NMSE Section 6.1 mentioned, A

Percentage Accurate: 72.6% → 98.8%
Time: 11.2s
Alternatives: 8
Speedup: 2.0×

Specification

?
\[\begin{array}{l} \\ \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (/
  (-
   (* (+ 1.0 (/ 1.0 eps)) (exp (- (* (- 1.0 eps) x))))
   (* (- (/ 1.0 eps) 1.0) (exp (- (* (+ 1.0 eps) x)))))
  2.0))
double code(double x, double eps) {
	return (((1.0 + (1.0 / eps)) * exp(-((1.0 - eps) * x))) - (((1.0 / eps) - 1.0) * exp(-((1.0 + eps) * x)))) / 2.0;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = (((1.0d0 + (1.0d0 / eps)) * exp(-((1.0d0 - eps) * x))) - (((1.0d0 / eps) - 1.0d0) * exp(-((1.0d0 + eps) * x)))) / 2.0d0
end function
public static double code(double x, double eps) {
	return (((1.0 + (1.0 / eps)) * Math.exp(-((1.0 - eps) * x))) - (((1.0 / eps) - 1.0) * Math.exp(-((1.0 + eps) * x)))) / 2.0;
}
def code(x, eps):
	return (((1.0 + (1.0 / eps)) * math.exp(-((1.0 - eps) * x))) - (((1.0 / eps) - 1.0) * math.exp(-((1.0 + eps) * x)))) / 2.0
function code(x, eps)
	return Float64(Float64(Float64(Float64(1.0 + Float64(1.0 / eps)) * exp(Float64(-Float64(Float64(1.0 - eps) * x)))) - Float64(Float64(Float64(1.0 / eps) - 1.0) * exp(Float64(-Float64(Float64(1.0 + eps) * x))))) / 2.0)
end
function tmp = code(x, eps)
	tmp = (((1.0 + (1.0 / eps)) * exp(-((1.0 - eps) * x))) - (((1.0 / eps) - 1.0) * exp(-((1.0 + eps) * x)))) / 2.0;
end
code[x_, eps_] := N[(N[(N[(N[(1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision] * N[Exp[(-N[(N[(1.0 - eps), $MachinePrecision] * x), $MachinePrecision])], $MachinePrecision]), $MachinePrecision] - N[(N[(N[(1.0 / eps), $MachinePrecision] - 1.0), $MachinePrecision] * N[Exp[(-N[(N[(1.0 + eps), $MachinePrecision] * x), $MachinePrecision])], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2}
\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 8 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: 72.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (/
  (-
   (* (+ 1.0 (/ 1.0 eps)) (exp (- (* (- 1.0 eps) x))))
   (* (- (/ 1.0 eps) 1.0) (exp (- (* (+ 1.0 eps) x)))))
  2.0))
double code(double x, double eps) {
	return (((1.0 + (1.0 / eps)) * exp(-((1.0 - eps) * x))) - (((1.0 / eps) - 1.0) * exp(-((1.0 + eps) * x)))) / 2.0;
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = (((1.0d0 + (1.0d0 / eps)) * exp(-((1.0d0 - eps) * x))) - (((1.0d0 / eps) - 1.0d0) * exp(-((1.0d0 + eps) * x)))) / 2.0d0
end function
public static double code(double x, double eps) {
	return (((1.0 + (1.0 / eps)) * Math.exp(-((1.0 - eps) * x))) - (((1.0 / eps) - 1.0) * Math.exp(-((1.0 + eps) * x)))) / 2.0;
}
def code(x, eps):
	return (((1.0 + (1.0 / eps)) * math.exp(-((1.0 - eps) * x))) - (((1.0 / eps) - 1.0) * math.exp(-((1.0 + eps) * x)))) / 2.0
function code(x, eps)
	return Float64(Float64(Float64(Float64(1.0 + Float64(1.0 / eps)) * exp(Float64(-Float64(Float64(1.0 - eps) * x)))) - Float64(Float64(Float64(1.0 / eps) - 1.0) * exp(Float64(-Float64(Float64(1.0 + eps) * x))))) / 2.0)
end
function tmp = code(x, eps)
	tmp = (((1.0 + (1.0 / eps)) * exp(-((1.0 - eps) * x))) - (((1.0 / eps) - 1.0) * exp(-((1.0 + eps) * x)))) / 2.0;
end
code[x_, eps_] := N[(N[(N[(N[(1.0 + N[(1.0 / eps), $MachinePrecision]), $MachinePrecision] * N[Exp[(-N[(N[(1.0 - eps), $MachinePrecision] * x), $MachinePrecision])], $MachinePrecision]), $MachinePrecision] - N[(N[(N[(1.0 / eps), $MachinePrecision] - 1.0), $MachinePrecision] * N[Exp[(-N[(N[(1.0 + eps), $MachinePrecision] * x), $MachinePrecision])], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2}
\end{array}

Alternative 1: 98.8% accurate, 2.0× speedup?

\[\begin{array}{l} eps_m = \left|\varepsilon\right| \\ \begin{array}{l} \mathbf{if}\;eps\_m \leq 1:\\ \;\;\;\;\frac{2 \cdot e^{-x}}{2}\\ \mathbf{else}:\\ \;\;\;\;\frac{2 \cdot \cosh \left(x \cdot eps\_m\right)}{2}\\ \end{array} \end{array} \]
eps_m = (fabs.f64 eps)
(FPCore (x eps_m)
 :precision binary64
 (if (<= eps_m 1.0)
   (/ (* 2.0 (exp (- x))) 2.0)
   (/ (* 2.0 (cosh (* x eps_m))) 2.0)))
eps_m = fabs(eps);
double code(double x, double eps_m) {
	double tmp;
	if (eps_m <= 1.0) {
		tmp = (2.0 * exp(-x)) / 2.0;
	} else {
		tmp = (2.0 * cosh((x * eps_m))) / 2.0;
	}
	return tmp;
}
eps_m = abs(eps)
real(8) function code(x, eps_m)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps_m
    real(8) :: tmp
    if (eps_m <= 1.0d0) then
        tmp = (2.0d0 * exp(-x)) / 2.0d0
    else
        tmp = (2.0d0 * cosh((x * eps_m))) / 2.0d0
    end if
    code = tmp
end function
eps_m = Math.abs(eps);
public static double code(double x, double eps_m) {
	double tmp;
	if (eps_m <= 1.0) {
		tmp = (2.0 * Math.exp(-x)) / 2.0;
	} else {
		tmp = (2.0 * Math.cosh((x * eps_m))) / 2.0;
	}
	return tmp;
}
eps_m = math.fabs(eps)
def code(x, eps_m):
	tmp = 0
	if eps_m <= 1.0:
		tmp = (2.0 * math.exp(-x)) / 2.0
	else:
		tmp = (2.0 * math.cosh((x * eps_m))) / 2.0
	return tmp
eps_m = abs(eps)
function code(x, eps_m)
	tmp = 0.0
	if (eps_m <= 1.0)
		tmp = Float64(Float64(2.0 * exp(Float64(-x))) / 2.0);
	else
		tmp = Float64(Float64(2.0 * cosh(Float64(x * eps_m))) / 2.0);
	end
	return tmp
end
eps_m = abs(eps);
function tmp_2 = code(x, eps_m)
	tmp = 0.0;
	if (eps_m <= 1.0)
		tmp = (2.0 * exp(-x)) / 2.0;
	else
		tmp = (2.0 * cosh((x * eps_m))) / 2.0;
	end
	tmp_2 = tmp;
end
eps_m = N[Abs[eps], $MachinePrecision]
code[x_, eps$95$m_] := If[LessEqual[eps$95$m, 1.0], N[(N[(2.0 * N[Exp[(-x)], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision], N[(N[(2.0 * N[Cosh[N[(x * eps$95$m), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]]
\begin{array}{l}
eps_m = \left|\varepsilon\right|

\\
\begin{array}{l}
\mathbf{if}\;eps\_m \leq 1:\\
\;\;\;\;\frac{2 \cdot e^{-x}}{2}\\

\mathbf{else}:\\
\;\;\;\;\frac{2 \cdot \cosh \left(x \cdot eps\_m\right)}{2}\\


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

    1. Initial program 62.6%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified56.3%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 99.5%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around 0 79.6%

      \[\leadsto \frac{\color{blue}{2 \cdot e^{-1 \cdot x}}}{2} \]
    6. Step-by-step derivation
      1. neg-mul-179.6%

        \[\leadsto \frac{2 \cdot e^{\color{blue}{-x}}}{2} \]
    7. Simplified79.6%

      \[\leadsto \frac{\color{blue}{2 \cdot e^{-x}}}{2} \]

    if 1 < eps

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified82.8%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 100.0%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around inf 100.0%

      \[\leadsto \frac{e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    6. Step-by-step derivation
      1. associate-*r*100.0%

        \[\leadsto \frac{e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
      2. neg-mul-1100.0%

        \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right)} \cdot x} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    7. Simplified100.0%

      \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    8. Taylor expanded in eps around inf 100.0%

      \[\leadsto \frac{e^{\left(-\varepsilon\right) \cdot x} + e^{\color{blue}{\varepsilon \cdot x}}}{2} \]
    9. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto \frac{e^{\left(-\varepsilon\right) \cdot x} + e^{\color{blue}{x \cdot \varepsilon}}}{2} \]
    10. Simplified100.0%

      \[\leadsto \frac{e^{\left(-\varepsilon\right) \cdot x} + e^{\color{blue}{x \cdot \varepsilon}}}{2} \]
    11. Step-by-step derivation
      1. +-commutative100.0%

        \[\leadsto \frac{\color{blue}{e^{x \cdot \varepsilon} + e^{\left(-\varepsilon\right) \cdot x}}}{2} \]
      2. distribute-lft-neg-out100.0%

        \[\leadsto \frac{e^{x \cdot \varepsilon} + e^{\color{blue}{-\varepsilon \cdot x}}}{2} \]
      3. *-commutative100.0%

        \[\leadsto \frac{e^{x \cdot \varepsilon} + e^{-\color{blue}{x \cdot \varepsilon}}}{2} \]
      4. cosh-undef100.0%

        \[\leadsto \frac{\color{blue}{2 \cdot \cosh \left(x \cdot \varepsilon\right)}}{2} \]
    12. Applied egg-rr100.0%

      \[\leadsto \frac{\color{blue}{2 \cdot \cosh \left(x \cdot \varepsilon\right)}}{2} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 2: 98.8% accurate, 1.1× speedup?

\[\begin{array}{l} eps_m = \left|\varepsilon\right| \\ \frac{e^{x \cdot \left(-1 - eps\_m\right)} + e^{x \cdot \left(-1 + eps\_m\right)}}{2} \end{array} \]
eps_m = (fabs.f64 eps)
(FPCore (x eps_m)
 :precision binary64
 (/ (+ (exp (* x (- -1.0 eps_m))) (exp (* x (+ -1.0 eps_m)))) 2.0))
eps_m = fabs(eps);
double code(double x, double eps_m) {
	return (exp((x * (-1.0 - eps_m))) + exp((x * (-1.0 + eps_m)))) / 2.0;
}
eps_m = abs(eps)
real(8) function code(x, eps_m)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps_m
    code = (exp((x * ((-1.0d0) - eps_m))) + exp((x * ((-1.0d0) + eps_m)))) / 2.0d0
end function
eps_m = Math.abs(eps);
public static double code(double x, double eps_m) {
	return (Math.exp((x * (-1.0 - eps_m))) + Math.exp((x * (-1.0 + eps_m)))) / 2.0;
}
eps_m = math.fabs(eps)
def code(x, eps_m):
	return (math.exp((x * (-1.0 - eps_m))) + math.exp((x * (-1.0 + eps_m)))) / 2.0
eps_m = abs(eps)
function code(x, eps_m)
	return Float64(Float64(exp(Float64(x * Float64(-1.0 - eps_m))) + exp(Float64(x * Float64(-1.0 + eps_m)))) / 2.0)
end
eps_m = abs(eps);
function tmp = code(x, eps_m)
	tmp = (exp((x * (-1.0 - eps_m))) + exp((x * (-1.0 + eps_m)))) / 2.0;
end
eps_m = N[Abs[eps], $MachinePrecision]
code[x_, eps$95$m_] := N[(N[(N[Exp[N[(x * N[(-1.0 - eps$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] + N[Exp[N[(x * N[(-1.0 + eps$95$m), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]
\begin{array}{l}
eps_m = \left|\varepsilon\right|

\\
\frac{e^{x \cdot \left(-1 - eps\_m\right)} + e^{x \cdot \left(-1 + eps\_m\right)}}{2}
\end{array}
Derivation
  1. Initial program 72.4%

    \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
  2. Simplified63.3%

    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
  3. Add Preprocessing
  4. Taylor expanded in eps around inf 99.6%

    \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
  5. Final simplification99.6%

    \[\leadsto \frac{e^{x \cdot \left(-1 - \varepsilon\right)} + e^{x \cdot \left(-1 + \varepsilon\right)}}{2} \]
  6. Add Preprocessing

Alternative 3: 73.8% accurate, 2.0× speedup?

\[\begin{array}{l} eps_m = \left|\varepsilon\right| \\ \begin{array}{l} \mathbf{if}\;eps\_m \leq 46:\\ \;\;\;\;\frac{2 \cdot e^{-x}}{2}\\ \mathbf{elif}\;eps\_m \leq 2.2 \cdot 10^{+115}:\\ \;\;\;\;\frac{1 + e^{x}}{2}\\ \mathbf{elif}\;eps\_m \leq 6.6 \cdot 10^{+125}:\\ \;\;\;\;1 + x \cdot \left(x \cdot \left(0.25 + x \cdot -0.08333333333333333\right) - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{2 + \frac{x + eps\_m \cdot \left(x \cdot \left(eps\_m + -2\right)\right)}{eps\_m}}{2}\\ \end{array} \end{array} \]
eps_m = (fabs.f64 eps)
(FPCore (x eps_m)
 :precision binary64
 (if (<= eps_m 46.0)
   (/ (* 2.0 (exp (- x))) 2.0)
   (if (<= eps_m 2.2e+115)
     (/ (+ 1.0 (exp x)) 2.0)
     (if (<= eps_m 6.6e+125)
       (+ 1.0 (* x (- (* x (+ 0.25 (* x -0.08333333333333333))) 0.5)))
       (/ (+ 2.0 (/ (+ x (* eps_m (* x (+ eps_m -2.0)))) eps_m)) 2.0)))))
eps_m = fabs(eps);
double code(double x, double eps_m) {
	double tmp;
	if (eps_m <= 46.0) {
		tmp = (2.0 * exp(-x)) / 2.0;
	} else if (eps_m <= 2.2e+115) {
		tmp = (1.0 + exp(x)) / 2.0;
	} else if (eps_m <= 6.6e+125) {
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5));
	} else {
		tmp = (2.0 + ((x + (eps_m * (x * (eps_m + -2.0)))) / eps_m)) / 2.0;
	}
	return tmp;
}
eps_m = abs(eps)
real(8) function code(x, eps_m)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps_m
    real(8) :: tmp
    if (eps_m <= 46.0d0) then
        tmp = (2.0d0 * exp(-x)) / 2.0d0
    else if (eps_m <= 2.2d+115) then
        tmp = (1.0d0 + exp(x)) / 2.0d0
    else if (eps_m <= 6.6d+125) then
        tmp = 1.0d0 + (x * ((x * (0.25d0 + (x * (-0.08333333333333333d0)))) - 0.5d0))
    else
        tmp = (2.0d0 + ((x + (eps_m * (x * (eps_m + (-2.0d0))))) / eps_m)) / 2.0d0
    end if
    code = tmp
end function
eps_m = Math.abs(eps);
public static double code(double x, double eps_m) {
	double tmp;
	if (eps_m <= 46.0) {
		tmp = (2.0 * Math.exp(-x)) / 2.0;
	} else if (eps_m <= 2.2e+115) {
		tmp = (1.0 + Math.exp(x)) / 2.0;
	} else if (eps_m <= 6.6e+125) {
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5));
	} else {
		tmp = (2.0 + ((x + (eps_m * (x * (eps_m + -2.0)))) / eps_m)) / 2.0;
	}
	return tmp;
}
eps_m = math.fabs(eps)
def code(x, eps_m):
	tmp = 0
	if eps_m <= 46.0:
		tmp = (2.0 * math.exp(-x)) / 2.0
	elif eps_m <= 2.2e+115:
		tmp = (1.0 + math.exp(x)) / 2.0
	elif eps_m <= 6.6e+125:
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5))
	else:
		tmp = (2.0 + ((x + (eps_m * (x * (eps_m + -2.0)))) / eps_m)) / 2.0
	return tmp
eps_m = abs(eps)
function code(x, eps_m)
	tmp = 0.0
	if (eps_m <= 46.0)
		tmp = Float64(Float64(2.0 * exp(Float64(-x))) / 2.0);
	elseif (eps_m <= 2.2e+115)
		tmp = Float64(Float64(1.0 + exp(x)) / 2.0);
	elseif (eps_m <= 6.6e+125)
		tmp = Float64(1.0 + Float64(x * Float64(Float64(x * Float64(0.25 + Float64(x * -0.08333333333333333))) - 0.5)));
	else
		tmp = Float64(Float64(2.0 + Float64(Float64(x + Float64(eps_m * Float64(x * Float64(eps_m + -2.0)))) / eps_m)) / 2.0);
	end
	return tmp
end
eps_m = abs(eps);
function tmp_2 = code(x, eps_m)
	tmp = 0.0;
	if (eps_m <= 46.0)
		tmp = (2.0 * exp(-x)) / 2.0;
	elseif (eps_m <= 2.2e+115)
		tmp = (1.0 + exp(x)) / 2.0;
	elseif (eps_m <= 6.6e+125)
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5));
	else
		tmp = (2.0 + ((x + (eps_m * (x * (eps_m + -2.0)))) / eps_m)) / 2.0;
	end
	tmp_2 = tmp;
end
eps_m = N[Abs[eps], $MachinePrecision]
code[x_, eps$95$m_] := If[LessEqual[eps$95$m, 46.0], N[(N[(2.0 * N[Exp[(-x)], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision], If[LessEqual[eps$95$m, 2.2e+115], N[(N[(1.0 + N[Exp[x], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision], If[LessEqual[eps$95$m, 6.6e+125], N[(1.0 + N[(x * N[(N[(x * N[(0.25 + N[(x * -0.08333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(2.0 + N[(N[(x + N[(eps$95$m * N[(x * N[(eps$95$m + -2.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / eps$95$m), $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]]]]
\begin{array}{l}
eps_m = \left|\varepsilon\right|

\\
\begin{array}{l}
\mathbf{if}\;eps\_m \leq 46:\\
\;\;\;\;\frac{2 \cdot e^{-x}}{2}\\

\mathbf{elif}\;eps\_m \leq 2.2 \cdot 10^{+115}:\\
\;\;\;\;\frac{1 + e^{x}}{2}\\

\mathbf{elif}\;eps\_m \leq 6.6 \cdot 10^{+125}:\\
\;\;\;\;1 + x \cdot \left(x \cdot \left(0.25 + x \cdot -0.08333333333333333\right) - 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{2 + \frac{x + eps\_m \cdot \left(x \cdot \left(eps\_m + -2\right)\right)}{eps\_m}}{2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if eps < 46

    1. Initial program 62.8%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified56.5%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 99.5%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around 0 79.7%

      \[\leadsto \frac{\color{blue}{2 \cdot e^{-1 \cdot x}}}{2} \]
    6. Step-by-step derivation
      1. neg-mul-179.7%

        \[\leadsto \frac{2 \cdot e^{\color{blue}{-x}}}{2} \]
    7. Simplified79.7%

      \[\leadsto \frac{\color{blue}{2 \cdot e^{-x}}}{2} \]

    if 46 < eps < 2.2e115

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified68.6%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 100.0%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around inf 100.0%

      \[\leadsto \frac{e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    6. Step-by-step derivation
      1. associate-*r*100.0%

        \[\leadsto \frac{e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
      2. neg-mul-1100.0%

        \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right)} \cdot x} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    7. Simplified100.0%

      \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    8. Taylor expanded in eps around 0 54.4%

      \[\leadsto \frac{\color{blue}{1 + e^{-1 \cdot x}}}{2} \]
    9. Step-by-step derivation
      1. neg-mul-154.4%

        \[\leadsto \frac{1 + e^{\color{blue}{-x}}}{2} \]
    10. Simplified54.4%

      \[\leadsto \frac{\color{blue}{1 + e^{-x}}}{2} \]
    11. Step-by-step derivation
      1. frac-2neg54.4%

        \[\leadsto \color{blue}{\frac{-\left(1 + e^{-x}\right)}{-2}} \]
      2. distribute-frac-neg54.4%

        \[\leadsto \color{blue}{-\frac{1 + e^{-x}}{-2}} \]
      3. add-sqr-sqrt35.3%

        \[\leadsto -\frac{1 + e^{\color{blue}{\sqrt{-x} \cdot \sqrt{-x}}}}{-2} \]
      4. sqrt-unprod100.0%

        \[\leadsto -\frac{1 + e^{\color{blue}{\sqrt{\left(-x\right) \cdot \left(-x\right)}}}}{-2} \]
      5. sqr-neg100.0%

        \[\leadsto -\frac{1 + e^{\sqrt{\color{blue}{x \cdot x}}}}{-2} \]
      6. sqrt-unprod64.7%

        \[\leadsto -\frac{1 + e^{\color{blue}{\sqrt{x} \cdot \sqrt{x}}}}{-2} \]
      7. add-sqr-sqrt82.9%

        \[\leadsto -\frac{1 + e^{\color{blue}{x}}}{-2} \]
      8. metadata-eval82.9%

        \[\leadsto -\frac{1 + e^{x}}{\color{blue}{-2}} \]
    12. Applied egg-rr82.9%

      \[\leadsto \color{blue}{-\frac{1 + e^{x}}{-2}} \]
    13. Step-by-step derivation
      1. distribute-neg-frac282.9%

        \[\leadsto \color{blue}{\frac{1 + e^{x}}{--2}} \]
      2. metadata-eval82.9%

        \[\leadsto \frac{1 + e^{x}}{\color{blue}{2}} \]
    14. Simplified82.9%

      \[\leadsto \color{blue}{\frac{1 + e^{x}}{2}} \]

    if 2.2e115 < eps < 6.60000000000000011e125

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified100.0%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 100.0%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around inf 100.0%

      \[\leadsto \frac{e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    6. Step-by-step derivation
      1. associate-*r*100.0%

        \[\leadsto \frac{e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
      2. neg-mul-1100.0%

        \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right)} \cdot x} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    7. Simplified100.0%

      \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    8. Taylor expanded in eps around 0 100.0%

      \[\leadsto \frac{\color{blue}{1 + e^{-1 \cdot x}}}{2} \]
    9. Step-by-step derivation
      1. neg-mul-1100.0%

        \[\leadsto \frac{1 + e^{\color{blue}{-x}}}{2} \]
    10. Simplified100.0%

      \[\leadsto \frac{\color{blue}{1 + e^{-x}}}{2} \]
    11. Taylor expanded in x around 0 100.0%

      \[\leadsto \color{blue}{1 + x \cdot \left(x \cdot \left(0.25 + -0.08333333333333333 \cdot x\right) - 0.5\right)} \]

    if 6.60000000000000011e125 < eps

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified100.0%

      \[\leadsto \color{blue}{\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{\left(1 - \varepsilon\right) \cdot \left(-x\right)} - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\left(1 + \varepsilon\right) \cdot \left(-x\right)}}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in x around 0 43.3%

      \[\leadsto \frac{\color{blue}{\left(1 + \frac{1}{\varepsilon}\right)} - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\left(1 + \varepsilon\right) \cdot \left(-x\right)}}{2} \]
    5. Step-by-step derivation
      1. *-commutative43.3%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\color{blue}{\left(-x\right) \cdot \left(1 + \varepsilon\right)}}}{2} \]
      2. +-commutative43.3%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\left(-x\right) \cdot \color{blue}{\left(\varepsilon + 1\right)}}}{2} \]
      3. distribute-rgt-in43.3%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\color{blue}{\varepsilon \cdot \left(-x\right) + 1 \cdot \left(-x\right)}}}{2} \]
      4. add-sqr-sqrt33.8%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\varepsilon \cdot \color{blue}{\left(\sqrt{-x} \cdot \sqrt{-x}\right)} + 1 \cdot \left(-x\right)}}{2} \]
      5. sqrt-unprod84.9%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\varepsilon \cdot \color{blue}{\sqrt{\left(-x\right) \cdot \left(-x\right)}} + 1 \cdot \left(-x\right)}}{2} \]
      6. sqr-neg84.9%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\varepsilon \cdot \sqrt{\color{blue}{x \cdot x}} + 1 \cdot \left(-x\right)}}{2} \]
      7. sqrt-unprod64.3%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\varepsilon \cdot \color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} + 1 \cdot \left(-x\right)}}{2} \]
      8. add-sqr-sqrt70.7%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\varepsilon \cdot \color{blue}{x} + 1 \cdot \left(-x\right)}}{2} \]
      9. *-un-lft-identity70.7%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\varepsilon \cdot x + \color{blue}{\left(-x\right)}}}{2} \]
      10. unsub-neg70.7%

        \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\color{blue}{\varepsilon \cdot x - x}}}{2} \]
    6. Applied egg-rr70.7%

      \[\leadsto \frac{\left(1 + \frac{1}{\varepsilon}\right) - \left(\frac{1}{\varepsilon} + -1\right) \cdot e^{\color{blue}{\varepsilon \cdot x - x}}}{2} \]
    7. Taylor expanded in x around 0 41.1%

      \[\leadsto \frac{\color{blue}{2 + -1 \cdot \left(x \cdot \left(\left(\varepsilon - 1\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)}}{2} \]
    8. Step-by-step derivation
      1. mul-1-neg41.1%

        \[\leadsto \frac{2 + \color{blue}{\left(-x \cdot \left(\left(\varepsilon - 1\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)\right)}}{2} \]
      2. distribute-rgt-neg-in41.1%

        \[\leadsto \frac{2 + \color{blue}{x \cdot \left(-\left(\varepsilon - 1\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)}}{2} \]
      3. sub-neg41.1%

        \[\leadsto \frac{2 + x \cdot \left(-\color{blue}{\left(\varepsilon + \left(-1\right)\right)} \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)}{2} \]
      4. metadata-eval41.1%

        \[\leadsto \frac{2 + x \cdot \left(-\left(\varepsilon + \color{blue}{-1}\right) \cdot \left(\frac{1}{\varepsilon} - 1\right)\right)}{2} \]
      5. sub-neg41.1%

        \[\leadsto \frac{2 + x \cdot \left(-\left(\varepsilon + -1\right) \cdot \color{blue}{\left(\frac{1}{\varepsilon} + \left(-1\right)\right)}\right)}{2} \]
      6. metadata-eval41.1%

        \[\leadsto \frac{2 + x \cdot \left(-\left(\varepsilon + -1\right) \cdot \left(\frac{1}{\varepsilon} + \color{blue}{-1}\right)\right)}{2} \]
      7. distribute-rgt-neg-in41.1%

        \[\leadsto \frac{2 + x \cdot \color{blue}{\left(\left(\varepsilon + -1\right) \cdot \left(-\left(\frac{1}{\varepsilon} + -1\right)\right)\right)}}{2} \]
      8. +-commutative41.1%

        \[\leadsto \frac{2 + x \cdot \left(\color{blue}{\left(-1 + \varepsilon\right)} \cdot \left(-\left(\frac{1}{\varepsilon} + -1\right)\right)\right)}{2} \]
      9. neg-mul-141.1%

        \[\leadsto \frac{2 + x \cdot \left(\left(-1 + \varepsilon\right) \cdot \color{blue}{\left(-1 \cdot \left(\frac{1}{\varepsilon} + -1\right)\right)}\right)}{2} \]
      10. +-commutative41.1%

        \[\leadsto \frac{2 + x \cdot \left(\left(-1 + \varepsilon\right) \cdot \left(-1 \cdot \color{blue}{\left(-1 + \frac{1}{\varepsilon}\right)}\right)\right)}{2} \]
      11. distribute-rgt-in41.1%

        \[\leadsto \frac{2 + x \cdot \left(\left(-1 + \varepsilon\right) \cdot \color{blue}{\left(-1 \cdot -1 + \frac{1}{\varepsilon} \cdot -1\right)}\right)}{2} \]
      12. metadata-eval41.1%

        \[\leadsto \frac{2 + x \cdot \left(\left(-1 + \varepsilon\right) \cdot \left(\color{blue}{1} + \frac{1}{\varepsilon} \cdot -1\right)\right)}{2} \]
      13. associate-*l/41.1%

        \[\leadsto \frac{2 + x \cdot \left(\left(-1 + \varepsilon\right) \cdot \left(1 + \color{blue}{\frac{1 \cdot -1}{\varepsilon}}\right)\right)}{2} \]
      14. metadata-eval41.1%

        \[\leadsto \frac{2 + x \cdot \left(\left(-1 + \varepsilon\right) \cdot \left(1 + \frac{\color{blue}{-1}}{\varepsilon}\right)\right)}{2} \]
    9. Simplified41.1%

      \[\leadsto \frac{\color{blue}{2 + x \cdot \left(\left(-1 + \varepsilon\right) \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}}{2} \]
    10. Taylor expanded in eps around 0 63.5%

      \[\leadsto \frac{2 + \color{blue}{\frac{x + \varepsilon \cdot \left(-2 \cdot x + \varepsilon \cdot x\right)}{\varepsilon}}}{2} \]
    11. Step-by-step derivation
      1. distribute-rgt-out63.5%

        \[\leadsto \frac{2 + \frac{x + \varepsilon \cdot \color{blue}{\left(x \cdot \left(-2 + \varepsilon\right)\right)}}{\varepsilon}}{2} \]
    12. Simplified63.5%

      \[\leadsto \frac{2 + \color{blue}{\frac{x + \varepsilon \cdot \left(x \cdot \left(-2 + \varepsilon\right)\right)}{\varepsilon}}}{2} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification77.2%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\varepsilon \leq 46:\\ \;\;\;\;\frac{2 \cdot e^{-x}}{2}\\ \mathbf{elif}\;\varepsilon \leq 2.2 \cdot 10^{+115}:\\ \;\;\;\;\frac{1 + e^{x}}{2}\\ \mathbf{elif}\;\varepsilon \leq 6.6 \cdot 10^{+125}:\\ \;\;\;\;1 + x \cdot \left(x \cdot \left(0.25 + x \cdot -0.08333333333333333\right) - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{2 + \frac{x + \varepsilon \cdot \left(x \cdot \left(\varepsilon + -2\right)\right)}{\varepsilon}}{2}\\ \end{array} \]
  5. Add Preprocessing

Alternative 4: 66.6% accurate, 2.1× speedup?

\[\begin{array}{l} eps_m = \left|\varepsilon\right| \\ \begin{array}{l} \mathbf{if}\;x \leq -5 \cdot 10^{-82}:\\ \;\;\;\;1 + x \cdot \left(x \cdot \left(0.25 + x \cdot -0.08333333333333333\right) - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + e^{x}}{2}\\ \end{array} \end{array} \]
eps_m = (fabs.f64 eps)
(FPCore (x eps_m)
 :precision binary64
 (if (<= x -5e-82)
   (+ 1.0 (* x (- (* x (+ 0.25 (* x -0.08333333333333333))) 0.5)))
   (/ (+ 1.0 (exp x)) 2.0)))
eps_m = fabs(eps);
double code(double x, double eps_m) {
	double tmp;
	if (x <= -5e-82) {
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5));
	} else {
		tmp = (1.0 + exp(x)) / 2.0;
	}
	return tmp;
}
eps_m = abs(eps)
real(8) function code(x, eps_m)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps_m
    real(8) :: tmp
    if (x <= (-5d-82)) then
        tmp = 1.0d0 + (x * ((x * (0.25d0 + (x * (-0.08333333333333333d0)))) - 0.5d0))
    else
        tmp = (1.0d0 + exp(x)) / 2.0d0
    end if
    code = tmp
end function
eps_m = Math.abs(eps);
public static double code(double x, double eps_m) {
	double tmp;
	if (x <= -5e-82) {
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5));
	} else {
		tmp = (1.0 + Math.exp(x)) / 2.0;
	}
	return tmp;
}
eps_m = math.fabs(eps)
def code(x, eps_m):
	tmp = 0
	if x <= -5e-82:
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5))
	else:
		tmp = (1.0 + math.exp(x)) / 2.0
	return tmp
eps_m = abs(eps)
function code(x, eps_m)
	tmp = 0.0
	if (x <= -5e-82)
		tmp = Float64(1.0 + Float64(x * Float64(Float64(x * Float64(0.25 + Float64(x * -0.08333333333333333))) - 0.5)));
	else
		tmp = Float64(Float64(1.0 + exp(x)) / 2.0);
	end
	return tmp
end
eps_m = abs(eps);
function tmp_2 = code(x, eps_m)
	tmp = 0.0;
	if (x <= -5e-82)
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5));
	else
		tmp = (1.0 + exp(x)) / 2.0;
	end
	tmp_2 = tmp;
end
eps_m = N[Abs[eps], $MachinePrecision]
code[x_, eps$95$m_] := If[LessEqual[x, -5e-82], N[(1.0 + N[(x * N[(N[(x * N[(0.25 + N[(x * -0.08333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(1.0 + N[Exp[x], $MachinePrecision]), $MachinePrecision] / 2.0), $MachinePrecision]]
\begin{array}{l}
eps_m = \left|\varepsilon\right|

\\
\begin{array}{l}
\mathbf{if}\;x \leq -5 \cdot 10^{-82}:\\
\;\;\;\;1 + x \cdot \left(x \cdot \left(0.25 + x \cdot -0.08333333333333333\right) - 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{1 + e^{x}}{2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -4.9999999999999998e-82

    1. Initial program 73.7%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified72.0%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 98.7%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around inf 98.8%

      \[\leadsto \frac{e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    6. Step-by-step derivation
      1. associate-*r*98.8%

        \[\leadsto \frac{e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
      2. neg-mul-198.8%

        \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right)} \cdot x} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    7. Simplified98.8%

      \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    8. Taylor expanded in eps around 0 88.7%

      \[\leadsto \frac{\color{blue}{1 + e^{-1 \cdot x}}}{2} \]
    9. Step-by-step derivation
      1. neg-mul-188.7%

        \[\leadsto \frac{1 + e^{\color{blue}{-x}}}{2} \]
    10. Simplified88.7%

      \[\leadsto \frac{\color{blue}{1 + e^{-x}}}{2} \]
    11. Taylor expanded in x around 0 80.8%

      \[\leadsto \color{blue}{1 + x \cdot \left(x \cdot \left(0.25 + -0.08333333333333333 \cdot x\right) - 0.5\right)} \]

    if -4.9999999999999998e-82 < x

    1. Initial program 72.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified61.2%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 99.8%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around inf 84.4%

      \[\leadsto \frac{e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    6. Step-by-step derivation
      1. associate-*r*84.4%

        \[\leadsto \frac{e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
      2. neg-mul-184.4%

        \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right)} \cdot x} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    7. Simplified84.4%

      \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    8. Taylor expanded in eps around 0 45.0%

      \[\leadsto \frac{\color{blue}{1 + e^{-1 \cdot x}}}{2} \]
    9. Step-by-step derivation
      1. neg-mul-145.0%

        \[\leadsto \frac{1 + e^{\color{blue}{-x}}}{2} \]
    10. Simplified45.0%

      \[\leadsto \frac{\color{blue}{1 + e^{-x}}}{2} \]
    11. Step-by-step derivation
      1. frac-2neg45.0%

        \[\leadsto \color{blue}{\frac{-\left(1 + e^{-x}\right)}{-2}} \]
      2. distribute-frac-neg45.0%

        \[\leadsto \color{blue}{-\frac{1 + e^{-x}}{-2}} \]
      3. add-sqr-sqrt21.5%

        \[\leadsto -\frac{1 + e^{\color{blue}{\sqrt{-x} \cdot \sqrt{-x}}}}{-2} \]
      4. sqrt-unprod66.6%

        \[\leadsto -\frac{1 + e^{\color{blue}{\sqrt{\left(-x\right) \cdot \left(-x\right)}}}}{-2} \]
      5. sqr-neg66.6%

        \[\leadsto -\frac{1 + e^{\sqrt{\color{blue}{x \cdot x}}}}{-2} \]
      6. sqrt-unprod45.1%

        \[\leadsto -\frac{1 + e^{\color{blue}{\sqrt{x} \cdot \sqrt{x}}}}{-2} \]
      7. add-sqr-sqrt66.6%

        \[\leadsto -\frac{1 + e^{\color{blue}{x}}}{-2} \]
      8. metadata-eval66.6%

        \[\leadsto -\frac{1 + e^{x}}{\color{blue}{-2}} \]
    12. Applied egg-rr66.6%

      \[\leadsto \color{blue}{-\frac{1 + e^{x}}{-2}} \]
    13. Step-by-step derivation
      1. distribute-neg-frac266.6%

        \[\leadsto \color{blue}{\frac{1 + e^{x}}{--2}} \]
      2. metadata-eval66.6%

        \[\leadsto \frac{1 + e^{x}}{\color{blue}{2}} \]
    14. Simplified66.6%

      \[\leadsto \color{blue}{\frac{1 + e^{x}}{2}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification69.3%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -5 \cdot 10^{-82}:\\ \;\;\;\;1 + x \cdot \left(x \cdot \left(0.25 + x \cdot -0.08333333333333333\right) - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{1 + e^{x}}{2}\\ \end{array} \]
  5. Add Preprocessing

Alternative 5: 63.2% accurate, 11.9× speedup?

\[\begin{array}{l} eps_m = \left|\varepsilon\right| \\ \begin{array}{l} \mathbf{if}\;x \leq 4500 \lor \neg \left(x \leq 3.8 \cdot 10^{+146}\right):\\ \;\;\;\;1 + x \cdot \left(x \cdot 0.25 - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \end{array} \]
eps_m = (fabs.f64 eps)
(FPCore (x eps_m)
 :precision binary64
 (if (or (<= x 4500.0) (not (<= x 3.8e+146)))
   (+ 1.0 (* x (- (* x 0.25) 0.5)))
   0.0))
eps_m = fabs(eps);
double code(double x, double eps_m) {
	double tmp;
	if ((x <= 4500.0) || !(x <= 3.8e+146)) {
		tmp = 1.0 + (x * ((x * 0.25) - 0.5));
	} else {
		tmp = 0.0;
	}
	return tmp;
}
eps_m = abs(eps)
real(8) function code(x, eps_m)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps_m
    real(8) :: tmp
    if ((x <= 4500.0d0) .or. (.not. (x <= 3.8d+146))) then
        tmp = 1.0d0 + (x * ((x * 0.25d0) - 0.5d0))
    else
        tmp = 0.0d0
    end if
    code = tmp
end function
eps_m = Math.abs(eps);
public static double code(double x, double eps_m) {
	double tmp;
	if ((x <= 4500.0) || !(x <= 3.8e+146)) {
		tmp = 1.0 + (x * ((x * 0.25) - 0.5));
	} else {
		tmp = 0.0;
	}
	return tmp;
}
eps_m = math.fabs(eps)
def code(x, eps_m):
	tmp = 0
	if (x <= 4500.0) or not (x <= 3.8e+146):
		tmp = 1.0 + (x * ((x * 0.25) - 0.5))
	else:
		tmp = 0.0
	return tmp
eps_m = abs(eps)
function code(x, eps_m)
	tmp = 0.0
	if ((x <= 4500.0) || !(x <= 3.8e+146))
		tmp = Float64(1.0 + Float64(x * Float64(Float64(x * 0.25) - 0.5)));
	else
		tmp = 0.0;
	end
	return tmp
end
eps_m = abs(eps);
function tmp_2 = code(x, eps_m)
	tmp = 0.0;
	if ((x <= 4500.0) || ~((x <= 3.8e+146)))
		tmp = 1.0 + (x * ((x * 0.25) - 0.5));
	else
		tmp = 0.0;
	end
	tmp_2 = tmp;
end
eps_m = N[Abs[eps], $MachinePrecision]
code[x_, eps$95$m_] := If[Or[LessEqual[x, 4500.0], N[Not[LessEqual[x, 3.8e+146]], $MachinePrecision]], N[(1.0 + N[(x * N[(N[(x * 0.25), $MachinePrecision] - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 0.0]
\begin{array}{l}
eps_m = \left|\varepsilon\right|

\\
\begin{array}{l}
\mathbf{if}\;x \leq 4500 \lor \neg \left(x \leq 3.8 \cdot 10^{+146}\right):\\
\;\;\;\;1 + x \cdot \left(x \cdot 0.25 - 0.5\right)\\

\mathbf{else}:\\
\;\;\;\;0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 4500 or 3.79999999999999979e146 < x

    1. Initial program 66.6%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified55.6%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 99.5%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around inf 94.5%

      \[\leadsto \frac{e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    6. Step-by-step derivation
      1. associate-*r*94.5%

        \[\leadsto \frac{e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
      2. neg-mul-194.5%

        \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right)} \cdot x} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    7. Simplified94.5%

      \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    8. Taylor expanded in eps around 0 63.6%

      \[\leadsto \frac{\color{blue}{1 + e^{-1 \cdot x}}}{2} \]
    9. Step-by-step derivation
      1. neg-mul-163.6%

        \[\leadsto \frac{1 + e^{\color{blue}{-x}}}{2} \]
    10. Simplified63.6%

      \[\leadsto \frac{\color{blue}{1 + e^{-x}}}{2} \]
    11. Taylor expanded in x around 0 67.8%

      \[\leadsto \color{blue}{1 + x \cdot \left(0.25 \cdot x - 0.5\right)} \]

    if 4500 < x < 3.79999999999999979e146

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified100.0%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around 0 55.3%

      \[\leadsto \frac{\color{blue}{\frac{e^{-1 \cdot x} + -1 \cdot e^{-1 \cdot x}}{\varepsilon}}}{2} \]
    5. Taylor expanded in x around 0 55.3%

      \[\leadsto \color{blue}{0} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification65.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 4500 \lor \neg \left(x \leq 3.8 \cdot 10^{+146}\right):\\ \;\;\;\;1 + x \cdot \left(x \cdot 0.25 - 0.5\right)\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 65.4% accurate, 11.9× speedup?

\[\begin{array}{l} eps_m = \left|\varepsilon\right| \\ \begin{array}{l} \mathbf{if}\;x \leq 2.5:\\ \;\;\;\;1 + x \cdot \left(x \cdot \left(0.25 + x \cdot -0.08333333333333333\right) - 0.5\right)\\ \mathbf{elif}\;x \leq 3.8 \cdot 10^{+146}:\\ \;\;\;\;0\\ \mathbf{else}:\\ \;\;\;\;1 + x \cdot \left(x \cdot 0.25 - 0.5\right)\\ \end{array} \end{array} \]
eps_m = (fabs.f64 eps)
(FPCore (x eps_m)
 :precision binary64
 (if (<= x 2.5)
   (+ 1.0 (* x (- (* x (+ 0.25 (* x -0.08333333333333333))) 0.5)))
   (if (<= x 3.8e+146) 0.0 (+ 1.0 (* x (- (* x 0.25) 0.5))))))
eps_m = fabs(eps);
double code(double x, double eps_m) {
	double tmp;
	if (x <= 2.5) {
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5));
	} else if (x <= 3.8e+146) {
		tmp = 0.0;
	} else {
		tmp = 1.0 + (x * ((x * 0.25) - 0.5));
	}
	return tmp;
}
eps_m = abs(eps)
real(8) function code(x, eps_m)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps_m
    real(8) :: tmp
    if (x <= 2.5d0) then
        tmp = 1.0d0 + (x * ((x * (0.25d0 + (x * (-0.08333333333333333d0)))) - 0.5d0))
    else if (x <= 3.8d+146) then
        tmp = 0.0d0
    else
        tmp = 1.0d0 + (x * ((x * 0.25d0) - 0.5d0))
    end if
    code = tmp
end function
eps_m = Math.abs(eps);
public static double code(double x, double eps_m) {
	double tmp;
	if (x <= 2.5) {
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5));
	} else if (x <= 3.8e+146) {
		tmp = 0.0;
	} else {
		tmp = 1.0 + (x * ((x * 0.25) - 0.5));
	}
	return tmp;
}
eps_m = math.fabs(eps)
def code(x, eps_m):
	tmp = 0
	if x <= 2.5:
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5))
	elif x <= 3.8e+146:
		tmp = 0.0
	else:
		tmp = 1.0 + (x * ((x * 0.25) - 0.5))
	return tmp
eps_m = abs(eps)
function code(x, eps_m)
	tmp = 0.0
	if (x <= 2.5)
		tmp = Float64(1.0 + Float64(x * Float64(Float64(x * Float64(0.25 + Float64(x * -0.08333333333333333))) - 0.5)));
	elseif (x <= 3.8e+146)
		tmp = 0.0;
	else
		tmp = Float64(1.0 + Float64(x * Float64(Float64(x * 0.25) - 0.5)));
	end
	return tmp
end
eps_m = abs(eps);
function tmp_2 = code(x, eps_m)
	tmp = 0.0;
	if (x <= 2.5)
		tmp = 1.0 + (x * ((x * (0.25 + (x * -0.08333333333333333))) - 0.5));
	elseif (x <= 3.8e+146)
		tmp = 0.0;
	else
		tmp = 1.0 + (x * ((x * 0.25) - 0.5));
	end
	tmp_2 = tmp;
end
eps_m = N[Abs[eps], $MachinePrecision]
code[x_, eps$95$m_] := If[LessEqual[x, 2.5], N[(1.0 + N[(x * N[(N[(x * N[(0.25 + N[(x * -0.08333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[x, 3.8e+146], 0.0, N[(1.0 + N[(x * N[(N[(x * 0.25), $MachinePrecision] - 0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}
eps_m = \left|\varepsilon\right|

\\
\begin{array}{l}
\mathbf{if}\;x \leq 2.5:\\
\;\;\;\;1 + x \cdot \left(x \cdot \left(0.25 + x \cdot -0.08333333333333333\right) - 0.5\right)\\

\mathbf{elif}\;x \leq 3.8 \cdot 10^{+146}:\\
\;\;\;\;0\\

\mathbf{else}:\\
\;\;\;\;1 + x \cdot \left(x \cdot 0.25 - 0.5\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < 2.5

    1. Initial program 57.4%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified43.3%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 99.4%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around inf 99.4%

      \[\leadsto \frac{e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    6. Step-by-step derivation
      1. associate-*r*99.4%

        \[\leadsto \frac{e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
      2. neg-mul-199.4%

        \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right)} \cdot x} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    7. Simplified99.4%

      \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    8. Taylor expanded in eps around 0 80.4%

      \[\leadsto \frac{\color{blue}{1 + e^{-1 \cdot x}}}{2} \]
    9. Step-by-step derivation
      1. neg-mul-180.4%

        \[\leadsto \frac{1 + e^{\color{blue}{-x}}}{2} \]
    10. Simplified80.4%

      \[\leadsto \frac{\color{blue}{1 + e^{-x}}}{2} \]
    11. Taylor expanded in x around 0 78.1%

      \[\leadsto \color{blue}{1 + x \cdot \left(x \cdot \left(0.25 + -0.08333333333333333 \cdot x\right) - 0.5\right)} \]

    if 2.5 < x < 3.79999999999999979e146

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified100.0%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around 0 54.1%

      \[\leadsto \frac{\color{blue}{\frac{e^{-1 \cdot x} + -1 \cdot e^{-1 \cdot x}}{\varepsilon}}}{2} \]
    5. Taylor expanded in x around 0 54.1%

      \[\leadsto \color{blue}{0} \]

    if 3.79999999999999979e146 < x

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified100.0%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 100.0%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around inf 76.0%

      \[\leadsto \frac{e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    6. Step-by-step derivation
      1. associate-*r*76.0%

        \[\leadsto \frac{e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
      2. neg-mul-176.0%

        \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right)} \cdot x} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    7. Simplified76.0%

      \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    8. Taylor expanded in eps around 0 3.1%

      \[\leadsto \frac{\color{blue}{1 + e^{-1 \cdot x}}}{2} \]
    9. Step-by-step derivation
      1. neg-mul-13.1%

        \[\leadsto \frac{1 + e^{\color{blue}{-x}}}{2} \]
    10. Simplified3.1%

      \[\leadsto \frac{\color{blue}{1 + e^{-x}}}{2} \]
    11. Taylor expanded in x around 0 54.5%

      \[\leadsto \color{blue}{1 + x \cdot \left(0.25 \cdot x - 0.5\right)} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification69.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 2.5:\\ \;\;\;\;1 + x \cdot \left(x \cdot \left(0.25 + x \cdot -0.08333333333333333\right) - 0.5\right)\\ \mathbf{elif}\;x \leq 3.8 \cdot 10^{+146}:\\ \;\;\;\;0\\ \mathbf{else}:\\ \;\;\;\;1 + x \cdot \left(x \cdot 0.25 - 0.5\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 57.6% accurate, 37.7× speedup?

\[\begin{array}{l} eps_m = \left|\varepsilon\right| \\ \begin{array}{l} \mathbf{if}\;x \leq 4500:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;0\\ \end{array} \end{array} \]
eps_m = (fabs.f64 eps)
(FPCore (x eps_m) :precision binary64 (if (<= x 4500.0) 1.0 0.0))
eps_m = fabs(eps);
double code(double x, double eps_m) {
	double tmp;
	if (x <= 4500.0) {
		tmp = 1.0;
	} else {
		tmp = 0.0;
	}
	return tmp;
}
eps_m = abs(eps)
real(8) function code(x, eps_m)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps_m
    real(8) :: tmp
    if (x <= 4500.0d0) then
        tmp = 1.0d0
    else
        tmp = 0.0d0
    end if
    code = tmp
end function
eps_m = Math.abs(eps);
public static double code(double x, double eps_m) {
	double tmp;
	if (x <= 4500.0) {
		tmp = 1.0;
	} else {
		tmp = 0.0;
	}
	return tmp;
}
eps_m = math.fabs(eps)
def code(x, eps_m):
	tmp = 0
	if x <= 4500.0:
		tmp = 1.0
	else:
		tmp = 0.0
	return tmp
eps_m = abs(eps)
function code(x, eps_m)
	tmp = 0.0
	if (x <= 4500.0)
		tmp = 1.0;
	else
		tmp = 0.0;
	end
	return tmp
end
eps_m = abs(eps);
function tmp_2 = code(x, eps_m)
	tmp = 0.0;
	if (x <= 4500.0)
		tmp = 1.0;
	else
		tmp = 0.0;
	end
	tmp_2 = tmp;
end
eps_m = N[Abs[eps], $MachinePrecision]
code[x_, eps$95$m_] := If[LessEqual[x, 4500.0], 1.0, 0.0]
\begin{array}{l}
eps_m = \left|\varepsilon\right|

\\
\begin{array}{l}
\mathbf{if}\;x \leq 4500:\\
\;\;\;\;1\\

\mathbf{else}:\\
\;\;\;\;0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 4500

    1. Initial program 57.6%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified43.7%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around inf 99.4%

      \[\leadsto \frac{\color{blue}{e^{-1 \cdot \left(x \cdot \left(1 + \varepsilon\right)\right)} + e^{x \cdot \left(\varepsilon - 1\right)}}}{2} \]
    5. Taylor expanded in eps around inf 99.4%

      \[\leadsto \frac{e^{\color{blue}{-1 \cdot \left(\varepsilon \cdot x\right)}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    6. Step-by-step derivation
      1. associate-*r*99.4%

        \[\leadsto \frac{e^{\color{blue}{\left(-1 \cdot \varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
      2. neg-mul-199.4%

        \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right)} \cdot x} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    7. Simplified99.4%

      \[\leadsto \frac{e^{\color{blue}{\left(-\varepsilon\right) \cdot x}} + e^{x \cdot \left(\varepsilon - 1\right)}}{2} \]
    8. Taylor expanded in x around 0 63.9%

      \[\leadsto \frac{\color{blue}{2 + x \cdot \left(\left(\varepsilon + -1 \cdot \varepsilon\right) - 1\right)}}{2} \]
    9. Step-by-step derivation
      1. distribute-rgt1-in63.9%

        \[\leadsto \frac{2 + x \cdot \left(\color{blue}{\left(-1 + 1\right) \cdot \varepsilon} - 1\right)}{2} \]
      2. metadata-eval63.9%

        \[\leadsto \frac{2 + x \cdot \left(\color{blue}{0} \cdot \varepsilon - 1\right)}{2} \]
      3. mul0-lft63.9%

        \[\leadsto \frac{2 + x \cdot \left(\color{blue}{0} - 1\right)}{2} \]
      4. metadata-eval63.9%

        \[\leadsto \frac{2 + x \cdot \color{blue}{-1}}{2} \]
      5. *-commutative63.9%

        \[\leadsto \frac{2 + \color{blue}{-1 \cdot x}}{2} \]
      6. neg-mul-163.9%

        \[\leadsto \frac{2 + \color{blue}{\left(-x\right)}}{2} \]
      7. unsub-neg63.9%

        \[\leadsto \frac{\color{blue}{2 - x}}{2} \]
    10. Simplified63.9%

      \[\leadsto \frac{\color{blue}{2 - x}}{2} \]
    11. Taylor expanded in x around 0 64.1%

      \[\leadsto \color{blue}{1} \]

    if 4500 < x

    1. Initial program 100.0%

      \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
    2. Simplified100.0%

      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
    3. Add Preprocessing
    4. Taylor expanded in eps around 0 49.1%

      \[\leadsto \frac{\color{blue}{\frac{e^{-1 \cdot x} + -1 \cdot e^{-1 \cdot x}}{\varepsilon}}}{2} \]
    5. Taylor expanded in x around 0 49.1%

      \[\leadsto \color{blue}{0} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 8: 15.8% accurate, 227.0× speedup?

\[\begin{array}{l} eps_m = \left|\varepsilon\right| \\ 0 \end{array} \]
eps_m = (fabs.f64 eps)
(FPCore (x eps_m) :precision binary64 0.0)
eps_m = fabs(eps);
double code(double x, double eps_m) {
	return 0.0;
}
eps_m = abs(eps)
real(8) function code(x, eps_m)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps_m
    code = 0.0d0
end function
eps_m = Math.abs(eps);
public static double code(double x, double eps_m) {
	return 0.0;
}
eps_m = math.fabs(eps)
def code(x, eps_m):
	return 0.0
eps_m = abs(eps)
function code(x, eps_m)
	return 0.0
end
eps_m = abs(eps);
function tmp = code(x, eps_m)
	tmp = 0.0;
end
eps_m = N[Abs[eps], $MachinePrecision]
code[x_, eps$95$m_] := 0.0
\begin{array}{l}
eps_m = \left|\varepsilon\right|

\\
0
\end{array}
Derivation
  1. Initial program 72.4%

    \[\frac{\left(1 + \frac{1}{\varepsilon}\right) \cdot e^{-\left(1 - \varepsilon\right) \cdot x} - \left(\frac{1}{\varepsilon} - 1\right) \cdot e^{-\left(1 + \varepsilon\right) \cdot x}}{2} \]
  2. Simplified63.3%

    \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(1 + \frac{1}{\varepsilon}, e^{x \cdot \left(\varepsilon + -1\right)}, {\left(e^{1 + \varepsilon}\right)}^{\left(-x\right)} \cdot \left(1 + \frac{-1}{\varepsilon}\right)\right)}{2}} \]
  3. Add Preprocessing
  4. Taylor expanded in eps around 0 18.6%

    \[\leadsto \frac{\color{blue}{\frac{e^{-1 \cdot x} + -1 \cdot e^{-1 \cdot x}}{\varepsilon}}}{2} \]
  5. Taylor expanded in x around 0 18.7%

    \[\leadsto \color{blue}{0} \]
  6. Add Preprocessing

Reproduce

?
herbie shell --seed 2024155 
(FPCore (x eps)
  :name "NMSE Section 6.1 mentioned, A"
  :precision binary64
  (/ (- (* (+ 1.0 (/ 1.0 eps)) (exp (- (* (- 1.0 eps) x)))) (* (- (/ 1.0 eps) 1.0) (exp (- (* (+ 1.0 eps) x))))) 2.0))