exp2 (problem 3.3.7)

Percentage Accurate: 53.8% → 99.9%
Time: 15.3s
Alternatives: 13
Speedup: 2.0×

Specification

?
\[\left|x\right| \leq 710\]
\[\begin{array}{l} \\ \left(e^{x} - 2\right) + e^{-x} \end{array} \]
(FPCore (x) :precision binary64 (+ (- (exp x) 2.0) (exp (- x))))
double code(double x) {
	return (exp(x) - 2.0) + exp(-x);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (exp(x) - 2.0d0) + exp(-x)
end function
public static double code(double x) {
	return (Math.exp(x) - 2.0) + Math.exp(-x);
}
def code(x):
	return (math.exp(x) - 2.0) + math.exp(-x)
function code(x)
	return Float64(Float64(exp(x) - 2.0) + exp(Float64(-x)))
end
function tmp = code(x)
	tmp = (exp(x) - 2.0) + exp(-x);
end
code[x_] := N[(N[(N[Exp[x], $MachinePrecision] - 2.0), $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\left(e^{x} - 2\right) + 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 13 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: 53.8% accurate, 1.0× speedup?

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

\\
\left(e^{x} - 2\right) + e^{-x}
\end{array}

Alternative 1: 99.9% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := e^{-x}\\ \mathbf{if}\;\left(e^{x} - 2\right) + t\_0 \leq 0.001:\\ \;\;\;\;{\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot 0.0005208333333333333\right)\right)\right)}^{2}\\ \mathbf{else}:\\ \;\;\;\;e^{x} + \left(t\_0 + -2\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (exp (- x))))
   (if (<= (+ (- (exp x) 2.0) t_0) 0.001)
     (pow
      (*
       x
       (+
        1.0
        (*
         (pow x 2.0)
         (+ 0.041666666666666664 (* (pow x 2.0) 0.0005208333333333333)))))
      2.0)
     (+ (exp x) (+ t_0 -2.0)))))
double code(double x) {
	double t_0 = exp(-x);
	double tmp;
	if (((exp(x) - 2.0) + t_0) <= 0.001) {
		tmp = pow((x * (1.0 + (pow(x, 2.0) * (0.041666666666666664 + (pow(x, 2.0) * 0.0005208333333333333))))), 2.0);
	} else {
		tmp = exp(x) + (t_0 + -2.0);
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: tmp
    t_0 = exp(-x)
    if (((exp(x) - 2.0d0) + t_0) <= 0.001d0) then
        tmp = (x * (1.0d0 + ((x ** 2.0d0) * (0.041666666666666664d0 + ((x ** 2.0d0) * 0.0005208333333333333d0))))) ** 2.0d0
    else
        tmp = exp(x) + (t_0 + (-2.0d0))
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = Math.exp(-x);
	double tmp;
	if (((Math.exp(x) - 2.0) + t_0) <= 0.001) {
		tmp = Math.pow((x * (1.0 + (Math.pow(x, 2.0) * (0.041666666666666664 + (Math.pow(x, 2.0) * 0.0005208333333333333))))), 2.0);
	} else {
		tmp = Math.exp(x) + (t_0 + -2.0);
	}
	return tmp;
}
def code(x):
	t_0 = math.exp(-x)
	tmp = 0
	if ((math.exp(x) - 2.0) + t_0) <= 0.001:
		tmp = math.pow((x * (1.0 + (math.pow(x, 2.0) * (0.041666666666666664 + (math.pow(x, 2.0) * 0.0005208333333333333))))), 2.0)
	else:
		tmp = math.exp(x) + (t_0 + -2.0)
	return tmp
function code(x)
	t_0 = exp(Float64(-x))
	tmp = 0.0
	if (Float64(Float64(exp(x) - 2.0) + t_0) <= 0.001)
		tmp = Float64(x * Float64(1.0 + Float64((x ^ 2.0) * Float64(0.041666666666666664 + Float64((x ^ 2.0) * 0.0005208333333333333))))) ^ 2.0;
	else
		tmp = Float64(exp(x) + Float64(t_0 + -2.0));
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = exp(-x);
	tmp = 0.0;
	if (((exp(x) - 2.0) + t_0) <= 0.001)
		tmp = (x * (1.0 + ((x ^ 2.0) * (0.041666666666666664 + ((x ^ 2.0) * 0.0005208333333333333))))) ^ 2.0;
	else
		tmp = exp(x) + (t_0 + -2.0);
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[Exp[(-x)], $MachinePrecision]}, If[LessEqual[N[(N[(N[Exp[x], $MachinePrecision] - 2.0), $MachinePrecision] + t$95$0), $MachinePrecision], 0.001], N[Power[N[(x * N[(1.0 + N[(N[Power[x, 2.0], $MachinePrecision] * N[(0.041666666666666664 + N[(N[Power[x, 2.0], $MachinePrecision] * 0.0005208333333333333), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision], N[(N[Exp[x], $MachinePrecision] + N[(t$95$0 + -2.0), $MachinePrecision]), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := e^{-x}\\
\mathbf{if}\;\left(e^{x} - 2\right) + t\_0 \leq 0.001:\\
\;\;\;\;{\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot 0.0005208333333333333\right)\right)\right)}^{2}\\

\mathbf{else}:\\
\;\;\;\;e^{x} + \left(t\_0 + -2\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (-.f64 (exp.f64 x) #s(literal 2 binary64)) (exp.f64 (neg.f64 x))) < 1e-3

    1. Initial program 50.5%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-50.5%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg50.5%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg50.5%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in50.5%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg50.5%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative50.5%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval50.5%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified50.5%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. +-commutative50.5%

        \[\leadsto e^{x} + \color{blue}{\left(-2 + e^{-x}\right)} \]
      2. associate-+r+50.5%

        \[\leadsto \color{blue}{\left(e^{x} + -2\right) + e^{-x}} \]
      3. metadata-eval50.5%

        \[\leadsto \left(e^{x} + \color{blue}{\left(-2\right)}\right) + e^{-x} \]
      4. sub-neg50.5%

        \[\leadsto \color{blue}{\left(e^{x} - 2\right)} + e^{-x} \]
      5. add-sqr-sqrt50.5%

        \[\leadsto \color{blue}{\sqrt{\left(e^{x} - 2\right) + e^{-x}} \cdot \sqrt{\left(e^{x} - 2\right) + e^{-x}}} \]
      6. pow250.5%

        \[\leadsto \color{blue}{{\left(\sqrt{\left(e^{x} - 2\right) + e^{-x}}\right)}^{2}} \]
      7. sub-neg50.5%

        \[\leadsto {\left(\sqrt{\color{blue}{\left(e^{x} + \left(-2\right)\right)} + e^{-x}}\right)}^{2} \]
      8. metadata-eval50.5%

        \[\leadsto {\left(\sqrt{\left(e^{x} + \color{blue}{-2}\right) + e^{-x}}\right)}^{2} \]
      9. associate-+r+50.5%

        \[\leadsto {\left(\sqrt{\color{blue}{e^{x} + \left(-2 + e^{-x}\right)}}\right)}^{2} \]
      10. +-commutative50.5%

        \[\leadsto {\left(\sqrt{e^{x} + \color{blue}{\left(e^{-x} + -2\right)}}\right)}^{2} \]
      11. associate-+r+50.4%

        \[\leadsto {\left(\sqrt{\color{blue}{\left(e^{x} + e^{-x}\right) + -2}}\right)}^{2} \]
      12. +-commutative50.4%

        \[\leadsto {\left(\sqrt{\color{blue}{-2 + \left(e^{x} + e^{-x}\right)}}\right)}^{2} \]
      13. cosh-undef50.4%

        \[\leadsto {\left(\sqrt{-2 + \color{blue}{2 \cdot \cosh x}}\right)}^{2} \]
    6. Applied egg-rr50.4%

      \[\leadsto \color{blue}{{\left(\sqrt{-2 + 2 \cdot \cosh x}\right)}^{2}} \]
    7. Taylor expanded in x around 0 99.9%

      \[\leadsto {\color{blue}{\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + 0.0005208333333333333 \cdot {x}^{2}\right)\right)\right)}}^{2} \]
    8. Step-by-step derivation
      1. *-commutative99.9%

        \[\leadsto {\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + \color{blue}{{x}^{2} \cdot 0.0005208333333333333}\right)\right)\right)}^{2} \]
    9. Simplified99.9%

      \[\leadsto {\color{blue}{\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot 0.0005208333333333333\right)\right)\right)}}^{2} \]

    if 1e-3 < (+.f64 (-.f64 (exp.f64 x) #s(literal 2 binary64)) (exp.f64 (neg.f64 x)))

    1. Initial program 99.5%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-99.5%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg99.5%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg99.5%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in99.5%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg99.5%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative99.5%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval99.5%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified99.5%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification99.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(e^{x} - 2\right) + e^{-x} \leq 0.001:\\ \;\;\;\;{\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot 0.0005208333333333333\right)\right)\right)}^{2}\\ \mathbf{else}:\\ \;\;\;\;e^{x} + \left(e^{-x} + -2\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 2: 99.9% accurate, 0.4× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(e^{x} - 2\right) + e^{-x}\\ \mathbf{if}\;t\_0 \leq 0.0008:\\ \;\;\;\;{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot 0.002777777777777778\right)\right)\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (+ (- (exp x) 2.0) (exp (- x)))))
   (if (<= t_0 0.0008)
     (*
      (pow x 2.0)
      (+
       1.0
       (*
        (pow x 2.0)
        (+ 0.08333333333333333 (* (pow x 2.0) 0.002777777777777778)))))
     t_0)))
double code(double x) {
	double t_0 = (exp(x) - 2.0) + exp(-x);
	double tmp;
	if (t_0 <= 0.0008) {
		tmp = pow(x, 2.0) * (1.0 + (pow(x, 2.0) * (0.08333333333333333 + (pow(x, 2.0) * 0.002777777777777778))));
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (exp(x) - 2.0d0) + exp(-x)
    if (t_0 <= 0.0008d0) then
        tmp = (x ** 2.0d0) * (1.0d0 + ((x ** 2.0d0) * (0.08333333333333333d0 + ((x ** 2.0d0) * 0.002777777777777778d0))))
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = (Math.exp(x) - 2.0) + Math.exp(-x);
	double tmp;
	if (t_0 <= 0.0008) {
		tmp = Math.pow(x, 2.0) * (1.0 + (Math.pow(x, 2.0) * (0.08333333333333333 + (Math.pow(x, 2.0) * 0.002777777777777778))));
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x):
	t_0 = (math.exp(x) - 2.0) + math.exp(-x)
	tmp = 0
	if t_0 <= 0.0008:
		tmp = math.pow(x, 2.0) * (1.0 + (math.pow(x, 2.0) * (0.08333333333333333 + (math.pow(x, 2.0) * 0.002777777777777778))))
	else:
		tmp = t_0
	return tmp
function code(x)
	t_0 = Float64(Float64(exp(x) - 2.0) + exp(Float64(-x)))
	tmp = 0.0
	if (t_0 <= 0.0008)
		tmp = Float64((x ^ 2.0) * Float64(1.0 + Float64((x ^ 2.0) * Float64(0.08333333333333333 + Float64((x ^ 2.0) * 0.002777777777777778)))));
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = (exp(x) - 2.0) + exp(-x);
	tmp = 0.0;
	if (t_0 <= 0.0008)
		tmp = (x ^ 2.0) * (1.0 + ((x ^ 2.0) * (0.08333333333333333 + ((x ^ 2.0) * 0.002777777777777778))));
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[(N[(N[Exp[x], $MachinePrecision] - 2.0), $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 0.0008], N[(N[Power[x, 2.0], $MachinePrecision] * N[(1.0 + N[(N[Power[x, 2.0], $MachinePrecision] * N[(0.08333333333333333 + N[(N[Power[x, 2.0], $MachinePrecision] * 0.002777777777777778), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], t$95$0]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(e^{x} - 2\right) + e^{-x}\\
\mathbf{if}\;t\_0 \leq 0.0008:\\
\;\;\;\;{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot 0.002777777777777778\right)\right)\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (-.f64 (exp.f64 x) #s(literal 2 binary64)) (exp.f64 (neg.f64 x))) < 8.00000000000000038e-4

    1. Initial program 50.4%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-50.3%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg50.3%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg50.3%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in50.3%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg50.3%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative50.3%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval50.3%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified50.3%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 99.9%

      \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + 0.002777777777777778 \cdot {x}^{2}\right)\right)} \]
    6. Step-by-step derivation
      1. *-commutative99.9%

        \[\leadsto {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + \color{blue}{{x}^{2} \cdot 0.002777777777777778}\right)\right) \]
    7. Simplified99.9%

      \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot 0.002777777777777778\right)\right)} \]

    if 8.00000000000000038e-4 < (+.f64 (-.f64 (exp.f64 x) #s(literal 2 binary64)) (exp.f64 (neg.f64 x)))

    1. Initial program 97.9%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification99.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(e^{x} - 2\right) + e^{-x} \leq 0.0008:\\ \;\;\;\;{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot 0.002777777777777778\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(e^{x} - 2\right) + e^{-x}\\ \end{array} \]
  5. Add Preprocessing

Alternative 3: 99.2% accurate, 0.5× speedup?

\[\begin{array}{l} \\ {\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot \left(0.0005208333333333333 + {x}^{2} \cdot 3.1001984126984127 \cdot 10^{-6}\right)\right)\right)\right)}^{2} \end{array} \]
(FPCore (x)
 :precision binary64
 (pow
  (*
   x
   (+
    1.0
    (*
     (pow x 2.0)
     (+
      0.041666666666666664
      (*
       (pow x 2.0)
       (+ 0.0005208333333333333 (* (pow x 2.0) 3.1001984126984127e-6)))))))
  2.0))
double code(double x) {
	return pow((x * (1.0 + (pow(x, 2.0) * (0.041666666666666664 + (pow(x, 2.0) * (0.0005208333333333333 + (pow(x, 2.0) * 3.1001984126984127e-6))))))), 2.0);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x * (1.0d0 + ((x ** 2.0d0) * (0.041666666666666664d0 + ((x ** 2.0d0) * (0.0005208333333333333d0 + ((x ** 2.0d0) * 3.1001984126984127d-6))))))) ** 2.0d0
end function
public static double code(double x) {
	return Math.pow((x * (1.0 + (Math.pow(x, 2.0) * (0.041666666666666664 + (Math.pow(x, 2.0) * (0.0005208333333333333 + (Math.pow(x, 2.0) * 3.1001984126984127e-6))))))), 2.0);
}
def code(x):
	return math.pow((x * (1.0 + (math.pow(x, 2.0) * (0.041666666666666664 + (math.pow(x, 2.0) * (0.0005208333333333333 + (math.pow(x, 2.0) * 3.1001984126984127e-6))))))), 2.0)
function code(x)
	return Float64(x * Float64(1.0 + Float64((x ^ 2.0) * Float64(0.041666666666666664 + Float64((x ^ 2.0) * Float64(0.0005208333333333333 + Float64((x ^ 2.0) * 3.1001984126984127e-6))))))) ^ 2.0
end
function tmp = code(x)
	tmp = (x * (1.0 + ((x ^ 2.0) * (0.041666666666666664 + ((x ^ 2.0) * (0.0005208333333333333 + ((x ^ 2.0) * 3.1001984126984127e-6))))))) ^ 2.0;
end
code[x_] := N[Power[N[(x * N[(1.0 + N[(N[Power[x, 2.0], $MachinePrecision] * N[(0.041666666666666664 + N[(N[Power[x, 2.0], $MachinePrecision] * N[(0.0005208333333333333 + N[(N[Power[x, 2.0], $MachinePrecision] * 3.1001984126984127e-6), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision]
\begin{array}{l}

\\
{\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot \left(0.0005208333333333333 + {x}^{2} \cdot 3.1001984126984127 \cdot 10^{-6}\right)\right)\right)\right)}^{2}
\end{array}
Derivation
  1. Initial program 51.7%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Step-by-step derivation
    1. associate-+l-51.6%

      \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
    2. sub-neg51.6%

      \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
    3. sub-neg51.6%

      \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
    4. distribute-neg-in51.6%

      \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
    5. remove-double-neg51.6%

      \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
    6. +-commutative51.6%

      \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
    7. metadata-eval51.6%

      \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
  3. Simplified51.6%

    \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
  4. Add Preprocessing
  5. Step-by-step derivation
    1. +-commutative51.6%

      \[\leadsto e^{x} + \color{blue}{\left(-2 + e^{-x}\right)} \]
    2. associate-+r+51.7%

      \[\leadsto \color{blue}{\left(e^{x} + -2\right) + e^{-x}} \]
    3. metadata-eval51.7%

      \[\leadsto \left(e^{x} + \color{blue}{\left(-2\right)}\right) + e^{-x} \]
    4. sub-neg51.7%

      \[\leadsto \color{blue}{\left(e^{x} - 2\right)} + e^{-x} \]
    5. add-sqr-sqrt51.6%

      \[\leadsto \color{blue}{\sqrt{\left(e^{x} - 2\right) + e^{-x}} \cdot \sqrt{\left(e^{x} - 2\right) + e^{-x}}} \]
    6. pow251.6%

      \[\leadsto \color{blue}{{\left(\sqrt{\left(e^{x} - 2\right) + e^{-x}}\right)}^{2}} \]
    7. sub-neg51.6%

      \[\leadsto {\left(\sqrt{\color{blue}{\left(e^{x} + \left(-2\right)\right)} + e^{-x}}\right)}^{2} \]
    8. metadata-eval51.6%

      \[\leadsto {\left(\sqrt{\left(e^{x} + \color{blue}{-2}\right) + e^{-x}}\right)}^{2} \]
    9. associate-+r+51.6%

      \[\leadsto {\left(\sqrt{\color{blue}{e^{x} + \left(-2 + e^{-x}\right)}}\right)}^{2} \]
    10. +-commutative51.6%

      \[\leadsto {\left(\sqrt{e^{x} + \color{blue}{\left(e^{-x} + -2\right)}}\right)}^{2} \]
    11. associate-+r+51.5%

      \[\leadsto {\left(\sqrt{\color{blue}{\left(e^{x} + e^{-x}\right) + -2}}\right)}^{2} \]
    12. +-commutative51.5%

      \[\leadsto {\left(\sqrt{\color{blue}{-2 + \left(e^{x} + e^{-x}\right)}}\right)}^{2} \]
    13. cosh-undef51.5%

      \[\leadsto {\left(\sqrt{-2 + \color{blue}{2 \cdot \cosh x}}\right)}^{2} \]
  6. Applied egg-rr51.5%

    \[\leadsto \color{blue}{{\left(\sqrt{-2 + 2 \cdot \cosh x}\right)}^{2}} \]
  7. Taylor expanded in x around 0 98.5%

    \[\leadsto {\color{blue}{\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot \left(0.0005208333333333333 + 3.1001984126984127 \cdot 10^{-6} \cdot {x}^{2}\right)\right)\right)\right)}}^{2} \]
  8. Step-by-step derivation
    1. *-commutative98.5%

      \[\leadsto {\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot \left(0.0005208333333333333 + \color{blue}{{x}^{2} \cdot 3.1001984126984127 \cdot 10^{-6}}\right)\right)\right)\right)}^{2} \]
  9. Simplified98.5%

    \[\leadsto {\color{blue}{\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot \left(0.0005208333333333333 + {x}^{2} \cdot 3.1001984126984127 \cdot 10^{-6}\right)\right)\right)\right)}}^{2} \]
  10. Final simplification98.5%

    \[\leadsto {\left(x \cdot \left(1 + {x}^{2} \cdot \left(0.041666666666666664 + {x}^{2} \cdot \left(0.0005208333333333333 + {x}^{2} \cdot 3.1001984126984127 \cdot 10^{-6}\right)\right)\right)\right)}^{2} \]
  11. Add Preprocessing

Alternative 4: 99.2% accurate, 0.5× speedup?

\[\begin{array}{l} \\ {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot \left(0.002777777777777778 + {x}^{2} \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right) \end{array} \]
(FPCore (x)
 :precision binary64
 (*
  (pow x 2.0)
  (+
   1.0
   (*
    (pow x 2.0)
    (+
     0.08333333333333333
     (*
      (pow x 2.0)
      (+ 0.002777777777777778 (* (pow x 2.0) 4.96031746031746e-5))))))))
double code(double x) {
	return pow(x, 2.0) * (1.0 + (pow(x, 2.0) * (0.08333333333333333 + (pow(x, 2.0) * (0.002777777777777778 + (pow(x, 2.0) * 4.96031746031746e-5))))));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (x ** 2.0d0) * (1.0d0 + ((x ** 2.0d0) * (0.08333333333333333d0 + ((x ** 2.0d0) * (0.002777777777777778d0 + ((x ** 2.0d0) * 4.96031746031746d-5))))))
end function
public static double code(double x) {
	return Math.pow(x, 2.0) * (1.0 + (Math.pow(x, 2.0) * (0.08333333333333333 + (Math.pow(x, 2.0) * (0.002777777777777778 + (Math.pow(x, 2.0) * 4.96031746031746e-5))))));
}
def code(x):
	return math.pow(x, 2.0) * (1.0 + (math.pow(x, 2.0) * (0.08333333333333333 + (math.pow(x, 2.0) * (0.002777777777777778 + (math.pow(x, 2.0) * 4.96031746031746e-5))))))
function code(x)
	return Float64((x ^ 2.0) * Float64(1.0 + Float64((x ^ 2.0) * Float64(0.08333333333333333 + Float64((x ^ 2.0) * Float64(0.002777777777777778 + Float64((x ^ 2.0) * 4.96031746031746e-5)))))))
end
function tmp = code(x)
	tmp = (x ^ 2.0) * (1.0 + ((x ^ 2.0) * (0.08333333333333333 + ((x ^ 2.0) * (0.002777777777777778 + ((x ^ 2.0) * 4.96031746031746e-5))))));
end
code[x_] := N[(N[Power[x, 2.0], $MachinePrecision] * N[(1.0 + N[(N[Power[x, 2.0], $MachinePrecision] * N[(0.08333333333333333 + N[(N[Power[x, 2.0], $MachinePrecision] * N[(0.002777777777777778 + N[(N[Power[x, 2.0], $MachinePrecision] * 4.96031746031746e-5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot \left(0.002777777777777778 + {x}^{2} \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)
\end{array}
Derivation
  1. Initial program 51.7%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Step-by-step derivation
    1. associate-+l-51.6%

      \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
    2. sub-neg51.6%

      \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
    3. sub-neg51.6%

      \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
    4. distribute-neg-in51.6%

      \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
    5. remove-double-neg51.6%

      \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
    6. +-commutative51.6%

      \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
    7. metadata-eval51.6%

      \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
  3. Simplified51.6%

    \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around 0 98.4%

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot \left(0.002777777777777778 + 4.96031746031746 \cdot 10^{-5} \cdot {x}^{2}\right)\right)\right)} \]
  6. Step-by-step derivation
    1. *-commutative98.4%

      \[\leadsto {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot \left(0.002777777777777778 + \color{blue}{{x}^{2} \cdot 4.96031746031746 \cdot 10^{-5}}\right)\right)\right) \]
  7. Simplified98.4%

    \[\leadsto \color{blue}{{x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot \left(0.002777777777777778 + {x}^{2} \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right)} \]
  8. Final simplification98.4%

    \[\leadsto {x}^{2} \cdot \left(1 + {x}^{2} \cdot \left(0.08333333333333333 + {x}^{2} \cdot \left(0.002777777777777778 + {x}^{2} \cdot 4.96031746031746 \cdot 10^{-5}\right)\right)\right) \]
  9. Add Preprocessing

Alternative 5: 99.8% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(e^{x} - 2\right) + e^{-x}\\ \mathbf{if}\;t\_0 \leq 5 \cdot 10^{-7}:\\ \;\;\;\;{\left(x + 0.041666666666666664 \cdot {x}^{3}\right)}^{2}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (+ (- (exp x) 2.0) (exp (- x)))))
   (if (<= t_0 5e-7)
     (pow (+ x (* 0.041666666666666664 (pow x 3.0))) 2.0)
     t_0)))
double code(double x) {
	double t_0 = (exp(x) - 2.0) + exp(-x);
	double tmp;
	if (t_0 <= 5e-7) {
		tmp = pow((x + (0.041666666666666664 * pow(x, 3.0))), 2.0);
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (exp(x) - 2.0d0) + exp(-x)
    if (t_0 <= 5d-7) then
        tmp = (x + (0.041666666666666664d0 * (x ** 3.0d0))) ** 2.0d0
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = (Math.exp(x) - 2.0) + Math.exp(-x);
	double tmp;
	if (t_0 <= 5e-7) {
		tmp = Math.pow((x + (0.041666666666666664 * Math.pow(x, 3.0))), 2.0);
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x):
	t_0 = (math.exp(x) - 2.0) + math.exp(-x)
	tmp = 0
	if t_0 <= 5e-7:
		tmp = math.pow((x + (0.041666666666666664 * math.pow(x, 3.0))), 2.0)
	else:
		tmp = t_0
	return tmp
function code(x)
	t_0 = Float64(Float64(exp(x) - 2.0) + exp(Float64(-x)))
	tmp = 0.0
	if (t_0 <= 5e-7)
		tmp = Float64(x + Float64(0.041666666666666664 * (x ^ 3.0))) ^ 2.0;
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = (exp(x) - 2.0) + exp(-x);
	tmp = 0.0;
	if (t_0 <= 5e-7)
		tmp = (x + (0.041666666666666664 * (x ^ 3.0))) ^ 2.0;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[(N[(N[Exp[x], $MachinePrecision] - 2.0), $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 5e-7], N[Power[N[(x + N[(0.041666666666666664 * N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], 2.0], $MachinePrecision], t$95$0]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(e^{x} - 2\right) + e^{-x}\\
\mathbf{if}\;t\_0 \leq 5 \cdot 10^{-7}:\\
\;\;\;\;{\left(x + 0.041666666666666664 \cdot {x}^{3}\right)}^{2}\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (-.f64 (exp.f64 x) #s(literal 2 binary64)) (exp.f64 (neg.f64 x))) < 4.99999999999999977e-7

    1. Initial program 50.2%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-50.2%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg50.2%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg50.2%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in50.2%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg50.2%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative50.2%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval50.2%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified50.2%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. +-commutative50.2%

        \[\leadsto e^{x} + \color{blue}{\left(-2 + e^{-x}\right)} \]
      2. associate-+r+50.2%

        \[\leadsto \color{blue}{\left(e^{x} + -2\right) + e^{-x}} \]
      3. metadata-eval50.2%

        \[\leadsto \left(e^{x} + \color{blue}{\left(-2\right)}\right) + e^{-x} \]
      4. sub-neg50.2%

        \[\leadsto \color{blue}{\left(e^{x} - 2\right)} + e^{-x} \]
      5. add-sqr-sqrt50.2%

        \[\leadsto \color{blue}{\sqrt{\left(e^{x} - 2\right) + e^{-x}} \cdot \sqrt{\left(e^{x} - 2\right) + e^{-x}}} \]
      6. pow250.2%

        \[\leadsto \color{blue}{{\left(\sqrt{\left(e^{x} - 2\right) + e^{-x}}\right)}^{2}} \]
      7. sub-neg50.2%

        \[\leadsto {\left(\sqrt{\color{blue}{\left(e^{x} + \left(-2\right)\right)} + e^{-x}}\right)}^{2} \]
      8. metadata-eval50.2%

        \[\leadsto {\left(\sqrt{\left(e^{x} + \color{blue}{-2}\right) + e^{-x}}\right)}^{2} \]
      9. associate-+r+50.2%

        \[\leadsto {\left(\sqrt{\color{blue}{e^{x} + \left(-2 + e^{-x}\right)}}\right)}^{2} \]
      10. +-commutative50.2%

        \[\leadsto {\left(\sqrt{e^{x} + \color{blue}{\left(e^{-x} + -2\right)}}\right)}^{2} \]
      11. associate-+r+50.1%

        \[\leadsto {\left(\sqrt{\color{blue}{\left(e^{x} + e^{-x}\right) + -2}}\right)}^{2} \]
      12. +-commutative50.1%

        \[\leadsto {\left(\sqrt{\color{blue}{-2 + \left(e^{x} + e^{-x}\right)}}\right)}^{2} \]
      13. cosh-undef50.1%

        \[\leadsto {\left(\sqrt{-2 + \color{blue}{2 \cdot \cosh x}}\right)}^{2} \]
    6. Applied egg-rr50.1%

      \[\leadsto \color{blue}{{\left(\sqrt{-2 + 2 \cdot \cosh x}\right)}^{2}} \]
    7. Taylor expanded in x around 0 100.0%

      \[\leadsto {\color{blue}{\left(x \cdot \left(1 + 0.041666666666666664 \cdot {x}^{2}\right)\right)}}^{2} \]
    8. Step-by-step derivation
      1. distribute-rgt-in100.0%

        \[\leadsto {\color{blue}{\left(1 \cdot x + \left(0.041666666666666664 \cdot {x}^{2}\right) \cdot x\right)}}^{2} \]
      2. *-lft-identity100.0%

        \[\leadsto {\left(\color{blue}{x} + \left(0.041666666666666664 \cdot {x}^{2}\right) \cdot x\right)}^{2} \]
      3. associate-*l*100.0%

        \[\leadsto {\left(x + \color{blue}{0.041666666666666664 \cdot \left({x}^{2} \cdot x\right)}\right)}^{2} \]
      4. unpow2100.0%

        \[\leadsto {\left(x + 0.041666666666666664 \cdot \left(\color{blue}{\left(x \cdot x\right)} \cdot x\right)\right)}^{2} \]
      5. unpow3100.0%

        \[\leadsto {\left(x + 0.041666666666666664 \cdot \color{blue}{{x}^{3}}\right)}^{2} \]
    9. Simplified100.0%

      \[\leadsto {\color{blue}{\left(x + 0.041666666666666664 \cdot {x}^{3}\right)}}^{2} \]

    if 4.99999999999999977e-7 < (+.f64 (-.f64 (exp.f64 x) #s(literal 2 binary64)) (exp.f64 (neg.f64 x)))

    1. Initial program 96.4%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification99.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(e^{x} - 2\right) + e^{-x} \leq 5 \cdot 10^{-7}:\\ \;\;\;\;{\left(x + 0.041666666666666664 \cdot {x}^{3}\right)}^{2}\\ \mathbf{else}:\\ \;\;\;\;\left(e^{x} - 2\right) + e^{-x}\\ \end{array} \]
  5. Add Preprocessing

Alternative 6: 99.6% accurate, 0.5× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(e^{x} - 2\right) + e^{-x}\\ \mathbf{if}\;t\_0 \leq 5 \cdot 10^{-9}:\\ \;\;\;\;{x}^{2}\\ \mathbf{else}:\\ \;\;\;\;t\_0\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (+ (- (exp x) 2.0) (exp (- x)))))
   (if (<= t_0 5e-9) (pow x 2.0) t_0)))
double code(double x) {
	double t_0 = (exp(x) - 2.0) + exp(-x);
	double tmp;
	if (t_0 <= 5e-9) {
		tmp = pow(x, 2.0);
	} else {
		tmp = t_0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (exp(x) - 2.0d0) + exp(-x)
    if (t_0 <= 5d-9) then
        tmp = x ** 2.0d0
    else
        tmp = t_0
    end if
    code = tmp
end function
public static double code(double x) {
	double t_0 = (Math.exp(x) - 2.0) + Math.exp(-x);
	double tmp;
	if (t_0 <= 5e-9) {
		tmp = Math.pow(x, 2.0);
	} else {
		tmp = t_0;
	}
	return tmp;
}
def code(x):
	t_0 = (math.exp(x) - 2.0) + math.exp(-x)
	tmp = 0
	if t_0 <= 5e-9:
		tmp = math.pow(x, 2.0)
	else:
		tmp = t_0
	return tmp
function code(x)
	t_0 = Float64(Float64(exp(x) - 2.0) + exp(Float64(-x)))
	tmp = 0.0
	if (t_0 <= 5e-9)
		tmp = x ^ 2.0;
	else
		tmp = t_0;
	end
	return tmp
end
function tmp_2 = code(x)
	t_0 = (exp(x) - 2.0) + exp(-x);
	tmp = 0.0;
	if (t_0 <= 5e-9)
		tmp = x ^ 2.0;
	else
		tmp = t_0;
	end
	tmp_2 = tmp;
end
code[x_] := Block[{t$95$0 = N[(N[(N[Exp[x], $MachinePrecision] - 2.0), $MachinePrecision] + N[Exp[(-x)], $MachinePrecision]), $MachinePrecision]}, If[LessEqual[t$95$0, 5e-9], N[Power[x, 2.0], $MachinePrecision], t$95$0]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(e^{x} - 2\right) + e^{-x}\\
\mathbf{if}\;t\_0 \leq 5 \cdot 10^{-9}:\\
\;\;\;\;{x}^{2}\\

\mathbf{else}:\\
\;\;\;\;t\_0\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if (+.f64 (-.f64 (exp.f64 x) #s(literal 2 binary64)) (exp.f64 (neg.f64 x))) < 5.0000000000000001e-9

    1. Initial program 50.0%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-50.0%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg50.0%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg50.0%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in50.0%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg50.0%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative50.0%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval50.0%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified50.0%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 99.7%

      \[\leadsto \color{blue}{{x}^{2}} \]

    if 5.0000000000000001e-9 < (+.f64 (-.f64 (exp.f64 x) #s(literal 2 binary64)) (exp.f64 (neg.f64 x)))

    1. Initial program 91.5%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification99.4%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\left(e^{x} - 2\right) + e^{-x} \leq 5 \cdot 10^{-9}:\\ \;\;\;\;{x}^{2}\\ \mathbf{else}:\\ \;\;\;\;\left(e^{x} - 2\right) + e^{-x}\\ \end{array} \]
  5. Add Preprocessing

Alternative 7: 99.1% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.00013:\\ \;\;\;\;{x}^{2}\\ \mathbf{else}:\\ \;\;\;\;e^{x} + \left(e^{-x} + -2\right)\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 0.00013) (pow x 2.0) (+ (exp x) (+ (exp (- x)) -2.0))))
double code(double x) {
	double tmp;
	if (x <= 0.00013) {
		tmp = pow(x, 2.0);
	} else {
		tmp = exp(x) + (exp(-x) + -2.0);
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 0.00013d0) then
        tmp = x ** 2.0d0
    else
        tmp = exp(x) + (exp(-x) + (-2.0d0))
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 0.00013) {
		tmp = Math.pow(x, 2.0);
	} else {
		tmp = Math.exp(x) + (Math.exp(-x) + -2.0);
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 0.00013:
		tmp = math.pow(x, 2.0)
	else:
		tmp = math.exp(x) + (math.exp(-x) + -2.0)
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 0.00013)
		tmp = x ^ 2.0;
	else
		tmp = Float64(exp(x) + Float64(exp(Float64(-x)) + -2.0));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 0.00013)
		tmp = x ^ 2.0;
	else
		tmp = exp(x) + (exp(-x) + -2.0);
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 0.00013], N[Power[x, 2.0], $MachinePrecision], N[(N[Exp[x], $MachinePrecision] + N[(N[Exp[(-x)], $MachinePrecision] + -2.0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.00013:\\
\;\;\;\;{x}^{2}\\

\mathbf{else}:\\
\;\;\;\;e^{x} + \left(e^{-x} + -2\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 1.29999999999999989e-4

    1. Initial program 50.3%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-50.3%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg50.3%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg50.3%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in50.3%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg50.3%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative50.3%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval50.3%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified50.3%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 99.2%

      \[\leadsto \color{blue}{{x}^{2}} \]

    if 1.29999999999999989e-4 < x

    1. Initial program 92.6%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-92.1%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg92.1%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg92.1%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in92.1%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg92.1%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative92.1%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval92.1%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified92.1%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
  3. Recombined 2 regimes into one program.
  4. Final simplification99.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.00013:\\ \;\;\;\;{x}^{2}\\ \mathbf{else}:\\ \;\;\;\;e^{x} + \left(e^{-x} + -2\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 8: 99.1% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.000215:\\ \;\;\;\;{x}^{2}\\ \mathbf{else}:\\ \;\;\;\;2 \cdot \cosh x - 2\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x 0.000215) (pow x 2.0) (- (* 2.0 (cosh x)) 2.0)))
double code(double x) {
	double tmp;
	if (x <= 0.000215) {
		tmp = pow(x, 2.0);
	} else {
		tmp = (2.0 * cosh(x)) - 2.0;
	}
	return tmp;
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: tmp
    if (x <= 0.000215d0) then
        tmp = x ** 2.0d0
    else
        tmp = (2.0d0 * cosh(x)) - 2.0d0
    end if
    code = tmp
end function
public static double code(double x) {
	double tmp;
	if (x <= 0.000215) {
		tmp = Math.pow(x, 2.0);
	} else {
		tmp = (2.0 * Math.cosh(x)) - 2.0;
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 0.000215:
		tmp = math.pow(x, 2.0)
	else:
		tmp = (2.0 * math.cosh(x)) - 2.0
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 0.000215)
		tmp = x ^ 2.0;
	else
		tmp = Float64(Float64(2.0 * cosh(x)) - 2.0);
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= 0.000215)
		tmp = x ^ 2.0;
	else
		tmp = (2.0 * cosh(x)) - 2.0;
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, 0.000215], N[Power[x, 2.0], $MachinePrecision], N[(N[(2.0 * N[Cosh[x], $MachinePrecision]), $MachinePrecision] - 2.0), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.000215:\\
\;\;\;\;{x}^{2}\\

\mathbf{else}:\\
\;\;\;\;2 \cdot \cosh x - 2\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 2.14999999999999995e-4

    1. Initial program 50.3%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-50.3%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg50.3%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg50.3%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in50.3%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg50.3%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative50.3%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval50.3%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified50.3%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 99.2%

      \[\leadsto \color{blue}{{x}^{2}} \]

    if 2.14999999999999995e-4 < x

    1. Initial program 92.6%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-92.1%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg92.1%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg92.1%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in92.1%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg92.1%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative92.1%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval92.1%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified92.1%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. +-commutative92.1%

        \[\leadsto e^{x} + \color{blue}{\left(-2 + e^{-x}\right)} \]
      2. associate-+r+92.6%

        \[\leadsto \color{blue}{\left(e^{x} + -2\right) + e^{-x}} \]
      3. metadata-eval92.6%

        \[\leadsto \left(e^{x} + \color{blue}{\left(-2\right)}\right) + e^{-x} \]
      4. sub-neg92.6%

        \[\leadsto \color{blue}{\left(e^{x} - 2\right)} + e^{-x} \]
      5. +-commutative92.6%

        \[\leadsto \color{blue}{e^{-x} + \left(e^{x} - 2\right)} \]
      6. associate-+r-91.8%

        \[\leadsto \color{blue}{\left(e^{-x} + e^{x}\right) - 2} \]
      7. +-commutative91.8%

        \[\leadsto \color{blue}{\left(e^{x} + e^{-x}\right)} - 2 \]
      8. cosh-undef91.8%

        \[\leadsto \color{blue}{2 \cdot \cosh x} - 2 \]
    6. Applied egg-rr91.8%

      \[\leadsto \color{blue}{2 \cdot \cosh x - 2} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.000215:\\ \;\;\;\;{x}^{2}\\ \mathbf{else}:\\ \;\;\;\;2 \cdot \cosh x - 2\\ \end{array} \]
  5. Add Preprocessing

Alternative 9: 52.4% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 2.25 \cdot 10^{-103}:\\ \;\;\;\;0\\ \mathbf{else}:\\ \;\;\;\;\mathsf{expm1}\left(x\right)\\ \end{array} \end{array} \]
(FPCore (x) :precision binary64 (if (<= x 2.25e-103) 0.0 (expm1 x)))
double code(double x) {
	double tmp;
	if (x <= 2.25e-103) {
		tmp = 0.0;
	} else {
		tmp = expm1(x);
	}
	return tmp;
}
public static double code(double x) {
	double tmp;
	if (x <= 2.25e-103) {
		tmp = 0.0;
	} else {
		tmp = Math.expm1(x);
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= 2.25e-103:
		tmp = 0.0
	else:
		tmp = math.expm1(x)
	return tmp
function code(x)
	tmp = 0.0
	if (x <= 2.25e-103)
		tmp = 0.0;
	else
		tmp = expm1(x);
	end
	return tmp
end
code[x_] := If[LessEqual[x, 2.25e-103], 0.0, N[(Exp[x] - 1), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 2.25 \cdot 10^{-103}:\\
\;\;\;\;0\\

\mathbf{else}:\\
\;\;\;\;\mathsf{expm1}\left(x\right)\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 2.25e-103

    1. Initial program 60.3%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-60.3%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg60.3%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg60.3%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in60.3%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg60.3%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative60.3%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval60.3%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified60.3%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
    5. Step-by-step derivation
      1. +-commutative60.3%

        \[\leadsto e^{x} + \color{blue}{\left(-2 + e^{-x}\right)} \]
      2. associate-+r+60.3%

        \[\leadsto \color{blue}{\left(e^{x} + -2\right) + e^{-x}} \]
      3. metadata-eval60.3%

        \[\leadsto \left(e^{x} + \color{blue}{\left(-2\right)}\right) + e^{-x} \]
      4. sub-neg60.3%

        \[\leadsto \color{blue}{\left(e^{x} - 2\right)} + e^{-x} \]
      5. add-log-exp59.8%

        \[\leadsto \color{blue}{\log \left(e^{\left(e^{x} - 2\right) + e^{-x}}\right)} \]
      6. +-commutative59.8%

        \[\leadsto \log \left(e^{\color{blue}{e^{-x} + \left(e^{x} - 2\right)}}\right) \]
      7. sub-neg59.8%

        \[\leadsto \log \left(e^{e^{-x} + \color{blue}{\left(e^{x} + \left(-2\right)\right)}}\right) \]
      8. metadata-eval59.8%

        \[\leadsto \log \left(e^{e^{-x} + \left(e^{x} + \color{blue}{-2}\right)}\right) \]
      9. associate-+r+59.7%

        \[\leadsto \log \left(e^{\color{blue}{\left(e^{-x} + e^{x}\right) + -2}}\right) \]
      10. +-commutative59.7%

        \[\leadsto \log \left(e^{\color{blue}{\left(e^{x} + e^{-x}\right)} + -2}\right) \]
      11. +-commutative59.7%

        \[\leadsto \log \left(e^{\color{blue}{-2 + \left(e^{x} + e^{-x}\right)}}\right) \]
      12. cosh-undef59.7%

        \[\leadsto \log \left(e^{-2 + \color{blue}{2 \cdot \cosh x}}\right) \]
    6. Applied egg-rr59.7%

      \[\leadsto \color{blue}{\log \left(e^{-2 + 2 \cdot \cosh x}\right)} \]
    7. Taylor expanded in x around 0 59.2%

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

    if 2.25e-103 < x

    1. Initial program 19.5%

      \[\left(e^{x} - 2\right) + e^{-x} \]
    2. Step-by-step derivation
      1. associate-+l-19.3%

        \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
      2. sub-neg19.3%

        \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
      3. sub-neg19.3%

        \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
      4. distribute-neg-in19.3%

        \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
      5. remove-double-neg19.3%

        \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
      6. +-commutative19.3%

        \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
      7. metadata-eval19.3%

        \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
    3. Simplified19.3%

      \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
    4. Add Preprocessing
    5. Taylor expanded in x around 0 8.3%

      \[\leadsto e^{x} + \color{blue}{-1} \]
    6. Taylor expanded in x around inf 8.3%

      \[\leadsto \color{blue}{e^{x} - 1} \]
    7. Step-by-step derivation
      1. expm1-define10.4%

        \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right)} \]
    8. Simplified10.4%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right)} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification48.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 2.25 \cdot 10^{-103}:\\ \;\;\;\;0\\ \mathbf{else}:\\ \;\;\;\;\mathsf{expm1}\left(x\right)\\ \end{array} \]
  5. Add Preprocessing

Alternative 10: 98.4% accurate, 2.0× speedup?

\[\begin{array}{l} \\ {x}^{2} \end{array} \]
(FPCore (x) :precision binary64 (pow x 2.0))
double code(double x) {
	return pow(x, 2.0);
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = x ** 2.0d0
end function
public static double code(double x) {
	return Math.pow(x, 2.0);
}
def code(x):
	return math.pow(x, 2.0)
function code(x)
	return x ^ 2.0
end
function tmp = code(x)
	tmp = x ^ 2.0;
end
code[x_] := N[Power[x, 2.0], $MachinePrecision]
\begin{array}{l}

\\
{x}^{2}
\end{array}
Derivation
  1. Initial program 51.7%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Step-by-step derivation
    1. associate-+l-51.6%

      \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
    2. sub-neg51.6%

      \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
    3. sub-neg51.6%

      \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
    4. distribute-neg-in51.6%

      \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
    5. remove-double-neg51.6%

      \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
    6. +-commutative51.6%

      \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
    7. metadata-eval51.6%

      \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
  3. Simplified51.6%

    \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around 0 97.0%

    \[\leadsto \color{blue}{{x}^{2}} \]
  6. Final simplification97.0%

    \[\leadsto {x}^{2} \]
  7. Add Preprocessing

Alternative 11: 6.2% accurate, 2.0× speedup?

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

\\
\mathsf{expm1}\left(x\right)
\end{array}
Derivation
  1. Initial program 51.7%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Step-by-step derivation
    1. associate-+l-51.6%

      \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
    2. sub-neg51.6%

      \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
    3. sub-neg51.6%

      \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
    4. distribute-neg-in51.6%

      \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
    5. remove-double-neg51.6%

      \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
    6. +-commutative51.6%

      \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
    7. metadata-eval51.6%

      \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
  3. Simplified51.6%

    \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around 0 48.5%

    \[\leadsto e^{x} + \color{blue}{-1} \]
  6. Taylor expanded in x around inf 48.5%

    \[\leadsto \color{blue}{e^{x} - 1} \]
  7. Step-by-step derivation
    1. expm1-define6.6%

      \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right)} \]
  8. Simplified6.6%

    \[\leadsto \color{blue}{\mathsf{expm1}\left(x\right)} \]
  9. Final simplification6.6%

    \[\leadsto \mathsf{expm1}\left(x\right) \]
  10. Add Preprocessing

Alternative 12: 5.9% accurate, 29.4× speedup?

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

\\
x \cdot \left(1 + x \cdot 0.5\right)
\end{array}
Derivation
  1. Initial program 51.7%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Step-by-step derivation
    1. associate-+l-51.6%

      \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
    2. sub-neg51.6%

      \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
    3. sub-neg51.6%

      \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
    4. distribute-neg-in51.6%

      \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
    5. remove-double-neg51.6%

      \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
    6. +-commutative51.6%

      \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
    7. metadata-eval51.6%

      \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
  3. Simplified51.6%

    \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around 0 48.5%

    \[\leadsto e^{x} + \color{blue}{-1} \]
  6. Taylor expanded in x around 0 6.3%

    \[\leadsto \color{blue}{x \cdot \left(1 + 0.5 \cdot x\right)} \]
  7. Step-by-step derivation
    1. *-commutative6.3%

      \[\leadsto x \cdot \left(1 + \color{blue}{x \cdot 0.5}\right) \]
  8. Simplified6.3%

    \[\leadsto \color{blue}{x \cdot \left(1 + x \cdot 0.5\right)} \]
  9. Final simplification6.3%

    \[\leadsto x \cdot \left(1 + x \cdot 0.5\right) \]
  10. Add Preprocessing

Alternative 13: 5.9% accurate, 206.0× speedup?

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

\\
x
\end{array}
Derivation
  1. Initial program 51.7%

    \[\left(e^{x} - 2\right) + e^{-x} \]
  2. Step-by-step derivation
    1. associate-+l-51.6%

      \[\leadsto \color{blue}{e^{x} - \left(2 - e^{-x}\right)} \]
    2. sub-neg51.6%

      \[\leadsto \color{blue}{e^{x} + \left(-\left(2 - e^{-x}\right)\right)} \]
    3. sub-neg51.6%

      \[\leadsto e^{x} + \left(-\color{blue}{\left(2 + \left(-e^{-x}\right)\right)}\right) \]
    4. distribute-neg-in51.6%

      \[\leadsto e^{x} + \color{blue}{\left(\left(-2\right) + \left(-\left(-e^{-x}\right)\right)\right)} \]
    5. remove-double-neg51.6%

      \[\leadsto e^{x} + \left(\left(-2\right) + \color{blue}{e^{-x}}\right) \]
    6. +-commutative51.6%

      \[\leadsto e^{x} + \color{blue}{\left(e^{-x} + \left(-2\right)\right)} \]
    7. metadata-eval51.6%

      \[\leadsto e^{x} + \left(e^{-x} + \color{blue}{-2}\right) \]
  3. Simplified51.6%

    \[\leadsto \color{blue}{e^{x} + \left(e^{-x} + -2\right)} \]
  4. Add Preprocessing
  5. Taylor expanded in x around 0 48.5%

    \[\leadsto e^{x} + \color{blue}{-1} \]
  6. Taylor expanded in x around 0 6.3%

    \[\leadsto \color{blue}{x} \]
  7. Final simplification6.3%

    \[\leadsto x \]
  8. Add Preprocessing

Developer target: 99.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \sinh \left(\frac{x}{2}\right)\\ 4 \cdot \left(t\_0 \cdot t\_0\right) \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (sinh (/ x 2.0)))) (* 4.0 (* t_0 t_0))))
double code(double x) {
	double t_0 = sinh((x / 2.0));
	return 4.0 * (t_0 * t_0);
}
real(8) function code(x)
    real(8), intent (in) :: x
    real(8) :: t_0
    t_0 = sinh((x / 2.0d0))
    code = 4.0d0 * (t_0 * t_0)
end function
public static double code(double x) {
	double t_0 = Math.sinh((x / 2.0));
	return 4.0 * (t_0 * t_0);
}
def code(x):
	t_0 = math.sinh((x / 2.0))
	return 4.0 * (t_0 * t_0)
function code(x)
	t_0 = sinh(Float64(x / 2.0))
	return Float64(4.0 * Float64(t_0 * t_0))
end
function tmp = code(x)
	t_0 = sinh((x / 2.0));
	tmp = 4.0 * (t_0 * t_0);
end
code[x_] := Block[{t$95$0 = N[Sinh[N[(x / 2.0), $MachinePrecision]], $MachinePrecision]}, N[(4.0 * N[(t$95$0 * t$95$0), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \sinh \left(\frac{x}{2}\right)\\
4 \cdot \left(t\_0 \cdot t\_0\right)
\end{array}
\end{array}

Reproduce

?
herbie shell --seed 2024077 
(FPCore (x)
  :name "exp2 (problem 3.3.7)"
  :precision binary64
  :pre (<= (fabs x) 710.0)

  :alt
  (* 4.0 (* (sinh (/ x 2.0)) (sinh (/ x 2.0))))

  (+ (- (exp x) 2.0) (exp (- x))))