Hyperbolic secant

Percentage Accurate: 100.0% → 100.0%
Time: 5.3s
Alternatives: 8
Speedup: 1.1×

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 8 alternatives:

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

Initial Program: 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, 1.1× speedup?

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

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

    \[\frac{2}{e^{x} + e^{-x}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-/.f64N/A

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

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

      \[\leadsto \frac{2}{\color{blue}{e^{x}} + e^{-x}} \]
    4. lift-exp.f64N/A

      \[\leadsto \frac{2}{e^{x} + \color{blue}{e^{-x}}} \]
    5. lift-neg.f64N/A

      \[\leadsto \frac{2}{e^{x} + e^{\color{blue}{\mathsf{neg}\left(x\right)}}} \]
    6. cosh-undefN/A

      \[\leadsto \frac{2}{\color{blue}{2 \cdot \cosh x}} \]
    7. associate-/r*N/A

      \[\leadsto \color{blue}{\frac{\frac{2}{2}}{\cosh x}} \]
    8. metadata-evalN/A

      \[\leadsto \frac{\color{blue}{1}}{\cosh x} \]
    9. lower-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
    10. lower-cosh.f64100.0

      \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
  4. Applied rewrites100.0%

    \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
  5. Final simplification100.0%

    \[\leadsto {\cosh x}^{-1} \]
  6. Add Preprocessing

Alternative 2: 74.9% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := 0.041666666666666664 \cdot \left(x \cdot x\right)\\ t_1 := \left(t\_0 \cdot x\right) \cdot x\\ \mathbf{if}\;x \leq 2.5 \cdot 10^{+77}:\\ \;\;\;\;{\left(\frac{1 - t\_1 \cdot t\_1}{1 - t\_1}\right)}^{-1}\\ \mathbf{else}:\\ \;\;\;\;{\left(\mathsf{fma}\left(t\_0, x \cdot x, 1\right)\right)}^{-1}\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (* 0.041666666666666664 (* x x))) (t_1 (* (* t_0 x) x)))
   (if (<= x 2.5e+77)
     (pow (/ (- 1.0 (* t_1 t_1)) (- 1.0 t_1)) -1.0)
     (pow (fma t_0 (* x x) 1.0) -1.0))))
double code(double x) {
	double t_0 = 0.041666666666666664 * (x * x);
	double t_1 = (t_0 * x) * x;
	double tmp;
	if (x <= 2.5e+77) {
		tmp = pow(((1.0 - (t_1 * t_1)) / (1.0 - t_1)), -1.0);
	} else {
		tmp = pow(fma(t_0, (x * x), 1.0), -1.0);
	}
	return tmp;
}
function code(x)
	t_0 = Float64(0.041666666666666664 * Float64(x * x))
	t_1 = Float64(Float64(t_0 * x) * x)
	tmp = 0.0
	if (x <= 2.5e+77)
		tmp = Float64(Float64(1.0 - Float64(t_1 * t_1)) / Float64(1.0 - t_1)) ^ -1.0;
	else
		tmp = fma(t_0, Float64(x * x), 1.0) ^ -1.0;
	end
	return tmp
end
code[x_] := Block[{t$95$0 = N[(0.041666666666666664 * N[(x * x), $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(t$95$0 * x), $MachinePrecision] * x), $MachinePrecision]}, If[LessEqual[x, 2.5e+77], N[Power[N[(N[(1.0 - N[(t$95$1 * t$95$1), $MachinePrecision]), $MachinePrecision] / N[(1.0 - t$95$1), $MachinePrecision]), $MachinePrecision], -1.0], $MachinePrecision], N[Power[N[(t$95$0 * N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision], -1.0], $MachinePrecision]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := 0.041666666666666664 \cdot \left(x \cdot x\right)\\
t_1 := \left(t\_0 \cdot x\right) \cdot x\\
\mathbf{if}\;x \leq 2.5 \cdot 10^{+77}:\\
\;\;\;\;{\left(\frac{1 - t\_1 \cdot t\_1}{1 - t\_1}\right)}^{-1}\\

\mathbf{else}:\\
\;\;\;\;{\left(\mathsf{fma}\left(t\_0, x \cdot x, 1\right)\right)}^{-1}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 2.50000000000000002e77

    1. Initial program 100.0%

      \[\frac{2}{e^{x} + e^{-x}} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift-/.f64N/A

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

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

        \[\leadsto \frac{2}{\color{blue}{e^{x}} + e^{-x}} \]
      4. lift-exp.f64N/A

        \[\leadsto \frac{2}{e^{x} + \color{blue}{e^{-x}}} \]
      5. lift-neg.f64N/A

        \[\leadsto \frac{2}{e^{x} + e^{\color{blue}{\mathsf{neg}\left(x\right)}}} \]
      6. cosh-undefN/A

        \[\leadsto \frac{2}{\color{blue}{2 \cdot \cosh x}} \]
      7. associate-/r*N/A

        \[\leadsto \color{blue}{\frac{\frac{2}{2}}{\cosh x}} \]
      8. metadata-evalN/A

        \[\leadsto \frac{\color{blue}{1}}{\cosh x} \]
      9. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
      10. lower-cosh.f64100.0

        \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
    4. Applied rewrites100.0%

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

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

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

        \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right) \cdot {x}^{2}} + 1} \]
      3. lower-fma.f64N/A

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

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

        \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\frac{1}{24}, {x}^{2}, \frac{1}{2}\right)}, {x}^{2}, 1\right)} \]
      6. unpow2N/A

        \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24}, \color{blue}{x \cdot x}, \frac{1}{2}\right), {x}^{2}, 1\right)} \]
      7. lower-*.f64N/A

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

        \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24}, x \cdot x, \frac{1}{2}\right), \color{blue}{x \cdot x}, 1\right)} \]
      9. lower-*.f6483.8

        \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x \cdot x, 0.5\right), \color{blue}{x \cdot x}, 1\right)} \]
    7. Applied rewrites83.8%

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

      \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{1}{24} \cdot {x}^{2}, \color{blue}{x} \cdot x, 1\right)} \]
    9. Step-by-step derivation
      1. Applied rewrites83.6%

        \[\leadsto \frac{1}{\mathsf{fma}\left(0.041666666666666664 \cdot \left(x \cdot x\right), \color{blue}{x} \cdot x, 1\right)} \]
      2. Step-by-step derivation
        1. Applied rewrites66.4%

          \[\leadsto \frac{1}{\frac{1 - \left(\left(-\left(0.041666666666666664 \cdot \left(x \cdot x\right)\right) \cdot x\right) \cdot x\right) \cdot \left(\left(-\left(0.041666666666666664 \cdot \left(x \cdot x\right)\right) \cdot x\right) \cdot x\right)}{\color{blue}{1 + \left(-\left(0.041666666666666664 \cdot \left(x \cdot x\right)\right) \cdot x\right) \cdot x}}} \]

        if 2.50000000000000002e77 < x

        1. Initial program 100.0%

          \[\frac{2}{e^{x} + e^{-x}} \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift-/.f64N/A

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

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

            \[\leadsto \frac{2}{\color{blue}{e^{x}} + e^{-x}} \]
          4. lift-exp.f64N/A

            \[\leadsto \frac{2}{e^{x} + \color{blue}{e^{-x}}} \]
          5. lift-neg.f64N/A

            \[\leadsto \frac{2}{e^{x} + e^{\color{blue}{\mathsf{neg}\left(x\right)}}} \]
          6. cosh-undefN/A

            \[\leadsto \frac{2}{\color{blue}{2 \cdot \cosh x}} \]
          7. associate-/r*N/A

            \[\leadsto \color{blue}{\frac{\frac{2}{2}}{\cosh x}} \]
          8. metadata-evalN/A

            \[\leadsto \frac{\color{blue}{1}}{\cosh x} \]
          9. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
          10. lower-cosh.f64100.0

            \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
        4. Applied rewrites100.0%

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

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

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

            \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right) \cdot {x}^{2}} + 1} \]
          3. lower-fma.f64N/A

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

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

            \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\frac{1}{24}, {x}^{2}, \frac{1}{2}\right)}, {x}^{2}, 1\right)} \]
          6. unpow2N/A

            \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24}, \color{blue}{x \cdot x}, \frac{1}{2}\right), {x}^{2}, 1\right)} \]
          7. lower-*.f64N/A

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

            \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24}, x \cdot x, \frac{1}{2}\right), \color{blue}{x \cdot x}, 1\right)} \]
          9. lower-*.f64100.0

            \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x \cdot x, 0.5\right), \color{blue}{x \cdot x}, 1\right)} \]
        7. Applied rewrites100.0%

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

          \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{1}{24} \cdot {x}^{2}, \color{blue}{x} \cdot x, 1\right)} \]
        9. Step-by-step derivation
          1. Applied rewrites100.0%

            \[\leadsto \frac{1}{\mathsf{fma}\left(0.041666666666666664 \cdot \left(x \cdot x\right), \color{blue}{x} \cdot x, 1\right)} \]
        10. Recombined 2 regimes into one program.
        11. Final simplification72.3%

          \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 2.5 \cdot 10^{+77}:\\ \;\;\;\;{\left(\frac{1 - \left(\left(\left(0.041666666666666664 \cdot \left(x \cdot x\right)\right) \cdot x\right) \cdot x\right) \cdot \left(\left(\left(0.041666666666666664 \cdot \left(x \cdot x\right)\right) \cdot x\right) \cdot x\right)}{1 - \left(\left(0.041666666666666664 \cdot \left(x \cdot x\right)\right) \cdot x\right) \cdot x}\right)}^{-1}\\ \mathbf{else}:\\ \;\;\;\;{\left(\mathsf{fma}\left(0.041666666666666664 \cdot \left(x \cdot x\right), x \cdot x, 1\right)\right)}^{-1}\\ \end{array} \]
        12. Add Preprocessing

        Alternative 3: 92.1% accurate, 1.6× speedup?

        \[\begin{array}{l} \\ {\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), x \cdot x, 0.5\right) \cdot x, x, 1\right)\right)}^{-1} \end{array} \]
        (FPCore (x)
         :precision binary64
         (pow
          (fma
           (*
            (fma (fma (* x x) 0.001388888888888889 0.041666666666666664) (* x x) 0.5)
            x)
           x
           1.0)
          -1.0))
        double code(double x) {
        	return pow(fma((fma(fma((x * x), 0.001388888888888889, 0.041666666666666664), (x * x), 0.5) * x), x, 1.0), -1.0);
        }
        
        function code(x)
        	return fma(Float64(fma(fma(Float64(x * x), 0.001388888888888889, 0.041666666666666664), Float64(x * x), 0.5) * x), x, 1.0) ^ -1.0
        end
        
        code[x_] := N[Power[N[(N[(N[(N[(N[(x * x), $MachinePrecision] * 0.001388888888888889 + 0.041666666666666664), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.5), $MachinePrecision] * x), $MachinePrecision] * x + 1.0), $MachinePrecision], -1.0], $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        {\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), x \cdot x, 0.5\right) \cdot x, x, 1\right)\right)}^{-1}
        \end{array}
        
        Derivation
        1. Initial program 100.0%

          \[\frac{2}{e^{x} + e^{-x}} \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift-/.f64N/A

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

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

            \[\leadsto \frac{2}{\color{blue}{e^{x}} + e^{-x}} \]
          4. lift-exp.f64N/A

            \[\leadsto \frac{2}{e^{x} + \color{blue}{e^{-x}}} \]
          5. lift-neg.f64N/A

            \[\leadsto \frac{2}{e^{x} + e^{\color{blue}{\mathsf{neg}\left(x\right)}}} \]
          6. cosh-undefN/A

            \[\leadsto \frac{2}{\color{blue}{2 \cdot \cosh x}} \]
          7. associate-/r*N/A

            \[\leadsto \color{blue}{\frac{\frac{2}{2}}{\cosh x}} \]
          8. metadata-evalN/A

            \[\leadsto \frac{\color{blue}{1}}{\cosh x} \]
          9. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
          10. lower-cosh.f64100.0

            \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
        4. Applied rewrites100.0%

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

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

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

            \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) \cdot {x}^{2}} + 1} \]
          3. lower-fma.f64N/A

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

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

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

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

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

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

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

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

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

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

            \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{720}, x \cdot x, \frac{1}{24}\right), x \cdot x, \frac{1}{2}\right), \color{blue}{x \cdot x}, 1\right)} \]
          14. lower-*.f6491.2

            \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.001388888888888889, x \cdot x, 0.041666666666666664\right), x \cdot x, 0.5\right), \color{blue}{x \cdot x}, 1\right)} \]
        7. Applied rewrites91.2%

          \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.001388888888888889, x \cdot x, 0.041666666666666664\right), x \cdot x, 0.5\right), x \cdot x, 1\right)}} \]
        8. Step-by-step derivation
          1. Applied rewrites91.2%

            \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), x \cdot x, 0.5\right) \cdot x, \color{blue}{x}, 1\right)} \]
          2. Final simplification91.2%

            \[\leadsto {\left(\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(x \cdot x, 0.001388888888888889, 0.041666666666666664\right), x \cdot x, 0.5\right) \cdot x, x, 1\right)\right)}^{-1} \]
          3. Add Preprocessing

          Alternative 4: 92.0% accurate, 1.6× speedup?

          \[\begin{array}{l} \\ {\left(\mathsf{fma}\left(\mathsf{fma}\left(0.001388888888888889 \cdot \left(x \cdot x\right), x \cdot x, 0.5\right) \cdot x, x, 1\right)\right)}^{-1} \end{array} \]
          (FPCore (x)
           :precision binary64
           (pow
            (fma (* (fma (* 0.001388888888888889 (* x x)) (* x x) 0.5) x) x 1.0)
            -1.0))
          double code(double x) {
          	return pow(fma((fma((0.001388888888888889 * (x * x)), (x * x), 0.5) * x), x, 1.0), -1.0);
          }
          
          function code(x)
          	return fma(Float64(fma(Float64(0.001388888888888889 * Float64(x * x)), Float64(x * x), 0.5) * x), x, 1.0) ^ -1.0
          end
          
          code[x_] := N[Power[N[(N[(N[(N[(0.001388888888888889 * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + 0.5), $MachinePrecision] * x), $MachinePrecision] * x + 1.0), $MachinePrecision], -1.0], $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          {\left(\mathsf{fma}\left(\mathsf{fma}\left(0.001388888888888889 \cdot \left(x \cdot x\right), x \cdot x, 0.5\right) \cdot x, x, 1\right)\right)}^{-1}
          \end{array}
          
          Derivation
          1. Initial program 100.0%

            \[\frac{2}{e^{x} + e^{-x}} \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-/.f64N/A

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

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

              \[\leadsto \frac{2}{\color{blue}{e^{x}} + e^{-x}} \]
            4. lift-exp.f64N/A

              \[\leadsto \frac{2}{e^{x} + \color{blue}{e^{-x}}} \]
            5. lift-neg.f64N/A

              \[\leadsto \frac{2}{e^{x} + e^{\color{blue}{\mathsf{neg}\left(x\right)}}} \]
            6. cosh-undefN/A

              \[\leadsto \frac{2}{\color{blue}{2 \cdot \cosh x}} \]
            7. associate-/r*N/A

              \[\leadsto \color{blue}{\frac{\frac{2}{2}}{\cosh x}} \]
            8. metadata-evalN/A

              \[\leadsto \frac{\color{blue}{1}}{\cosh x} \]
            9. lower-/.f64N/A

              \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
            10. lower-cosh.f64100.0

              \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
          4. Applied rewrites100.0%

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

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

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

              \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{2} + {x}^{2} \cdot \left(\frac{1}{24} + \frac{1}{720} \cdot {x}^{2}\right)\right) \cdot {x}^{2}} + 1} \]
            3. lower-fma.f64N/A

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

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

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

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

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

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

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

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

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

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

              \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{720}, x \cdot x, \frac{1}{24}\right), x \cdot x, \frac{1}{2}\right), \color{blue}{x \cdot x}, 1\right)} \]
            14. lower-*.f6491.2

              \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(0.001388888888888889, x \cdot x, 0.041666666666666664\right), x \cdot x, 0.5\right), \color{blue}{x \cdot x}, 1\right)} \]
          7. Applied rewrites91.2%

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

            \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{720} \cdot {x}^{2}, x \cdot x, \frac{1}{2}\right), x \cdot x, 1\right)} \]
          9. Step-by-step derivation
            1. Applied rewrites91.1%

              \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.001388888888888889 \cdot \left(x \cdot x\right), x \cdot x, 0.5\right), x \cdot x, 1\right)} \]
            2. Step-by-step derivation
              1. Applied rewrites91.1%

                \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.001388888888888889 \cdot \left(x \cdot x\right), x \cdot x, 0.5\right) \cdot x, \color{blue}{x}, 1\right)} \]
              2. Final simplification91.1%

                \[\leadsto {\left(\mathsf{fma}\left(\mathsf{fma}\left(0.001388888888888889 \cdot \left(x \cdot x\right), x \cdot x, 0.5\right) \cdot x, x, 1\right)\right)}^{-1} \]
              3. Add Preprocessing

              Alternative 5: 88.2% accurate, 1.8× speedup?

              \[\begin{array}{l} \\ {\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x \cdot x, 0.5\right) \cdot x, x, 1\right)\right)}^{-1} \end{array} \]
              (FPCore (x)
               :precision binary64
               (pow (fma (* (fma 0.041666666666666664 (* x x) 0.5) x) x 1.0) -1.0))
              double code(double x) {
              	return pow(fma((fma(0.041666666666666664, (x * x), 0.5) * x), x, 1.0), -1.0);
              }
              
              function code(x)
              	return fma(Float64(fma(0.041666666666666664, Float64(x * x), 0.5) * x), x, 1.0) ^ -1.0
              end
              
              code[x_] := N[Power[N[(N[(N[(0.041666666666666664 * N[(x * x), $MachinePrecision] + 0.5), $MachinePrecision] * x), $MachinePrecision] * x + 1.0), $MachinePrecision], -1.0], $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              {\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x \cdot x, 0.5\right) \cdot x, x, 1\right)\right)}^{-1}
              \end{array}
              
              Derivation
              1. Initial program 100.0%

                \[\frac{2}{e^{x} + e^{-x}} \]
              2. Add Preprocessing
              3. Step-by-step derivation
                1. lift-/.f64N/A

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

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

                  \[\leadsto \frac{2}{\color{blue}{e^{x}} + e^{-x}} \]
                4. lift-exp.f64N/A

                  \[\leadsto \frac{2}{e^{x} + \color{blue}{e^{-x}}} \]
                5. lift-neg.f64N/A

                  \[\leadsto \frac{2}{e^{x} + e^{\color{blue}{\mathsf{neg}\left(x\right)}}} \]
                6. cosh-undefN/A

                  \[\leadsto \frac{2}{\color{blue}{2 \cdot \cosh x}} \]
                7. associate-/r*N/A

                  \[\leadsto \color{blue}{\frac{\frac{2}{2}}{\cosh x}} \]
                8. metadata-evalN/A

                  \[\leadsto \frac{\color{blue}{1}}{\cosh x} \]
                9. lower-/.f64N/A

                  \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
                10. lower-cosh.f64100.0

                  \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
              4. Applied rewrites100.0%

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

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

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

                  \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right) \cdot {x}^{2}} + 1} \]
                3. lower-fma.f64N/A

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

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

                  \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\frac{1}{24}, {x}^{2}, \frac{1}{2}\right)}, {x}^{2}, 1\right)} \]
                6. unpow2N/A

                  \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24}, \color{blue}{x \cdot x}, \frac{1}{2}\right), {x}^{2}, 1\right)} \]
                7. lower-*.f64N/A

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

                  \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24}, x \cdot x, \frac{1}{2}\right), \color{blue}{x \cdot x}, 1\right)} \]
                9. lower-*.f6486.7

                  \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x \cdot x, 0.5\right), \color{blue}{x \cdot x}, 1\right)} \]
              7. Applied rewrites86.7%

                \[\leadsto \frac{1}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x \cdot x, 0.5\right), x \cdot x, 1\right)}} \]
              8. Step-by-step derivation
                1. Applied rewrites86.7%

                  \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x \cdot x, 0.5\right) \cdot x, \color{blue}{x}, 1\right)} \]
                2. Final simplification86.7%

                  \[\leadsto {\left(\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x \cdot x, 0.5\right) \cdot x, x, 1\right)\right)}^{-1} \]
                3. Add Preprocessing

                Alternative 6: 87.8% accurate, 1.8× speedup?

                \[\begin{array}{l} \\ {\left(\mathsf{fma}\left(0.041666666666666664 \cdot \left(x \cdot x\right), x \cdot x, 1\right)\right)}^{-1} \end{array} \]
                (FPCore (x)
                 :precision binary64
                 (pow (fma (* 0.041666666666666664 (* x x)) (* x x) 1.0) -1.0))
                double code(double x) {
                	return pow(fma((0.041666666666666664 * (x * x)), (x * x), 1.0), -1.0);
                }
                
                function code(x)
                	return fma(Float64(0.041666666666666664 * Float64(x * x)), Float64(x * x), 1.0) ^ -1.0
                end
                
                code[x_] := N[Power[N[(N[(0.041666666666666664 * N[(x * x), $MachinePrecision]), $MachinePrecision] * N[(x * x), $MachinePrecision] + 1.0), $MachinePrecision], -1.0], $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                {\left(\mathsf{fma}\left(0.041666666666666664 \cdot \left(x \cdot x\right), x \cdot x, 1\right)\right)}^{-1}
                \end{array}
                
                Derivation
                1. Initial program 100.0%

                  \[\frac{2}{e^{x} + e^{-x}} \]
                2. Add Preprocessing
                3. Step-by-step derivation
                  1. lift-/.f64N/A

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

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

                    \[\leadsto \frac{2}{\color{blue}{e^{x}} + e^{-x}} \]
                  4. lift-exp.f64N/A

                    \[\leadsto \frac{2}{e^{x} + \color{blue}{e^{-x}}} \]
                  5. lift-neg.f64N/A

                    \[\leadsto \frac{2}{e^{x} + e^{\color{blue}{\mathsf{neg}\left(x\right)}}} \]
                  6. cosh-undefN/A

                    \[\leadsto \frac{2}{\color{blue}{2 \cdot \cosh x}} \]
                  7. associate-/r*N/A

                    \[\leadsto \color{blue}{\frac{\frac{2}{2}}{\cosh x}} \]
                  8. metadata-evalN/A

                    \[\leadsto \frac{\color{blue}{1}}{\cosh x} \]
                  9. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{1}{\cosh x}} \]
                  10. lower-cosh.f64100.0

                    \[\leadsto \frac{1}{\color{blue}{\cosh x}} \]
                4. Applied rewrites100.0%

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

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

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

                    \[\leadsto \frac{1}{\color{blue}{\left(\frac{1}{2} + \frac{1}{24} \cdot {x}^{2}\right) \cdot {x}^{2}} + 1} \]
                  3. lower-fma.f64N/A

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

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

                    \[\leadsto \frac{1}{\mathsf{fma}\left(\color{blue}{\mathsf{fma}\left(\frac{1}{24}, {x}^{2}, \frac{1}{2}\right)}, {x}^{2}, 1\right)} \]
                  6. unpow2N/A

                    \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24}, \color{blue}{x \cdot x}, \frac{1}{2}\right), {x}^{2}, 1\right)} \]
                  7. lower-*.f64N/A

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

                    \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{1}{24}, x \cdot x, \frac{1}{2}\right), \color{blue}{x \cdot x}, 1\right)} \]
                  9. lower-*.f6486.7

                    \[\leadsto \frac{1}{\mathsf{fma}\left(\mathsf{fma}\left(0.041666666666666664, x \cdot x, 0.5\right), \color{blue}{x \cdot x}, 1\right)} \]
                7. Applied rewrites86.7%

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

                  \[\leadsto \frac{1}{\mathsf{fma}\left(\frac{1}{24} \cdot {x}^{2}, \color{blue}{x} \cdot x, 1\right)} \]
                9. Step-by-step derivation
                  1. Applied rewrites86.5%

                    \[\leadsto \frac{1}{\mathsf{fma}\left(0.041666666666666664 \cdot \left(x \cdot x\right), \color{blue}{x} \cdot x, 1\right)} \]
                  2. Final simplification86.5%

                    \[\leadsto {\left(\mathsf{fma}\left(0.041666666666666664 \cdot \left(x \cdot x\right), x \cdot x, 1\right)\right)}^{-1} \]
                  3. Add Preprocessing

                  Alternative 7: 76.3% accurate, 12.1× speedup?

                  \[\begin{array}{l} \\ \frac{2}{\mathsf{fma}\left(x, x, 2\right)} \end{array} \]
                  (FPCore (x) :precision binary64 (/ 2.0 (fma x x 2.0)))
                  double code(double x) {
                  	return 2.0 / fma(x, x, 2.0);
                  }
                  
                  function code(x)
                  	return Float64(2.0 / fma(x, x, 2.0))
                  end
                  
                  code[x_] := N[(2.0 / N[(x * x + 2.0), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \frac{2}{\mathsf{fma}\left(x, x, 2\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

                    \[\leadsto \frac{2}{\color{blue}{2 + {x}^{2}}} \]
                  4. Step-by-step derivation
                    1. +-commutativeN/A

                      \[\leadsto \frac{2}{\color{blue}{{x}^{2} + 2}} \]
                    2. unpow2N/A

                      \[\leadsto \frac{2}{\color{blue}{x \cdot x} + 2} \]
                    3. lower-fma.f6473.3

                      \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x, 2\right)}} \]
                  5. Applied rewrites73.3%

                    \[\leadsto \frac{2}{\color{blue}{\mathsf{fma}\left(x, x, 2\right)}} \]
                  6. Add Preprocessing

                  Alternative 8: 51.0% accurate, 217.0× 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. Applied rewrites48.3%

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

                    Reproduce

                    ?
                    herbie shell --seed 2024326 
                    (FPCore (x)
                      :name "Hyperbolic secant"
                      :precision binary64
                      (/ 2.0 (+ (exp x) (exp (- x)))))