Jmat.Real.erfi, branch x less than or equal to 0.5

Percentage Accurate: 99.9% → 99.8%
Time: 8.8s
Alternatives: 11
Speedup: N/A×

Specification

?
\[x \leq 0.5\]
\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\\ t_1 := \left(t_0 \cdot \left|x\right|\right) \cdot \left|x\right|\\ \left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot t_0\right) + \frac{1}{5} \cdot t_1\right) + \frac{1}{21} \cdot \left(\left(t_1 \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (* (* (fabs x) (fabs x)) (fabs x)))
        (t_1 (* (* t_0 (fabs x)) (fabs x))))
   (fabs
    (*
     (/ 1.0 (sqrt PI))
     (+
      (+ (+ (* 2.0 (fabs x)) (* (/ 2.0 3.0) t_0)) (* (/ 1.0 5.0) t_1))
      (* (/ 1.0 21.0) (* (* t_1 (fabs x)) (fabs x))))))))
double code(double x) {
	double t_0 = (fabs(x) * fabs(x)) * fabs(x);
	double t_1 = (t_0 * fabs(x)) * fabs(x);
	return fabs(((1.0 / sqrt(((double) M_PI))) * ((((2.0 * fabs(x)) + ((2.0 / 3.0) * t_0)) + ((1.0 / 5.0) * t_1)) + ((1.0 / 21.0) * ((t_1 * fabs(x)) * fabs(x))))));
}
public static double code(double x) {
	double t_0 = (Math.abs(x) * Math.abs(x)) * Math.abs(x);
	double t_1 = (t_0 * Math.abs(x)) * Math.abs(x);
	return Math.abs(((1.0 / Math.sqrt(Math.PI)) * ((((2.0 * Math.abs(x)) + ((2.0 / 3.0) * t_0)) + ((1.0 / 5.0) * t_1)) + ((1.0 / 21.0) * ((t_1 * Math.abs(x)) * Math.abs(x))))));
}
def code(x):
	t_0 = (math.fabs(x) * math.fabs(x)) * math.fabs(x)
	t_1 = (t_0 * math.fabs(x)) * math.fabs(x)
	return math.fabs(((1.0 / math.sqrt(math.pi)) * ((((2.0 * math.fabs(x)) + ((2.0 / 3.0) * t_0)) + ((1.0 / 5.0) * t_1)) + ((1.0 / 21.0) * ((t_1 * math.fabs(x)) * math.fabs(x))))))
function code(x)
	t_0 = Float64(Float64(abs(x) * abs(x)) * abs(x))
	t_1 = Float64(Float64(t_0 * abs(x)) * abs(x))
	return abs(Float64(Float64(1.0 / sqrt(pi)) * Float64(Float64(Float64(Float64(2.0 * abs(x)) + Float64(Float64(2.0 / 3.0) * t_0)) + Float64(Float64(1.0 / 5.0) * t_1)) + Float64(Float64(1.0 / 21.0) * Float64(Float64(t_1 * abs(x)) * abs(x))))))
end
function tmp = code(x)
	t_0 = (abs(x) * abs(x)) * abs(x);
	t_1 = (t_0 * abs(x)) * abs(x);
	tmp = abs(((1.0 / sqrt(pi)) * ((((2.0 * abs(x)) + ((2.0 / 3.0) * t_0)) + ((1.0 / 5.0) * t_1)) + ((1.0 / 21.0) * ((t_1 * abs(x)) * abs(x))))));
end
code[x_] := Block[{t$95$0 = N[(N[(N[Abs[x], $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(t$95$0 * N[Abs[x], $MachinePrecision]), $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision]}, N[Abs[N[(N[(1.0 / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision] * N[(N[(N[(N[(2.0 * N[Abs[x], $MachinePrecision]), $MachinePrecision] + N[(N[(2.0 / 3.0), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision] + N[(N[(1.0 / 5.0), $MachinePrecision] * t$95$1), $MachinePrecision]), $MachinePrecision] + N[(N[(1.0 / 21.0), $MachinePrecision] * N[(N[(t$95$1 * N[Abs[x], $MachinePrecision]), $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\\
t_1 := \left(t_0 \cdot \left|x\right|\right) \cdot \left|x\right|\\
\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot t_0\right) + \frac{1}{5} \cdot t_1\right) + \frac{1}{21} \cdot \left(\left(t_1 \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right|
\end{array}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 11 alternatives:

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

Initial Program: 99.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\\ t_1 := \left(t_0 \cdot \left|x\right|\right) \cdot \left|x\right|\\ \left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot t_0\right) + \frac{1}{5} \cdot t_1\right) + \frac{1}{21} \cdot \left(\left(t_1 \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (* (* (fabs x) (fabs x)) (fabs x)))
        (t_1 (* (* t_0 (fabs x)) (fabs x))))
   (fabs
    (*
     (/ 1.0 (sqrt PI))
     (+
      (+ (+ (* 2.0 (fabs x)) (* (/ 2.0 3.0) t_0)) (* (/ 1.0 5.0) t_1))
      (* (/ 1.0 21.0) (* (* t_1 (fabs x)) (fabs x))))))))
double code(double x) {
	double t_0 = (fabs(x) * fabs(x)) * fabs(x);
	double t_1 = (t_0 * fabs(x)) * fabs(x);
	return fabs(((1.0 / sqrt(((double) M_PI))) * ((((2.0 * fabs(x)) + ((2.0 / 3.0) * t_0)) + ((1.0 / 5.0) * t_1)) + ((1.0 / 21.0) * ((t_1 * fabs(x)) * fabs(x))))));
}
public static double code(double x) {
	double t_0 = (Math.abs(x) * Math.abs(x)) * Math.abs(x);
	double t_1 = (t_0 * Math.abs(x)) * Math.abs(x);
	return Math.abs(((1.0 / Math.sqrt(Math.PI)) * ((((2.0 * Math.abs(x)) + ((2.0 / 3.0) * t_0)) + ((1.0 / 5.0) * t_1)) + ((1.0 / 21.0) * ((t_1 * Math.abs(x)) * Math.abs(x))))));
}
def code(x):
	t_0 = (math.fabs(x) * math.fabs(x)) * math.fabs(x)
	t_1 = (t_0 * math.fabs(x)) * math.fabs(x)
	return math.fabs(((1.0 / math.sqrt(math.pi)) * ((((2.0 * math.fabs(x)) + ((2.0 / 3.0) * t_0)) + ((1.0 / 5.0) * t_1)) + ((1.0 / 21.0) * ((t_1 * math.fabs(x)) * math.fabs(x))))))
function code(x)
	t_0 = Float64(Float64(abs(x) * abs(x)) * abs(x))
	t_1 = Float64(Float64(t_0 * abs(x)) * abs(x))
	return abs(Float64(Float64(1.0 / sqrt(pi)) * Float64(Float64(Float64(Float64(2.0 * abs(x)) + Float64(Float64(2.0 / 3.0) * t_0)) + Float64(Float64(1.0 / 5.0) * t_1)) + Float64(Float64(1.0 / 21.0) * Float64(Float64(t_1 * abs(x)) * abs(x))))))
end
function tmp = code(x)
	t_0 = (abs(x) * abs(x)) * abs(x);
	t_1 = (t_0 * abs(x)) * abs(x);
	tmp = abs(((1.0 / sqrt(pi)) * ((((2.0 * abs(x)) + ((2.0 / 3.0) * t_0)) + ((1.0 / 5.0) * t_1)) + ((1.0 / 21.0) * ((t_1 * abs(x)) * abs(x))))));
end
code[x_] := Block[{t$95$0 = N[(N[(N[Abs[x], $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(t$95$0 * N[Abs[x], $MachinePrecision]), $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision]}, N[Abs[N[(N[(1.0 / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision] * N[(N[(N[(N[(2.0 * N[Abs[x], $MachinePrecision]), $MachinePrecision] + N[(N[(2.0 / 3.0), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision] + N[(N[(1.0 / 5.0), $MachinePrecision] * t$95$1), $MachinePrecision]), $MachinePrecision] + N[(N[(1.0 / 21.0), $MachinePrecision] * N[(N[(t$95$1 * N[Abs[x], $MachinePrecision]), $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\\
t_1 := \left(t_0 \cdot \left|x\right|\right) \cdot \left|x\right|\\
\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot t_0\right) + \frac{1}{5} \cdot t_1\right) + \frac{1}{21} \cdot \left(\left(t_1 \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right|
\end{array}
\end{array}

Alternative 1: 99.8% accurate, 2.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(x \cdot x\right) \cdot \left(x \cdot x\right)\\ \left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\mathsf{fma}\left(2, \left|x\right|, 0.6666666666666666 \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right) + 0.2 \cdot \left(\left|x\right| \cdot t_0\right)\right) + 0.047619047619047616 \cdot \left(\left|x\right| \cdot \left(\left(x \cdot x\right) \cdot t_0\right)\right)\right)\right| \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (let* ((t_0 (* (* x x) (* x x))))
   (fabs
    (*
     (/ 1.0 (sqrt PI))
     (+
      (+
       (fma 2.0 (fabs x) (* 0.6666666666666666 (* (fabs x) (* x x))))
       (* 0.2 (* (fabs x) t_0)))
      (* 0.047619047619047616 (* (fabs x) (* (* x x) t_0))))))))
double code(double x) {
	double t_0 = (x * x) * (x * x);
	return fabs(((1.0 / sqrt(((double) M_PI))) * ((fma(2.0, fabs(x), (0.6666666666666666 * (fabs(x) * (x * x)))) + (0.2 * (fabs(x) * t_0))) + (0.047619047619047616 * (fabs(x) * ((x * x) * t_0))))));
}
function code(x)
	t_0 = Float64(Float64(x * x) * Float64(x * x))
	return abs(Float64(Float64(1.0 / sqrt(pi)) * Float64(Float64(fma(2.0, abs(x), Float64(0.6666666666666666 * Float64(abs(x) * Float64(x * x)))) + Float64(0.2 * Float64(abs(x) * t_0))) + Float64(0.047619047619047616 * Float64(abs(x) * Float64(Float64(x * x) * t_0))))))
end
code[x_] := Block[{t$95$0 = N[(N[(x * x), $MachinePrecision] * N[(x * x), $MachinePrecision]), $MachinePrecision]}, N[Abs[N[(N[(1.0 / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision] * N[(N[(N[(2.0 * N[Abs[x], $MachinePrecision] + N[(0.6666666666666666 * N[(N[Abs[x], $MachinePrecision] * N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(0.2 * N[(N[Abs[x], $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(0.047619047619047616 * N[(N[Abs[x], $MachinePrecision] * N[(N[(x * x), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \left(x \cdot x\right) \cdot \left(x \cdot x\right)\\
\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\mathsf{fma}\left(2, \left|x\right|, 0.6666666666666666 \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right) + 0.2 \cdot \left(\left|x\right| \cdot t_0\right)\right) + 0.047619047619047616 \cdot \left(\left|x\right| \cdot \left(\left(x \cdot x\right) \cdot t_0\right)\right)\right)\right|
\end{array}
\end{array}
Derivation
  1. Initial program 99.9%

    \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
  2. Step-by-step derivation
    1. *-rgt-identity99.9%

      \[\leadsto \left|\color{blue}{\left(\frac{1}{\sqrt{\pi}} \cdot 1\right)} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
  3. Simplified99.9%

    \[\leadsto \color{blue}{\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\mathsf{fma}\left(2, \left|x\right|, 0.6666666666666666 \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right) + 0.2 \cdot \left(\left|x\right| \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right)\right) + 0.047619047619047616 \cdot \left(\left|x\right| \cdot \left(\left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right) \cdot \left(x \cdot x\right)\right)\right)\right)\right|} \]
  4. Final simplification99.9%

    \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\mathsf{fma}\left(2, \left|x\right|, 0.6666666666666666 \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right) + 0.2 \cdot \left(\left|x\right| \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right)\right) + 0.047619047619047616 \cdot \left(\left|x\right| \cdot \left(\left(x \cdot x\right) \cdot \left(\left(x \cdot x\right) \cdot \left(x \cdot x\right)\right)\right)\right)\right)\right| \]

Alternative 2: 99.2% accurate, 3.8× speedup?

\[\begin{array}{l} \\ \left|\left(x \cdot {\pi}^{-0.5}\right) \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \end{array} \]
(FPCore (x)
 :precision binary64
 (fabs
  (*
   (* x (pow PI -0.5))
   (+
    (fma 0.6666666666666666 (* x x) 2.0)
    (* 0.047619047619047616 (pow x 6.0))))))
double code(double x) {
	return fabs(((x * pow(((double) M_PI), -0.5)) * (fma(0.6666666666666666, (x * x), 2.0) + (0.047619047619047616 * pow(x, 6.0)))));
}
function code(x)
	return abs(Float64(Float64(x * (pi ^ -0.5)) * Float64(fma(0.6666666666666666, Float64(x * x), 2.0) + Float64(0.047619047619047616 * (x ^ 6.0)))))
end
code[x_] := N[Abs[N[(N[(x * N[Power[Pi, -0.5], $MachinePrecision]), $MachinePrecision] * N[(N[(0.6666666666666666 * N[(x * x), $MachinePrecision] + 2.0), $MachinePrecision] + N[(0.047619047619047616 * N[Power[x, 6.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|\left(x \cdot {\pi}^{-0.5}\right) \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right|
\end{array}
Derivation
  1. Initial program 99.9%

    \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
  2. Step-by-step derivation
    1. associate-*l/99.4%

      \[\leadsto \left|\color{blue}{\frac{1 \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)}{\sqrt{\pi}}}\right| \]
  3. Simplified99.4%

    \[\leadsto \color{blue}{\left|\frac{\left|x\right|}{\sqrt{\pi}} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {x}^{4}, 0.047619047619047616 \cdot {x}^{6}\right)\right)\right|} \]
  4. Taylor expanded in x around inf 99.3%

    \[\leadsto \left|\frac{\left|x\right|}{\sqrt{\pi}} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \color{blue}{0.047619047619047616 \cdot {x}^{6}}\right)\right| \]
  5. Step-by-step derivation
    1. div-inv99.8%

      \[\leadsto \left|\color{blue}{\left(\left|x\right| \cdot \frac{1}{\sqrt{\pi}}\right)} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    2. add-sqr-sqrt37.6%

      \[\leadsto \left|\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \frac{1}{\sqrt{\pi}}\right) \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    3. fabs-sqr37.6%

      \[\leadsto \left|\left(\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \frac{1}{\sqrt{\pi}}\right) \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    4. add-sqr-sqrt99.8%

      \[\leadsto \left|\left(\color{blue}{x} \cdot \frac{1}{\sqrt{\pi}}\right) \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    5. pow1/299.8%

      \[\leadsto \left|\left(x \cdot \frac{1}{\color{blue}{{\pi}^{0.5}}}\right) \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    6. pow-flip99.8%

      \[\leadsto \left|\left(x \cdot \color{blue}{{\pi}^{\left(-0.5\right)}}\right) \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    7. metadata-eval99.8%

      \[\leadsto \left|\left(x \cdot {\pi}^{\color{blue}{-0.5}}\right) \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  6. Applied egg-rr99.8%

    \[\leadsto \left|\color{blue}{\left(x \cdot {\pi}^{-0.5}\right)} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  7. Final simplification99.8%

    \[\leadsto \left|\left(x \cdot {\pi}^{-0.5}\right) \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]

Alternative 3: 98.8% accurate, 3.8× speedup?

\[\begin{array}{l} \\ \left|\left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right) \cdot \frac{x}{\sqrt{\pi}}\right| \end{array} \]
(FPCore (x)
 :precision binary64
 (fabs
  (*
   (+
    (fma 0.6666666666666666 (* x x) 2.0)
    (* 0.047619047619047616 (pow x 6.0)))
   (/ x (sqrt PI)))))
double code(double x) {
	return fabs(((fma(0.6666666666666666, (x * x), 2.0) + (0.047619047619047616 * pow(x, 6.0))) * (x / sqrt(((double) M_PI)))));
}
function code(x)
	return abs(Float64(Float64(fma(0.6666666666666666, Float64(x * x), 2.0) + Float64(0.047619047619047616 * (x ^ 6.0))) * Float64(x / sqrt(pi))))
end
code[x_] := N[Abs[N[(N[(N[(0.6666666666666666 * N[(x * x), $MachinePrecision] + 2.0), $MachinePrecision] + N[(0.047619047619047616 * N[Power[x, 6.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(x / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|\left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right) \cdot \frac{x}{\sqrt{\pi}}\right|
\end{array}
Derivation
  1. Initial program 99.9%

    \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
  2. Step-by-step derivation
    1. associate-*l/99.4%

      \[\leadsto \left|\color{blue}{\frac{1 \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)}{\sqrt{\pi}}}\right| \]
  3. Simplified99.4%

    \[\leadsto \color{blue}{\left|\frac{\left|x\right|}{\sqrt{\pi}} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {x}^{4}, 0.047619047619047616 \cdot {x}^{6}\right)\right)\right|} \]
  4. Taylor expanded in x around inf 99.3%

    \[\leadsto \left|\frac{\left|x\right|}{\sqrt{\pi}} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \color{blue}{0.047619047619047616 \cdot {x}^{6}}\right)\right| \]
  5. Step-by-step derivation
    1. expm1-log1p-u99.1%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\left|x\right|}{\sqrt{\pi}}\right)\right)} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    2. expm1-udef38.1%

      \[\leadsto \left|\color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\left|x\right|}{\sqrt{\pi}}\right)} - 1\right)} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    3. add-sqr-sqrt2.8%

      \[\leadsto \left|\left(e^{\mathsf{log1p}\left(\frac{\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|}{\sqrt{\pi}}\right)} - 1\right) \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    4. fabs-sqr2.8%

      \[\leadsto \left|\left(e^{\mathsf{log1p}\left(\frac{\color{blue}{\sqrt{x} \cdot \sqrt{x}}}{\sqrt{\pi}}\right)} - 1\right) \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    5. add-sqr-sqrt5.6%

      \[\leadsto \left|\left(e^{\mathsf{log1p}\left(\frac{\color{blue}{x}}{\sqrt{\pi}}\right)} - 1\right) \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  6. Applied egg-rr5.6%

    \[\leadsto \left|\color{blue}{\left(e^{\mathsf{log1p}\left(\frac{x}{\sqrt{\pi}}\right)} - 1\right)} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  7. Step-by-step derivation
    1. expm1-def66.5%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{x}{\sqrt{\pi}}\right)\right)} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    2. expm1-log1p99.1%

      \[\leadsto \left|\color{blue}{\frac{x}{\sqrt{\pi}}} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  8. Simplified99.3%

    \[\leadsto \left|\color{blue}{\frac{x}{\sqrt{\pi}}} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  9. Final simplification99.3%

    \[\leadsto \left|\left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + 0.047619047619047616 \cdot {x}^{6}\right) \cdot \frac{x}{\sqrt{\pi}}\right| \]

Alternative 4: 98.4% accurate, 4.8× speedup?

\[\begin{array}{l} \\ \left|\frac{x}{\sqrt{\pi}} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \end{array} \]
(FPCore (x)
 :precision binary64
 (fabs (* (/ x (sqrt PI)) (+ 2.0 (* 0.047619047619047616 (pow x 6.0))))))
double code(double x) {
	return fabs(((x / sqrt(((double) M_PI))) * (2.0 + (0.047619047619047616 * pow(x, 6.0)))));
}
public static double code(double x) {
	return Math.abs(((x / Math.sqrt(Math.PI)) * (2.0 + (0.047619047619047616 * Math.pow(x, 6.0)))));
}
def code(x):
	return math.fabs(((x / math.sqrt(math.pi)) * (2.0 + (0.047619047619047616 * math.pow(x, 6.0)))))
function code(x)
	return abs(Float64(Float64(x / sqrt(pi)) * Float64(2.0 + Float64(0.047619047619047616 * (x ^ 6.0)))))
end
function tmp = code(x)
	tmp = abs(((x / sqrt(pi)) * (2.0 + (0.047619047619047616 * (x ^ 6.0)))));
end
code[x_] := N[Abs[N[(N[(x / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision] * N[(2.0 + N[(0.047619047619047616 * N[Power[x, 6.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|\frac{x}{\sqrt{\pi}} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right|
\end{array}
Derivation
  1. Initial program 99.9%

    \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
  2. Step-by-step derivation
    1. associate-*l/99.4%

      \[\leadsto \left|\color{blue}{\frac{1 \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)}{\sqrt{\pi}}}\right| \]
  3. Simplified99.4%

    \[\leadsto \color{blue}{\left|\frac{\left|x\right|}{\sqrt{\pi}} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {x}^{4}, 0.047619047619047616 \cdot {x}^{6}\right)\right)\right|} \]
  4. Taylor expanded in x around inf 99.3%

    \[\leadsto \left|\frac{\left|x\right|}{\sqrt{\pi}} \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \color{blue}{0.047619047619047616 \cdot {x}^{6}}\right)\right| \]
  5. Taylor expanded in x around 0 99.1%

    \[\leadsto \left|\frac{\left|x\right|}{\sqrt{\pi}} \cdot \left(\color{blue}{2} + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  6. Step-by-step derivation
    1. expm1-log1p-u99.1%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\left|x\right|}{\sqrt{\pi}}\right)\right)} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    2. expm1-udef38.1%

      \[\leadsto \left|\color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\left|x\right|}{\sqrt{\pi}}\right)} - 1\right)} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    3. add-sqr-sqrt2.8%

      \[\leadsto \left|\left(e^{\mathsf{log1p}\left(\frac{\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|}{\sqrt{\pi}}\right)} - 1\right) \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    4. fabs-sqr2.8%

      \[\leadsto \left|\left(e^{\mathsf{log1p}\left(\frac{\color{blue}{\sqrt{x} \cdot \sqrt{x}}}{\sqrt{\pi}}\right)} - 1\right) \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    5. add-sqr-sqrt5.6%

      \[\leadsto \left|\left(e^{\mathsf{log1p}\left(\frac{\color{blue}{x}}{\sqrt{\pi}}\right)} - 1\right) \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  7. Applied egg-rr5.6%

    \[\leadsto \left|\color{blue}{\left(e^{\mathsf{log1p}\left(\frac{x}{\sqrt{\pi}}\right)} - 1\right)} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  8. Step-by-step derivation
    1. expm1-def66.5%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{x}{\sqrt{\pi}}\right)\right)} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
    2. expm1-log1p99.1%

      \[\leadsto \left|\color{blue}{\frac{x}{\sqrt{\pi}}} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  9. Simplified99.1%

    \[\leadsto \left|\color{blue}{\frac{x}{\sqrt{\pi}}} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]
  10. Final simplification99.1%

    \[\leadsto \left|\frac{x}{\sqrt{\pi}} \cdot \left(2 + 0.047619047619047616 \cdot {x}^{6}\right)\right| \]

Alternative 5: 98.9% accurate, 4.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.85:\\ \;\;\;\;\left|0.047619047619047616 \cdot \left({\pi}^{-0.5} \cdot {x}^{7}\right)\right|\\ \mathbf{else}:\\ \;\;\;\;\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -1.85)
   (fabs (* 0.047619047619047616 (* (pow PI -0.5) (pow x 7.0))))
   (fabs (* (pow PI -0.5) (+ x x)))))
double code(double x) {
	double tmp;
	if (x <= -1.85) {
		tmp = fabs((0.047619047619047616 * (pow(((double) M_PI), -0.5) * pow(x, 7.0))));
	} else {
		tmp = fabs((pow(((double) M_PI), -0.5) * (x + x)));
	}
	return tmp;
}
public static double code(double x) {
	double tmp;
	if (x <= -1.85) {
		tmp = Math.abs((0.047619047619047616 * (Math.pow(Math.PI, -0.5) * Math.pow(x, 7.0))));
	} else {
		tmp = Math.abs((Math.pow(Math.PI, -0.5) * (x + x)));
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= -1.85:
		tmp = math.fabs((0.047619047619047616 * (math.pow(math.pi, -0.5) * math.pow(x, 7.0))))
	else:
		tmp = math.fabs((math.pow(math.pi, -0.5) * (x + x)))
	return tmp
function code(x)
	tmp = 0.0
	if (x <= -1.85)
		tmp = abs(Float64(0.047619047619047616 * Float64((pi ^ -0.5) * (x ^ 7.0))));
	else
		tmp = abs(Float64((pi ^ -0.5) * Float64(x + x)));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= -1.85)
		tmp = abs((0.047619047619047616 * ((pi ^ -0.5) * (x ^ 7.0))));
	else
		tmp = abs(((pi ^ -0.5) * (x + x)));
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, -1.85], N[Abs[N[(0.047619047619047616 * N[(N[Power[Pi, -0.5], $MachinePrecision] * N[Power[x, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[Abs[N[(N[Power[Pi, -0.5], $MachinePrecision] * N[(x + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.85:\\
\;\;\;\;\left|0.047619047619047616 \cdot \left({\pi}^{-0.5} \cdot {x}^{7}\right)\right|\\

\mathbf{else}:\\
\;\;\;\;\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -1.8500000000000001

    1. Initial program 99.9%

      \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
    2. Step-by-step derivation
      1. associate-+l+99.9%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
      2. +-commutative99.9%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
    4. Taylor expanded in x around 0 100.0%

      \[\leadsto \left|\color{blue}{\left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \left|x\right|\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
    5. Step-by-step derivation
      1. *-commutative100.0%

        \[\leadsto \left|\color{blue}{\left(\left|x\right| \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)} \cdot \sqrt{\frac{1}{\pi}}\right| \]
      2. associate-*l*99.9%

        \[\leadsto \left|\color{blue}{\left|x\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
      3. rem-square-sqrt0.0%

        \[\leadsto \left|\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      4. fabs-sqr0.0%

        \[\leadsto \left|\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      5. rem-square-sqrt99.9%

        \[\leadsto \left|\color{blue}{x} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      6. *-commutative99.9%

        \[\leadsto \left|x \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)}\right| \]
      7. +-commutative99.9%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right) + 2\right)}\right)\right| \]
      8. associate-+l+99.9%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)}\right)\right| \]
      9. *-commutative99.9%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\color{blue}{{\left(\left|x\right|\right)}^{4} \cdot 0.2} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right)\right| \]
      10. fma-def99.9%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\mathsf{fma}\left({\left(\left|x\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)}\right)\right| \]
      11. rem-square-sqrt0.0%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      12. fabs-sqr0.0%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      13. rem-square-sqrt99.9%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{x}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      14. fma-def99.9%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \color{blue}{\mathsf{fma}\left(0.047619047619047616, {\left(\left|x\right|\right)}^{6}, 2\right)}\right)\right)\right| \]
    6. Simplified99.9%

      \[\leadsto \left|\color{blue}{x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \mathsf{fma}\left(0.047619047619047616, {x}^{6}, 2\right)\right)\right)}\right| \]
    7. Taylor expanded in x around inf 99.6%

      \[\leadsto \left|\color{blue}{0.047619047619047616 \cdot \left({x}^{7} \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    8. Step-by-step derivation
      1. associate-*r*99.6%

        \[\leadsto \left|\color{blue}{\left(0.047619047619047616 \cdot {x}^{7}\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
      2. *-commutative99.6%

        \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)}\right| \]
    9. Simplified99.6%

      \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)}\right| \]
    10. Step-by-step derivation
      1. expm1-log1p-u0.0%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)\right)\right)}\right| \]
      2. expm1-udef0.0%

        \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)\right)} - 1}\right| \]
      3. pow1/20.0%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\left(\frac{1}{\pi}\right)}^{0.5}} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)\right)} - 1\right| \]
      4. inv-pow0.0%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\color{blue}{\left({\pi}^{-1}\right)}}^{0.5} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)\right)} - 1\right| \]
      5. pow-pow0.0%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\pi}^{\left(-1 \cdot 0.5\right)}} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)\right)} - 1\right| \]
      6. metadata-eval0.0%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{\color{blue}{-0.5}} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)\right)} - 1\right| \]
    11. Applied egg-rr0.0%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)\right)} - 1}\right| \]
    12. Step-by-step derivation
      1. expm1-def0.0%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)\right)\right)}\right| \]
      2. expm1-log1p99.6%

        \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(0.047619047619047616 \cdot {x}^{7}\right)}\right| \]
      3. *-commutative99.6%

        \[\leadsto \left|\color{blue}{\left(0.047619047619047616 \cdot {x}^{7}\right) \cdot {\pi}^{-0.5}}\right| \]
      4. associate-*l*99.6%

        \[\leadsto \left|\color{blue}{0.047619047619047616 \cdot \left({x}^{7} \cdot {\pi}^{-0.5}\right)}\right| \]
    13. Simplified99.6%

      \[\leadsto \left|\color{blue}{0.047619047619047616 \cdot \left({x}^{7} \cdot {\pi}^{-0.5}\right)}\right| \]

    if -1.8500000000000001 < x

    1. Initial program 99.8%

      \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
    2. Step-by-step derivation
      1. associate-+l+99.8%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
      2. +-commutative99.8%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    3. Simplified99.2%

      \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
    4. Taylor expanded in x around 0 99.6%

      \[\leadsto \left|\color{blue}{\left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \left|x\right|\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
    5. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto \left|\color{blue}{\left(\left|x\right| \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)} \cdot \sqrt{\frac{1}{\pi}}\right| \]
      2. associate-*l*99.6%

        \[\leadsto \left|\color{blue}{\left|x\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
      3. rem-square-sqrt56.0%

        \[\leadsto \left|\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      4. fabs-sqr56.0%

        \[\leadsto \left|\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      5. rem-square-sqrt99.6%

        \[\leadsto \left|\color{blue}{x} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      6. *-commutative99.6%

        \[\leadsto \left|x \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)}\right| \]
      7. +-commutative99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right) + 2\right)}\right)\right| \]
      8. associate-+l+99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)}\right)\right| \]
      9. *-commutative99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\color{blue}{{\left(\left|x\right|\right)}^{4} \cdot 0.2} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right)\right| \]
      10. fma-def99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\mathsf{fma}\left({\left(\left|x\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)}\right)\right| \]
      11. rem-square-sqrt56.3%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      12. fabs-sqr56.3%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      13. rem-square-sqrt99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{x}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      14. fma-def99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \color{blue}{\mathsf{fma}\left(0.047619047619047616, {\left(\left|x\right|\right)}^{6}, 2\right)}\right)\right)\right| \]
    6. Simplified99.6%

      \[\leadsto \left|\color{blue}{x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \mathsf{fma}\left(0.047619047619047616, {x}^{6}, 2\right)\right)\right)}\right| \]
    7. Taylor expanded in x around 0 99.6%

      \[\leadsto \left|\color{blue}{2 \cdot \left(x \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    8. Step-by-step derivation
      1. associate-*r*99.6%

        \[\leadsto \left|\color{blue}{\left(2 \cdot x\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
      2. *-commutative99.6%

        \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
    9. Simplified99.6%

      \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
    10. Step-by-step derivation
      1. expm1-log1p-u99.6%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)\right)}\right| \]
      2. expm1-udef8.4%

        \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)} - 1}\right| \]
      3. pow1/28.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\left(\frac{1}{\pi}\right)}^{0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      4. inv-pow8.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\color{blue}{\left({\pi}^{-1}\right)}}^{0.5} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      5. pow-pow8.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\pi}^{\left(-1 \cdot 0.5\right)}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      6. metadata-eval8.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{\color{blue}{-0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      7. *-commutative8.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \color{blue}{\left(x \cdot 2\right)}\right)} - 1\right| \]
    11. Applied egg-rr8.4%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)} - 1}\right| \]
    12. Step-by-step derivation
      1. expm1-def99.6%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)\right)}\right| \]
      2. expm1-log1p99.6%

        \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x \cdot 2\right)}\right| \]
      3. *-commutative99.6%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(2 \cdot x\right)}\right| \]
      4. rem-log-exp8.4%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \left(2 \cdot \color{blue}{\log \left(e^{x}\right)}\right)\right| \]
      5. log-pow8.3%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\log \left({\left(e^{x}\right)}^{2}\right)}\right| \]
      6. exp-prod8.4%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x \cdot 2}\right)}\right| \]
      7. exp-lft-sqr8.3%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x} \cdot e^{x}\right)}\right| \]
      8. log-prod8.4%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(\log \left(e^{x}\right) + \log \left(e^{x}\right)\right)}\right| \]
      9. rem-log-exp20.8%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \left(\color{blue}{x} + \log \left(e^{x}\right)\right)\right| \]
      10. rem-log-exp99.6%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \left(x + \color{blue}{x}\right)\right| \]
    13. Simplified99.6%

      \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x + x\right)}\right| \]
  3. Recombined 2 regimes into one program.
  4. Final simplification99.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1.85:\\ \;\;\;\;\left|0.047619047619047616 \cdot \left({\pi}^{-0.5} \cdot {x}^{7}\right)\right|\\ \mathbf{else}:\\ \;\;\;\;\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|\\ \end{array} \]

Alternative 6: 94.3% accurate, 4.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -1.72:\\ \;\;\;\;\left|0.6666666666666666 \cdot \sqrt{\frac{{x}^{6}}{\pi}}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -1.72)
   (fabs (* 0.6666666666666666 (sqrt (/ (pow x 6.0) PI))))
   (fabs (* (pow PI -0.5) (+ x x)))))
double code(double x) {
	double tmp;
	if (x <= -1.72) {
		tmp = fabs((0.6666666666666666 * sqrt((pow(x, 6.0) / ((double) M_PI)))));
	} else {
		tmp = fabs((pow(((double) M_PI), -0.5) * (x + x)));
	}
	return tmp;
}
public static double code(double x) {
	double tmp;
	if (x <= -1.72) {
		tmp = Math.abs((0.6666666666666666 * Math.sqrt((Math.pow(x, 6.0) / Math.PI))));
	} else {
		tmp = Math.abs((Math.pow(Math.PI, -0.5) * (x + x)));
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= -1.72:
		tmp = math.fabs((0.6666666666666666 * math.sqrt((math.pow(x, 6.0) / math.pi))))
	else:
		tmp = math.fabs((math.pow(math.pi, -0.5) * (x + x)))
	return tmp
function code(x)
	tmp = 0.0
	if (x <= -1.72)
		tmp = abs(Float64(0.6666666666666666 * sqrt(Float64((x ^ 6.0) / pi))));
	else
		tmp = abs(Float64((pi ^ -0.5) * Float64(x + x)));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= -1.72)
		tmp = abs((0.6666666666666666 * sqrt(((x ^ 6.0) / pi))));
	else
		tmp = abs(((pi ^ -0.5) * (x + x)));
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, -1.72], N[Abs[N[(0.6666666666666666 * N[Sqrt[N[(N[Power[x, 6.0], $MachinePrecision] / Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[Abs[N[(N[Power[Pi, -0.5], $MachinePrecision] * N[(x + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -1.72:\\
\;\;\;\;\left|0.6666666666666666 \cdot \sqrt{\frac{{x}^{6}}{\pi}}\right|\\

\mathbf{else}:\\
\;\;\;\;\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -1.71999999999999997

    1. Initial program 99.9%

      \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
    2. Step-by-step derivation
      1. associate-+l+99.9%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
      2. +-commutative99.9%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
    4. Taylor expanded in x around inf 75.5%

      \[\leadsto \left|\color{blue}{0.6666666666666666 \cdot \left(\left(\left|x\right| \cdot {x}^{2}\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    5. Step-by-step derivation
      1. unpow275.5%

        \[\leadsto \left|0.6666666666666666 \cdot \left(\left(\left|x\right| \cdot \color{blue}{\left(x \cdot x\right)}\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    6. Simplified75.5%

      \[\leadsto \left|\color{blue}{0.6666666666666666 \cdot \left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    7. Step-by-step derivation
      1. add-sqr-sqrt75.5%

        \[\leadsto \left|0.6666666666666666 \cdot \color{blue}{\left(\sqrt{\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}} \cdot \sqrt{\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}}\right)}\right| \]
      2. sqrt-unprod92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \color{blue}{\sqrt{\left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right) \cdot \left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}}\right| \]
      3. *-commutative92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right)} \cdot \left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
      4. *-commutative92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\left(\sqrt{\frac{1}{\pi}} \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right) \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right)}}\right| \]
      5. swap-sqr92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \sqrt{\frac{1}{\pi}}\right) \cdot \left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right)}}\right| \]
      6. add-sqr-sqrt92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\color{blue}{\frac{1}{\pi}} \cdot \left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right)}\right| \]
      7. pow292.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\frac{1}{\pi} \cdot \color{blue}{{\left(\left|x\right| \cdot \left(x \cdot x\right)\right)}^{2}}}\right| \]
      8. add-sqr-sqrt0.0%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\frac{1}{\pi} \cdot {\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \left(x \cdot x\right)\right)}^{2}}\right| \]
      9. fabs-sqr0.0%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\frac{1}{\pi} \cdot {\left(\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(x \cdot x\right)\right)}^{2}}\right| \]
      10. add-sqr-sqrt92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\frac{1}{\pi} \cdot {\left(\color{blue}{x} \cdot \left(x \cdot x\right)\right)}^{2}}\right| \]
      11. cube-mult92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\frac{1}{\pi} \cdot {\color{blue}{\left({x}^{3}\right)}}^{2}}\right| \]
      12. pow292.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\frac{1}{\pi} \cdot \color{blue}{\left({x}^{3} \cdot {x}^{3}\right)}}\right| \]
      13. pow-sqr92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\frac{1}{\pi} \cdot \color{blue}{{x}^{\left(2 \cdot 3\right)}}}\right| \]
      14. metadata-eval92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\frac{1}{\pi} \cdot {x}^{\color{blue}{6}}}\right| \]
    8. Applied egg-rr92.1%

      \[\leadsto \left|0.6666666666666666 \cdot \color{blue}{\sqrt{\frac{1}{\pi} \cdot {x}^{6}}}\right| \]
    9. Step-by-step derivation
      1. associate-*l/92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\color{blue}{\frac{1 \cdot {x}^{6}}{\pi}}}\right| \]
      2. *-lft-identity92.1%

        \[\leadsto \left|0.6666666666666666 \cdot \sqrt{\frac{\color{blue}{{x}^{6}}}{\pi}}\right| \]
    10. Simplified92.1%

      \[\leadsto \left|0.6666666666666666 \cdot \color{blue}{\sqrt{\frac{{x}^{6}}{\pi}}}\right| \]

    if -1.71999999999999997 < x

    1. Initial program 99.8%

      \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
    2. Step-by-step derivation
      1. associate-+l+99.8%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
      2. +-commutative99.8%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    3. Simplified99.2%

      \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
    4. Taylor expanded in x around 0 99.6%

      \[\leadsto \left|\color{blue}{\left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \left|x\right|\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
    5. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto \left|\color{blue}{\left(\left|x\right| \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)} \cdot \sqrt{\frac{1}{\pi}}\right| \]
      2. associate-*l*99.6%

        \[\leadsto \left|\color{blue}{\left|x\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
      3. rem-square-sqrt56.0%

        \[\leadsto \left|\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      4. fabs-sqr56.0%

        \[\leadsto \left|\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      5. rem-square-sqrt99.6%

        \[\leadsto \left|\color{blue}{x} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      6. *-commutative99.6%

        \[\leadsto \left|x \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)}\right| \]
      7. +-commutative99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right) + 2\right)}\right)\right| \]
      8. associate-+l+99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)}\right)\right| \]
      9. *-commutative99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\color{blue}{{\left(\left|x\right|\right)}^{4} \cdot 0.2} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right)\right| \]
      10. fma-def99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\mathsf{fma}\left({\left(\left|x\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)}\right)\right| \]
      11. rem-square-sqrt56.3%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      12. fabs-sqr56.3%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      13. rem-square-sqrt99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{x}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      14. fma-def99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \color{blue}{\mathsf{fma}\left(0.047619047619047616, {\left(\left|x\right|\right)}^{6}, 2\right)}\right)\right)\right| \]
    6. Simplified99.6%

      \[\leadsto \left|\color{blue}{x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \mathsf{fma}\left(0.047619047619047616, {x}^{6}, 2\right)\right)\right)}\right| \]
    7. Taylor expanded in x around 0 99.6%

      \[\leadsto \left|\color{blue}{2 \cdot \left(x \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    8. Step-by-step derivation
      1. associate-*r*99.6%

        \[\leadsto \left|\color{blue}{\left(2 \cdot x\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
      2. *-commutative99.6%

        \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
    9. Simplified99.6%

      \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
    10. Step-by-step derivation
      1. expm1-log1p-u99.6%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)\right)}\right| \]
      2. expm1-udef8.4%

        \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)} - 1}\right| \]
      3. pow1/28.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\left(\frac{1}{\pi}\right)}^{0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      4. inv-pow8.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\color{blue}{\left({\pi}^{-1}\right)}}^{0.5} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      5. pow-pow8.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\pi}^{\left(-1 \cdot 0.5\right)}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      6. metadata-eval8.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{\color{blue}{-0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      7. *-commutative8.4%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \color{blue}{\left(x \cdot 2\right)}\right)} - 1\right| \]
    11. Applied egg-rr8.4%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)} - 1}\right| \]
    12. Step-by-step derivation
      1. expm1-def99.6%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)\right)}\right| \]
      2. expm1-log1p99.6%

        \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x \cdot 2\right)}\right| \]
      3. *-commutative99.6%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(2 \cdot x\right)}\right| \]
      4. rem-log-exp8.4%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \left(2 \cdot \color{blue}{\log \left(e^{x}\right)}\right)\right| \]
      5. log-pow8.3%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\log \left({\left(e^{x}\right)}^{2}\right)}\right| \]
      6. exp-prod8.4%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x \cdot 2}\right)}\right| \]
      7. exp-lft-sqr8.3%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x} \cdot e^{x}\right)}\right| \]
      8. log-prod8.4%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(\log \left(e^{x}\right) + \log \left(e^{x}\right)\right)}\right| \]
      9. rem-log-exp20.8%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \left(\color{blue}{x} + \log \left(e^{x}\right)\right)\right| \]
      10. rem-log-exp99.6%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \left(x + \color{blue}{x}\right)\right| \]
    13. Simplified99.6%

      \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x + x\right)}\right| \]
  3. Recombined 2 regimes into one program.
  4. Final simplification97.1%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -1.72:\\ \;\;\;\;\left|0.6666666666666666 \cdot \sqrt{\frac{{x}^{6}}{\pi}}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|\\ \end{array} \]

Alternative 7: 95.0% accurate, 6.3× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq -9.2 \cdot 10^{+23}:\\ \;\;\;\;\left|\frac{1}{\sqrt{\pi} \cdot 0}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|\\ \end{array} \end{array} \]
(FPCore (x)
 :precision binary64
 (if (<= x -9.2e+23)
   (fabs (/ 1.0 (* (sqrt PI) 0.0)))
   (fabs (* (pow PI -0.5) (+ x x)))))
double code(double x) {
	double tmp;
	if (x <= -9.2e+23) {
		tmp = fabs((1.0 / (sqrt(((double) M_PI)) * 0.0)));
	} else {
		tmp = fabs((pow(((double) M_PI), -0.5) * (x + x)));
	}
	return tmp;
}
public static double code(double x) {
	double tmp;
	if (x <= -9.2e+23) {
		tmp = Math.abs((1.0 / (Math.sqrt(Math.PI) * 0.0)));
	} else {
		tmp = Math.abs((Math.pow(Math.PI, -0.5) * (x + x)));
	}
	return tmp;
}
def code(x):
	tmp = 0
	if x <= -9.2e+23:
		tmp = math.fabs((1.0 / (math.sqrt(math.pi) * 0.0)))
	else:
		tmp = math.fabs((math.pow(math.pi, -0.5) * (x + x)))
	return tmp
function code(x)
	tmp = 0.0
	if (x <= -9.2e+23)
		tmp = abs(Float64(1.0 / Float64(sqrt(pi) * 0.0)));
	else
		tmp = abs(Float64((pi ^ -0.5) * Float64(x + x)));
	end
	return tmp
end
function tmp_2 = code(x)
	tmp = 0.0;
	if (x <= -9.2e+23)
		tmp = abs((1.0 / (sqrt(pi) * 0.0)));
	else
		tmp = abs(((pi ^ -0.5) * (x + x)));
	end
	tmp_2 = tmp;
end
code[x_] := If[LessEqual[x, -9.2e+23], N[Abs[N[(1.0 / N[(N[Sqrt[Pi], $MachinePrecision] * 0.0), $MachinePrecision]), $MachinePrecision]], $MachinePrecision], N[Abs[N[(N[Power[Pi, -0.5], $MachinePrecision] * N[(x + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq -9.2 \cdot 10^{+23}:\\
\;\;\;\;\left|\frac{1}{\sqrt{\pi} \cdot 0}\right|\\

\mathbf{else}:\\
\;\;\;\;\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < -9.2000000000000002e23

    1. Initial program 99.9%

      \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
    2. Step-by-step derivation
      1. associate-+l+99.9%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
      2. +-commutative99.9%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    3. Simplified100.0%

      \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
    4. Taylor expanded in x around inf 76.3%

      \[\leadsto \left|\color{blue}{0.6666666666666666 \cdot \left(\left(\left|x\right| \cdot {x}^{2}\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    5. Step-by-step derivation
      1. associate-*r*76.3%

        \[\leadsto \left|\color{blue}{\left(0.6666666666666666 \cdot \left(\left|x\right| \cdot {x}^{2}\right)\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
      2. *-commutative76.3%

        \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(0.6666666666666666 \cdot \left(\left|x\right| \cdot {x}^{2}\right)\right)}\right| \]
      3. unpow276.3%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(0.6666666666666666 \cdot \left(\left|x\right| \cdot \color{blue}{\left(x \cdot x\right)}\right)\right)\right| \]
      4. *-commutative76.3%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(0.6666666666666666 \cdot \color{blue}{\left(\left(x \cdot x\right) \cdot \left|x\right|\right)}\right)\right| \]
      5. associate-*r*76.3%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\left(0.6666666666666666 \cdot \left(x \cdot x\right)\right) \cdot \left|x\right|\right)}\right| \]
      6. rem-square-sqrt0.0%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(\left(0.6666666666666666 \cdot \left(x \cdot x\right)\right) \cdot \left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)\right| \]
      7. fabs-sqr0.0%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(\left(0.6666666666666666 \cdot \left(x \cdot x\right)\right) \cdot \color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}\right)\right| \]
      8. rem-square-sqrt76.3%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(\left(0.6666666666666666 \cdot \left(x \cdot x\right)\right) \cdot \color{blue}{x}\right)\right| \]
      9. associate-*r*76.3%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(0.6666666666666666 \cdot \left(\left(x \cdot x\right) \cdot x\right)\right)}\right| \]
      10. unpow376.3%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(0.6666666666666666 \cdot \color{blue}{{x}^{3}}\right)\right| \]
    6. Simplified76.3%

      \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(0.6666666666666666 \cdot {x}^{3}\right)}\right| \]
    7. Step-by-step derivation
      1. *-commutative76.3%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left({x}^{3} \cdot 0.6666666666666666\right)}\right| \]
      2. cube-mult76.3%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(\color{blue}{\left(x \cdot \left(x \cdot x\right)\right)} \cdot 0.6666666666666666\right)\right| \]
      3. add-sqr-sqrt0.0%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(\left(\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(x \cdot x\right)\right) \cdot 0.6666666666666666\right)\right| \]
      4. fabs-sqr0.0%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(\left(\color{blue}{\left|\sqrt{x} \cdot \sqrt{x}\right|} \cdot \left(x \cdot x\right)\right) \cdot 0.6666666666666666\right)\right| \]
      5. add-sqr-sqrt76.3%

        \[\leadsto \left|\sqrt{\frac{1}{\pi}} \cdot \left(\left(\left|\color{blue}{x}\right| \cdot \left(x \cdot x\right)\right) \cdot 0.6666666666666666\right)\right| \]
      6. associate-*l*76.3%

        \[\leadsto \left|\color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(\left|x\right| \cdot \left(x \cdot x\right)\right)\right) \cdot 0.6666666666666666}\right| \]
      7. *-commutative76.3%

        \[\leadsto \left|\color{blue}{\left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)} \cdot 0.6666666666666666\right| \]
      8. *-commutative76.3%

        \[\leadsto \left|\color{blue}{0.6666666666666666 \cdot \left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
      9. expm1-log1p-u76.3%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(0.6666666666666666 \cdot \left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)}\right| \]
      10. expm1-udef76.3%

        \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(0.6666666666666666 \cdot \left(\left(\left|x\right| \cdot \left(x \cdot x\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right)} - 1}\right| \]
    8. Applied egg-rr0.0%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(0.6666666666666666 \cdot \frac{{x}^{3}}{\sqrt{\pi}}\right)} - 1}\right| \]
    9. Step-by-step derivation
      1. expm1-def0.0%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(0.6666666666666666 \cdot \frac{{x}^{3}}{\sqrt{\pi}}\right)\right)}\right| \]
      2. expm1-log1p76.3%

        \[\leadsto \left|\color{blue}{0.6666666666666666 \cdot \frac{{x}^{3}}{\sqrt{\pi}}}\right| \]
      3. associate-*r/76.3%

        \[\leadsto \left|\color{blue}{\frac{0.6666666666666666 \cdot {x}^{3}}{\sqrt{\pi}}}\right| \]
    10. Simplified76.3%

      \[\leadsto \left|\color{blue}{\frac{0.6666666666666666 \cdot {x}^{3}}{\sqrt{\pi}}}\right| \]
    11. Step-by-step derivation
      1. expm1-log1p-u0.0%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{0.6666666666666666 \cdot {x}^{3}}{\sqrt{\pi}}\right)\right)}\right| \]
      2. expm1-udef0.0%

        \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\frac{0.6666666666666666 \cdot {x}^{3}}{\sqrt{\pi}}\right)} - 1}\right| \]
      3. associate-/l*0.0%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{\frac{0.6666666666666666}{\frac{\sqrt{\pi}}{{x}^{3}}}}\right)} - 1\right| \]
    12. Applied egg-rr0.0%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\frac{0.6666666666666666}{\frac{\sqrt{\pi}}{{x}^{3}}}\right)} - 1}\right| \]
    13. Step-by-step derivation
      1. expm1-def0.0%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{0.6666666666666666}{\frac{\sqrt{\pi}}{{x}^{3}}}\right)\right)}\right| \]
      2. expm1-log1p76.3%

        \[\leadsto \left|\color{blue}{\frac{0.6666666666666666}{\frac{\sqrt{\pi}}{{x}^{3}}}}\right| \]
      3. associate-/r/76.3%

        \[\leadsto \left|\color{blue}{\frac{0.6666666666666666}{\sqrt{\pi}} \cdot {x}^{3}}\right| \]
      4. *-commutative76.3%

        \[\leadsto \left|\color{blue}{{x}^{3} \cdot \frac{0.6666666666666666}{\sqrt{\pi}}}\right| \]
    14. Simplified76.3%

      \[\leadsto \left|\color{blue}{{x}^{3} \cdot \frac{0.6666666666666666}{\sqrt{\pi}}}\right| \]
    15. Step-by-step derivation
      1. expm1-log1p-u0.0%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({x}^{3} \cdot \frac{0.6666666666666666}{\sqrt{\pi}}\right)\right)}\right| \]
      2. expm1-udef0.0%

        \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left({x}^{3} \cdot \frac{0.6666666666666666}{\sqrt{\pi}}\right)} - 1}\right| \]
      3. clear-num0.0%

        \[\leadsto \left|e^{\mathsf{log1p}\left({x}^{3} \cdot \color{blue}{\frac{1}{\frac{\sqrt{\pi}}{0.6666666666666666}}}\right)} - 1\right| \]
      4. un-div-inv0.0%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{\frac{{x}^{3}}{\frac{\sqrt{\pi}}{0.6666666666666666}}}\right)} - 1\right| \]
      5. div-inv0.0%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\frac{{x}^{3}}{\color{blue}{\sqrt{\pi} \cdot \frac{1}{0.6666666666666666}}}\right)} - 1\right| \]
      6. metadata-eval0.0%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\frac{{x}^{3}}{\sqrt{\pi} \cdot \color{blue}{1.5}}\right)} - 1\right| \]
    16. Applied egg-rr0.0%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\frac{{x}^{3}}{\sqrt{\pi} \cdot 1.5}\right)} - 1}\right| \]
    17. Simplified95.5%

      \[\leadsto \left|\color{blue}{\frac{{x}^{0}}{0 \cdot \sqrt{\pi}}}\right| \]

    if -9.2000000000000002e23 < x

    1. Initial program 99.8%

      \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
    2. Step-by-step derivation
      1. associate-+l+99.8%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
      2. +-commutative99.8%

        \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    3. Simplified99.2%

      \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
    4. Taylor expanded in x around 0 99.6%

      \[\leadsto \left|\color{blue}{\left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \left|x\right|\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
    5. Step-by-step derivation
      1. *-commutative99.6%

        \[\leadsto \left|\color{blue}{\left(\left|x\right| \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)} \cdot \sqrt{\frac{1}{\pi}}\right| \]
      2. associate-*l*99.6%

        \[\leadsto \left|\color{blue}{\left|x\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
      3. rem-square-sqrt55.7%

        \[\leadsto \left|\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      4. fabs-sqr55.7%

        \[\leadsto \left|\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      5. rem-square-sqrt99.6%

        \[\leadsto \left|\color{blue}{x} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
      6. *-commutative99.6%

        \[\leadsto \left|x \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)}\right| \]
      7. +-commutative99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right) + 2\right)}\right)\right| \]
      8. associate-+l+99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)}\right)\right| \]
      9. *-commutative99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\color{blue}{{\left(\left|x\right|\right)}^{4} \cdot 0.2} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right)\right| \]
      10. fma-def99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\mathsf{fma}\left({\left(\left|x\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)}\right)\right| \]
      11. rem-square-sqrt56.0%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      12. fabs-sqr56.0%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      13. rem-square-sqrt99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{x}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
      14. fma-def99.6%

        \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \color{blue}{\mathsf{fma}\left(0.047619047619047616, {\left(\left|x\right|\right)}^{6}, 2\right)}\right)\right)\right| \]
    6. Simplified99.6%

      \[\leadsto \left|\color{blue}{x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \mathsf{fma}\left(0.047619047619047616, {x}^{6}, 2\right)\right)\right)}\right| \]
    7. Taylor expanded in x around 0 99.0%

      \[\leadsto \left|\color{blue}{2 \cdot \left(x \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    8. Step-by-step derivation
      1. associate-*r*99.0%

        \[\leadsto \left|\color{blue}{\left(2 \cdot x\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
      2. *-commutative99.0%

        \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
    9. Simplified99.0%

      \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
    10. Step-by-step derivation
      1. expm1-log1p-u99.0%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)\right)}\right| \]
      2. expm1-udef8.3%

        \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)} - 1}\right| \]
      3. pow1/28.3%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\left(\frac{1}{\pi}\right)}^{0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      4. inv-pow8.3%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\color{blue}{\left({\pi}^{-1}\right)}}^{0.5} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      5. pow-pow8.3%

        \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\pi}^{\left(-1 \cdot 0.5\right)}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      6. metadata-eval8.3%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{\color{blue}{-0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
      7. *-commutative8.3%

        \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \color{blue}{\left(x \cdot 2\right)}\right)} - 1\right| \]
    11. Applied egg-rr8.3%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)} - 1}\right| \]
    12. Step-by-step derivation
      1. expm1-def99.0%

        \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)\right)}\right| \]
      2. expm1-log1p99.0%

        \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x \cdot 2\right)}\right| \]
      3. *-commutative99.0%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(2 \cdot x\right)}\right| \]
      4. rem-log-exp8.3%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \left(2 \cdot \color{blue}{\log \left(e^{x}\right)}\right)\right| \]
      5. log-pow8.3%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\log \left({\left(e^{x}\right)}^{2}\right)}\right| \]
      6. exp-prod8.4%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x \cdot 2}\right)}\right| \]
      7. exp-lft-sqr8.3%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x} \cdot e^{x}\right)}\right| \]
      8. log-prod8.3%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(\log \left(e^{x}\right) + \log \left(e^{x}\right)\right)}\right| \]
      9. rem-log-exp20.7%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \left(\color{blue}{x} + \log \left(e^{x}\right)\right)\right| \]
      10. rem-log-exp99.0%

        \[\leadsto \left|{\pi}^{-0.5} \cdot \left(x + \color{blue}{x}\right)\right| \]
    13. Simplified99.0%

      \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x + x\right)}\right| \]
  3. Recombined 2 regimes into one program.
  4. Final simplification97.9%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq -9.2 \cdot 10^{+23}:\\ \;\;\;\;\left|\frac{1}{\sqrt{\pi} \cdot 0}\right|\\ \mathbf{else}:\\ \;\;\;\;\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|\\ \end{array} \]

Alternative 8: 68.0% accurate, 6.4× speedup?

\[\begin{array}{l} \\ \left|{\pi}^{-0.5} \cdot \left(x + x\right)\right| \end{array} \]
(FPCore (x) :precision binary64 (fabs (* (pow PI -0.5) (+ x x))))
double code(double x) {
	return fabs((pow(((double) M_PI), -0.5) * (x + x)));
}
public static double code(double x) {
	return Math.abs((Math.pow(Math.PI, -0.5) * (x + x)));
}
def code(x):
	return math.fabs((math.pow(math.pi, -0.5) * (x + x)))
function code(x)
	return abs(Float64((pi ^ -0.5) * Float64(x + x)))
end
function tmp = code(x)
	tmp = abs(((pi ^ -0.5) * (x + x)));
end
code[x_] := N[Abs[N[(N[Power[Pi, -0.5], $MachinePrecision] * N[(x + x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|{\pi}^{-0.5} \cdot \left(x + x\right)\right|
\end{array}
Derivation
  1. Initial program 99.9%

    \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
  2. Step-by-step derivation
    1. associate-+l+99.9%

      \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    2. +-commutative99.9%

      \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
  4. Taylor expanded in x around 0 99.7%

    \[\leadsto \left|\color{blue}{\left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \left|x\right|\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
  5. Step-by-step derivation
    1. *-commutative99.7%

      \[\leadsto \left|\color{blue}{\left(\left|x\right| \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)} \cdot \sqrt{\frac{1}{\pi}}\right| \]
    2. associate-*l*99.7%

      \[\leadsto \left|\color{blue}{\left|x\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    3. rem-square-sqrt37.6%

      \[\leadsto \left|\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    4. fabs-sqr37.6%

      \[\leadsto \left|\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    5. rem-square-sqrt99.7%

      \[\leadsto \left|\color{blue}{x} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    6. *-commutative99.7%

      \[\leadsto \left|x \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)}\right| \]
    7. +-commutative99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right) + 2\right)}\right)\right| \]
    8. associate-+l+99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)}\right)\right| \]
    9. *-commutative99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\color{blue}{{\left(\left|x\right|\right)}^{4} \cdot 0.2} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right)\right| \]
    10. fma-def99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\mathsf{fma}\left({\left(\left|x\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)}\right)\right| \]
    11. rem-square-sqrt37.8%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    12. fabs-sqr37.8%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    13. rem-square-sqrt99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{x}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    14. fma-def99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \color{blue}{\mathsf{fma}\left(0.047619047619047616, {\left(\left|x\right|\right)}^{6}, 2\right)}\right)\right)\right| \]
  6. Simplified99.7%

    \[\leadsto \left|\color{blue}{x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \mathsf{fma}\left(0.047619047619047616, {x}^{6}, 2\right)\right)\right)}\right| \]
  7. Taylor expanded in x around 0 68.8%

    \[\leadsto \left|\color{blue}{2 \cdot \left(x \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
  8. Step-by-step derivation
    1. associate-*r*68.8%

      \[\leadsto \left|\color{blue}{\left(2 \cdot x\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
    2. *-commutative68.8%

      \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
  9. Simplified68.8%

    \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
  10. Step-by-step derivation
    1. expm1-log1p-u66.9%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)\right)}\right| \]
    2. expm1-udef5.6%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)} - 1}\right| \]
    3. pow1/25.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\left(\frac{1}{\pi}\right)}^{0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    4. inv-pow5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\color{blue}{\left({\pi}^{-1}\right)}}^{0.5} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    5. pow-pow5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\pi}^{\left(-1 \cdot 0.5\right)}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    6. metadata-eval5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{\color{blue}{-0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    7. *-commutative5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \color{blue}{\left(x \cdot 2\right)}\right)} - 1\right| \]
  11. Applied egg-rr5.6%

    \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)} - 1}\right| \]
  12. Step-by-step derivation
    1. expm1-def66.9%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)\right)}\right| \]
    2. expm1-log1p68.8%

      \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x \cdot 2\right)}\right| \]
    3. *-commutative68.8%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(2 \cdot x\right)}\right| \]
    4. rem-log-exp36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(2 \cdot \color{blue}{\log \left(e^{x}\right)}\right)\right| \]
    5. log-pow36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\log \left({\left(e^{x}\right)}^{2}\right)}\right| \]
    6. exp-prod36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x \cdot 2}\right)}\right| \]
    7. exp-lft-sqr36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x} \cdot e^{x}\right)}\right| \]
    8. log-prod36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(\log \left(e^{x}\right) + \log \left(e^{x}\right)\right)}\right| \]
    9. rem-log-exp45.0%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(\color{blue}{x} + \log \left(e^{x}\right)\right)\right| \]
    10. rem-log-exp68.8%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(x + \color{blue}{x}\right)\right| \]
  13. Simplified68.8%

    \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x + x\right)}\right| \]
  14. Final simplification68.8%

    \[\leadsto \left|{\pi}^{-0.5} \cdot \left(x + x\right)\right| \]

Alternative 9: 67.5% accurate, 6.4× speedup?

\[\begin{array}{l} \\ \left|\frac{2}{\frac{\sqrt{\pi}}{x}}\right| \end{array} \]
(FPCore (x) :precision binary64 (fabs (/ 2.0 (/ (sqrt PI) x))))
double code(double x) {
	return fabs((2.0 / (sqrt(((double) M_PI)) / x)));
}
public static double code(double x) {
	return Math.abs((2.0 / (Math.sqrt(Math.PI) / x)));
}
def code(x):
	return math.fabs((2.0 / (math.sqrt(math.pi) / x)))
function code(x)
	return abs(Float64(2.0 / Float64(sqrt(pi) / x)))
end
function tmp = code(x)
	tmp = abs((2.0 / (sqrt(pi) / x)));
end
code[x_] := N[Abs[N[(2.0 / N[(N[Sqrt[Pi], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|\frac{2}{\frac{\sqrt{\pi}}{x}}\right|
\end{array}
Derivation
  1. Initial program 99.9%

    \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
  2. Step-by-step derivation
    1. associate-+l+99.9%

      \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    2. +-commutative99.9%

      \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
  4. Taylor expanded in x around 0 99.7%

    \[\leadsto \left|\color{blue}{\left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \left|x\right|\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
  5. Step-by-step derivation
    1. *-commutative99.7%

      \[\leadsto \left|\color{blue}{\left(\left|x\right| \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)} \cdot \sqrt{\frac{1}{\pi}}\right| \]
    2. associate-*l*99.7%

      \[\leadsto \left|\color{blue}{\left|x\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    3. rem-square-sqrt37.6%

      \[\leadsto \left|\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    4. fabs-sqr37.6%

      \[\leadsto \left|\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    5. rem-square-sqrt99.7%

      \[\leadsto \left|\color{blue}{x} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    6. *-commutative99.7%

      \[\leadsto \left|x \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)}\right| \]
    7. +-commutative99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right) + 2\right)}\right)\right| \]
    8. associate-+l+99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)}\right)\right| \]
    9. *-commutative99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\color{blue}{{\left(\left|x\right|\right)}^{4} \cdot 0.2} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right)\right| \]
    10. fma-def99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\mathsf{fma}\left({\left(\left|x\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)}\right)\right| \]
    11. rem-square-sqrt37.8%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    12. fabs-sqr37.8%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    13. rem-square-sqrt99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{x}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    14. fma-def99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \color{blue}{\mathsf{fma}\left(0.047619047619047616, {\left(\left|x\right|\right)}^{6}, 2\right)}\right)\right)\right| \]
  6. Simplified99.7%

    \[\leadsto \left|\color{blue}{x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \mathsf{fma}\left(0.047619047619047616, {x}^{6}, 2\right)\right)\right)}\right| \]
  7. Taylor expanded in x around 0 68.8%

    \[\leadsto \left|\color{blue}{2 \cdot \left(x \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
  8. Step-by-step derivation
    1. associate-*r*68.8%

      \[\leadsto \left|\color{blue}{\left(2 \cdot x\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
    2. *-commutative68.8%

      \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
  9. Simplified68.8%

    \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
  10. Step-by-step derivation
    1. expm1-log1p-u66.9%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)\right)}\right| \]
    2. expm1-udef5.6%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)} - 1}\right| \]
    3. pow1/25.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\left(\frac{1}{\pi}\right)}^{0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    4. inv-pow5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\color{blue}{\left({\pi}^{-1}\right)}}^{0.5} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    5. pow-pow5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\pi}^{\left(-1 \cdot 0.5\right)}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    6. metadata-eval5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{\color{blue}{-0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    7. *-commutative5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \color{blue}{\left(x \cdot 2\right)}\right)} - 1\right| \]
  11. Applied egg-rr5.6%

    \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)} - 1}\right| \]
  12. Step-by-step derivation
    1. expm1-def66.9%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)\right)}\right| \]
    2. expm1-log1p68.8%

      \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x \cdot 2\right)}\right| \]
    3. *-commutative68.8%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(2 \cdot x\right)}\right| \]
    4. rem-log-exp36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(2 \cdot \color{blue}{\log \left(e^{x}\right)}\right)\right| \]
    5. log-pow36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\log \left({\left(e^{x}\right)}^{2}\right)}\right| \]
    6. exp-prod36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x \cdot 2}\right)}\right| \]
    7. exp-lft-sqr36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x} \cdot e^{x}\right)}\right| \]
    8. log-prod36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(\log \left(e^{x}\right) + \log \left(e^{x}\right)\right)}\right| \]
    9. rem-log-exp45.0%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(\color{blue}{x} + \log \left(e^{x}\right)\right)\right| \]
    10. rem-log-exp68.8%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(x + \color{blue}{x}\right)\right| \]
  13. Simplified68.8%

    \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x + x\right)}\right| \]
  14. Step-by-step derivation
    1. *-commutative68.8%

      \[\leadsto \left|\color{blue}{\left(x + x\right) \cdot {\pi}^{-0.5}}\right| \]
    2. count-268.8%

      \[\leadsto \left|\color{blue}{\left(2 \cdot x\right)} \cdot {\pi}^{-0.5}\right| \]
    3. associate-*r*68.8%

      \[\leadsto \left|\color{blue}{2 \cdot \left(x \cdot {\pi}^{-0.5}\right)}\right| \]
    4. metadata-eval68.8%

      \[\leadsto \left|2 \cdot \left(x \cdot {\pi}^{\color{blue}{\left(-0.5\right)}}\right)\right| \]
    5. pow-flip68.8%

      \[\leadsto \left|2 \cdot \left(x \cdot \color{blue}{\frac{1}{{\pi}^{0.5}}}\right)\right| \]
    6. pow1/268.8%

      \[\leadsto \left|2 \cdot \left(x \cdot \frac{1}{\color{blue}{\sqrt{\pi}}}\right)\right| \]
    7. div-inv68.4%

      \[\leadsto \left|2 \cdot \color{blue}{\frac{x}{\sqrt{\pi}}}\right| \]
    8. add-sqr-sqrt37.4%

      \[\leadsto \left|2 \cdot \frac{\color{blue}{\sqrt{x} \cdot \sqrt{x}}}{\sqrt{\pi}}\right| \]
    9. fabs-sqr37.4%

      \[\leadsto \left|2 \cdot \frac{\color{blue}{\left|\sqrt{x} \cdot \sqrt{x}\right|}}{\sqrt{\pi}}\right| \]
    10. add-sqr-sqrt68.4%

      \[\leadsto \left|2 \cdot \frac{\left|\color{blue}{x}\right|}{\sqrt{\pi}}\right| \]
    11. clear-num68.3%

      \[\leadsto \left|2 \cdot \color{blue}{\frac{1}{\frac{\sqrt{\pi}}{\left|x\right|}}}\right| \]
    12. un-div-inv68.3%

      \[\leadsto \left|\color{blue}{\frac{2}{\frac{\sqrt{\pi}}{\left|x\right|}}}\right| \]
    13. add-sqr-sqrt37.5%

      \[\leadsto \left|\frac{2}{\frac{\sqrt{\pi}}{\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|}}\right| \]
    14. fabs-sqr37.5%

      \[\leadsto \left|\frac{2}{\frac{\sqrt{\pi}}{\color{blue}{\sqrt{x} \cdot \sqrt{x}}}}\right| \]
    15. add-sqr-sqrt68.3%

      \[\leadsto \left|\frac{2}{\frac{\sqrt{\pi}}{\color{blue}{x}}}\right| \]
  15. Applied egg-rr68.3%

    \[\leadsto \left|\color{blue}{\frac{2}{\frac{\sqrt{\pi}}{x}}}\right| \]
  16. Final simplification68.3%

    \[\leadsto \left|\frac{2}{\frac{\sqrt{\pi}}{x}}\right| \]

Alternative 10: 14.4% accurate, 6.5× speedup?

\[\begin{array}{l} \\ \left|\frac{x}{\sqrt{\pi}}\right| \end{array} \]
(FPCore (x) :precision binary64 (fabs (/ x (sqrt PI))))
double code(double x) {
	return fabs((x / sqrt(((double) M_PI))));
}
public static double code(double x) {
	return Math.abs((x / Math.sqrt(Math.PI)));
}
def code(x):
	return math.fabs((x / math.sqrt(math.pi)))
function code(x)
	return abs(Float64(x / sqrt(pi)))
end
function tmp = code(x)
	tmp = abs((x / sqrt(pi)));
end
code[x_] := N[Abs[N[(x / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\left|\frac{x}{\sqrt{\pi}}\right|
\end{array}
Derivation
  1. Initial program 99.9%

    \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
  2. Step-by-step derivation
    1. associate-+l+99.9%

      \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    2. +-commutative99.9%

      \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
  4. Taylor expanded in x around 0 99.7%

    \[\leadsto \left|\color{blue}{\left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \left|x\right|\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
  5. Step-by-step derivation
    1. *-commutative99.7%

      \[\leadsto \left|\color{blue}{\left(\left|x\right| \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)} \cdot \sqrt{\frac{1}{\pi}}\right| \]
    2. associate-*l*99.7%

      \[\leadsto \left|\color{blue}{\left|x\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    3. rem-square-sqrt37.6%

      \[\leadsto \left|\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    4. fabs-sqr37.6%

      \[\leadsto \left|\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    5. rem-square-sqrt99.7%

      \[\leadsto \left|\color{blue}{x} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    6. *-commutative99.7%

      \[\leadsto \left|x \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)}\right| \]
    7. +-commutative99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right) + 2\right)}\right)\right| \]
    8. associate-+l+99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)}\right)\right| \]
    9. *-commutative99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\color{blue}{{\left(\left|x\right|\right)}^{4} \cdot 0.2} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right)\right| \]
    10. fma-def99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\mathsf{fma}\left({\left(\left|x\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)}\right)\right| \]
    11. rem-square-sqrt37.8%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    12. fabs-sqr37.8%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    13. rem-square-sqrt99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{x}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    14. fma-def99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \color{blue}{\mathsf{fma}\left(0.047619047619047616, {\left(\left|x\right|\right)}^{6}, 2\right)}\right)\right)\right| \]
  6. Simplified99.7%

    \[\leadsto \left|\color{blue}{x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \mathsf{fma}\left(0.047619047619047616, {x}^{6}, 2\right)\right)\right)}\right| \]
  7. Taylor expanded in x around 0 68.8%

    \[\leadsto \left|\color{blue}{2 \cdot \left(x \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
  8. Step-by-step derivation
    1. associate-*r*68.8%

      \[\leadsto \left|\color{blue}{\left(2 \cdot x\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
    2. *-commutative68.8%

      \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
  9. Simplified68.8%

    \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
  10. Step-by-step derivation
    1. expm1-log1p-u66.9%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)\right)}\right| \]
    2. expm1-udef5.6%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)} - 1}\right| \]
    3. pow1/25.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\left(\frac{1}{\pi}\right)}^{0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    4. inv-pow5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\color{blue}{\left({\pi}^{-1}\right)}}^{0.5} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    5. pow-pow5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\pi}^{\left(-1 \cdot 0.5\right)}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    6. metadata-eval5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{\color{blue}{-0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    7. *-commutative5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \color{blue}{\left(x \cdot 2\right)}\right)} - 1\right| \]
  11. Applied egg-rr5.6%

    \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)} - 1}\right| \]
  12. Step-by-step derivation
    1. expm1-def66.9%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)\right)}\right| \]
    2. expm1-log1p68.8%

      \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x \cdot 2\right)}\right| \]
    3. *-commutative68.8%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(2 \cdot x\right)}\right| \]
    4. rem-log-exp36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(2 \cdot \color{blue}{\log \left(e^{x}\right)}\right)\right| \]
    5. log-pow36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\log \left({\left(e^{x}\right)}^{2}\right)}\right| \]
    6. exp-prod36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x \cdot 2}\right)}\right| \]
    7. exp-lft-sqr36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x} \cdot e^{x}\right)}\right| \]
    8. log-prod36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(\log \left(e^{x}\right) + \log \left(e^{x}\right)\right)}\right| \]
    9. rem-log-exp45.0%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(\color{blue}{x} + \log \left(e^{x}\right)\right)\right| \]
    10. rem-log-exp68.8%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(x + \color{blue}{x}\right)\right| \]
  13. Simplified68.8%

    \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x + x\right)}\right| \]
  14. Step-by-step derivation
    1. distribute-rgt-in68.8%

      \[\leadsto \left|\color{blue}{x \cdot {\pi}^{-0.5} + x \cdot {\pi}^{-0.5}}\right| \]
    2. metadata-eval68.8%

      \[\leadsto \left|x \cdot {\pi}^{\color{blue}{\left(-0.5\right)}} + x \cdot {\pi}^{-0.5}\right| \]
    3. pow-flip68.8%

      \[\leadsto \left|x \cdot \color{blue}{\frac{1}{{\pi}^{0.5}}} + x \cdot {\pi}^{-0.5}\right| \]
    4. pow1/268.8%

      \[\leadsto \left|x \cdot \frac{1}{\color{blue}{\sqrt{\pi}}} + x \cdot {\pi}^{-0.5}\right| \]
    5. div-inv68.5%

      \[\leadsto \left|\color{blue}{\frac{x}{\sqrt{\pi}}} + x \cdot {\pi}^{-0.5}\right| \]
    6. metadata-eval68.5%

      \[\leadsto \left|\frac{x}{\sqrt{\pi}} + x \cdot {\pi}^{\color{blue}{\left(-0.5\right)}}\right| \]
    7. pow-flip68.5%

      \[\leadsto \left|\frac{x}{\sqrt{\pi}} + x \cdot \color{blue}{\frac{1}{{\pi}^{0.5}}}\right| \]
    8. pow1/268.5%

      \[\leadsto \left|\frac{x}{\sqrt{\pi}} + x \cdot \frac{1}{\color{blue}{\sqrt{\pi}}}\right| \]
    9. div-inv68.4%

      \[\leadsto \left|\frac{x}{\sqrt{\pi}} + \color{blue}{\frac{x}{\sqrt{\pi}}}\right| \]
  15. Applied egg-rr68.4%

    \[\leadsto \left|\color{blue}{\frac{x}{\sqrt{\pi}} + \frac{x}{\sqrt{\pi}}}\right| \]
  16. Simplified14.5%

    \[\leadsto \left|\color{blue}{\frac{x}{\sqrt{\pi}}}\right| \]
  17. Final simplification14.5%

    \[\leadsto \left|\frac{x}{\sqrt{\pi}}\right| \]

Alternative 11: 4.1% accurate, 1948.0× speedup?

\[\begin{array}{l} \\ 0 \end{array} \]
(FPCore (x) :precision binary64 0.0)
double code(double x) {
	return 0.0;
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = 0.0d0
end function
public static double code(double x) {
	return 0.0;
}
def code(x):
	return 0.0
function code(x)
	return 0.0
end
function tmp = code(x)
	tmp = 0.0;
end
code[x_] := 0.0
\begin{array}{l}

\\
0
\end{array}
Derivation
  1. Initial program 99.9%

    \[\left|\frac{1}{\sqrt{\pi}} \cdot \left(\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right| \]
  2. Step-by-step derivation
    1. associate-+l+99.9%

      \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
    2. +-commutative99.9%

      \[\leadsto \left|\frac{1}{\sqrt{\pi}} \cdot \color{blue}{\left(\left(\frac{1}{5} \cdot \left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) + \frac{1}{21} \cdot \left(\left(\left(\left(\left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right) + \left(2 \cdot \left|x\right| + \frac{2}{3} \cdot \left(\left(\left|x\right| \cdot \left|x\right|\right) \cdot \left|x\right|\right)\right)\right)}\right| \]
  3. Simplified99.5%

    \[\leadsto \color{blue}{\left|\frac{\left|x\right| \cdot \left(\mathsf{fma}\left(0.6666666666666666, x \cdot x, 2\right) + \mathsf{fma}\left(0.2, {\left(\left|x\right|\right)}^{4}, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)}{\sqrt{\pi}}\right|} \]
  4. Taylor expanded in x around 0 99.7%

    \[\leadsto \left|\color{blue}{\left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \left|x\right|\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
  5. Step-by-step derivation
    1. *-commutative99.7%

      \[\leadsto \left|\color{blue}{\left(\left|x\right| \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)} \cdot \sqrt{\frac{1}{\pi}}\right| \]
    2. associate-*l*99.7%

      \[\leadsto \left|\color{blue}{\left|x\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
    3. rem-square-sqrt37.6%

      \[\leadsto \left|\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right| \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    4. fabs-sqr37.6%

      \[\leadsto \left|\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    5. rem-square-sqrt99.7%

      \[\leadsto \left|\color{blue}{x} \cdot \left(\left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right) \cdot \sqrt{\frac{1}{\pi}}\right)\right| \]
    6. *-commutative99.7%

      \[\leadsto \left|x \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 + \left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right)\right)\right)}\right| \]
    7. +-commutative99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6}\right) + 2\right)}\right)\right| \]
    8. associate-+l+99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(0.2 \cdot {\left(\left|x\right|\right)}^{4} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)}\right)\right| \]
    9. *-commutative99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\color{blue}{{\left(\left|x\right|\right)}^{4} \cdot 0.2} + \left(0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right)\right| \]
    10. fma-def99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\mathsf{fma}\left({\left(\left|x\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)}\right)\right| \]
    11. rem-square-sqrt37.8%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    12. fabs-sqr37.8%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    13. rem-square-sqrt99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({\color{blue}{x}}^{4}, 0.2, 0.047619047619047616 \cdot {\left(\left|x\right|\right)}^{6} + 2\right)\right)\right| \]
    14. fma-def99.7%

      \[\leadsto \left|x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \color{blue}{\mathsf{fma}\left(0.047619047619047616, {\left(\left|x\right|\right)}^{6}, 2\right)}\right)\right)\right| \]
  6. Simplified99.7%

    \[\leadsto \left|\color{blue}{x \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \mathsf{fma}\left({x}^{4}, 0.2, \mathsf{fma}\left(0.047619047619047616, {x}^{6}, 2\right)\right)\right)}\right| \]
  7. Taylor expanded in x around 0 68.8%

    \[\leadsto \left|\color{blue}{2 \cdot \left(x \cdot \sqrt{\frac{1}{\pi}}\right)}\right| \]
  8. Step-by-step derivation
    1. associate-*r*68.8%

      \[\leadsto \left|\color{blue}{\left(2 \cdot x\right) \cdot \sqrt{\frac{1}{\pi}}}\right| \]
    2. *-commutative68.8%

      \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
  9. Simplified68.8%

    \[\leadsto \left|\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)}\right| \]
  10. Step-by-step derivation
    1. expm1-log1p-u66.9%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)\right)}\right| \]
    2. expm1-udef5.6%

      \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left(\sqrt{\frac{1}{\pi}} \cdot \left(2 \cdot x\right)\right)} - 1}\right| \]
    3. pow1/25.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\left(\frac{1}{\pi}\right)}^{0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    4. inv-pow5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\color{blue}{\left({\pi}^{-1}\right)}}^{0.5} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    5. pow-pow5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left(\color{blue}{{\pi}^{\left(-1 \cdot 0.5\right)}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    6. metadata-eval5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{\color{blue}{-0.5}} \cdot \left(2 \cdot x\right)\right)} - 1\right| \]
    7. *-commutative5.6%

      \[\leadsto \left|e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \color{blue}{\left(x \cdot 2\right)}\right)} - 1\right| \]
  11. Applied egg-rr5.6%

    \[\leadsto \left|\color{blue}{e^{\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)} - 1}\right| \]
  12. Step-by-step derivation
    1. expm1-def66.9%

      \[\leadsto \left|\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\pi}^{-0.5} \cdot \left(x \cdot 2\right)\right)\right)}\right| \]
    2. expm1-log1p68.8%

      \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x \cdot 2\right)}\right| \]
    3. *-commutative68.8%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(2 \cdot x\right)}\right| \]
    4. rem-log-exp36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(2 \cdot \color{blue}{\log \left(e^{x}\right)}\right)\right| \]
    5. log-pow36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\log \left({\left(e^{x}\right)}^{2}\right)}\right| \]
    6. exp-prod36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x \cdot 2}\right)}\right| \]
    7. exp-lft-sqr36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \log \color{blue}{\left(e^{x} \cdot e^{x}\right)}\right| \]
    8. log-prod36.6%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \color{blue}{\left(\log \left(e^{x}\right) + \log \left(e^{x}\right)\right)}\right| \]
    9. rem-log-exp45.0%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(\color{blue}{x} + \log \left(e^{x}\right)\right)\right| \]
    10. rem-log-exp68.8%

      \[\leadsto \left|{\pi}^{-0.5} \cdot \left(x + \color{blue}{x}\right)\right| \]
  13. Simplified68.8%

    \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot \left(x + x\right)}\right| \]
  14. Step-by-step derivation
    1. distribute-lft-in68.8%

      \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot x + {\pi}^{-0.5} \cdot x}\right| \]
  15. Applied egg-rr68.8%

    \[\leadsto \left|\color{blue}{{\pi}^{-0.5} \cdot x + {\pi}^{-0.5} \cdot x}\right| \]
  16. Simplified4.2%

    \[\leadsto \left|\color{blue}{0}\right| \]
  17. Final simplification4.2%

    \[\leadsto 0 \]

Reproduce

?
herbie shell --seed 2023175 
(FPCore (x)
  :name "Jmat.Real.erfi, branch x less than or equal to 0.5"
  :precision binary64
  :pre (<= x 0.5)
  (fabs (* (/ 1.0 (sqrt PI)) (+ (+ (+ (* 2.0 (fabs x)) (* (/ 2.0 3.0) (* (* (fabs x) (fabs x)) (fabs x)))) (* (/ 1.0 5.0) (* (* (* (* (fabs x) (fabs x)) (fabs x)) (fabs x)) (fabs x)))) (* (/ 1.0 21.0) (* (* (* (* (* (* (fabs x) (fabs x)) (fabs x)) (fabs x)) (fabs x)) (fabs x)) (fabs x)))))))