\ \end{array} \]

Alternative 5: 70.7% accurate, 20.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -6.2 \cdot 10^{-227}:\\ \;\;\;\;x\\ \mathbf{elif}\;x \leq 5.9 \cdot 10^{-263}:\\ \;\;\;\;y \cdot \frac{-z}{t}\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= x -6.2e-227) x (if (<= x 5.9e-263) (* y (/ (- z) t)) x)))
double code(double x, double y, double z, double t) {
	double tmp;
	if (x <= -6.2e-227) {
		tmp = x;
	} else if (x <= 5.9e-263) {
		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 (x <= (-6.2d-227)) then
        tmp = x
    else if (x <= 5.9d-263) 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 (x <= -6.2e-227) {
		tmp = x;
	} else if (x <= 5.9e-263) {
		tmp = y * (-z / t);
	} else {
		tmp = x;
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if x <= -6.2e-227:
		tmp = x
	elif x <= 5.9e-263:
		tmp = y * (-z / t)
	else:
		tmp = x
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (x <= -6.2e-227)
		tmp = x;
	elseif (x <= 5.9e-263)
		tmp = Float64(y * Float64(Float64(-z) / t));
	else
		tmp = x;
	end
	return tmp
end
function tmp_2 = code(x, y, z, t)
	tmp = 0.0;
	if (x <= -6.2e-227)
		tmp = x;
	elseif (x <= 5.9e-263)
		tmp = y * (-z / t);
	else
		tmp = x;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[x, -6.2e-227], x, If[LessEqual[x, 5.9e-263], N[(y * N[((-z) / t), $MachinePrecision]), $MachinePrecision], x]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -6.2 \cdot 10^{-227}:\\
\;\;\;\;x\\

\mathbf{elif}\;x \leq 5.9 \cdot 10^{-263}:\\
\;\;\;\;y \cdot \frac{-z}{t}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -6.19999999999999959e-227 or 5.89999999999999972e-263 < x

    1. Initial program 61.4%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg61.4%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+78.3%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub78.3%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def84.4%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub84.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative84.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-184.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval84.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv84.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
      10. *-commutative84.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--84.4%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def97.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified97.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in x around inf 72.7%

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

    if -6.19999999999999959e-227 < x < 5.89999999999999972e-263

    1. Initial program 20.5%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg20.5%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+21.6%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub21.6%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def34.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub34.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative34.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-134.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval34.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv34.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
      10. *-commutative34.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--34.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def92.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified92.2%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in z around 0 49.9%

      \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
    5. Step-by-step derivation
      1. associate-/l*53.0%

        \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{z}}} \]
      2. associate-/r/52.8%

        \[\leadsto x - \color{blue}{\frac{y}{t} \cdot z} \]
    6. Simplified52.8%

      \[\leadsto x - \color{blue}{\frac{y}{t} \cdot z} \]
    7. Taylor expanded in x around 0 41.6%

      \[\leadsto \color{blue}{-1 \cdot \frac{y \cdot z}{t}} \]
    8. Step-by-step derivation
      1. associate-*r/41.6%

        \[\leadsto \color{blue}{\frac{-1 \cdot \left(y \cdot z\right)}{t}} \]
      2. neg-mul-141.6%

        \[\leadsto \frac{\color{blue}{-y \cdot z}}{t} \]
      3. distribute-lft-neg-in41.6%

        \[\leadsto \frac{\color{blue}{\left(-y\right) \cdot z}}{t} \]
      4. associate-*l/44.5%

        \[\leadsto \color{blue}{\frac{-y}{t} \cdot z} \]
    9. Simplified44.5%

      \[\leadsto \color{blue}{\frac{-y}{t} \cdot z} \]
    10. Taylor expanded in y around 0 41.6%

      \[\leadsto \color{blue}{-1 \cdot \frac{y \cdot z}{t}} \]
    11. Step-by-step derivation
      1. mul-1-neg41.6%

        \[\leadsto \color{blue}{-\frac{y \cdot z}{t}} \]
      2. associate-*r/48.5%

        \[\leadsto -\color{blue}{y \cdot \frac{z}{t}} \]
      3. distribute-rgt-neg-out48.5%

        \[\leadsto \color{blue}{y \cdot \left(-\frac{z}{t}\right)} \]
      4. distribute-neg-frac48.5%

        \[\leadsto y \cdot \color{blue}{\frac{-z}{t}} \]
    12. Simplified48.5%

      \[\leadsto \color{blue}{y \cdot \frac{-z}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification70.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -6.2 \cdot 10^{-227}:\\ \;\;\;\;x\\ \mathbf{elif}\;x \leq 5.9 \cdot 10^{-263}:\\ \;\;\;\;y \cdot \frac{-z}{t}\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]

Alternative 6: 82.0% accurate, 23.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -6.2 \cdot 10^{+59}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{z}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -6.2e+59) x (- x (* y (/ z t)))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -6.2e+59) {
		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 <= (-6.2d+59)) 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 <= -6.2e+59) {
		tmp = x;
	} else {
		tmp = x - (y * (z / t));
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -6.2e+59:
		tmp = x
	else:
		tmp = x - (y * (z / t))
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -6.2e+59)
		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 <= -6.2e+59)
		tmp = x;
	else
		tmp = x - (y * (z / t));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[z, -6.2e+59], x, N[(x - N[(y * N[(z / t), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -6.2 \cdot 10^{+59}:\\
\;\;\;\;x\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -6.20000000000000029e59

    1. Initial program 84.4%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg84.4%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+84.4%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub84.4%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def99.9%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub99.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative99.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-199.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval99.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv99.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
      10. *-commutative99.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--99.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def99.9%

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

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in x around inf 64.8%

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

    if -6.20000000000000029e59 < z

    1. Initial program 49.4%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg49.4%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+70.0%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub70.0%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def73.7%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub73.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative73.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. neg-mul-173.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
      8. metadata-eval73.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
      9. cancel-sign-sub-inv73.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
      10. *-commutative73.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      11. distribute-lft-out--73.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      12. expm1-def96.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified96.5%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Step-by-step derivation
      1. div-inv96.5%

        \[\leadsto x - \color{blue}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right) \cdot \frac{1}{t}} \]
      2. *-commutative96.5%

        \[\leadsto x - \color{blue}{\frac{1}{t} \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)} \]
    5. Applied egg-rr96.5%

      \[\leadsto x - \color{blue}{\frac{1}{t} \cdot \mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)} \]
    6. Step-by-step derivation
      1. associate-/r/96.4%

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}} \]
    7. Applied egg-rr96.4%

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}} \]
    8. Taylor expanded in z around 0 83.2%

      \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
    9. Step-by-step derivation
      1. associate-*r/85.5%

        \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
    10. Simplified85.5%

      \[\leadsto x - \color{blue}{y \cdot \frac{z}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification80.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -6.2 \cdot 10^{+59}:\\ \;\;\;\;x\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{z}{t}\\ \end{array} \]

Alternative 7: 71.5% 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 57.8%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. sub-neg57.8%

      \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
    2. associate-+l+73.4%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
    3. cancel-sign-sub73.4%

      \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
    4. log1p-def80.1%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
    5. cancel-sign-sub80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
    6. +-commutative80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    7. neg-mul-180.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{-1 \cdot y}\right)}{t} \]
    8. metadata-eval80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} + \color{blue}{\left(-1\right)} \cdot y\right)}{t} \]
    9. cancel-sign-sub-inv80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - 1 \cdot y}\right)}{t} \]
    10. *-commutative80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    11. distribute-lft-out--80.1%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    12. expm1-def97.3%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified97.3%

    \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
  4. Taylor expanded in x around inf 67.6%

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

    \[\leadsto x \]

Developer target: 75.0% 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 2023301 
(FPCore (x y z t)
  :name "System.Random.MWC.Distributions:truncatedExp from mwc-random-0.13.3.2"
  :precision binary64

  :herbie-target
  (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)))