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

Percentage Accurate: 60.5% → 98.3%
Time: 20.0s
Alternatives: 11
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 11 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: 60.5% 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: 98.3% 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 63.7%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. sub-neg63.7%

      \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
    2. associate-+l+79.1%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
    3. cancel-sign-sub79.1%

      \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
    4. log1p-def83.8%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
    5. cancel-sign-sub83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
    6. +-commutative83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    7. unsub-neg83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
    8. *-rgt-identity83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    9. distribute-lft-out--83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    10. expm1-def97.7%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified97.7%

    \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
  4. Final simplification97.7%

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

Alternative 2: 93.4% accurate, 1.0× speedup?

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

\\
\begin{array}{l}
\mathbf{if}\;e^{z} \leq 0:\\
\;\;\;\;x + \frac{-1}{t \cdot 0.5 + \frac{t}{y \cdot \left(e^{z} + -1\right)}}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (exp.f64 z) < 0.0

    1. Initial program 84.1%

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

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+84.1%

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

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def99.8%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative99.8%

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

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Step-by-step derivation
      1. clear-num99.7%

        \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}} \]
      2. inv-pow99.7%

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

      \[\leadsto x - \color{blue}{{\left(\frac{t}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}\right)}^{-1}} \]
    6. Step-by-step derivation
      1. unpow-199.7%

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

      \[\leadsto x - \color{blue}{\frac{1}{\frac{t}{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}}} \]
    8. Taylor expanded in y around 0 83.0%

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

    if 0.0 < (exp.f64 z)

    1. Initial program 55.7%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg55.7%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+77.1%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub77.1%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def77.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def96.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified96.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in z around 0 97.5%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z}\right)}{t} \]
    5. Step-by-step derivation
      1. +-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z + 0.5 \cdot \left(y \cdot {z}^{2}\right)}\right)}{t} \]
      2. fma-def97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, z, 0.5 \cdot \left(y \cdot {z}^{2}\right)\right)}\right)}{t} \]
      3. *-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, \color{blue}{\left(y \cdot {z}^{2}\right) \cdot 0.5}\right)\right)}{t} \]
      4. associate-*l*97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, \color{blue}{y \cdot \left({z}^{2} \cdot 0.5\right)}\right)\right)}{t} \]
      5. *-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, y \cdot \color{blue}{\left(0.5 \cdot {z}^{2}\right)}\right)\right)}{t} \]
      6. unpow297.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, y \cdot \left(0.5 \cdot \color{blue}{\left(z \cdot z\right)}\right)\right)\right)}{t} \]
    6. Simplified97.5%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, z, y \cdot \left(0.5 \cdot \left(z \cdot z\right)\right)\right)}\right)}{t} \]
    7. Taylor expanded in t around 0 85.6%

      \[\leadsto x - \color{blue}{\frac{\log \left(1 + \left(0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z\right)\right)}{t}} \]
    8. Step-by-step derivation
      1. log1p-def97.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z\right)}}{t} \]
      2. associate-*r*97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0.5 \cdot y\right) \cdot {z}^{2}} + y \cdot z\right)}{t} \]
      3. *-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(y \cdot 0.5\right)} \cdot {z}^{2} + y \cdot z\right)}{t} \]
      4. associate-*r*97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(0.5 \cdot {z}^{2}\right)} + y \cdot z\right)}{t} \]
      5. distribute-lft-in97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(0.5 \cdot {z}^{2} + z\right)}\right)}{t} \]
      6. +-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\left(z + 0.5 \cdot {z}^{2}\right)}\right)}{t} \]
      7. unpow297.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \left(z + 0.5 \cdot \color{blue}{\left(z \cdot z\right)}\right)\right)}{t} \]
    9. Simplified97.5%

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

    \[\leadsto \begin{array}{l} \mathbf{if}\;e^{z} \leq 0:\\ \;\;\;\;x + \frac{-1}{t \cdot 0.5 + \frac{t}{y \cdot \left(e^{z} + -1\right)}}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot \left(z + 0.5 \cdot \left(z \cdot z\right)\right)\right)}{t}\\ \end{array} \]

Alternative 3: 91.2% accurate, 1.0× speedup?

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

\\
\begin{array}{l}
\mathbf{if}\;e^{z} \leq 0:\\
\;\;\;\;x + \frac{y}{t}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (exp.f64 z) < 0.0

    1. Initial program 84.1%

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

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+84.1%

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

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def99.8%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative99.8%

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

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in y around 0 76.6%

      \[\leadsto \color{blue}{x + y \cdot \left(\frac{1}{t} - \frac{e^{z}}{t}\right)} \]
    5. Taylor expanded in z around 0 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\left(\frac{1}{t} + \frac{z}{t}\right)}\right) \]
    6. Taylor expanded in z around inf 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\frac{z}{t}}\right) \]
    7. Taylor expanded in z around 0 76.7%

      \[\leadsto x + \color{blue}{\frac{y}{t}} \]

    if 0.0 < (exp.f64 z)

    1. Initial program 55.7%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg55.7%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+77.1%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub77.1%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def77.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def96.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified96.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in z around 0 97.5%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z}\right)}{t} \]
    5. Step-by-step derivation
      1. +-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z + 0.5 \cdot \left(y \cdot {z}^{2}\right)}\right)}{t} \]
      2. fma-def97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, z, 0.5 \cdot \left(y \cdot {z}^{2}\right)\right)}\right)}{t} \]
      3. *-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, \color{blue}{\left(y \cdot {z}^{2}\right) \cdot 0.5}\right)\right)}{t} \]
      4. associate-*l*97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, \color{blue}{y \cdot \left({z}^{2} \cdot 0.5\right)}\right)\right)}{t} \]
      5. *-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, y \cdot \color{blue}{\left(0.5 \cdot {z}^{2}\right)}\right)\right)}{t} \]
      6. unpow297.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, y \cdot \left(0.5 \cdot \color{blue}{\left(z \cdot z\right)}\right)\right)\right)}{t} \]
    6. Simplified97.5%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, z, y \cdot \left(0.5 \cdot \left(z \cdot z\right)\right)\right)}\right)}{t} \]
    7. Taylor expanded in t around 0 85.6%

      \[\leadsto x - \color{blue}{\frac{\log \left(1 + \left(0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z\right)\right)}{t}} \]
    8. Step-by-step derivation
      1. log1p-def97.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z\right)}}{t} \]
      2. associate-*r*97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0.5 \cdot y\right) \cdot {z}^{2}} + y \cdot z\right)}{t} \]
      3. *-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(y \cdot 0.5\right)} \cdot {z}^{2} + y \cdot z\right)}{t} \]
      4. associate-*r*97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(0.5 \cdot {z}^{2}\right)} + y \cdot z\right)}{t} \]
      5. distribute-lft-in97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(0.5 \cdot {z}^{2} + z\right)}\right)}{t} \]
      6. +-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\left(z + 0.5 \cdot {z}^{2}\right)}\right)}{t} \]
      7. unpow297.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \left(z + 0.5 \cdot \color{blue}{\left(z \cdot z\right)}\right)\right)}{t} \]
    9. Simplified97.5%

      \[\leadsto x - \color{blue}{\frac{\mathsf{log1p}\left(y \cdot \left(z + 0.5 \cdot \left(z \cdot z\right)\right)\right)}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification91.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;e^{z} \leq 0:\\ \;\;\;\;x + \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot \left(z + 0.5 \cdot \left(z \cdot z\right)\right)\right)}{t}\\ \end{array} \]

Alternative 4: 86.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;e^{z} \leq 1:\\ \;\;\;\;x - \frac{y}{\frac{t}{\mathsf{expm1}\left(z\right)}}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= (exp z) 1.0) (- x (/ y (/ t (expm1 z)))) (- x (/ (log1p (* y z)) t))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (exp(z) <= 1.0) {
		tmp = x - (y / (t / expm1(z)));
	} else {
		tmp = x - (log1p((y * z)) / t);
	}
	return tmp;
}
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (Math.exp(z) <= 1.0) {
		tmp = x - (y / (t / Math.expm1(z)));
	} else {
		tmp = x - (Math.log1p((y * z)) / t);
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if math.exp(z) <= 1.0:
		tmp = x - (y / (t / math.expm1(z)))
	else:
		tmp = x - (math.log1p((y * z)) / t)
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (exp(z) <= 1.0)
		tmp = Float64(x - Float64(y / Float64(t / expm1(z))));
	else
		tmp = Float64(x - Float64(log1p(Float64(y * z)) / t));
	end
	return tmp
end
code[x_, y_, z_, t_] := If[LessEqual[N[Exp[z], $MachinePrecision], 1.0], N[(x - N[(y / N[(t / N[(Exp[z] - 1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(x - N[(N[Log[1 + N[(y * z), $MachinePrecision]], $MachinePrecision] / t), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;e^{z} \leq 1:\\
\;\;\;\;x - \frac{y}{\frac{t}{\mathsf{expm1}\left(z\right)}}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (exp.f64 z) < 1

    1. Initial program 63.6%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg63.6%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+79.7%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub79.7%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def84.7%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub84.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative84.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg84.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity84.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--84.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def98.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified98.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in y around 0 77.9%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
    5. Step-by-step derivation
      1. associate-/l*77.9%

        \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{e^{z} - 1}}} \]
      2. expm1-def87.0%

        \[\leadsto x - \frac{y}{\frac{t}{\color{blue}{\mathsf{expm1}\left(z\right)}}} \]
    6. Simplified87.0%

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

    if 1 < (exp.f64 z)

    1. Initial program 64.6%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg64.6%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+64.6%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub64.6%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def64.6%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub64.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative64.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg64.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity64.6%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--64.7%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def73.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified73.2%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in z around 0 85.2%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z}\right)}{t} \]
    5. Step-by-step derivation
      1. +-commutative85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z + 0.5 \cdot \left(y \cdot {z}^{2}\right)}\right)}{t} \]
      2. fma-def85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, z, 0.5 \cdot \left(y \cdot {z}^{2}\right)\right)}\right)}{t} \]
      3. *-commutative85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, \color{blue}{\left(y \cdot {z}^{2}\right) \cdot 0.5}\right)\right)}{t} \]
      4. associate-*l*85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, \color{blue}{y \cdot \left({z}^{2} \cdot 0.5\right)}\right)\right)}{t} \]
      5. *-commutative85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, y \cdot \color{blue}{\left(0.5 \cdot {z}^{2}\right)}\right)\right)}{t} \]
      6. unpow285.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, y \cdot \left(0.5 \cdot \color{blue}{\left(z \cdot z\right)}\right)\right)\right)}{t} \]
    6. Simplified85.2%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, z, y \cdot \left(0.5 \cdot \left(z \cdot z\right)\right)\right)}\right)}{t} \]
    7. Taylor expanded in t around 0 85.2%

      \[\leadsto x - \color{blue}{\frac{\log \left(1 + \left(0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z\right)\right)}{t}} \]
    8. Step-by-step derivation
      1. log1p-def85.2%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z\right)}}{t} \]
      2. associate-*r*85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(0.5 \cdot y\right) \cdot {z}^{2}} + y \cdot z\right)}{t} \]
      3. *-commutative85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(y \cdot 0.5\right)} \cdot {z}^{2} + y \cdot z\right)}{t} \]
      4. associate-*r*85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(0.5 \cdot {z}^{2}\right)} + y \cdot z\right)}{t} \]
      5. distribute-lft-in85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(0.5 \cdot {z}^{2} + z\right)}\right)}{t} \]
      6. +-commutative85.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\left(z + 0.5 \cdot {z}^{2}\right)}\right)}{t} \]
      7. unpow285.2%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \left(z + 0.5 \cdot \color{blue}{\left(z \cdot z\right)}\right)\right)}{t} \]
    9. Simplified85.2%

      \[\leadsto x - \color{blue}{\frac{\mathsf{log1p}\left(y \cdot \left(z + 0.5 \cdot \left(z \cdot z\right)\right)\right)}{t}} \]
    10. Taylor expanded in z around 0 79.7%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z}\right)}{t} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification86.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;e^{z} \leq 1:\\ \;\;\;\;x - \frac{y}{\frac{t}{\mathsf{expm1}\left(z\right)}}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{\mathsf{log1p}\left(y \cdot z\right)}{t}\\ \end{array} \]

Alternative 5: 86.3% accurate, 2.0× speedup?

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

\\
x - \frac{y}{\frac{t}{\mathsf{expm1}\left(z\right)}}
\end{array}
Derivation
  1. Initial program 63.7%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. sub-neg63.7%

      \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
    2. associate-+l+79.1%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
    3. cancel-sign-sub79.1%

      \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
    4. log1p-def83.8%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
    5. cancel-sign-sub83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
    6. +-commutative83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    7. unsub-neg83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
    8. *-rgt-identity83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    9. distribute-lft-out--83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    10. expm1-def97.7%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified97.7%

    \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
  4. Taylor expanded in y around 0 76.2%

    \[\leadsto x - \color{blue}{\frac{y \cdot \left(e^{z} - 1\right)}{t}} \]
  5. Step-by-step derivation
    1. associate-/l*76.2%

      \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{e^{z} - 1}}} \]
    2. expm1-def84.9%

      \[\leadsto x - \frac{y}{\frac{t}{\color{blue}{\mathsf{expm1}\left(z\right)}}} \]
  6. Simplified84.9%

    \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{\mathsf{expm1}\left(z\right)}}} \]
  7. Final simplification84.9%

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

Alternative 6: 86.1% accurate, 14.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -1.2:\\ \;\;\;\;x + \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{y}{\frac{t}{z + 0.5 \cdot \left(z \cdot z\right)}}\\ \end{array} \end{array} \]
(FPCore (x y z t)
 :precision binary64
 (if (<= z -1.2) (+ x (/ y t)) (- x (/ y (/ t (+ z (* 0.5 (* z z))))))))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -1.2) {
		tmp = x + (y / t);
	} else {
		tmp = x - (y / (t / (z + (0.5 * (z * z)))));
	}
	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 <= (-1.2d0)) then
        tmp = x + (y / t)
    else
        tmp = x - (y / (t / (z + (0.5d0 * (z * z)))))
    end if
    code = tmp
end function
public static double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -1.2) {
		tmp = x + (y / t);
	} else {
		tmp = x - (y / (t / (z + (0.5 * (z * z)))));
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -1.2:
		tmp = x + (y / t)
	else:
		tmp = x - (y / (t / (z + (0.5 * (z * z)))))
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -1.2)
		tmp = Float64(x + Float64(y / t));
	else
		tmp = Float64(x - Float64(y / Float64(t / Float64(z + Float64(0.5 * Float64(z * z))))));
	end
	return tmp
end
function tmp_2 = code(x, y, z, t)
	tmp = 0.0;
	if (z <= -1.2)
		tmp = x + (y / t);
	else
		tmp = x - (y / (t / (z + (0.5 * (z * z)))));
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[z, -1.2], N[(x + N[(y / t), $MachinePrecision]), $MachinePrecision], N[(x - N[(y / N[(t / N[(z + N[(0.5 * N[(z * z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -1.2:\\
\;\;\;\;x + \frac{y}{t}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -1.19999999999999996

    1. Initial program 84.1%

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

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+84.1%

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

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def99.8%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative99.8%

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

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in y around 0 76.6%

      \[\leadsto \color{blue}{x + y \cdot \left(\frac{1}{t} - \frac{e^{z}}{t}\right)} \]
    5. Taylor expanded in z around 0 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\left(\frac{1}{t} + \frac{z}{t}\right)}\right) \]
    6. Taylor expanded in z around inf 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\frac{z}{t}}\right) \]
    7. Taylor expanded in z around 0 76.7%

      \[\leadsto x + \color{blue}{\frac{y}{t}} \]

    if -1.19999999999999996 < z

    1. Initial program 55.7%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg55.7%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+77.1%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub77.1%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def77.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def96.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified96.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in z around 0 97.5%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{0.5 \cdot \left(y \cdot {z}^{2}\right) + y \cdot z}\right)}{t} \]
    5. Step-by-step derivation
      1. +-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot z + 0.5 \cdot \left(y \cdot {z}^{2}\right)}\right)}{t} \]
      2. fma-def97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, z, 0.5 \cdot \left(y \cdot {z}^{2}\right)\right)}\right)}{t} \]
      3. *-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, \color{blue}{\left(y \cdot {z}^{2}\right) \cdot 0.5}\right)\right)}{t} \]
      4. associate-*l*97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, \color{blue}{y \cdot \left({z}^{2} \cdot 0.5\right)}\right)\right)}{t} \]
      5. *-commutative97.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, y \cdot \color{blue}{\left(0.5 \cdot {z}^{2}\right)}\right)\right)}{t} \]
      6. unpow297.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\mathsf{fma}\left(y, z, y \cdot \left(0.5 \cdot \color{blue}{\left(z \cdot z\right)}\right)\right)\right)}{t} \]
    6. Simplified97.5%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\mathsf{fma}\left(y, z, y \cdot \left(0.5 \cdot \left(z \cdot z\right)\right)\right)}\right)}{t} \]
    7. Taylor expanded in y around 0 87.1%

      \[\leadsto x - \color{blue}{\frac{y \cdot \left(z + 0.5 \cdot {z}^{2}\right)}{t}} \]
    8. Step-by-step derivation
      1. associate-/l*88.7%

        \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{z + 0.5 \cdot {z}^{2}}}} \]
      2. unpow288.7%

        \[\leadsto x - \frac{y}{\frac{t}{z + 0.5 \cdot \color{blue}{\left(z \cdot z\right)}}} \]
    9. Simplified88.7%

      \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{z + 0.5 \cdot \left(z \cdot z\right)}}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification85.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -1.2:\\ \;\;\;\;x + \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{y}{\frac{t}{z + 0.5 \cdot \left(z \cdot z\right)}}\\ \end{array} \]

Alternative 7: 82.4% accurate, 23.3× speedup?

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

\\
\begin{array}{l}
\mathbf{if}\;z \leq -1:\\
\;\;\;\;x + \frac{y}{t}\\

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


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

    1. Initial program 84.1%

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

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+84.1%

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

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def99.8%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative99.8%

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

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in y around 0 76.6%

      \[\leadsto \color{blue}{x + y \cdot \left(\frac{1}{t} - \frac{e^{z}}{t}\right)} \]
    5. Taylor expanded in z around 0 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\left(\frac{1}{t} + \frac{z}{t}\right)}\right) \]
    6. Taylor expanded in z around inf 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\frac{z}{t}}\right) \]
    7. Taylor expanded in z around 0 76.7%

      \[\leadsto x + \color{blue}{\frac{y}{t}} \]

    if -1 < z

    1. Initial program 55.7%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg55.7%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+77.1%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub77.1%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def77.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def96.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified96.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in z around 0 86.9%

      \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
    5. Step-by-step derivation
      1. associate-/l*88.5%

        \[\leadsto x - \color{blue}{\frac{y}{\frac{t}{z}}} \]
      2. associate-/r/84.6%

        \[\leadsto x - \color{blue}{\frac{y}{t} \cdot z} \]
    6. Simplified84.6%

      \[\leadsto x - \color{blue}{\frac{y}{t} \cdot z} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification82.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -1:\\ \;\;\;\;x + \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - z \cdot \frac{y}{t}\\ \end{array} \]

Alternative 8: 84.9% accurate, 23.3× speedup?

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

\\
\begin{array}{l}
\mathbf{if}\;z \leq -1:\\
\;\;\;\;x + \frac{y}{t}\\

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


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

    1. Initial program 84.1%

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

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+84.1%

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

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def99.8%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative99.8%

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

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in y around 0 76.6%

      \[\leadsto \color{blue}{x + y \cdot \left(\frac{1}{t} - \frac{e^{z}}{t}\right)} \]
    5. Taylor expanded in z around 0 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\left(\frac{1}{t} + \frac{z}{t}\right)}\right) \]
    6. Taylor expanded in z around inf 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\frac{z}{t}}\right) \]
    7. Taylor expanded in z around 0 76.7%

      \[\leadsto x + \color{blue}{\frac{y}{t}} \]

    if -1 < z

    1. Initial program 55.7%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg55.7%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+77.1%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub77.1%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def77.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def96.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified96.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in z around 0 86.9%

      \[\leadsto x - \color{blue}{\frac{y \cdot z}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification84.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -1:\\ \;\;\;\;x + \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - \frac{y \cdot z}{t}\\ \end{array} \]

Alternative 9: 86.0% accurate, 23.3× speedup?

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

\\
\begin{array}{l}
\mathbf{if}\;z \leq -1:\\
\;\;\;\;x + \frac{y}{t}\\

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


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

    1. Initial program 84.1%

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

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+84.1%

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

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def99.8%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative99.8%

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

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def99.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified99.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in y around 0 76.6%

      \[\leadsto \color{blue}{x + y \cdot \left(\frac{1}{t} - \frac{e^{z}}{t}\right)} \]
    5. Taylor expanded in z around 0 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\left(\frac{1}{t} + \frac{z}{t}\right)}\right) \]
    6. Taylor expanded in z around inf 35.3%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\frac{z}{t}}\right) \]
    7. Taylor expanded in z around 0 76.7%

      \[\leadsto x + \color{blue}{\frac{y}{t}} \]

    if -1 < z

    1. Initial program 55.7%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg55.7%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+77.1%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub77.1%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def77.5%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--77.5%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def96.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified96.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in y around 0 76.0%

      \[\leadsto \color{blue}{x + y \cdot \left(\frac{1}{t} - \frac{e^{z}}{t}\right)} \]
    5. Taylor expanded in z around 0 88.5%

      \[\leadsto x + y \cdot \color{blue}{\left(-1 \cdot \frac{z}{t}\right)} \]
    6. Step-by-step derivation
      1. associate-*r/88.5%

        \[\leadsto x + y \cdot \color{blue}{\frac{-1 \cdot z}{t}} \]
      2. mul-1-neg88.5%

        \[\leadsto x + y \cdot \frac{\color{blue}{-z}}{t} \]
    7. Simplified88.5%

      \[\leadsto x + y \cdot \color{blue}{\frac{-z}{t}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification85.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -1:\\ \;\;\;\;x + \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x - y \cdot \frac{z}{t}\\ \end{array} \]

Alternative 10: 74.1% accurate, 29.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;z \leq -3 \cdot 10^{-16}:\\ \;\;\;\;x + \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \end{array} \]
(FPCore (x y z t) :precision binary64 (if (<= z -3e-16) (+ x (/ y t)) x))
double code(double x, double y, double z, double t) {
	double tmp;
	if (z <= -3e-16) {
		tmp = x + (y / 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 (z <= (-3d-16)) then
        tmp = x + (y / 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 (z <= -3e-16) {
		tmp = x + (y / t);
	} else {
		tmp = x;
	}
	return tmp;
}
def code(x, y, z, t):
	tmp = 0
	if z <= -3e-16:
		tmp = x + (y / t)
	else:
		tmp = x
	return tmp
function code(x, y, z, t)
	tmp = 0.0
	if (z <= -3e-16)
		tmp = Float64(x + Float64(y / t));
	else
		tmp = x;
	end
	return tmp
end
function tmp_2 = code(x, y, z, t)
	tmp = 0.0;
	if (z <= -3e-16)
		tmp = x + (y / t);
	else
		tmp = x;
	end
	tmp_2 = tmp;
end
code[x_, y_, z_, t_] := If[LessEqual[z, -3e-16], N[(x + N[(y / t), $MachinePrecision]), $MachinePrecision], x]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;z \leq -3 \cdot 10^{-16}:\\
\;\;\;\;x + \frac{y}{t}\\

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


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if z < -2.99999999999999994e-16

    1. Initial program 81.9%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg81.9%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+81.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub81.9%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def98.3%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub98.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative98.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg98.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity98.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--98.3%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. 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 y around 0 75.7%

      \[\leadsto \color{blue}{x + y \cdot \left(\frac{1}{t} - \frac{e^{z}}{t}\right)} \]
    5. Taylor expanded in z around 0 35.5%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\left(\frac{1}{t} + \frac{z}{t}\right)}\right) \]
    6. Taylor expanded in z around inf 34.6%

      \[\leadsto x + y \cdot \left(\frac{1}{t} - \color{blue}{\frac{z}{t}}\right) \]
    7. Taylor expanded in z around 0 74.9%

      \[\leadsto x + \color{blue}{\frac{y}{t}} \]

    if -2.99999999999999994e-16 < z

    1. Initial program 56.2%

      \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
    2. Step-by-step derivation
      1. sub-neg56.2%

        \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
      2. associate-+l+77.9%

        \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
      3. cancel-sign-sub77.9%

        \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
      4. log1p-def77.9%

        \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
      5. cancel-sign-sub77.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
      6. +-commutative77.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
      7. unsub-neg77.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
      8. *-rgt-identity77.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
      9. distribute-lft-out--77.9%

        \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
      10. expm1-def96.8%

        \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
    3. Simplified96.8%

      \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
    4. Taylor expanded in x around inf 77.4%

      \[\leadsto \color{blue}{x} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification76.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;z \leq -3 \cdot 10^{-16}:\\ \;\;\;\;x + \frac{y}{t}\\ \mathbf{else}:\\ \;\;\;\;x\\ \end{array} \]

Alternative 11: 70.4% accurate, 211.0× speedup?

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

\\
x
\end{array}
Derivation
  1. Initial program 63.7%

    \[x - \frac{\log \left(\left(1 - y\right) + y \cdot e^{z}\right)}{t} \]
  2. Step-by-step derivation
    1. sub-neg63.7%

      \[\leadsto x - \frac{\log \left(\color{blue}{\left(1 + \left(-y\right)\right)} + y \cdot e^{z}\right)}{t} \]
    2. associate-+l+79.1%

      \[\leadsto x - \frac{\log \color{blue}{\left(1 + \left(\left(-y\right) + y \cdot e^{z}\right)\right)}}{t} \]
    3. cancel-sign-sub79.1%

      \[\leadsto x - \frac{\log \left(1 + \color{blue}{\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}\right)}{t} \]
    4. log1p-def83.8%

      \[\leadsto x - \frac{\color{blue}{\mathsf{log1p}\left(\left(-y\right) - \left(-y\right) \cdot e^{z}\right)}}{t} \]
    5. cancel-sign-sub83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{\left(-y\right) + y \cdot e^{z}}\right)}{t} \]
    6. +-commutative83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} + \left(-y\right)}\right)}{t} \]
    7. unsub-neg83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot e^{z} - y}\right)}{t} \]
    8. *-rgt-identity83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot e^{z} - \color{blue}{y \cdot 1}\right)}{t} \]
    9. distribute-lft-out--83.8%

      \[\leadsto x - \frac{\mathsf{log1p}\left(\color{blue}{y \cdot \left(e^{z} - 1\right)}\right)}{t} \]
    10. expm1-def97.7%

      \[\leadsto x - \frac{\mathsf{log1p}\left(y \cdot \color{blue}{\mathsf{expm1}\left(z\right)}\right)}{t} \]
  3. Simplified97.7%

    \[\leadsto \color{blue}{x - \frac{\mathsf{log1p}\left(y \cdot \mathsf{expm1}\left(z\right)\right)}{t}} \]
  4. Taylor expanded in x around inf 73.3%

    \[\leadsto \color{blue}{x} \]
  5. Final simplification73.3%

    \[\leadsto x \]

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 2023279 
(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)))