Jmat.Real.erfi, branch x greater than or equal to 5

Percentage Accurate: 100.0% → 100.0%

Time: 18.5s

Alternatives: 9

Speedup: 3.5×

• 99.5% of points produce a very large (infinite) output. You may want to add a precondition.

Specification

\[x \geq 0.5\]

Math

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{1}{\left|x\right|}\\ t_1 := \left(t_0 \cdot t_0\right) \cdot t_0\\ t_2 := \left(t_1 \cdot t_0\right) \cdot t_0\\ \left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(t_0 + \frac{1}{2} \cdot t_1\right) + \frac{3}{4} \cdot t_2\right) + \frac{15}{8} \cdot \left(\left(t_2 \cdot t_0\right) \cdot t_0\right)\right) \end{array} \end{array} \]

FPCore

(FPCore (x)
 :precision binary64
 (let* ((t_0 (/ 1.0 (fabs x)))
        (t_1 (* (* t_0 t_0) t_0))
        (t_2 (* (* t_1 t_0) t_0)))
   (*
    (* (/ 1.0 (sqrt PI)) (exp (* (fabs x) (fabs x))))
    (+
     (+ (+ t_0 (* (/ 1.0 2.0) t_1)) (* (/ 3.0 4.0) t_2))
     (* (/ 15.0 8.0) (* (* t_2 t_0) t_0))))))

C

double code(double x) {
	double t_0 = 1.0 / fabs(x);
	double t_1 = (t_0 * t_0) * t_0;
	double t_2 = (t_1 * t_0) * t_0;
	return ((1.0 / sqrt(((double) M_PI))) * exp((fabs(x) * fabs(x)))) * (((t_0 + ((1.0 / 2.0) * t_1)) + ((3.0 / 4.0) * t_2)) + ((15.0 / 8.0) * ((t_2 * t_0) * t_0)));
}

Java

public static double code(double x) {
	double t_0 = 1.0 / Math.abs(x);
	double t_1 = (t_0 * t_0) * t_0;
	double t_2 = (t_1 * t_0) * t_0;
	return ((1.0 / Math.sqrt(Math.PI)) * Math.exp((Math.abs(x) * Math.abs(x)))) * (((t_0 + ((1.0 / 2.0) * t_1)) + ((3.0 / 4.0) * t_2)) + ((15.0 / 8.0) * ((t_2 * t_0) * t_0)));
}

Python

def code(x):
	t_0 = 1.0 / math.fabs(x)
	t_1 = (t_0 * t_0) * t_0
	t_2 = (t_1 * t_0) * t_0
	return ((1.0 / math.sqrt(math.pi)) * math.exp((math.fabs(x) * math.fabs(x)))) * (((t_0 + ((1.0 / 2.0) * t_1)) + ((3.0 / 4.0) * t_2)) + ((15.0 / 8.0) * ((t_2 * t_0) * t_0)))

Julia

function code(x)
	t_0 = Float64(1.0 / abs(x))
	t_1 = Float64(Float64(t_0 * t_0) * t_0)
	t_2 = Float64(Float64(t_1 * t_0) * t_0)
	return Float64(Float64(Float64(1.0 / sqrt(pi)) * exp(Float64(abs(x) * abs(x)))) * Float64(Float64(Float64(t_0 + Float64(Float64(1.0 / 2.0) * t_1)) + Float64(Float64(3.0 / 4.0) * t_2)) + Float64(Float64(15.0 / 8.0) * Float64(Float64(t_2 * t_0) * t_0))))
end

MATLAB

function tmp = code(x)
	t_0 = 1.0 / abs(x);
	t_1 = (t_0 * t_0) * t_0;
	t_2 = (t_1 * t_0) * t_0;
	tmp = ((1.0 / sqrt(pi)) * exp((abs(x) * abs(x)))) * (((t_0 + ((1.0 / 2.0) * t_1)) + ((3.0 / 4.0) * t_2)) + ((15.0 / 8.0) * ((t_2 * t_0) * t_0)));
end

Wolfram

code[x_] := Block[{t$95$0 = N[(1.0 / N[Abs[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(t$95$0 * t$95$0), $MachinePrecision] * t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(N[(t$95$1 * t$95$0), $MachinePrecision] * t$95$0), $MachinePrecision]}, N[(N[(N[(1.0 / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision] * N[Exp[N[(N[Abs[x], $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[(N[(N[(t$95$0 + N[(N[(1.0 / 2.0), $MachinePrecision] * t$95$1), $MachinePrecision]), $MachinePrecision] + N[(N[(3.0 / 4.0), $MachinePrecision] * t$95$2), $MachinePrecision]), $MachinePrecision] + N[(N[(15.0 / 8.0), $MachinePrecision] * N[(N[(t$95$2 * t$95$0), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]

Initial Program: 100.0% accurate, 1.0× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{1}{\left|x\right|}\\ t_1 := \left(t_0 \cdot t_0\right) \cdot t_0\\ t_2 := \left(t_1 \cdot t_0\right) \cdot t_0\\ \left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(t_0 + \frac{1}{2} \cdot t_1\right) + \frac{3}{4} \cdot t_2\right) + \frac{15}{8} \cdot \left(\left(t_2 \cdot t_0\right) \cdot t_0\right)\right) \end{array} \end{array} \]

FPCore

(FPCore (x)
 :precision binary64
 (let* ((t_0 (/ 1.0 (fabs x)))
        (t_1 (* (* t_0 t_0) t_0))
        (t_2 (* (* t_1 t_0) t_0)))
   (*
    (* (/ 1.0 (sqrt PI)) (exp (* (fabs x) (fabs x))))
    (+
     (+ (+ t_0 (* (/ 1.0 2.0) t_1)) (* (/ 3.0 4.0) t_2))
     (* (/ 15.0 8.0) (* (* t_2 t_0) t_0))))))

C

double code(double x) {
	double t_0 = 1.0 / fabs(x);
	double t_1 = (t_0 * t_0) * t_0;
	double t_2 = (t_1 * t_0) * t_0;
	return ((1.0 / sqrt(((double) M_PI))) * exp((fabs(x) * fabs(x)))) * (((t_0 + ((1.0 / 2.0) * t_1)) + ((3.0 / 4.0) * t_2)) + ((15.0 / 8.0) * ((t_2 * t_0) * t_0)));
}

Java

public static double code(double x) {
	double t_0 = 1.0 / Math.abs(x);
	double t_1 = (t_0 * t_0) * t_0;
	double t_2 = (t_1 * t_0) * t_0;
	return ((1.0 / Math.sqrt(Math.PI)) * Math.exp((Math.abs(x) * Math.abs(x)))) * (((t_0 + ((1.0 / 2.0) * t_1)) + ((3.0 / 4.0) * t_2)) + ((15.0 / 8.0) * ((t_2 * t_0) * t_0)));
}

Python

def code(x):
	t_0 = 1.0 / math.fabs(x)
	t_1 = (t_0 * t_0) * t_0
	t_2 = (t_1 * t_0) * t_0
	return ((1.0 / math.sqrt(math.pi)) * math.exp((math.fabs(x) * math.fabs(x)))) * (((t_0 + ((1.0 / 2.0) * t_1)) + ((3.0 / 4.0) * t_2)) + ((15.0 / 8.0) * ((t_2 * t_0) * t_0)))

Julia

function code(x)
	t_0 = Float64(1.0 / abs(x))
	t_1 = Float64(Float64(t_0 * t_0) * t_0)
	t_2 = Float64(Float64(t_1 * t_0) * t_0)
	return Float64(Float64(Float64(1.0 / sqrt(pi)) * exp(Float64(abs(x) * abs(x)))) * Float64(Float64(Float64(t_0 + Float64(Float64(1.0 / 2.0) * t_1)) + Float64(Float64(3.0 / 4.0) * t_2)) + Float64(Float64(15.0 / 8.0) * Float64(Float64(t_2 * t_0) * t_0))))
end

MATLAB

function tmp = code(x)
	t_0 = 1.0 / abs(x);
	t_1 = (t_0 * t_0) * t_0;
	t_2 = (t_1 * t_0) * t_0;
	tmp = ((1.0 / sqrt(pi)) * exp((abs(x) * abs(x)))) * (((t_0 + ((1.0 / 2.0) * t_1)) + ((3.0 / 4.0) * t_2)) + ((15.0 / 8.0) * ((t_2 * t_0) * t_0)));
end

Wolfram

code[x_] := Block[{t$95$0 = N[(1.0 / N[Abs[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[(N[(t$95$0 * t$95$0), $MachinePrecision] * t$95$0), $MachinePrecision]}, Block[{t$95$2 = N[(N[(t$95$1 * t$95$0), $MachinePrecision] * t$95$0), $MachinePrecision]}, N[(N[(N[(1.0 / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision] * N[Exp[N[(N[Abs[x], $MachinePrecision] * N[Abs[x], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] * N[(N[(N[(t$95$0 + N[(N[(1.0 / 2.0), $MachinePrecision] * t$95$1), $MachinePrecision]), $MachinePrecision] + N[(N[(3.0 / 4.0), $MachinePrecision] * t$95$2), $MachinePrecision]), $MachinePrecision] + N[(N[(15.0 / 8.0), $MachinePrecision] * N[(N[(t$95$2 * t$95$0), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]

Alternative 1: 100.0% accurate, 1.6× speedup

Math

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{1}{\left|x\right|}\\ \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {t_0}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{x}^{-2}}{x}, t_0\right)\right)\right) \end{array} \end{array} \]

FPCore

(FPCore (x)
 :precision binary64
 (let* ((t_0 (/ 1.0 (fabs x))))
   (*
    (/ (pow (exp x) x) (sqrt PI))
    (fma
     1.875
     (* (pow t_0 3.0) (pow (/ 1.0 x) 4.0))
     (fma
      0.75
      (+ (+ 1.0 (pow x -5.0)) -1.0)
      (fma 0.5 (/ (pow x -2.0) x) t_0))))))

C

double code(double x) {
	double t_0 = 1.0 / fabs(x);
	return (pow(exp(x), x) / sqrt(((double) M_PI))) * fma(1.875, (pow(t_0, 3.0) * pow((1.0 / x), 4.0)), fma(0.75, ((1.0 + pow(x, -5.0)) + -1.0), fma(0.5, (pow(x, -2.0) / x), t_0)));
}

Julia

function code(x)
	t_0 = Float64(1.0 / abs(x))
	return Float64(Float64((exp(x) ^ x) / sqrt(pi)) * fma(1.875, Float64((t_0 ^ 3.0) * (Float64(1.0 / x) ^ 4.0)), fma(0.75, Float64(Float64(1.0 + (x ^ -5.0)) + -1.0), fma(0.5, Float64((x ^ -2.0) / x), t_0))))
end

Wolfram

code[x_] := Block[{t$95$0 = N[(1.0 / N[Abs[x], $MachinePrecision]), $MachinePrecision]}, N[(N[(N[Power[N[Exp[x], $MachinePrecision], x], $MachinePrecision] / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision] * N[(1.875 * N[(N[Power[t$95$0, 3.0], $MachinePrecision] * N[Power[N[(1.0 / x), $MachinePrecision], 4.0], $MachinePrecision]), $MachinePrecision] + N[(0.75 * N[(N[(1.0 + N[Power[x, -5.0], $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision] + N[(0.5 * N[(N[Power[x, -2.0], $MachinePrecision] / x), $MachinePrecision] + t$95$0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]

Derivation

1. Initial program 100.0%

   \[\left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(\frac{1}{\left|x\right|} + \frac{1}{2} \cdot \left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{3}{4} \cdot \left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{15}{8} \cdot \left(\left(\left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) \]

3. Simplified 100.0%

   \[\leadsto \color{blue}{\frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, \frac{\frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}}{\left|x\right|}, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right)} \]
4. Step-by-step derivation

   1. expm1-log1p-u 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}}{\left|x\right|}\right)\right)}, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   2. expm1-udef 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, \color{blue}{e^{\mathsf{log1p}\left(\frac{\frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}}{\left|x\right|}\right)} - 1}, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   3. div-inv 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{\color{blue}{{\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{1}{\left|x\right|}}}{\left|x\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   4. pow-plus 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{\color{blue}{{\left(\frac{1}{\left|x\right|}\right)}^{\left(3 + 1\right)}}}{\left|x\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   5. metadata-eval 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{\left(\frac{1}{\left|x\right|}\right)}^{\color{blue}{4}}}{\left|x\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   6. inv-pow 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{\color{blue}{\left({\left(\left|x\right|\right)}^{-1}\right)}}^{4}}{\left|x\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   7. pow-pow 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{\color{blue}{{\left(\left|x\right|\right)}^{\left(-1 \cdot 4\right)}}}{\left|x\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   8. add-sqr-sqrt 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{\left(-1 \cdot 4\right)}}{\left|x\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   9. fabs-sqr 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{\left(-1 \cdot 4\right)}}{\left|x\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   10. add-sqr-sqrt 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{\color{blue}{x}}^{\left(-1 \cdot 4\right)}}{\left|x\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   11. metadata-eval 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{\color{blue}{-4}}}{\left|x\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   12. add-sqr-sqrt 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   13. fabs-sqr 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{\color{blue}{\sqrt{x} \cdot \sqrt{x}}}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   14. add-sqr-sqrt 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{\color{blue}{x}}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

5. Applied egg-rr 100.0%

   \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{{\left(\frac{1}{\left|x\right|}\right)}^{3}}{\left|x\right|}, \mathsf{fma}\left(0.75, \color{blue}{e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{x}\right)} - 1}, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]
6. Step-by-step derivation

   1. div-inv 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \color{blue}{\left({\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \frac{1}{\left|x\right|}\right)}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{x}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   2. pow-plus 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \color{blue}{{\left(\frac{1}{\left|x\right|}\right)}^{\left(3 + 1\right)}}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{x}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   3. metadata-eval 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{\left|x\right|}\right)}^{\color{blue}{4}}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{x}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   4. add-sqr-sqrt 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|}\right)}^{4}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{x}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   5. fabs-sqr 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{\color{blue}{\sqrt{x} \cdot \sqrt{x}}}\right)}^{4}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{x}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   6. add-sqr-sqrt 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{\color{blue}{x}}\right)}^{4}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{x}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

7. Applied egg-rr 100.0%

   \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot \color{blue}{{\left(\frac{1}{x}\right)}^{4}}, \mathsf{fma}\left(0.75, e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{x}\right)} - 1, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]
8. Step-by-step derivation

   1. sub-neg 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \color{blue}{e^{\mathsf{log1p}\left(\frac{{x}^{-4}}{x}\right)} + \left(-1\right)}, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   2. log1p-udef 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, e^{\color{blue}{\log \left(1 + \frac{{x}^{-4}}{x}\right)}} + \left(-1\right), \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   3. rem-exp-log 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \color{blue}{\left(1 + \frac{{x}^{-4}}{x}\right)} + \left(-1\right), \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   4. pow1 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + \frac{{x}^{-4}}{\color{blue}{{x}^{1}}}\right) + \left(-1\right), \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   5. pow-div 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + \color{blue}{{x}^{\left(-4 - 1\right)}}\right) + \left(-1\right), \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   6. metadata-eval 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{\color{blue}{-5}}\right) + \left(-1\right), \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

   7. metadata-eval 100.0%

      \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + \color{blue}{-1}, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]

9. Applied egg-rr 100.0%

   \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \color{blue}{\left(1 + {x}^{-5}\right) + -1}, \mathsf{fma}\left(0.5, {\left(\frac{1}{\left|x\right|}\right)}^{3}, \frac{1}{\left|x\right|}\right)\right)\right) \]
10. Step-by-step derivation

    1. unpow3 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \color{blue}{\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    2. un-div-inv 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \color{blue}{\frac{\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}}{\left|x\right|}}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    3. inv-pow 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{\color{blue}{{\left(\left|x\right|\right)}^{-1}} \cdot \frac{1}{\left|x\right|}}{\left|x\right|}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    4. inv-pow 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{\left(\left|x\right|\right)}^{-1} \cdot \color{blue}{{\left(\left|x\right|\right)}^{-1}}}{\left|x\right|}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    5. pow-prod-up 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{\color{blue}{{\left(\left|x\right|\right)}^{\left(-1 + -1\right)}}}{\left|x\right|}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    6. add-sqr-sqrt 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{\left(-1 + -1\right)}}{\left|x\right|}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    7. fabs-sqr 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{\left(-1 + -1\right)}}{\left|x\right|}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    8. add-sqr-sqrt 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{\color{blue}{x}}^{\left(-1 + -1\right)}}{\left|x\right|}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    9. metadata-eval 100.0%

       \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{x}^{\color{blue}{-2}}}{\left|x\right|}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    10. add-sqr-sqrt 100.0%

        \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{x}^{-2}}{\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    11. fabs-sqr 100.0%

        \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{x}^{-2}}{\color{blue}{\sqrt{x} \cdot \sqrt{x}}}, \frac{1}{\left|x\right|}\right)\right)\right) \]

    12. add-sqr-sqrt 100.0%

        \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{x}^{-2}}{\color{blue}{x}}, \frac{1}{\left|x\right|}\right)\right)\right) \]

11. Applied egg-rr 100.0%

    \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \color{blue}{\frac{{x}^{-2}}{x}}, \frac{1}{\left|x\right|}\right)\right)\right) \]

12. Final simplification 100.0%

    \[\leadsto \frac{{\left(e^{x}\right)}^{x}}{\sqrt{\pi}} \cdot \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{3} \cdot {\left(\frac{1}{x}\right)}^{4}, \mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(0.5, \frac{{x}^{-2}}{x}, \frac{1}{\left|x\right|}\right)\right)\right) \]

Alternative 2: 100.0% accurate, 2.4× speedup

Math

\[\begin{array}{l} \\ e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \end{array} \]

FPCore

(FPCore (x)
 :precision binary64
 (*
  (exp (* x x))
  (/
   (fma
    0.75
    (+ (+ 1.0 (pow x -5.0)) -1.0)
    (fma
     1.875
     (pow (/ 1.0 (fabs x)) 7.0)
     (/ (+ 1.0 (/ 0.5 (* x x))) (fabs x))))
   (sqrt PI))))

C

double code(double x) {
	return exp((x * x)) * (fma(0.75, ((1.0 + pow(x, -5.0)) + -1.0), fma(1.875, pow((1.0 / fabs(x)), 7.0), ((1.0 + (0.5 / (x * x))) / fabs(x)))) / sqrt(((double) M_PI)));
}

Julia

function code(x)
	return Float64(exp(Float64(x * x)) * Float64(fma(0.75, Float64(Float64(1.0 + (x ^ -5.0)) + -1.0), fma(1.875, (Float64(1.0 / abs(x)) ^ 7.0), Float64(Float64(1.0 + Float64(0.5 / Float64(x * x))) / abs(x)))) / sqrt(pi)))
end

Wolfram

code[x_] := N[(N[Exp[N[(x * x), $MachinePrecision]], $MachinePrecision] * N[(N[(0.75 * N[(N[(1.0 + N[Power[x, -5.0], $MachinePrecision]), $MachinePrecision] + -1.0), $MachinePrecision] + N[(1.875 * N[Power[N[(1.0 / N[Abs[x], $MachinePrecision]), $MachinePrecision], 7.0], $MachinePrecision] + N[(N[(1.0 + N[(0.5 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Abs[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[Sqrt[Pi], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 100.0%

   \[\left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(\frac{1}{\left|x\right|} + \frac{1}{2} \cdot \left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{3}{4} \cdot \left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{15}{8} \cdot \left(\left(\left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) \]

3. Simplified 100.0%

   \[\leadsto \color{blue}{e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}} \]
4. Step-by-step derivation

   1. add-sqr-sqrt 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\color{blue}{\left(\sqrt{\frac{1}{\left|x\right|}} \cdot \sqrt{\frac{1}{\left|x\right|}}\right)}}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   2. unpow-prod-down 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \color{blue}{{\left(\sqrt{\frac{1}{\left|x\right|}}\right)}^{5} \cdot {\left(\sqrt{\frac{1}{\left|x\right|}}\right)}^{5}}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   3. inv-pow 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left(\sqrt{\color{blue}{{\left(\left|x\right|\right)}^{-1}}}\right)}^{5} \cdot {\left(\sqrt{\frac{1}{\left|x\right|}}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   4. sqrt-pow1 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\color{blue}{\left({\left(\left|x\right|\right)}^{\left(\frac{-1}{2}\right)}\right)}}^{5} \cdot {\left(\sqrt{\frac{1}{\left|x\right|}}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   5. add-sqr-sqrt 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{\left(\frac{-1}{2}\right)}\right)}^{5} \cdot {\left(\sqrt{\frac{1}{\left|x\right|}}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   6. fabs-sqr 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{\left(\frac{-1}{2}\right)}\right)}^{5} \cdot {\left(\sqrt{\frac{1}{\left|x\right|}}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   7. add-sqr-sqrt 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({\color{blue}{x}}^{\left(\frac{-1}{2}\right)}\right)}^{5} \cdot {\left(\sqrt{\frac{1}{\left|x\right|}}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   8. metadata-eval 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({x}^{\color{blue}{-0.5}}\right)}^{5} \cdot {\left(\sqrt{\frac{1}{\left|x\right|}}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   9. inv-pow 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({x}^{-0.5}\right)}^{5} \cdot {\left(\sqrt{\color{blue}{{\left(\left|x\right|\right)}^{-1}}}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   10. sqrt-pow1 100.0%

       \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({x}^{-0.5}\right)}^{5} \cdot {\color{blue}{\left({\left(\left|x\right|\right)}^{\left(\frac{-1}{2}\right)}\right)}}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   11. add-sqr-sqrt 100.0%

       \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({x}^{-0.5}\right)}^{5} \cdot {\left({\left(\left|\color{blue}{\sqrt{x} \cdot \sqrt{x}}\right|\right)}^{\left(\frac{-1}{2}\right)}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   12. fabs-sqr 100.0%

       \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({x}^{-0.5}\right)}^{5} \cdot {\left({\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)}}^{\left(\frac{-1}{2}\right)}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   13. add-sqr-sqrt 100.0%

       \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({x}^{-0.5}\right)}^{5} \cdot {\left({\color{blue}{x}}^{\left(\frac{-1}{2}\right)}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   14. metadata-eval 100.0%

       \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({x}^{-0.5}\right)}^{5} \cdot {\left({x}^{\color{blue}{-0.5}}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

5. Applied egg-rr 100.0%

   \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \color{blue}{{\left({x}^{-0.5}\right)}^{5} \cdot {\left({x}^{-0.5}\right)}^{5}}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]
6. Step-by-step derivation

   1. pow-sqr 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \color{blue}{{\left({x}^{-0.5}\right)}^{\left(2 \cdot 5\right)}}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   2. metadata-eval 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left({x}^{-0.5}\right)}^{\color{blue}{10}}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

7. Simplified 100.0%

   \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \color{blue}{{\left({x}^{-0.5}\right)}^{10}}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]
8. Step-by-step derivation

   1. expm1-log1p-u 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left({\left({x}^{-0.5}\right)}^{10}\right)\right)}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   2. expm1-udef 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \color{blue}{e^{\mathsf{log1p}\left({\left({x}^{-0.5}\right)}^{10}\right)} - 1}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   3. log1p-udef 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, e^{\color{blue}{\log \left(1 + {\left({x}^{-0.5}\right)}^{10}\right)}} - 1, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   4. add-exp-log 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \color{blue}{\left(1 + {\left({x}^{-0.5}\right)}^{10}\right)} - 1, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   5. pow-pow 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \left(1 + \color{blue}{{x}^{\left(-0.5 \cdot 10\right)}}\right) - 1, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

   6. metadata-eval 100.0%

      \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \left(1 + {x}^{\color{blue}{-5}}\right) - 1, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

9. Applied egg-rr 100.0%

   \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \color{blue}{\left(1 + {x}^{-5}\right) - 1}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

10. Final simplification 100.0%

    \[\leadsto e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, \left(1 + {x}^{-5}\right) + -1, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}} \]

Alternative 3: 100.0% accurate, 2.7× speedup

Math

\[\begin{array}{l} \\ {\left(e^{x}\right)}^{x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \frac{1.875}{{x}^{7}} + \left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)\right) \cdot {\pi}^{-0.5}\right) \end{array} \]

FPCore

(FPCore (x)
 :precision binary64
 (*
  (pow (exp x) x)
  (*
   (fma
    0.75
    (pow x -5.0)
    (+ (/ 1.875 (pow x 7.0)) (+ (/ 1.0 x) (/ 0.5 (pow x 3.0)))))
   (pow PI -0.5))))

C

double code(double x) {
	return pow(exp(x), x) * (fma(0.75, pow(x, -5.0), ((1.875 / pow(x, 7.0)) + ((1.0 / x) + (0.5 / pow(x, 3.0))))) * pow(((double) M_PI), -0.5));
}

Julia

function code(x)
	return Float64((exp(x) ^ x) * Float64(fma(0.75, (x ^ -5.0), Float64(Float64(1.875 / (x ^ 7.0)) + Float64(Float64(1.0 / x) + Float64(0.5 / (x ^ 3.0))))) * (pi ^ -0.5)))
end

Wolfram

code[x_] := N[(N[Power[N[Exp[x], $MachinePrecision], x], $MachinePrecision] * N[(N[(0.75 * N[Power[x, -5.0], $MachinePrecision] + N[(N[(1.875 / N[Power[x, 7.0], $MachinePrecision]), $MachinePrecision] + N[(N[(1.0 / x), $MachinePrecision] + N[(0.5 / N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Power[Pi, -0.5], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 100.0%

   \[\left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(\frac{1}{\left|x\right|} + \frac{1}{2} \cdot \left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{3}{4} \cdot \left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{15}{8} \cdot \left(\left(\left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) \]

3. Simplified 100.0%

   \[\leadsto \color{blue}{e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}} \]
4. Step-by-step derivation

   1. div-inv 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right) \cdot \frac{1}{\sqrt{\pi}}\right)} \]

5. Applied egg-rr 100.0%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right) \cdot {\pi}^{-0.5}\right)} \]

6. Taylor expanded in x around 0 100.0%

   \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{0.5 \cdot \frac{1}{{x}^{3}} + \left(\frac{1}{x} + 1.875 \cdot \frac{1}{{x}^{7}}\right)}\right) \cdot {\pi}^{-0.5}\right) \]
7. Step-by-step derivation

   1. associate-+r+ 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{\left(0.5 \cdot \frac{1}{{x}^{3}} + \frac{1}{x}\right) + 1.875 \cdot \frac{1}{{x}^{7}}}\right) \cdot {\pi}^{-0.5}\right) \]

   2. +-commutative 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{1.875 \cdot \frac{1}{{x}^{7}} + \left(0.5 \cdot \frac{1}{{x}^{3}} + \frac{1}{x}\right)}\right) \cdot {\pi}^{-0.5}\right) \]

   3. associate-*r/ 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, 1.875 \cdot \frac{1}{{x}^{7}} + \left(\color{blue}{\frac{0.5 \cdot 1}{{x}^{3}}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   4. metadata-eval 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, 1.875 \cdot \frac{1}{{x}^{7}} + \left(\frac{\color{blue}{0.5}}{{x}^{3}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   5. associate-*r/ 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{\frac{1.875 \cdot 1}{{x}^{7}}} + \left(\frac{0.5}{{x}^{3}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   6. metadata-eval 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \frac{\color{blue}{1.875}}{{x}^{7}} + \left(\frac{0.5}{{x}^{3}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   7. +-commutative 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \frac{1.875}{{x}^{7}} + \color{blue}{\left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)}\right) \cdot {\pi}^{-0.5}\right) \]

8. Simplified 100.0%

   \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{\frac{1.875}{{x}^{7}} + \left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)}\right) \cdot {\pi}^{-0.5}\right) \]
9. Step-by-step derivation

   1. exp-prod 99.1%

      \[\leadsto \color{blue}{{\left(e^{x}\right)}^{x}} \cdot \frac{\sqrt{\frac{1}{\pi}}}{x} \]

10. Applied egg-rr 100.0%

    \[\leadsto \color{blue}{{\left(e^{x}\right)}^{x}} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \frac{1.875}{{x}^{7}} + \left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)\right) \cdot {\pi}^{-0.5}\right) \]

11. Final simplification 100.0%

    \[\leadsto {\left(e^{x}\right)}^{x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \frac{1.875}{{x}^{7}} + \left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)\right) \cdot {\pi}^{-0.5}\right) \]

Alternative 4: 100.0% accurate, 3.5× speedup

Math

\[\begin{array}{l} \\ e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right) + \left(\frac{1.875}{{x}^{7}} + \frac{0.75}{{x}^{5}}\right)\right)\right) \end{array} \]

FPCore

(FPCore (x)
 :precision binary64
 (*
  (exp (* x x))
  (*
   (sqrt (/ 1.0 PI))
   (+
    (+ (/ 1.0 x) (/ 0.5 (pow x 3.0)))
    (+ (/ 1.875 (pow x 7.0)) (/ 0.75 (pow x 5.0)))))))

C

double code(double x) {
	return exp((x * x)) * (sqrt((1.0 / ((double) M_PI))) * (((1.0 / x) + (0.5 / pow(x, 3.0))) + ((1.875 / pow(x, 7.0)) + (0.75 / pow(x, 5.0)))));
}

Java

public static double code(double x) {
	return Math.exp((x * x)) * (Math.sqrt((1.0 / Math.PI)) * (((1.0 / x) + (0.5 / Math.pow(x, 3.0))) + ((1.875 / Math.pow(x, 7.0)) + (0.75 / Math.pow(x, 5.0)))));
}

Python

def code(x):
	return math.exp((x * x)) * (math.sqrt((1.0 / math.pi)) * (((1.0 / x) + (0.5 / math.pow(x, 3.0))) + ((1.875 / math.pow(x, 7.0)) + (0.75 / math.pow(x, 5.0)))))

Julia

function code(x)
	return Float64(exp(Float64(x * x)) * Float64(sqrt(Float64(1.0 / pi)) * Float64(Float64(Float64(1.0 / x) + Float64(0.5 / (x ^ 3.0))) + Float64(Float64(1.875 / (x ^ 7.0)) + Float64(0.75 / (x ^ 5.0))))))
end

MATLAB

function tmp = code(x)
	tmp = exp((x * x)) * (sqrt((1.0 / pi)) * (((1.0 / x) + (0.5 / (x ^ 3.0))) + ((1.875 / (x ^ 7.0)) + (0.75 / (x ^ 5.0)))));
end

Wolfram

code[x_] := N[(N[Exp[N[(x * x), $MachinePrecision]], $MachinePrecision] * N[(N[Sqrt[N[(1.0 / Pi), $MachinePrecision]], $MachinePrecision] * N[(N[(N[(1.0 / x), $MachinePrecision] + N[(0.5 / N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(1.875 / N[Power[x, 7.0], $MachinePrecision]), $MachinePrecision] + N[(0.75 / N[Power[x, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 100.0%

   \[\left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(\frac{1}{\left|x\right|} + \frac{1}{2} \cdot \left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{3}{4} \cdot \left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{15}{8} \cdot \left(\left(\left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) \]

3. Simplified 100.0%

   \[\leadsto \color{blue}{e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}} \]
4. Step-by-step derivation

   1. div-inv 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right) \cdot \frac{1}{\sqrt{\pi}}\right)} \]

5. Applied egg-rr 100.0%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right) \cdot {\pi}^{-0.5}\right)} \]

6. Taylor expanded in x around 0 100.0%

   \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{0.5 \cdot \frac{1}{{x}^{3}} + \left(\frac{1}{x} + 1.875 \cdot \frac{1}{{x}^{7}}\right)}\right) \cdot {\pi}^{-0.5}\right) \]
7. Step-by-step derivation

   1. associate-+r+ 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{\left(0.5 \cdot \frac{1}{{x}^{3}} + \frac{1}{x}\right) + 1.875 \cdot \frac{1}{{x}^{7}}}\right) \cdot {\pi}^{-0.5}\right) \]

   2. +-commutative 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{1.875 \cdot \frac{1}{{x}^{7}} + \left(0.5 \cdot \frac{1}{{x}^{3}} + \frac{1}{x}\right)}\right) \cdot {\pi}^{-0.5}\right) \]

   3. associate-*r/ 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, 1.875 \cdot \frac{1}{{x}^{7}} + \left(\color{blue}{\frac{0.5 \cdot 1}{{x}^{3}}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   4. metadata-eval 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, 1.875 \cdot \frac{1}{{x}^{7}} + \left(\frac{\color{blue}{0.5}}{{x}^{3}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   5. associate-*r/ 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{\frac{1.875 \cdot 1}{{x}^{7}}} + \left(\frac{0.5}{{x}^{3}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   6. metadata-eval 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \frac{\color{blue}{1.875}}{{x}^{7}} + \left(\frac{0.5}{{x}^{3}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   7. +-commutative 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \frac{1.875}{{x}^{7}} + \color{blue}{\left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)}\right) \cdot {\pi}^{-0.5}\right) \]

8. Simplified 100.0%

   \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{\frac{1.875}{{x}^{7}} + \left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)}\right) \cdot {\pi}^{-0.5}\right) \]

9. Taylor expanded in x around 0 100.0%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(0.5 \cdot \left(\frac{1}{{x}^{3}} \cdot \sqrt{\frac{1}{\pi}}\right) + \left(0.75 \cdot \left(\frac{1}{{x}^{5}} \cdot \sqrt{\frac{1}{\pi}}\right) + \left(1.875 \cdot \left(\frac{1}{{x}^{7}} \cdot \sqrt{\frac{1}{\pi}}\right) + \frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)} \]
10. Step-by-step derivation

    1. +-commutative 100.0%

       \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\left(0.75 \cdot \left(\frac{1}{{x}^{5}} \cdot \sqrt{\frac{1}{\pi}}\right) + \left(1.875 \cdot \left(\frac{1}{{x}^{7}} \cdot \sqrt{\frac{1}{\pi}}\right) + \frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right)\right) + 0.5 \cdot \left(\frac{1}{{x}^{3}} \cdot \sqrt{\frac{1}{\pi}}\right)\right)} \]

    2. associate-+r+ 100.0%

       \[\leadsto e^{x \cdot x} \cdot \left(\color{blue}{\left(\left(0.75 \cdot \left(\frac{1}{{x}^{5}} \cdot \sqrt{\frac{1}{\pi}}\right) + 1.875 \cdot \left(\frac{1}{{x}^{7}} \cdot \sqrt{\frac{1}{\pi}}\right)\right) + \frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right)} + 0.5 \cdot \left(\frac{1}{{x}^{3}} \cdot \sqrt{\frac{1}{\pi}}\right)\right) \]

    3. associate-+l+ 100.0%

       \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\left(0.75 \cdot \left(\frac{1}{{x}^{5}} \cdot \sqrt{\frac{1}{\pi}}\right) + 1.875 \cdot \left(\frac{1}{{x}^{7}} \cdot \sqrt{\frac{1}{\pi}}\right)\right) + \left(\frac{1}{x} \cdot \sqrt{\frac{1}{\pi}} + 0.5 \cdot \left(\frac{1}{{x}^{3}} \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)} \]

11. Simplified 100.0%

    \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(\left(\frac{1.875}{{x}^{7}} + \frac{0.75}{{x}^{5}}\right) + \left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)\right)\right)} \]

12. Final simplification 100.0%

    \[\leadsto e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right) + \left(\frac{1.875}{{x}^{7}} + \frac{0.75}{{x}^{5}}\right)\right)\right) \]

Alternative 5: 99.7% accurate, 4.2× speedup

Math

\[\begin{array}{l} \\ e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\frac{1}{x} + \left(\frac{0.5}{{x}^{3}} + \frac{0.75}{{x}^{5}}\right)\right)\right) \end{array} \]

FPCore

(FPCore (x)
 :precision binary64
 (*
  (exp (* x x))
  (*
   (sqrt (/ 1.0 PI))
   (+ (/ 1.0 x) (+ (/ 0.5 (pow x 3.0)) (/ 0.75 (pow x 5.0)))))))

C

double code(double x) {
	return exp((x * x)) * (sqrt((1.0 / ((double) M_PI))) * ((1.0 / x) + ((0.5 / pow(x, 3.0)) + (0.75 / pow(x, 5.0)))));
}

Java

public static double code(double x) {
	return Math.exp((x * x)) * (Math.sqrt((1.0 / Math.PI)) * ((1.0 / x) + ((0.5 / Math.pow(x, 3.0)) + (0.75 / Math.pow(x, 5.0)))));
}

Python

def code(x):
	return math.exp((x * x)) * (math.sqrt((1.0 / math.pi)) * ((1.0 / x) + ((0.5 / math.pow(x, 3.0)) + (0.75 / math.pow(x, 5.0)))))

Julia

function code(x)
	return Float64(exp(Float64(x * x)) * Float64(sqrt(Float64(1.0 / pi)) * Float64(Float64(1.0 / x) + Float64(Float64(0.5 / (x ^ 3.0)) + Float64(0.75 / (x ^ 5.0))))))
end

MATLAB

function tmp = code(x)
	tmp = exp((x * x)) * (sqrt((1.0 / pi)) * ((1.0 / x) + ((0.5 / (x ^ 3.0)) + (0.75 / (x ^ 5.0)))));
end

Wolfram

code[x_] := N[(N[Exp[N[(x * x), $MachinePrecision]], $MachinePrecision] * N[(N[Sqrt[N[(1.0 / Pi), $MachinePrecision]], $MachinePrecision] * N[(N[(1.0 / x), $MachinePrecision] + N[(N[(0.5 / N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision] + N[(0.75 / N[Power[x, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 100.0%

   \[\left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(\frac{1}{\left|x\right|} + \frac{1}{2} \cdot \left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{3}{4} \cdot \left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{15}{8} \cdot \left(\left(\left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) \]

3. Simplified 100.0%

   \[\leadsto \color{blue}{e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}} \]
4. Step-by-step derivation

   1. div-inv 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right) \cdot \frac{1}{\sqrt{\pi}}\right)} \]

5. Applied egg-rr 100.0%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right) \cdot {\pi}^{-0.5}\right)} \]

6. Taylor expanded in x around 0 100.0%

   \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{0.5 \cdot \frac{1}{{x}^{3}} + \left(\frac{1}{x} + 1.875 \cdot \frac{1}{{x}^{7}}\right)}\right) \cdot {\pi}^{-0.5}\right) \]
7. Step-by-step derivation

   1. associate-+r+ 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{\left(0.5 \cdot \frac{1}{{x}^{3}} + \frac{1}{x}\right) + 1.875 \cdot \frac{1}{{x}^{7}}}\right) \cdot {\pi}^{-0.5}\right) \]

   2. +-commutative 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{1.875 \cdot \frac{1}{{x}^{7}} + \left(0.5 \cdot \frac{1}{{x}^{3}} + \frac{1}{x}\right)}\right) \cdot {\pi}^{-0.5}\right) \]

   3. associate-*r/ 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, 1.875 \cdot \frac{1}{{x}^{7}} + \left(\color{blue}{\frac{0.5 \cdot 1}{{x}^{3}}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   4. metadata-eval 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, 1.875 \cdot \frac{1}{{x}^{7}} + \left(\frac{\color{blue}{0.5}}{{x}^{3}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   5. associate-*r/ 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{\frac{1.875 \cdot 1}{{x}^{7}}} + \left(\frac{0.5}{{x}^{3}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   6. metadata-eval 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \frac{\color{blue}{1.875}}{{x}^{7}} + \left(\frac{0.5}{{x}^{3}} + \frac{1}{x}\right)\right) \cdot {\pi}^{-0.5}\right) \]

   7. +-commutative 100.0%

      \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \frac{1.875}{{x}^{7}} + \color{blue}{\left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)}\right) \cdot {\pi}^{-0.5}\right) \]

8. Simplified 100.0%

   \[\leadsto e^{x \cdot x} \cdot \left(\mathsf{fma}\left(0.75, {x}^{-5}, \color{blue}{\frac{1.875}{{x}^{7}} + \left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)}\right) \cdot {\pi}^{-0.5}\right) \]

9. Taylor expanded in x around inf 99.1%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(0.5 \cdot \left(\frac{1}{{x}^{3}} \cdot \sqrt{\frac{1}{\pi}}\right) + \left(0.75 \cdot \left(\frac{1}{{x}^{5}} \cdot \sqrt{\frac{1}{\pi}}\right) + \frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right)\right)} \]
10. Step-by-step derivation

    1. associate-+r+ 99.1%

       \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\left(0.5 \cdot \left(\frac{1}{{x}^{3}} \cdot \sqrt{\frac{1}{\pi}}\right) + 0.75 \cdot \left(\frac{1}{{x}^{5}} \cdot \sqrt{\frac{1}{\pi}}\right)\right) + \frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right)} \]

    2. +-commutative 99.1%

       \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\frac{1}{x} \cdot \sqrt{\frac{1}{\pi}} + \left(0.5 \cdot \left(\frac{1}{{x}^{3}} \cdot \sqrt{\frac{1}{\pi}}\right) + 0.75 \cdot \left(\frac{1}{{x}^{5}} \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right)} \]

    3. *-commutative 99.1%

       \[\leadsto e^{x \cdot x} \cdot \left(\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \frac{1}{x}} + \left(0.5 \cdot \left(\frac{1}{{x}^{3}} \cdot \sqrt{\frac{1}{\pi}}\right) + 0.75 \cdot \left(\frac{1}{{x}^{5}} \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right) \]

    4. associate-*r* 99.1%

       \[\leadsto e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \frac{1}{x} + \left(\color{blue}{\left(0.5 \cdot \frac{1}{{x}^{3}}\right) \cdot \sqrt{\frac{1}{\pi}}} + 0.75 \cdot \left(\frac{1}{{x}^{5}} \cdot \sqrt{\frac{1}{\pi}}\right)\right)\right) \]

    5. associate-*r* 99.1%

       \[\leadsto e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \frac{1}{x} + \left(\left(0.5 \cdot \frac{1}{{x}^{3}}\right) \cdot \sqrt{\frac{1}{\pi}} + \color{blue}{\left(0.75 \cdot \frac{1}{{x}^{5}}\right) \cdot \sqrt{\frac{1}{\pi}}}\right)\right) \]

    6. distribute-rgt-out 99.1%

       \[\leadsto e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \frac{1}{x} + \color{blue}{\sqrt{\frac{1}{\pi}} \cdot \left(0.5 \cdot \frac{1}{{x}^{3}} + 0.75 \cdot \frac{1}{{x}^{5}}\right)}\right) \]

    7. distribute-lft-out 99.1%

       \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(\frac{1}{x} + \left(0.5 \cdot \frac{1}{{x}^{3}} + 0.75 \cdot \frac{1}{{x}^{5}}\right)\right)\right)} \]

11. Simplified 99.1%

    \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(\frac{1}{x} + \left(\frac{0.5}{{x}^{3}} + \frac{0.75}{{x}^{5}}\right)\right)\right)} \]

12. Final simplification 99.1%

    \[\leadsto e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\frac{1}{x} + \left(\frac{0.5}{{x}^{3}} + \frac{0.75}{{x}^{5}}\right)\right)\right) \]

Alternative 6: 99.7% accurate, 5.3× speedup

Math

\[\begin{array}{l} \\ e^{x \cdot x} \cdot \left(\left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right) \cdot \sqrt{\frac{1}{\pi}}\right) \end{array} \]

FPCore

(FPCore (x)
 :precision binary64
 (* (exp (* x x)) (* (+ (/ 1.0 x) (/ 0.5 (pow x 3.0))) (sqrt (/ 1.0 PI)))))

C

double code(double x) {
	return exp((x * x)) * (((1.0 / x) + (0.5 / pow(x, 3.0))) * sqrt((1.0 / ((double) M_PI))));
}

Java

public static double code(double x) {
	return Math.exp((x * x)) * (((1.0 / x) + (0.5 / Math.pow(x, 3.0))) * Math.sqrt((1.0 / Math.PI)));
}

Python

def code(x):
	return math.exp((x * x)) * (((1.0 / x) + (0.5 / math.pow(x, 3.0))) * math.sqrt((1.0 / math.pi)))

Julia

function code(x)
	return Float64(exp(Float64(x * x)) * Float64(Float64(Float64(1.0 / x) + Float64(0.5 / (x ^ 3.0))) * sqrt(Float64(1.0 / pi))))
end

MATLAB

function tmp = code(x)
	tmp = exp((x * x)) * (((1.0 / x) + (0.5 / (x ^ 3.0))) * sqrt((1.0 / pi)));
end

Wolfram

code[x_] := N[(N[Exp[N[(x * x), $MachinePrecision]], $MachinePrecision] * N[(N[(N[(1.0 / x), $MachinePrecision] + N[(0.5 / N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Sqrt[N[(1.0 / Pi), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 100.0%

   \[\left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(\frac{1}{\left|x\right|} + \frac{1}{2} \cdot \left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{3}{4} \cdot \left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{15}{8} \cdot \left(\left(\left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) \]

3. Simplified 100.0%

   \[\leadsto \color{blue}{e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}} \]
4. Step-by-step derivation

   1. expm1-log1p-u 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}\right)\right)} \]

   2. expm1-udef 5.8%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}\right)} - 1\right)} \]

5. Applied egg-rr 5.8%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}\right)} - 1\right)} \]
6. Step-by-step derivation

   1. expm1-def 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}\right)\right)} \]

   2. expm1-log1p 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}} \]

7. Simplified 100.0%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}} \]

8. Taylor expanded in x around inf 99.1%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(0.5 \cdot \left(\frac{1}{{x}^{3}} \cdot \sqrt{\frac{1}{\pi}}\right) + \frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right)} \]
9. Step-by-step derivation

   1. associate-*r* 99.1%

      \[\leadsto e^{x \cdot x} \cdot \left(\color{blue}{\left(0.5 \cdot \frac{1}{{x}^{3}}\right) \cdot \sqrt{\frac{1}{\pi}}} + \frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right) \]

   2. distribute-rgt-out 99.1%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(0.5 \cdot \frac{1}{{x}^{3}} + \frac{1}{x}\right)\right)} \]

   3. +-commutative 99.1%

      \[\leadsto e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \color{blue}{\left(\frac{1}{x} + 0.5 \cdot \frac{1}{{x}^{3}}\right)}\right) \]

   4. associate-*r/ 99.1%

      \[\leadsto e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\frac{1}{x} + \color{blue}{\frac{0.5 \cdot 1}{{x}^{3}}}\right)\right) \]

   5. metadata-eval 99.1%

      \[\leadsto e^{x \cdot x} \cdot \left(\sqrt{\frac{1}{\pi}} \cdot \left(\frac{1}{x} + \frac{\color{blue}{0.5}}{{x}^{3}}\right)\right) \]

10. Simplified 99.1%

    \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\sqrt{\frac{1}{\pi}} \cdot \left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right)\right)} \]

11. Final simplification 99.1%

    \[\leadsto e^{x \cdot x} \cdot \left(\left(\frac{1}{x} + \frac{0.5}{{x}^{3}}\right) \cdot \sqrt{\frac{1}{\pi}}\right) \]

Alternative 7: 99.7% accurate, 7.1× speedup

Math

\[\begin{array}{l} \\ e^{x \cdot x} \cdot \frac{{\pi}^{-0.5}}{x} \end{array} \]

FPCore

(FPCore (x) :precision binary64 (* (exp (* x x)) (/ (pow PI -0.5) x)))

C

double code(double x) {
	return exp((x * x)) * (pow(((double) M_PI), -0.5) / x);
}

Java

public static double code(double x) {
	return Math.exp((x * x)) * (Math.pow(Math.PI, -0.5) / x);
}

Python

def code(x):
	return math.exp((x * x)) * (math.pow(math.pi, -0.5) / x)

Julia

function code(x)
	return Float64(exp(Float64(x * x)) * Float64((pi ^ -0.5) / x))
end

MATLAB

function tmp = code(x)
	tmp = exp((x * x)) * ((pi ^ -0.5) / x);
end

Wolfram

code[x_] := N[(N[Exp[N[(x * x), $MachinePrecision]], $MachinePrecision] * N[(N[Power[Pi, -0.5], $MachinePrecision] / x), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 100.0%

   \[\left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(\frac{1}{\left|x\right|} + \frac{1}{2} \cdot \left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{3}{4} \cdot \left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{15}{8} \cdot \left(\left(\left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) \]

3. Simplified 100.0%

   \[\leadsto \color{blue}{e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}} \]
4. Step-by-step derivation

   1. expm1-log1p-u 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}\right)\right)} \]

   2. expm1-udef 5.8%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}\right)} - 1\right)} \]

5. Applied egg-rr 5.8%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}\right)} - 1\right)} \]
6. Step-by-step derivation

   1. expm1-def 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}\right)\right)} \]

   2. expm1-log1p 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}} \]

7. Simplified 100.0%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}} \]

8. Taylor expanded in x around inf 99.1%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right)} \]
9. Step-by-step derivation

   1. associate-*l/ 99.1%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{1 \cdot \sqrt{\frac{1}{\pi}}}{x}} \]

   2. *-lft-identity 99.1%

      \[\leadsto e^{x \cdot x} \cdot \frac{\color{blue}{\sqrt{\frac{1}{\pi}}}}{x} \]

10. Simplified 99.1%

    \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\sqrt{\frac{1}{\pi}}}{x}} \]
11. Step-by-step derivation

    1. expm1-log1p-u 99.1%

       \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\sqrt{\frac{1}{\pi}}}{x}\right)\right)} \]

    2. expm1-udef 4.9%

       \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\sqrt{\frac{1}{\pi}}}{x}\right)} - 1\right)} \]

    3. div-inv 4.9%

       \[\leadsto e^{x \cdot x} \cdot \left(e^{\mathsf{log1p}\left(\color{blue}{\sqrt{\frac{1}{\pi}} \cdot \frac{1}{x}}\right)} - 1\right) \]

    4. div-inv 4.9%

       \[\leadsto e^{x \cdot x} \cdot \left(e^{\mathsf{log1p}\left(\color{blue}{\frac{\sqrt{\frac{1}{\pi}}}{x}}\right)} - 1\right) \]

    5. inv-pow 4.9%

       \[\leadsto e^{x \cdot x} \cdot \left(e^{\mathsf{log1p}\left(\frac{\sqrt{\color{blue}{{\pi}^{-1}}}}{x}\right)} - 1\right) \]

    6. sqrt-pow1 4.9%

       \[\leadsto e^{x \cdot x} \cdot \left(e^{\mathsf{log1p}\left(\frac{\color{blue}{{\pi}^{\left(\frac{-1}{2}\right)}}}{x}\right)} - 1\right) \]

    7. metadata-eval 4.9%

       \[\leadsto e^{x \cdot x} \cdot \left(e^{\mathsf{log1p}\left(\frac{{\pi}^{\color{blue}{-0.5}}}{x}\right)} - 1\right) \]

12. Applied egg-rr 4.9%

    \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{{\pi}^{-0.5}}{x}\right)} - 1\right)} \]
13. Step-by-step derivation

    1. expm1-def 99.1%

       \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{{\pi}^{-0.5}}{x}\right)\right)} \]

    2. expm1-log1p 99.1%

       \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{{\pi}^{-0.5}}{x}} \]

14. Simplified 99.1%

    \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{{\pi}^{-0.5}}{x}} \]

15. Final simplification 99.1%

    \[\leadsto e^{x \cdot x} \cdot \frac{{\pi}^{-0.5}}{x} \]

Alternative 8: 5.4% accurate, 10.5× speedup

Math

\[\begin{array}{l} \\ \sqrt{\frac{1}{\pi}} \cdot \left(x + \frac{1}{x}\right) \end{array} \]

FPCore

(FPCore (x) :precision binary64 (* (sqrt (/ 1.0 PI)) (+ x (/ 1.0 x))))

C

double code(double x) {
	return sqrt((1.0 / ((double) M_PI))) * (x + (1.0 / x));
}

Java

public static double code(double x) {
	return Math.sqrt((1.0 / Math.PI)) * (x + (1.0 / x));
}

Python

def code(x):
	return math.sqrt((1.0 / math.pi)) * (x + (1.0 / x))

Julia

function code(x)
	return Float64(sqrt(Float64(1.0 / pi)) * Float64(x + Float64(1.0 / x)))
end

MATLAB

function tmp = code(x)
	tmp = sqrt((1.0 / pi)) * (x + (1.0 / x));
end

Wolfram

code[x_] := N[(N[Sqrt[N[(1.0 / Pi), $MachinePrecision]], $MachinePrecision] * N[(x + N[(1.0 / x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]

Derivation

1. Initial program 100.0%

   \[\left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(\frac{1}{\left|x\right|} + \frac{1}{2} \cdot \left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{3}{4} \cdot \left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{15}{8} \cdot \left(\left(\left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) \]

3. Simplified 100.0%

   \[\leadsto \color{blue}{e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}} \]
4. Step-by-step derivation

   1. expm1-log1p-u 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}\right)\right)} \]

   2. expm1-udef 5.8%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}\right)} - 1\right)} \]

5. Applied egg-rr 5.8%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}\right)} - 1\right)} \]
6. Step-by-step derivation

   1. expm1-def 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}\right)\right)} \]

   2. expm1-log1p 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}} \]

7. Simplified 100.0%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}} \]

8. Taylor expanded in x around inf 99.1%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right)} \]
9. Step-by-step derivation

   1. associate-*l/ 99.1%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{1 \cdot \sqrt{\frac{1}{\pi}}}{x}} \]

   2. *-lft-identity 99.1%

      \[\leadsto e^{x \cdot x} \cdot \frac{\color{blue}{\sqrt{\frac{1}{\pi}}}}{x} \]

10. Simplified 99.1%

    \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\sqrt{\frac{1}{\pi}}}{x}} \]

11. Taylor expanded in x around 0 5.7%

    \[\leadsto \color{blue}{x \cdot \sqrt{\frac{1}{\pi}} + \frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}} \]
12. Step-by-step derivation

    1. distribute-rgt-out 5.7%

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

13. Simplified 5.7%

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

14. Final simplification 5.7%

    \[\leadsto \sqrt{\frac{1}{\pi}} \cdot \left(x + \frac{1}{x}\right) \]

Alternative 9: 2.3% accurate, 10.7× speedup

Math

\[\begin{array}{l} \\ \frac{\sqrt{\frac{1}{\pi}}}{x} \end{array} \]

FPCore

(FPCore (x) :precision binary64 (/ (sqrt (/ 1.0 PI)) x))

C

double code(double x) {
	return sqrt((1.0 / ((double) M_PI))) / x;
}

Java

public static double code(double x) {
	return Math.sqrt((1.0 / Math.PI)) / x;
}

Python

def code(x):
	return math.sqrt((1.0 / math.pi)) / x

Julia

function code(x)
	return Float64(sqrt(Float64(1.0 / pi)) / x)
end

MATLAB

function tmp = code(x)
	tmp = sqrt((1.0 / pi)) / x;
end

Wolfram

code[x_] := N[(N[Sqrt[N[(1.0 / Pi), $MachinePrecision]], $MachinePrecision] / x), $MachinePrecision]

Derivation

1. Initial program 100.0%

   \[\left(\frac{1}{\sqrt{\pi}} \cdot e^{\left|x\right| \cdot \left|x\right|}\right) \cdot \left(\left(\left(\frac{1}{\left|x\right|} + \frac{1}{2} \cdot \left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{3}{4} \cdot \left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) + \frac{15}{8} \cdot \left(\left(\left(\left(\left(\left(\frac{1}{\left|x\right|} \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right) \cdot \frac{1}{\left|x\right|}\right)\right) \]

3. Simplified 100.0%

   \[\leadsto \color{blue}{e^{x \cdot x} \cdot \frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}} \]
4. Step-by-step derivation

   1. expm1-log1p-u 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}\right)\right)} \]

   2. expm1-udef 5.8%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {\left(\frac{1}{\left|x\right|}\right)}^{5}, \mathsf{fma}\left(1.875, {\left(\frac{1}{\left|x\right|}\right)}^{7}, \frac{1 + \frac{0.5}{x \cdot x}}{\left|x\right|}\right)\right)}{\sqrt{\pi}}\right)} - 1\right)} \]

5. Applied egg-rr 5.8%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(e^{\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}\right)} - 1\right)} \]
6. Step-by-step derivation

   1. expm1-def 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}\right)\right)} \]

   2. expm1-log1p 100.0%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}} \]

7. Simplified 100.0%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\mathsf{fma}\left(0.75, {x}^{-5}, \mathsf{fma}\left(1.875, {x}^{-7}, \frac{\mathsf{fma}\left(0.5, {x}^{-2}, 1\right)}{x}\right)\right)}{\sqrt{\pi}}} \]

8. Taylor expanded in x around inf 99.1%

   \[\leadsto e^{x \cdot x} \cdot \color{blue}{\left(\frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}\right)} \]
9. Step-by-step derivation

   1. associate-*l/ 99.1%

      \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{1 \cdot \sqrt{\frac{1}{\pi}}}{x}} \]

   2. *-lft-identity 99.1%

      \[\leadsto e^{x \cdot x} \cdot \frac{\color{blue}{\sqrt{\frac{1}{\pi}}}}{x} \]

10. Simplified 99.1%

    \[\leadsto e^{x \cdot x} \cdot \color{blue}{\frac{\sqrt{\frac{1}{\pi}}}{x}} \]
11. Step-by-step derivation

    1. exp-prod 99.1%

       \[\leadsto \color{blue}{{\left(e^{x}\right)}^{x}} \cdot \frac{\sqrt{\frac{1}{\pi}}}{x} \]

12. Applied egg-rr 99.1%

    \[\leadsto \color{blue}{{\left(e^{x}\right)}^{x}} \cdot \frac{\sqrt{\frac{1}{\pi}}}{x} \]

13. Taylor expanded in x around 0 2.4%

    \[\leadsto \color{blue}{\frac{1}{x} \cdot \sqrt{\frac{1}{\pi}}} \]
14. Step-by-step derivation

    1. associate-*l/ 2.4%

       \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{\frac{1}{\pi}}}{x}} \]

    2. *-lft-identity 2.4%

       \[\leadsto \frac{\color{blue}{\sqrt{\frac{1}{\pi}}}}{x} \]

15. Simplified 2.4%

    \[\leadsto \color{blue}{\frac{\sqrt{\frac{1}{\pi}}}{x}} \]

16. Final simplification 2.4%

    \[\leadsto \frac{\sqrt{\frac{1}{\pi}}}{x} \]

Reproduce

herbie shell --seed 2023319 
(FPCore (x)
  :name "Jmat.Real.erfi, branch x greater than or equal to 5"
  :precision binary64
  :pre (>= x 0.5)
  (* (* (/ 1.0 (sqrt PI)) (exp (* (fabs x) (fabs x)))) (+ (+ (+ (/ 1.0 (fabs x)) (* (/ 1.0 2.0) (* (* (/ 1.0 (fabs x)) (/ 1.0 (fabs x))) (/ 1.0 (fabs x))))) (* (/ 3.0 4.0) (* (* (* (* (/ 1.0 (fabs x)) (/ 1.0 (fabs x))) (/ 1.0 (fabs x))) (/ 1.0 (fabs x))) (/ 1.0 (fabs x))))) (* (/ 15.0 8.0) (* (* (* (* (* (* (/ 1.0 (fabs x)) (/ 1.0 (fabs x))) (/ 1.0 (fabs x))) (/ 1.0 (fabs x))) (/ 1.0 (fabs x))) (/ 1.0 (fabs x))) (/ 1.0 (fabs x)))))))