Hyperbolic secant

Percentage Accurate: 100.0% → 100.0%
Time: 8.8s
Alternatives: 12
Speedup: 2.0×

Specification

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

\\
\frac{2}{e^{x} + e^{-x}}
\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 12 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: 100.0% accurate, 1.0× speedup?

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

\\
\frac{2}{e^{x} + e^{-x}}
\end{array}

Alternative 1: 100.0% accurate, 2.0× speedup?

\[\begin{array}{l} \\ \frac{1}{\cosh x} \end{array} \]
(FPCore (x) :precision binary64 (/ 1.0 (cosh x)))
double code(double x) {
	return 1.0 / cosh(x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 1.0d0 / cosh(x)
end function
public static double code(double x) {
	return 1.0 / Math.cosh(x);
}
def code(x):
	return 1.0 / math.cosh(x)
function code(x)
	return Float64(1.0 / cosh(x))
end
function tmp = code(x)
	tmp = 1.0 / cosh(x);
end
code[x_] := N[(1.0 / N[Cosh[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\cosh x}
\end{array}
Derivation
  1. Initial program 100.0%

    \[\frac{2}{e^{x} + e^{-x}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. rec-expN/A

      \[\leadsto \frac{2}{e^{x} + \frac{1}{\color{blue}{e^{x}}}} \]
    2. clear-numN/A

      \[\leadsto \frac{1}{\color{blue}{\frac{e^{x} + \frac{1}{e^{x}}}{2}}} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(\frac{e^{x} + \frac{1}{e^{x}}}{2}\right)}\right) \]
    4. rec-expN/A

      \[\leadsto \mathsf{/.f64}\left(1, \left(\frac{e^{x} + e^{\mathsf{neg}\left(x\right)}}{2}\right)\right) \]
    5. cosh-defN/A

      \[\leadsto \mathsf{/.f64}\left(1, \cosh x\right) \]
    6. cosh-lowering-cosh.f64100.0%

      \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
  4. Applied egg-rr100.0%

    \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
  5. Add Preprocessing

Alternative 2: 74.4% accurate, 2.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := x \cdot \left(x \cdot \left(x \cdot x\right)\right)\\ t_1 := \left(x \cdot x\right) \cdot t\_0\\ t_2 := x \cdot \left(x \cdot t\_1\right)\\ \mathbf{if}\;x \leq 3.4 \cdot 10^{+38}:\\ \;\;\;\;\frac{2}{\frac{\frac{256 - t\_0 \cdot \left(t\_1 \cdot t\_1\right)}{16 + t\_2}}{\left(t\_0 + 4\right) \cdot \left(2 - x \cdot x\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{16}{16 - t\_2}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (* x (* x (* x x)))) (t_1 (* (* x x) t_0)) (t_2 (* x (* x t_1))))
   (if (<= x 3.4e+38)
     (/
      2.0
      (/
       (/ (- 256.0 (* t_0 (* t_1 t_1))) (+ 16.0 t_2))
       (* (+ t_0 4.0) (- 2.0 (* x x)))))
     (/ 16.0 (- 16.0 t_2)))))
double code(double x) {
	double t_0 = x * (x * (x * x));
	double t_1 = (x * x) * t_0;
	double t_2 = x * (x * t_1);
	double tmp;
	if (x <= 3.4e+38) {
		tmp = 2.0 / (((256.0 - (t_0 * (t_1 * t_1))) / (16.0 + t_2)) / ((t_0 + 4.0) * (2.0 - (x * x))));
	} else {
		tmp = 16.0 / (16.0 - t_2);
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: t_2
    real(8) :: tmp
    t_0 = x * (x * (x * x))
    t_1 = (x * x) * t_0
    t_2 = x * (x * t_1)
    if (x <= 3.4d+38) then
        tmp = 2.0d0 / (((256.0d0 - (t_0 * (t_1 * t_1))) / (16.0d0 + t_2)) / ((t_0 + 4.0d0) * (2.0d0 - (x * x))))
    else
        tmp = 16.0d0 / (16.0d0 - t_2)
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = x * (x * (x * x));
	double t_1 = (x * x) * t_0;
	double t_2 = x * (x * t_1);
	double tmp;
	if (x <= 3.4e+38) {
		tmp = 2.0 / (((256.0 - (t_0 * (t_1 * t_1))) / (16.0 + t_2)) / ((t_0 + 4.0) * (2.0 - (x * x))));
	} else {
		tmp = 16.0 / (16.0 - t_2);
	}
	return tmp;
}
def code(x):
	t_0 = x * (x * (x * x))
	t_1 = (x * x) * t_0
	t_2 = x * (x * t_1)
	tmp = 0
	if x <= 3.4e+38:
		tmp = 2.0 / (((256.0 - (t_0 * (t_1 * t_1))) / (16.0 + t_2)) / ((t_0 + 4.0) * (2.0 - (x * x))))
	else:
		tmp = 16.0 / (16.0 - t_2)
	return tmp
function code(x)
	t_0 = Float64(x * Float64(x * Float64(x * x)))
	t_1 = Float64(Float64(x * x) * t_0)
	t_2 = Float64(x * Float64(x * t_1))
	tmp = 0.0
	if (x <= 3.4e+38)
		tmp = Float64(2.0 / Float64(Float64(Float64(256.0 - Float64(t_0 * Float64(t_1 * t_1))) / Float64(16.0 + t_2)) / Float64(Float64(t_0 + 4.0) * Float64(2.0 - Float64(x * x)))));
	else
		tmp = Float64(16.0 / Float64(16.0 - t_2));
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = x * (x * (x * x));
	t_1 = (x * x) * t_0;
	t_2 = x * (x * t_1);
	tmp = 0.0;
	if (x <= 3.4e+38)
		tmp = 2.0 / (((256.0 - (t_0 * (t_1 * t_1))) / (16.0 + t_2)) / ((t_0 + 4.0) * (2.0 - (x * x))));
	else
		tmp = 16.0 / (16.0 - t_2);
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(x * x), $MachinePrecision] * t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(x * N[(x * t$95$1), $MachinePrecision]), $MachinePrecision]}, If[LessEqual[x, 3.4e+38], N[(2.0 / N[(N[(N[(256.0 - N[(t$95$0 * N[(t$95$1 * t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(16.0 + t$95$2), $MachinePrecision]), $MachinePrecision] / N[(N[(t$95$0 + 4.0), $MachinePrecision] * N[(2.0 - N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(16.0 / N[(16.0 - t$95$2), $MachinePrecision]), $MachinePrecision]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := x \cdot \left(x \cdot \left(x \cdot x\right)\right)\\
t_1 := \left(x \cdot x\right) \cdot t\_0\\
t_2 := x \cdot \left(x \cdot t\_1\right)\\
\mathbf{if}\;x \leq 3.4 \cdot 10^{+38}:\\
\;\;\;\;\frac{2}{\frac{\frac{256 - t\_0 \cdot \left(t\_1 \cdot t\_1\right)}{16 + t\_2}}{\left(t\_0 + 4\right) \cdot \left(2 - x \cdot x\right)}}\\

\mathbf{else}:\\
\;\;\;\;\frac{16}{16 - t\_2}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 3.39999999999999996e38

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
    4. Step-by-step derivation
      1. +-lowering-+.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
      3. *-lowering-*.f6480.5%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
    5. Simplified80.5%

      \[\leadsto \frac{2}{\color{blue}{2 + x \cdot x}} \]
    6. Step-by-step derivation
      1. flip-+N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{2 \cdot 2 - \left(x \cdot x\right) \cdot \left(x \cdot x\right)}{\color{blue}{2 - x \cdot x}}\right)\right) \]
      2. div-invN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(2 \cdot 2 - \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \color{blue}{\frac{1}{2 - x \cdot x}}\right)\right) \]
      3. flip--N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)}{2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)} \cdot \frac{\color{blue}{1}}{2 - x \cdot x}\right)\right) \]
      4. frac-timesN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right) \cdot 1}{\color{blue}{\left(2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(2 - x \cdot x\right)}}\right)\right) \]
      5. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{/.f64}\left(\left(\left(\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right) \cdot 1\right), \color{blue}{\left(\left(2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(2 - x \cdot x\right)\right)}\right)\right) \]
    7. Applied egg-rr63.1%

      \[\leadsto \frac{2}{\color{blue}{\frac{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1}{\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)}}} \]
    8. Step-by-step derivation
      1. *-rgt-identityN/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{/.f64}\left(\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right), \mathsf{*.f64}\left(\color{blue}{\mathsf{+.f64}\left(4, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)}, \mathsf{\_.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      2. flip--N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{/.f64}\left(\left(\frac{16 \cdot 16 - \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}{16 + \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)}\right), \mathsf{*.f64}\left(\color{blue}{\mathsf{+.f64}\left(4, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)}, \mathsf{\_.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
      3. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{/.f64}\left(\mathsf{/.f64}\left(\left(16 \cdot 16 - \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)\right), \left(16 + \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)\right), \mathsf{*.f64}\left(\color{blue}{\mathsf{+.f64}\left(4, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)}, \mathsf{\_.f64}\left(2, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right) \]
    9. Applied egg-rr65.0%

      \[\leadsto \frac{2}{\frac{\color{blue}{\frac{256 - \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}{16 + x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}}}{\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)}} \]

    if 3.39999999999999996e38 < x

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Taylor expanded in x around 0

      \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
    4. Step-by-step derivation
      1. +-lowering-+.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
      2. unpow2N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
      3. *-lowering-*.f6464.0%

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
    5. Simplified64.0%

      \[\leadsto \frac{2}{\color{blue}{2 + x \cdot x}} \]
    6. Step-by-step derivation
      1. flip-+N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{2 \cdot 2 - \left(x \cdot x\right) \cdot \left(x \cdot x\right)}{\color{blue}{2 - x \cdot x}}\right)\right) \]
      2. div-invN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\left(2 \cdot 2 - \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \color{blue}{\frac{1}{2 - x \cdot x}}\right)\right) \]
      3. flip--N/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)}{2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)} \cdot \frac{\color{blue}{1}}{2 - x \cdot x}\right)\right) \]
      4. frac-timesN/A

        \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right) \cdot 1}{\color{blue}{\left(2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(2 - x \cdot x\right)}}\right)\right) \]
      5. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{/.f64}\left(\left(\left(\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right) \cdot 1\right), \color{blue}{\left(\left(2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(2 - x \cdot x\right)\right)}\right)\right) \]
    7. Applied egg-rr7.9%

      \[\leadsto \frac{2}{\color{blue}{\frac{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1}{\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)}}} \]
    8. Step-by-step derivation
      1. associate-/r/N/A

        \[\leadsto \frac{2}{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1} \cdot \color{blue}{\left(\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)\right)} \]
      2. associate-*l/N/A

        \[\leadsto \frac{2 \cdot \left(\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)\right)}{\color{blue}{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1}} \]
      3. /-lowering-/.f64N/A

        \[\leadsto \mathsf{/.f64}\left(\left(2 \cdot \left(\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)\right)\right), \color{blue}{\left(\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1\right)}\right) \]
    9. Applied egg-rr7.9%

      \[\leadsto \color{blue}{\frac{2 \cdot \left(\left(x \cdot \left(x \cdot \left(x \cdot x\right)\right) + 4\right) \cdot \left(2 - x \cdot x\right)\right)}{16 - x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}} \]
    10. Taylor expanded in x around 0

      \[\leadsto \mathsf{/.f64}\left(\color{blue}{16}, \mathsf{\_.f64}\left(16, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right)\right)\right)\right) \]
    11. Step-by-step derivation
      1. Simplified100.0%

        \[\leadsto \frac{\color{blue}{16}}{16 - x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)} \]
    12. Recombined 2 regimes into one program.
    13. Final simplification73.6%

      \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 3.4 \cdot 10^{+38}:\\ \;\;\;\;\frac{2}{\frac{\frac{256 - \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}{16 + x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}}{\left(x \cdot \left(x \cdot \left(x \cdot x\right)\right) + 4\right) \cdot \left(2 - x \cdot x\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{16}{16 - x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}\\ \end{array} \]
    14. Add Preprocessing

    Alternative 3: 73.1% accurate, 3.6× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := x \cdot \left(x \cdot \left(x \cdot x\right)\right)\\ t_1 := \left(x \cdot x\right) \cdot t\_0\\ \mathbf{if}\;x \leq 5 \cdot 10^{+38}:\\ \;\;\;\;\frac{2}{\frac{8 + \frac{t\_1 \cdot t\_1}{1728}}{4 + \frac{\frac{x \cdot x}{\frac{12}{x \cdot x}} - 2}{\frac{12}{t\_0}}}}\\ \mathbf{else}:\\ \;\;\;\;\frac{16}{16 - x \cdot \left(x \cdot t\_1\right)}\\ \end{array} \end{array} \]
    (FPCore (x)
     :precision binary64
     (let* ((t_0 (* x (* x (* x x)))) (t_1 (* (* x x) t_0)))
       (if (<= x 5e+38)
         (/
          2.0
          (/
           (+ 8.0 (/ (* t_1 t_1) 1728.0))
           (+ 4.0 (/ (- (/ (* x x) (/ 12.0 (* x x))) 2.0) (/ 12.0 t_0)))))
         (/ 16.0 (- 16.0 (* x (* x t_1)))))))
    double code(double x) {
    	double t_0 = x * (x * (x * x));
    	double t_1 = (x * x) * t_0;
    	double tmp;
    	if (x <= 5e+38) {
    		tmp = 2.0 / ((8.0 + ((t_1 * t_1) / 1728.0)) / (4.0 + ((((x * x) / (12.0 / (x * x))) - 2.0) / (12.0 / t_0))));
    	} else {
    		tmp = 16.0 / (16.0 - (x * (x * t_1)));
    	}
    	return tmp;
    }
    
    real(8) function code(x)
        real(8), intent (in) :: x
        real(8) :: t_0
        real(8) :: t_1
        real(8) :: tmp
        t_0 = x * (x * (x * x))
        t_1 = (x * x) * t_0
        if (x <= 5d+38) then
            tmp = 2.0d0 / ((8.0d0 + ((t_1 * t_1) / 1728.0d0)) / (4.0d0 + ((((x * x) / (12.0d0 / (x * x))) - 2.0d0) / (12.0d0 / t_0))))
        else
            tmp = 16.0d0 / (16.0d0 - (x * (x * t_1)))
        end if
        code = tmp
    end function
    
    public static double code(double x) {
    	double t_0 = x * (x * (x * x));
    	double t_1 = (x * x) * t_0;
    	double tmp;
    	if (x <= 5e+38) {
    		tmp = 2.0 / ((8.0 + ((t_1 * t_1) / 1728.0)) / (4.0 + ((((x * x) / (12.0 / (x * x))) - 2.0) / (12.0 / t_0))));
    	} else {
    		tmp = 16.0 / (16.0 - (x * (x * t_1)));
    	}
    	return tmp;
    }
    
    def code(x):
    	t_0 = x * (x * (x * x))
    	t_1 = (x * x) * t_0
    	tmp = 0
    	if x <= 5e+38:
    		tmp = 2.0 / ((8.0 + ((t_1 * t_1) / 1728.0)) / (4.0 + ((((x * x) / (12.0 / (x * x))) - 2.0) / (12.0 / t_0))))
    	else:
    		tmp = 16.0 / (16.0 - (x * (x * t_1)))
    	return tmp
    
    function code(x)
    	t_0 = Float64(x * Float64(x * Float64(x * x)))
    	t_1 = Float64(Float64(x * x) * t_0)
    	tmp = 0.0
    	if (x <= 5e+38)
    		tmp = Float64(2.0 / Float64(Float64(8.0 + Float64(Float64(t_1 * t_1) / 1728.0)) / Float64(4.0 + Float64(Float64(Float64(Float64(x * x) / Float64(12.0 / Float64(x * x))) - 2.0) / Float64(12.0 / t_0)))));
    	else
    		tmp = Float64(16.0 / Float64(16.0 - Float64(x * Float64(x * t_1))));
    	end
    	return tmp
    end
    
    function tmp_2 = code(x)
    	t_0 = x * (x * (x * x));
    	t_1 = (x * x) * t_0;
    	tmp = 0.0;
    	if (x <= 5e+38)
    		tmp = 2.0 / ((8.0 + ((t_1 * t_1) / 1728.0)) / (4.0 + ((((x * x) / (12.0 / (x * x))) - 2.0) / (12.0 / t_0))));
    	else
    		tmp = 16.0 / (16.0 - (x * (x * t_1)));
    	end
    	tmp_2 = tmp;
    end
    
    code[x_] := Block[{t$95$0 = N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(x * x), $MachinePrecision] * t$95$0), $MachinePrecision]}, If[LessEqual[x, 5e+38], N[(2.0 / N[(N[(8.0 + N[(N[(t$95$1 * t$95$1), $MachinePrecision] / 1728.0), $MachinePrecision]), $MachinePrecision] / N[(4.0 + N[(N[(N[(N[(x * x), $MachinePrecision] / N[(12.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - 2.0), $MachinePrecision] / N[(12.0 / t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(16.0 / N[(16.0 - N[(x * N[(x * t$95$1), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := x \cdot \left(x \cdot \left(x \cdot x\right)\right)\\
    t_1 := \left(x \cdot x\right) \cdot t\_0\\
    \mathbf{if}\;x \leq 5 \cdot 10^{+38}:\\
    \;\;\;\;\frac{2}{\frac{8 + \frac{t\_1 \cdot t\_1}{1728}}{4 + \frac{\frac{x \cdot x}{\frac{12}{x \cdot x}} - 2}{\frac{12}{t\_0}}}}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{16}{16 - x \cdot \left(x \cdot t\_1\right)}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if x < 4.9999999999999997e38

      1. Initial program 100.0%

        \[\frac{2}{e^{x} + e^{-x}} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
      4. Step-by-step derivation
        1. +-lowering-+.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right)\right) \]
        2. *-lowering-*.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right) \]
        3. unpow2N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
        4. *-lowering-*.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
        5. +-lowering-+.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right)\right) \]
        6. *-commutativeN/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \left({x}^{2} \cdot \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
        7. *-lowering-*.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
        8. unpow2N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
        9. *-lowering-*.f6491.3%

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
      5. Simplified91.3%

        \[\leadsto \frac{2}{\color{blue}{2 + \left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)}} \]
      6. Step-by-step derivation
        1. flip3-+N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(\left(x \cdot x\right) \cdot \frac{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}{\color{blue}{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}}\right)\right)\right) \]
        2. clear-numN/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(\left(x \cdot x\right) \cdot \frac{1}{\color{blue}{\frac{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}}}\right)\right)\right) \]
        3. un-div-invN/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(\frac{x \cdot x}{\color{blue}{\frac{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}}}\right)\right)\right) \]
        4. /-lowering-/.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\left(x \cdot x\right), \color{blue}{\left(\frac{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}\right)}\right)\right)\right) \]
        5. *-lowering-*.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{\color{blue}{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}}{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}\right)\right)\right)\right) \]
        6. clear-numN/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{\color{blue}{\frac{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}}}\right)\right)\right)\right) \]
        7. flip3-+N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{1 + \color{blue}{\left(x \cdot x\right) \cdot \frac{1}{12}}}\right)\right)\right)\right) \]
        8. /-lowering-/.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(1, \color{blue}{\left(1 + \left(x \cdot x\right) \cdot \frac{1}{12}\right)}\right)\right)\right)\right) \]
        9. +-lowering-+.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \color{blue}{\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}\right)\right)\right)\right)\right) \]
        10. *-lowering-*.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right)\right) \]
        11. *-lowering-*.f6491.3%

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right)\right)\right) \]
      7. Applied egg-rr91.3%

        \[\leadsto \frac{2}{2 + \color{blue}{\frac{x \cdot x}{\frac{1}{1 + \left(x \cdot x\right) \cdot 0.08333333333333333}}}} \]
      8. Taylor expanded in x around inf

        \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \color{blue}{\left(\frac{12}{{x}^{2}}\right)}\right)\right)\right) \]
      9. Step-by-step derivation
        1. /-lowering-/.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(12, \color{blue}{\left({x}^{2}\right)}\right)\right)\right)\right) \]
        2. unpow2N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(12, \left(x \cdot \color{blue}{x}\right)\right)\right)\right)\right) \]
        3. *-lowering-*.f6491.0%

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(12, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right)\right)\right) \]
      10. Simplified91.0%

        \[\leadsto \frac{2}{2 + \frac{x \cdot x}{\color{blue}{\frac{12}{x \cdot x}}}} \]
      11. Step-by-step derivation
        1. flip3-+N/A

          \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{{2}^{3} + {\left(\frac{x \cdot x}{\frac{12}{x \cdot x}}\right)}^{3}}{\color{blue}{2 \cdot 2 + \left(\frac{x \cdot x}{\frac{12}{x \cdot x}} \cdot \frac{x \cdot x}{\frac{12}{x \cdot x}} - 2 \cdot \frac{x \cdot x}{\frac{12}{x \cdot x}}\right)}}\right)\right) \]
        2. /-lowering-/.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{/.f64}\left(\left({2}^{3} + {\left(\frac{x \cdot x}{\frac{12}{x \cdot x}}\right)}^{3}\right), \color{blue}{\left(2 \cdot 2 + \left(\frac{x \cdot x}{\frac{12}{x \cdot x}} \cdot \frac{x \cdot x}{\frac{12}{x \cdot x}} - 2 \cdot \frac{x \cdot x}{\frac{12}{x \cdot x}}\right)\right)}\right)\right) \]
      12. Applied egg-rr64.3%

        \[\leadsto \frac{2}{\color{blue}{\frac{8 + \frac{\left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)}{1728}}{4 + \frac{\frac{x \cdot x}{\frac{12}{x \cdot x}} - 2}{\frac{12}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}}}}} \]

      if 4.9999999999999997e38 < x

      1. Initial program 100.0%

        \[\frac{2}{e^{x} + e^{-x}} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
      4. Step-by-step derivation
        1. +-lowering-+.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
        2. unpow2N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
        3. *-lowering-*.f6464.0%

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
      5. Simplified64.0%

        \[\leadsto \frac{2}{\color{blue}{2 + x \cdot x}} \]
      6. Step-by-step derivation
        1. flip-+N/A

          \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{2 \cdot 2 - \left(x \cdot x\right) \cdot \left(x \cdot x\right)}{\color{blue}{2 - x \cdot x}}\right)\right) \]
        2. div-invN/A

          \[\leadsto \mathsf{/.f64}\left(2, \left(\left(2 \cdot 2 - \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \color{blue}{\frac{1}{2 - x \cdot x}}\right)\right) \]
        3. flip--N/A

          \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)}{2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)} \cdot \frac{\color{blue}{1}}{2 - x \cdot x}\right)\right) \]
        4. frac-timesN/A

          \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right) \cdot 1}{\color{blue}{\left(2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(2 - x \cdot x\right)}}\right)\right) \]
        5. /-lowering-/.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{/.f64}\left(\left(\left(\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right) \cdot 1\right), \color{blue}{\left(\left(2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(2 - x \cdot x\right)\right)}\right)\right) \]
      7. Applied egg-rr7.9%

        \[\leadsto \frac{2}{\color{blue}{\frac{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1}{\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)}}} \]
      8. Step-by-step derivation
        1. associate-/r/N/A

          \[\leadsto \frac{2}{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1} \cdot \color{blue}{\left(\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)\right)} \]
        2. associate-*l/N/A

          \[\leadsto \frac{2 \cdot \left(\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)\right)}{\color{blue}{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1}} \]
        3. /-lowering-/.f64N/A

          \[\leadsto \mathsf{/.f64}\left(\left(2 \cdot \left(\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)\right)\right), \color{blue}{\left(\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1\right)}\right) \]
      9. Applied egg-rr7.9%

        \[\leadsto \color{blue}{\frac{2 \cdot \left(\left(x \cdot \left(x \cdot \left(x \cdot x\right)\right) + 4\right) \cdot \left(2 - x \cdot x\right)\right)}{16 - x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}} \]
      10. Taylor expanded in x around 0

        \[\leadsto \mathsf{/.f64}\left(\color{blue}{16}, \mathsf{\_.f64}\left(16, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right)\right)\right)\right) \]
      11. Step-by-step derivation
        1. Simplified100.0%

          \[\leadsto \frac{\color{blue}{16}}{16 - x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)} \]
      12. Recombined 2 regimes into one program.
      13. Add Preprocessing

      Alternative 4: 93.0% accurate, 10.8× speedup?

      \[\begin{array}{l} \\ \frac{16}{16 - x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)} \end{array} \]
      (FPCore (x)
       :precision binary64
       (/ 16.0 (- 16.0 (* x (* x (* (* x x) (* x (* x (* x x)))))))))
      double code(double x) {
      	return 16.0 / (16.0 - (x * (x * ((x * x) * (x * (x * (x * x)))))));
      }
      
      real(8) function code(x)
          real(8), intent (in) :: x
          code = 16.0d0 / (16.0d0 - (x * (x * ((x * x) * (x * (x * (x * x)))))))
      end function
      
      public static double code(double x) {
      	return 16.0 / (16.0 - (x * (x * ((x * x) * (x * (x * (x * x)))))));
      }
      
      def code(x):
      	return 16.0 / (16.0 - (x * (x * ((x * x) * (x * (x * (x * x)))))))
      
      function code(x)
      	return Float64(16.0 / Float64(16.0 - Float64(x * Float64(x * Float64(Float64(x * x) * Float64(x * Float64(x * Float64(x * x))))))))
      end
      
      function tmp = code(x)
      	tmp = 16.0 / (16.0 - (x * (x * ((x * x) * (x * (x * (x * x)))))));
      end
      
      code[x_] := N[(16.0 / N[(16.0 - N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{16}{16 - x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}
      \end{array}
      
      Derivation
      1. Initial program 100.0%

        \[\frac{2}{e^{x} + e^{-x}} \]
      2. Add Preprocessing
      3. Taylor expanded in x around 0

        \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
      4. Step-by-step derivation
        1. +-lowering-+.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
        2. unpow2N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
        3. *-lowering-*.f6476.5%

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
      5. Simplified76.5%

        \[\leadsto \frac{2}{\color{blue}{2 + x \cdot x}} \]
      6. Step-by-step derivation
        1. flip-+N/A

          \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{2 \cdot 2 - \left(x \cdot x\right) \cdot \left(x \cdot x\right)}{\color{blue}{2 - x \cdot x}}\right)\right) \]
        2. div-invN/A

          \[\leadsto \mathsf{/.f64}\left(2, \left(\left(2 \cdot 2 - \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \color{blue}{\frac{1}{2 - x \cdot x}}\right)\right) \]
        3. flip--N/A

          \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)}{2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)} \cdot \frac{\color{blue}{1}}{2 - x \cdot x}\right)\right) \]
        4. frac-timesN/A

          \[\leadsto \mathsf{/.f64}\left(2, \left(\frac{\left(\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right) \cdot 1}{\color{blue}{\left(2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(2 - x \cdot x\right)}}\right)\right) \]
        5. /-lowering-/.f64N/A

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{/.f64}\left(\left(\left(\left(2 \cdot 2\right) \cdot \left(2 \cdot 2\right) - \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right) \cdot 1\right), \color{blue}{\left(\left(2 \cdot 2 + \left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(2 - x \cdot x\right)\right)}\right)\right) \]
      7. Applied egg-rr49.5%

        \[\leadsto \frac{2}{\color{blue}{\frac{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1}{\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)}}} \]
      8. Step-by-step derivation
        1. associate-/r/N/A

          \[\leadsto \frac{2}{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1} \cdot \color{blue}{\left(\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)\right)} \]
        2. associate-*l/N/A

          \[\leadsto \frac{2 \cdot \left(\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)\right)}{\color{blue}{\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1}} \]
        3. /-lowering-/.f64N/A

          \[\leadsto \mathsf{/.f64}\left(\left(2 \cdot \left(\left(4 + x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right) \cdot \left(2 - x \cdot x\right)\right)\right), \color{blue}{\left(\left(16 - \left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right) \cdot 1\right)}\right) \]
      9. Applied egg-rr49.5%

        \[\leadsto \color{blue}{\frac{2 \cdot \left(\left(x \cdot \left(x \cdot \left(x \cdot x\right)\right) + 4\right) \cdot \left(2 - x \cdot x\right)\right)}{16 - x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)}} \]
      10. Taylor expanded in x around 0

        \[\leadsto \mathsf{/.f64}\left(\color{blue}{16}, \mathsf{\_.f64}\left(16, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, x\right)\right)\right)\right)\right)\right)\right)\right) \]
      11. Step-by-step derivation
        1. Simplified95.1%

          \[\leadsto \frac{\color{blue}{16}}{16 - x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot \left(x \cdot \left(x \cdot x\right)\right)\right)\right)\right)} \]
        2. Add Preprocessing

        Alternative 5: 91.3% accurate, 10.8× speedup?

        \[\begin{array}{l} \\ \frac{1}{1 + \left(x \cdot x\right) \cdot \left(0.5 + x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot 0.001388888888888889\right)\right)\right)} \end{array} \]
        (FPCore (x)
         :precision binary64
         (/
          1.0
          (+ 1.0 (* (* x x) (+ 0.5 (* x (* x (* (* x x) 0.001388888888888889))))))))
        double code(double x) {
        	return 1.0 / (1.0 + ((x * x) * (0.5 + (x * (x * ((x * x) * 0.001388888888888889))))));
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            code = 1.0d0 / (1.0d0 + ((x * x) * (0.5d0 + (x * (x * ((x * x) * 0.001388888888888889d0))))))
        end function
        
        public static double code(double x) {
        	return 1.0 / (1.0 + ((x * x) * (0.5 + (x * (x * ((x * x) * 0.001388888888888889))))));
        }
        
        def code(x):
        	return 1.0 / (1.0 + ((x * x) * (0.5 + (x * (x * ((x * x) * 0.001388888888888889))))))
        
        function code(x)
        	return Float64(1.0 / Float64(1.0 + Float64(Float64(x * x) * Float64(0.5 + Float64(x * Float64(x * Float64(Float64(x * x) * 0.001388888888888889)))))))
        end
        
        function tmp = code(x)
        	tmp = 1.0 / (1.0 + ((x * x) * (0.5 + (x * (x * ((x * x) * 0.001388888888888889))))));
        end
        
        code[x_] := N[(1.0 / N[(1.0 + N[(N[(x * x), $MachinePrecision] * N[(0.5 + N[(x * N[(x * N[(N[(x * x), $MachinePrecision] * 0.001388888888888889), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \frac{1}{1 + \left(x \cdot x\right) \cdot \left(0.5 + x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot 0.001388888888888889\right)\right)\right)}
        \end{array}
        
        Derivation
        1. Initial program 100.0%

          \[\frac{2}{e^{x} + e^{-x}} \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. rec-expN/A

            \[\leadsto \frac{2}{e^{x} + \frac{1}{\color{blue}{e^{x}}}} \]
          2. clear-numN/A

            \[\leadsto \frac{1}{\color{blue}{\frac{e^{x} + \frac{1}{e^{x}}}{2}}} \]
          3. /-lowering-/.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(\frac{e^{x} + \frac{1}{e^{x}}}{2}\right)}\right) \]
          4. rec-expN/A

            \[\leadsto \mathsf{/.f64}\left(1, \left(\frac{e^{x} + e^{\mathsf{neg}\left(x\right)}}{2}\right)\right) \]
          5. cosh-defN/A

            \[\leadsto \mathsf{/.f64}\left(1, \cosh x\right) \]
          6. cosh-lowering-cosh.f64100.0%

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{cosh.f64}\left(x\right)\right) \]
        4. Applied egg-rr100.0%

          \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
        5. Taylor expanded in x around 0

          \[\leadsto \mathsf{/.f64}\left(1, \color{blue}{\left(1 + {x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)}\right) \]
        6. Step-by-step derivation
          1. +-lowering-+.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)}\right)\right) \]
          2. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}\right)\right)\right) \]
          3. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
          4. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{2}} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)\right)\right) \]
          5. +-lowering-+.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \color{blue}{\left({x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right)}\right)\right)\right)\right) \]
          6. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right) \]
          7. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{\frac{1}{24}} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)\right)\right)\right) \]
          8. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{\frac{1}{24}} + \frac{1}{720} \cdot {x}^{2}\right)\right)\right)\right)\right)\right) \]
          9. +-lowering-+.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{24}, \color{blue}{\left(\frac{1}{720} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right)\right) \]
          10. *-commutativeN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{24}, \left({x}^{2} \cdot \color{blue}{\frac{1}{720}}\right)\right)\right)\right)\right)\right)\right) \]
          11. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{24}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{720}}\right)\right)\right)\right)\right)\right)\right) \]
          12. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{24}, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{720}\right)\right)\right)\right)\right)\right)\right) \]
          13. *-lowering-*.f6492.8%

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{24}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{720}\right)\right)\right)\right)\right)\right)\right) \]
        7. Simplified92.8%

          \[\leadsto \frac{1}{\color{blue}{1 + \left(x \cdot x\right) \cdot \left(0.5 + \left(x \cdot x\right) \cdot \left(0.041666666666666664 + \left(x \cdot x\right) \cdot 0.001388888888888889\right)\right)}} \]
        8. Taylor expanded in x around inf

          \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \color{blue}{\left(\frac{1}{720} \cdot {x}^{4}\right)}\right)\right)\right)\right) \]
        9. Step-by-step derivation
          1. metadata-evalN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \left(\frac{1}{720} \cdot {x}^{\left(2 \cdot \color{blue}{2}\right)}\right)\right)\right)\right)\right) \]
          2. pow-sqrN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \left(\frac{1}{720} \cdot \left({x}^{2} \cdot \color{blue}{{x}^{2}}\right)\right)\right)\right)\right)\right) \]
          3. associate-*l*N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \left(\left(\frac{1}{720} \cdot {x}^{2}\right) \cdot \color{blue}{{x}^{2}}\right)\right)\right)\right)\right) \]
          4. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \left(\left(\frac{1}{720} \cdot {x}^{2}\right) \cdot \left(x \cdot \color{blue}{x}\right)\right)\right)\right)\right)\right) \]
          5. associate-*r*N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \left(\left(\left(\frac{1}{720} \cdot {x}^{2}\right) \cdot x\right) \cdot \color{blue}{x}\right)\right)\right)\right)\right) \]
          6. *-commutativeN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \left(x \cdot \color{blue}{\left(\left(\frac{1}{720} \cdot {x}^{2}\right) \cdot x\right)}\right)\right)\right)\right)\right) \]
          7. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(x, \color{blue}{\left(\left(\frac{1}{720} \cdot {x}^{2}\right) \cdot x\right)}\right)\right)\right)\right)\right) \]
          8. *-commutativeN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{\left(\frac{1}{720} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right)\right) \]
          9. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{1}{720} \cdot {x}^{2}\right)}\right)\right)\right)\right)\right)\right) \]
          10. *-commutativeN/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left({x}^{2} \cdot \color{blue}{\frac{1}{720}}\right)\right)\right)\right)\right)\right)\right) \]
          11. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{720}}\right)\right)\right)\right)\right)\right)\right) \]
          12. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{720}\right)\right)\right)\right)\right)\right)\right) \]
          13. *-lowering-*.f6492.7%

            \[\leadsto \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(\frac{1}{2}, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{720}\right)\right)\right)\right)\right)\right)\right) \]
        10. Simplified92.7%

          \[\leadsto \frac{1}{1 + \left(x \cdot x\right) \cdot \left(0.5 + \color{blue}{x \cdot \left(x \cdot \left(\left(x \cdot x\right) \cdot 0.001388888888888889\right)\right)}\right)} \]
        11. Add Preprocessing

        Alternative 6: 68.9% accurate, 11.4× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.9:\\ \;\;\;\;1 + x \cdot \left(x \cdot \left(-0.5 + \left(x \cdot x\right) \cdot 0.20833333333333334\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x 1.9)
           (+ 1.0 (* x (* x (+ -0.5 (* (* x x) 0.20833333333333334)))))
           (/ 24.0 (* x (* x (* x x))))))
        double code(double x) {
        	double tmp;
        	if (x <= 1.9) {
        		tmp = 1.0 + (x * (x * (-0.5 + ((x * x) * 0.20833333333333334))));
        	} else {
        		tmp = 24.0 / (x * (x * (x * x)));
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if (x <= 1.9d0) then
                tmp = 1.0d0 + (x * (x * ((-0.5d0) + ((x * x) * 0.20833333333333334d0))))
            else
                tmp = 24.0d0 / (x * (x * (x * x)))
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if (x <= 1.9) {
        		tmp = 1.0 + (x * (x * (-0.5 + ((x * x) * 0.20833333333333334))));
        	} else {
        		tmp = 24.0 / (x * (x * (x * x)));
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if x <= 1.9:
        		tmp = 1.0 + (x * (x * (-0.5 + ((x * x) * 0.20833333333333334))))
        	else:
        		tmp = 24.0 / (x * (x * (x * x)))
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if (x <= 1.9)
        		tmp = Float64(1.0 + Float64(x * Float64(x * Float64(-0.5 + Float64(Float64(x * x) * 0.20833333333333334)))));
        	else
        		tmp = Float64(24.0 / Float64(x * Float64(x * Float64(x * x))));
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if (x <= 1.9)
        		tmp = 1.0 + (x * (x * (-0.5 + ((x * x) * 0.20833333333333334))));
        	else
        		tmp = 24.0 / (x * (x * (x * x)));
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[LessEqual[x, 1.9], N[(1.0 + N[(x * N[(x * N[(-0.5 + N[(N[(x * x), $MachinePrecision] * 0.20833333333333334), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(24.0 / N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq 1.9:\\
        \;\;\;\;1 + x \cdot \left(x \cdot \left(-0.5 + \left(x \cdot x\right) \cdot 0.20833333333333334\right)\right)\\
        
        \mathbf{else}:\\
        \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 1.8999999999999999

          1. Initial program 100.0%

            \[\frac{2}{e^{x} + e^{-x}} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \color{blue}{1 + {x}^{2} \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)} \]
          4. Step-by-step derivation
            1. +-lowering-+.f64N/A

              \[\leadsto \mathsf{+.f64}\left(1, \color{blue}{\left({x}^{2} \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)\right)}\right) \]
            2. unpow2N/A

              \[\leadsto \mathsf{+.f64}\left(1, \left(\left(x \cdot x\right) \cdot \left(\color{blue}{\frac{5}{24} \cdot {x}^{2}} - \frac{1}{2}\right)\right)\right) \]
            3. associate-*l*N/A

              \[\leadsto \mathsf{+.f64}\left(1, \left(x \cdot \color{blue}{\left(x \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)\right)}\right)\right) \]
            4. *-lowering-*.f64N/A

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \color{blue}{\left(x \cdot \left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)\right)}\right)\right) \]
            5. *-lowering-*.f64N/A

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left(\frac{5}{24} \cdot {x}^{2} - \frac{1}{2}\right)}\right)\right)\right) \]
            6. sub-negN/A

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{5}{24} \cdot {x}^{2} + \color{blue}{\left(\mathsf{neg}\left(\frac{1}{2}\right)\right)}\right)\right)\right)\right) \]
            7. metadata-evalN/A

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{5}{24} \cdot {x}^{2} + \frac{-1}{2}\right)\right)\right)\right) \]
            8. +-commutativeN/A

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(\frac{-1}{2} + \color{blue}{\frac{5}{24} \cdot {x}^{2}}\right)\right)\right)\right) \]
            9. +-lowering-+.f64N/A

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{2}, \color{blue}{\left(\frac{5}{24} \cdot {x}^{2}\right)}\right)\right)\right)\right) \]
            10. *-commutativeN/A

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{2}, \left({x}^{2} \cdot \color{blue}{\frac{5}{24}}\right)\right)\right)\right)\right) \]
            11. *-lowering-*.f64N/A

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{5}{24}}\right)\right)\right)\right)\right) \]
            12. unpow2N/A

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{5}{24}\right)\right)\right)\right)\right) \]
            13. *-lowering-*.f6464.4%

              \[\leadsto \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{+.f64}\left(\frac{-1}{2}, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{5}{24}\right)\right)\right)\right)\right) \]
          5. Simplified64.4%

            \[\leadsto \color{blue}{1 + x \cdot \left(x \cdot \left(-0.5 + \left(x \cdot x\right) \cdot 0.20833333333333334\right)\right)} \]

          if 1.8999999999999999 < x

          1. Initial program 100.0%

            \[\frac{2}{e^{x} + e^{-x}} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
          4. Step-by-step derivation
            1. +-lowering-+.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right)\right) \]
            2. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right) \]
            3. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
            4. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
            5. +-lowering-+.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right)\right) \]
            6. *-commutativeN/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \left({x}^{2} \cdot \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
            7. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
            8. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
            9. *-lowering-*.f6479.5%

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
          5. Simplified79.5%

            \[\leadsto \frac{2}{\color{blue}{2 + \left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)}} \]
          6. Taylor expanded in x around inf

            \[\leadsto \color{blue}{\frac{24}{{x}^{4}}} \]
          7. Step-by-step derivation
            1. /-lowering-/.f64N/A

              \[\leadsto \mathsf{/.f64}\left(24, \color{blue}{\left({x}^{4}\right)}\right) \]
            2. metadata-evalN/A

              \[\leadsto \mathsf{/.f64}\left(24, \left({x}^{\left(3 + \color{blue}{1}\right)}\right)\right) \]
            3. pow-plusN/A

              \[\leadsto \mathsf{/.f64}\left(24, \left({x}^{3} \cdot \color{blue}{x}\right)\right) \]
            4. *-commutativeN/A

              \[\leadsto \mathsf{/.f64}\left(24, \left(x \cdot \color{blue}{{x}^{3}}\right)\right) \]
            5. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{3}\right)}\right)\right) \]
            6. cube-multN/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)\right) \]
            7. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \left(x \cdot {x}^{\color{blue}{2}}\right)\right)\right) \]
            8. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right)\right) \]
            9. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right)\right) \]
            10. *-lowering-*.f6479.5%

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right)\right) \]
          8. Simplified79.5%

            \[\leadsto \color{blue}{\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}} \]
        3. Recombined 2 regimes into one program.
        4. Add Preprocessing

        Alternative 7: 87.7% accurate, 13.7× speedup?

        \[\begin{array}{l} \\ \frac{2}{2 + \left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)} \end{array} \]
        (FPCore (x)
         :precision binary64
         (/ 2.0 (+ 2.0 (* (* x x) (+ 1.0 (* (* x x) 0.08333333333333333))))))
        double code(double x) {
        	return 2.0 / (2.0 + ((x * x) * (1.0 + ((x * x) * 0.08333333333333333))));
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            code = 2.0d0 / (2.0d0 + ((x * x) * (1.0d0 + ((x * x) * 0.08333333333333333d0))))
        end function
        
        public static double code(double x) {
        	return 2.0 / (2.0 + ((x * x) * (1.0 + ((x * x) * 0.08333333333333333))));
        }
        
        def code(x):
        	return 2.0 / (2.0 + ((x * x) * (1.0 + ((x * x) * 0.08333333333333333))))
        
        function code(x)
        	return Float64(2.0 / Float64(2.0 + Float64(Float64(x * x) * Float64(1.0 + Float64(Float64(x * x) * 0.08333333333333333)))))
        end
        
        function tmp = code(x)
        	tmp = 2.0 / (2.0 + ((x * x) * (1.0 + ((x * x) * 0.08333333333333333))));
        end
        
        code[x_] := N[(2.0 / N[(2.0 + N[(N[(x * x), $MachinePrecision] * N[(1.0 + N[(N[(x * x), $MachinePrecision] * 0.08333333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \frac{2}{2 + \left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)}
        \end{array}
        
        Derivation
        1. Initial program 100.0%

          \[\frac{2}{e^{x} + e^{-x}} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
        4. Step-by-step derivation
          1. +-lowering-+.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right)\right) \]
          2. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right) \]
          3. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
          4. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
          5. +-lowering-+.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right)\right) \]
          6. *-commutativeN/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \left({x}^{2} \cdot \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
          7. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
          8. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
          9. *-lowering-*.f6490.2%

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
        5. Simplified90.2%

          \[\leadsto \frac{2}{\color{blue}{2 + \left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)}} \]
        6. Add Preprocessing

        Alternative 8: 81.9% accurate, 14.7× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 3.7:\\ \;\;\;\;\frac{2}{2 + x \cdot x}\\ \mathbf{else}:\\ \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\ \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (if (<= x 3.7) (/ 2.0 (+ 2.0 (* x x))) (/ 24.0 (* x (* x (* x x))))))
        double code(double x) {
        	double tmp;
        	if (x <= 3.7) {
        		tmp = 2.0 / (2.0 + (x * x));
        	} else {
        		tmp = 24.0 / (x * (x * (x * x)));
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if (x <= 3.7d0) then
                tmp = 2.0d0 / (2.0d0 + (x * x))
            else
                tmp = 24.0d0 / (x * (x * (x * x)))
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if (x <= 3.7) {
        		tmp = 2.0 / (2.0 + (x * x));
        	} else {
        		tmp = 24.0 / (x * (x * (x * x)));
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if x <= 3.7:
        		tmp = 2.0 / (2.0 + (x * x))
        	else:
        		tmp = 24.0 / (x * (x * (x * x)))
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if (x <= 3.7)
        		tmp = Float64(2.0 / Float64(2.0 + Float64(x * x)));
        	else
        		tmp = Float64(24.0 / Float64(x * Float64(x * Float64(x * x))));
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if (x <= 3.7)
        		tmp = 2.0 / (2.0 + (x * x));
        	else
        		tmp = 24.0 / (x * (x * (x * x)));
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[LessEqual[x, 3.7], N[(2.0 / N[(2.0 + N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(24.0 / N[(x * N[(x * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq 3.7:\\
        \;\;\;\;\frac{2}{2 + x \cdot x}\\
        
        \mathbf{else}:\\
        \;\;\;\;\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 3.7000000000000002

          1. Initial program 100.0%

            \[\frac{2}{e^{x} + e^{-x}} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
          4. Step-by-step derivation
            1. +-lowering-+.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
            2. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
            3. *-lowering-*.f6483.0%

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
          5. Simplified83.0%

            \[\leadsto \frac{2}{\color{blue}{2 + x \cdot x}} \]

          if 3.7000000000000002 < x

          1. Initial program 100.0%

            \[\frac{2}{e^{x} + e^{-x}} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
          4. Step-by-step derivation
            1. +-lowering-+.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right)\right) \]
            2. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right) \]
            3. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
            4. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
            5. +-lowering-+.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right)\right) \]
            6. *-commutativeN/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \left({x}^{2} \cdot \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
            7. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
            8. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
            9. *-lowering-*.f6479.5%

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
          5. Simplified79.5%

            \[\leadsto \frac{2}{\color{blue}{2 + \left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)}} \]
          6. Taylor expanded in x around inf

            \[\leadsto \color{blue}{\frac{24}{{x}^{4}}} \]
          7. Step-by-step derivation
            1. /-lowering-/.f64N/A

              \[\leadsto \mathsf{/.f64}\left(24, \color{blue}{\left({x}^{4}\right)}\right) \]
            2. metadata-evalN/A

              \[\leadsto \mathsf{/.f64}\left(24, \left({x}^{\left(3 + \color{blue}{1}\right)}\right)\right) \]
            3. pow-plusN/A

              \[\leadsto \mathsf{/.f64}\left(24, \left({x}^{3} \cdot \color{blue}{x}\right)\right) \]
            4. *-commutativeN/A

              \[\leadsto \mathsf{/.f64}\left(24, \left(x \cdot \color{blue}{{x}^{3}}\right)\right) \]
            5. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{3}\right)}\right)\right) \]
            6. cube-multN/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)\right) \]
            7. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \left(x \cdot {x}^{\color{blue}{2}}\right)\right)\right) \]
            8. *-lowering-*.f64N/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{\left({x}^{2}\right)}\right)\right)\right) \]
            9. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \left(x \cdot \color{blue}{x}\right)\right)\right)\right) \]
            10. *-lowering-*.f6479.5%

              \[\leadsto \mathsf{/.f64}\left(24, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right)\right) \]
          8. Simplified79.5%

            \[\leadsto \color{blue}{\frac{24}{x \cdot \left(x \cdot \left(x \cdot x\right)\right)}} \]
        3. Recombined 2 regimes into one program.
        4. Add Preprocessing

        Alternative 9: 87.3% accurate, 15.8× speedup?

        \[\begin{array}{l} \\ \frac{2}{2 + \frac{x \cdot x}{\frac{12}{x \cdot x}}} \end{array} \]
        (FPCore (x) :precision binary64 (/ 2.0 (+ 2.0 (/ (* x x) (/ 12.0 (* x x))))))
        double code(double x) {
        	return 2.0 / (2.0 + ((x * x) / (12.0 / (x * x))));
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            code = 2.0d0 / (2.0d0 + ((x * x) / (12.0d0 / (x * x))))
        end function
        
        public static double code(double x) {
        	return 2.0 / (2.0 + ((x * x) / (12.0 / (x * x))));
        }
        
        def code(x):
        	return 2.0 / (2.0 + ((x * x) / (12.0 / (x * x))))
        
        function code(x)
        	return Float64(2.0 / Float64(2.0 + Float64(Float64(x * x) / Float64(12.0 / Float64(x * x)))))
        end
        
        function tmp = code(x)
        	tmp = 2.0 / (2.0 + ((x * x) / (12.0 / (x * x))));
        end
        
        code[x_] := N[(2.0 / N[(2.0 + N[(N[(x * x), $MachinePrecision] / N[(12.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \frac{2}{2 + \frac{x \cdot x}{\frac{12}{x \cdot x}}}
        \end{array}
        
        Derivation
        1. Initial program 100.0%

          \[\frac{2}{e^{x} + e^{-x}} \]
        2. Add Preprocessing
        3. Taylor expanded in x around 0

          \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right) \]
        4. Step-by-step derivation
          1. +-lowering-+.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2} \cdot \left(1 + \frac{1}{12} \cdot {x}^{2}\right)\right)}\right)\right) \]
          2. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\left(1 + \frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right) \]
          3. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\left(x \cdot x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
          4. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\color{blue}{1} + \frac{1}{12} \cdot {x}^{2}\right)\right)\right)\right) \]
          5. +-lowering-+.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \color{blue}{\left(\frac{1}{12} \cdot {x}^{2}\right)}\right)\right)\right)\right) \]
          6. *-commutativeN/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \left({x}^{2} \cdot \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
          7. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left({x}^{2}\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right) \]
          8. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
          9. *-lowering-*.f6490.2%

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right)\right) \]
        5. Simplified90.2%

          \[\leadsto \frac{2}{\color{blue}{2 + \left(x \cdot x\right) \cdot \left(1 + \left(x \cdot x\right) \cdot 0.08333333333333333\right)}} \]
        6. Step-by-step derivation
          1. flip3-+N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(\left(x \cdot x\right) \cdot \frac{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}{\color{blue}{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}}\right)\right)\right) \]
          2. clear-numN/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(\left(x \cdot x\right) \cdot \frac{1}{\color{blue}{\frac{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}}}\right)\right)\right) \]
          3. un-div-invN/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(\frac{x \cdot x}{\color{blue}{\frac{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}}}\right)\right)\right) \]
          4. /-lowering-/.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\left(x \cdot x\right), \color{blue}{\left(\frac{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}\right)}\right)\right)\right) \]
          5. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{\color{blue}{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}}{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}\right)\right)\right)\right) \]
          6. clear-numN/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{\color{blue}{\frac{{1}^{3} + {\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}^{3}}{1 \cdot 1 + \left(\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right) - 1 \cdot \left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)\right)}}}\right)\right)\right)\right) \]
          7. flip3-+N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \left(\frac{1}{1 + \color{blue}{\left(x \cdot x\right) \cdot \frac{1}{12}}}\right)\right)\right)\right) \]
          8. /-lowering-/.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(1, \color{blue}{\left(1 + \left(x \cdot x\right) \cdot \frac{1}{12}\right)}\right)\right)\right)\right) \]
          9. +-lowering-+.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \color{blue}{\left(\left(x \cdot x\right) \cdot \frac{1}{12}\right)}\right)\right)\right)\right)\right) \]
          10. *-lowering-*.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\left(x \cdot x\right), \color{blue}{\frac{1}{12}}\right)\right)\right)\right)\right)\right) \]
          11. *-lowering-*.f6490.2%

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(1, \mathsf{+.f64}\left(1, \mathsf{*.f64}\left(\mathsf{*.f64}\left(x, x\right), \frac{1}{12}\right)\right)\right)\right)\right)\right) \]
        7. Applied egg-rr90.2%

          \[\leadsto \frac{2}{2 + \color{blue}{\frac{x \cdot x}{\frac{1}{1 + \left(x \cdot x\right) \cdot 0.08333333333333333}}}} \]
        8. Taylor expanded in x around inf

          \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \color{blue}{\left(\frac{12}{{x}^{2}}\right)}\right)\right)\right) \]
        9. Step-by-step derivation
          1. /-lowering-/.f64N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(12, \color{blue}{\left({x}^{2}\right)}\right)\right)\right)\right) \]
          2. unpow2N/A

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(12, \left(x \cdot \color{blue}{x}\right)\right)\right)\right)\right) \]
          3. *-lowering-*.f6490.0%

            \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{/.f64}\left(\mathsf{*.f64}\left(x, x\right), \mathsf{/.f64}\left(12, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right)\right)\right) \]
        10. Simplified90.0%

          \[\leadsto \frac{2}{2 + \frac{x \cdot x}{\color{blue}{\frac{12}{x \cdot x}}}} \]
        11. Add Preprocessing

        Alternative 10: 62.7% accurate, 20.6× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 1.45:\\ \;\;\;\;1\\ \mathbf{else}:\\ \;\;\;\;\frac{2}{x \cdot x}\\ \end{array} \end{array} \]
        (FPCore (x) :precision binary64 (if (<= x 1.45) 1.0 (/ 2.0 (* x x))))
        double code(double x) {
        	double tmp;
        	if (x <= 1.45) {
        		tmp = 1.0;
        	} else {
        		tmp = 2.0 / (x * x);
        	}
        	return tmp;
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: tmp
            if (x <= 1.45d0) then
                tmp = 1.0d0
            else
                tmp = 2.0d0 / (x * x)
            end if
            code = tmp
        end function
        
        public static double code(double x) {
        	double tmp;
        	if (x <= 1.45) {
        		tmp = 1.0;
        	} else {
        		tmp = 2.0 / (x * x);
        	}
        	return tmp;
        }
        
        def code(x):
        	tmp = 0
        	if x <= 1.45:
        		tmp = 1.0
        	else:
        		tmp = 2.0 / (x * x)
        	return tmp
        
        function code(x)
        	tmp = 0.0
        	if (x <= 1.45)
        		tmp = 1.0;
        	else
        		tmp = Float64(2.0 / Float64(x * x));
        	end
        	return tmp
        end
        
        function tmp_2 = code(x)
        	tmp = 0.0;
        	if (x <= 1.45)
        		tmp = 1.0;
        	else
        		tmp = 2.0 / (x * x);
        	end
        	tmp_2 = tmp;
        end
        
        code[x_] := If[LessEqual[x, 1.45], 1.0, N[(2.0 / N[(x * x), $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;x \leq 1.45:\\
        \;\;\;\;1\\
        
        \mathbf{else}:\\
        \;\;\;\;\frac{2}{x \cdot x}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if x < 1.44999999999999996

          1. Initial program 100.0%

            \[\frac{2}{e^{x} + e^{-x}} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \color{blue}{1} \]
          4. Step-by-step derivation
            1. Simplified64.7%

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

            if 1.44999999999999996 < x

            1. Initial program 100.0%

              \[\frac{2}{e^{x} + e^{-x}} \]
            2. Add Preprocessing
            3. Taylor expanded in x around 0

              \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
            4. Step-by-step derivation
              1. +-lowering-+.f64N/A

                \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
              2. unpow2N/A

                \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
              3. *-lowering-*.f6458.8%

                \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
            5. Simplified58.8%

              \[\leadsto \frac{2}{\color{blue}{2 + x \cdot x}} \]
            6. Taylor expanded in x around inf

              \[\leadsto \color{blue}{\frac{2}{{x}^{2}}} \]
            7. Step-by-step derivation
              1. /-lowering-/.f64N/A

                \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right) \]
              2. unpow2N/A

                \[\leadsto \mathsf{/.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right) \]
              3. *-lowering-*.f6458.8%

                \[\leadsto \mathsf{/.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right) \]
            8. Simplified58.8%

              \[\leadsto \color{blue}{\frac{2}{x \cdot x}} \]
          5. Recombined 2 regimes into one program.
          6. Add Preprocessing

          Alternative 11: 75.7% accurate, 29.4× speedup?

          \[\begin{array}{l} \\ \frac{2}{2 + x \cdot x} \end{array} \]
          (FPCore (x) :precision binary64 (/ 2.0 (+ 2.0 (* x x))))
          double code(double x) {
          	return 2.0 / (2.0 + (x * x));
          }
          
          real(8) function code(x)
              real(8), intent (in) :: x
              code = 2.0d0 / (2.0d0 + (x * x))
          end function
          
          public static double code(double x) {
          	return 2.0 / (2.0 + (x * x));
          }
          
          def code(x):
          	return 2.0 / (2.0 + (x * x))
          
          function code(x)
          	return Float64(2.0 / Float64(2.0 + Float64(x * x)))
          end
          
          function tmp = code(x)
          	tmp = 2.0 / (2.0 + (x * x));
          end
          
          code[x_] := N[(2.0 / N[(2.0 + N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{2}{2 + x \cdot x}
          \end{array}
          
          Derivation
          1. Initial program 100.0%

            \[\frac{2}{e^{x} + e^{-x}} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \mathsf{/.f64}\left(2, \color{blue}{\left(2 + {x}^{2}\right)}\right) \]
          4. Step-by-step derivation
            1. +-lowering-+.f64N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \color{blue}{\left({x}^{2}\right)}\right)\right) \]
            2. unpow2N/A

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \left(x \cdot \color{blue}{x}\right)\right)\right) \]
            3. *-lowering-*.f6476.5%

              \[\leadsto \mathsf{/.f64}\left(2, \mathsf{+.f64}\left(2, \mathsf{*.f64}\left(x, \color{blue}{x}\right)\right)\right) \]
          5. Simplified76.5%

            \[\leadsto \frac{2}{\color{blue}{2 + x \cdot x}} \]
          6. Add Preprocessing

          Alternative 12: 49.9% accurate, 206.0× speedup?

          \[\begin{array}{l} \\ 1 \end{array} \]
          (FPCore (x) :precision binary64 1.0)
          double code(double x) {
          	return 1.0;
          }
          
          real(8) function code(x)
              real(8), intent (in) :: x
              code = 1.0d0
          end function
          
          public static double code(double x) {
          	return 1.0;
          }
          
          def code(x):
          	return 1.0
          
          function code(x)
          	return 1.0
          end
          
          function tmp = code(x)
          	tmp = 1.0;
          end
          
          code[x_] := 1.0
          
          \begin{array}{l}
          
          \\
          1
          \end{array}
          
          Derivation
          1. Initial program 100.0%

            \[\frac{2}{e^{x} + e^{-x}} \]
          2. Add Preprocessing
          3. Taylor expanded in x around 0

            \[\leadsto \color{blue}{1} \]
          4. Step-by-step derivation
            1. Simplified48.1%

              \[\leadsto \color{blue}{1} \]
            2. Add Preprocessing

            Reproduce

            ?
            herbie shell --seed 2024161 
            (FPCore (x)
              :name "Hyperbolic secant"
              :precision binary64
              (/ 2.0 (+ (exp x) (exp (- x)))))