Migdal et al, Equation (51)

Percentage Accurate: 99.4% → 99.5%
Time: 10.4s
Alternatives: 8
Speedup: 1.1×

Specification

?
\[\begin{array}{l} \\ \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \end{array} \]
(FPCore (k n)
 :precision binary64
 (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))
double code(double k, double n) {
	return (1.0 / sqrt(k)) * pow(((2.0 * ((double) M_PI)) * n), ((1.0 - k) / 2.0));
}
public static double code(double k, double n) {
	return (1.0 / Math.sqrt(k)) * Math.pow(((2.0 * Math.PI) * n), ((1.0 - k) / 2.0));
}
def code(k, n):
	return (1.0 / math.sqrt(k)) * math.pow(((2.0 * math.pi) * n), ((1.0 - k) / 2.0))
function code(k, n)
	return Float64(Float64(1.0 / sqrt(k)) * (Float64(Float64(2.0 * pi) * n) ^ Float64(Float64(1.0 - k) / 2.0)))
end
function tmp = code(k, n)
	tmp = (1.0 / sqrt(k)) * (((2.0 * pi) * n) ^ ((1.0 - k) / 2.0));
end
code[k_, n_] := N[(N[(1.0 / N[Sqrt[k], $MachinePrecision]), $MachinePrecision] * N[Power[N[(N[(2.0 * Pi), $MachinePrecision] * n), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

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

Accuracy vs Speed?

Herbie found 8 alternatives:

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

Initial Program: 99.4% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \end{array} \]
(FPCore (k n)
 :precision binary64
 (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))
double code(double k, double n) {
	return (1.0 / sqrt(k)) * pow(((2.0 * ((double) M_PI)) * n), ((1.0 - k) / 2.0));
}
public static double code(double k, double n) {
	return (1.0 / Math.sqrt(k)) * Math.pow(((2.0 * Math.PI) * n), ((1.0 - k) / 2.0));
}
def code(k, n):
	return (1.0 / math.sqrt(k)) * math.pow(((2.0 * math.pi) * n), ((1.0 - k) / 2.0))
function code(k, n)
	return Float64(Float64(1.0 / sqrt(k)) * (Float64(Float64(2.0 * pi) * n) ^ Float64(Float64(1.0 - k) / 2.0)))
end
function tmp = code(k, n)
	tmp = (1.0 / sqrt(k)) * (((2.0 * pi) * n) ^ ((1.0 - k) / 2.0));
end
code[k_, n_] := N[(N[(1.0 / N[Sqrt[k], $MachinePrecision]), $MachinePrecision] * N[Power[N[(N[(2.0 * Pi), $MachinePrecision] * n), $MachinePrecision], N[(N[(1.0 - k), $MachinePrecision] / 2.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}
\end{array}

Alternative 1: 99.5% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \pi \cdot \left(2 \cdot n\right)\\ \frac{\sqrt{t\_0}}{\sqrt{k \cdot {t\_0}^{k}}} \end{array} \end{array} \]
(FPCore (k n)
 :precision binary64
 (let* ((t_0 (* PI (* 2.0 n)))) (/ (sqrt t_0) (sqrt (* k (pow t_0 k))))))
double code(double k, double n) {
	double t_0 = ((double) M_PI) * (2.0 * n);
	return sqrt(t_0) / sqrt((k * pow(t_0, k)));
}
public static double code(double k, double n) {
	double t_0 = Math.PI * (2.0 * n);
	return Math.sqrt(t_0) / Math.sqrt((k * Math.pow(t_0, k)));
}
def code(k, n):
	t_0 = math.pi * (2.0 * n)
	return math.sqrt(t_0) / math.sqrt((k * math.pow(t_0, k)))
function code(k, n)
	t_0 = Float64(pi * Float64(2.0 * n))
	return Float64(sqrt(t_0) / sqrt(Float64(k * (t_0 ^ k))))
end
function tmp = code(k, n)
	t_0 = pi * (2.0 * n);
	tmp = sqrt(t_0) / sqrt((k * (t_0 ^ k)));
end
code[k_, n_] := Block[{t$95$0 = N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision]}, N[(N[Sqrt[t$95$0], $MachinePrecision] / N[Sqrt[N[(k * N[Power[t$95$0, k], $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \pi \cdot \left(2 \cdot n\right)\\
\frac{\sqrt{t\_0}}{\sqrt{k \cdot {t\_0}^{k}}}
\end{array}
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \color{blue}{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
    2. un-div-invN/A

      \[\leadsto \color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
    3. div-subN/A

      \[\leadsto \frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\color{blue}{\left(\frac{1}{2} - \frac{k}{2}\right)}}}{\sqrt{k}} \]
    4. metadata-evalN/A

      \[\leadsto \frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\color{blue}{\frac{1}{2}} - \frac{k}{2}\right)}}{\sqrt{k}} \]
    5. pow-subN/A

      \[\leadsto \frac{\color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\frac{1}{2}}}{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}}}{\sqrt{k}} \]
    6. associate-/l/N/A

      \[\leadsto \color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\frac{1}{2}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\frac{1}{2}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}} \]
    8. unpow1/2N/A

      \[\leadsto \frac{\color{blue}{\sqrt{\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    9. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \frac{\color{blue}{\sqrt{\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    10. associate-*l*N/A

      \[\leadsto \frac{\sqrt{\color{blue}{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    11. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{\color{blue}{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    12. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    13. PI-lowering-PI.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \left(\color{blue}{\mathsf{PI}\left(\right)} \cdot n\right)}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    14. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\color{blue}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}} \]
    15. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\color{blue}{\sqrt{k}} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    16. pow-lowering-pow.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\sqrt{k} \cdot \color{blue}{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}} \]
  4. Applied egg-rr99.7%

    \[\leadsto \color{blue}{\frac{\sqrt{2 \cdot \left(\pi \cdot n\right)}}{\sqrt{k} \cdot {\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(k \cdot 0.5\right)}}} \]
  5. Step-by-step derivation
    1. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}}} \]
    2. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \frac{\color{blue}{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    3. *-commutativeN/A

      \[\leadsto \frac{\sqrt{2 \cdot \color{blue}{\left(n \cdot \mathsf{PI}\left(\right)\right)}}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    4. associate-*r*N/A

      \[\leadsto \frac{\sqrt{\color{blue}{\left(2 \cdot n\right) \cdot \mathsf{PI}\left(\right)}}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    5. metadata-evalN/A

      \[\leadsto \frac{\sqrt{\left(\color{blue}{\frac{-2}{-1}} \cdot n\right) \cdot \mathsf{PI}\left(\right)}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    6. associate-/r/N/A

      \[\leadsto \frac{\sqrt{\color{blue}{\frac{-2}{\frac{-1}{n}}} \cdot \mathsf{PI}\left(\right)}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    7. *-commutativeN/A

      \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    8. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    9. PI-lowering-PI.f64N/A

      \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right)} \cdot \frac{-2}{\frac{-1}{n}}}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    10. associate-/r/N/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(\frac{-2}{-1} \cdot n\right)}}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    11. metadata-evalN/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(\color{blue}{2} \cdot n\right)}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    12. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(2 \cdot n\right)}}}{\sqrt{k} \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}} \]
    13. pow-unpowN/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(2 \cdot n\right)}}{\sqrt{k} \cdot \color{blue}{{\left({\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{k}\right)}^{\frac{1}{2}}}} \]
    14. unpow1/2N/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(2 \cdot n\right)}}{\sqrt{k} \cdot \color{blue}{\sqrt{{\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{k}}}} \]
    15. sqrt-unprodN/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(2 \cdot n\right)}}{\color{blue}{\sqrt{k \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{k}}}} \]
    16. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(2 \cdot n\right)}}{\color{blue}{\sqrt{k \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{k}}}} \]
    17. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(2 \cdot n\right)}}{\sqrt{\color{blue}{k \cdot {\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{k}}}} \]
    18. pow-lowering-pow.f64N/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(2 \cdot n\right)}}{\sqrt{k \cdot \color{blue}{{\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{k}}}} \]
  6. Applied egg-rr99.7%

    \[\leadsto \color{blue}{\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\sqrt{k \cdot {\left(\pi \cdot \left(2 \cdot n\right)\right)}^{k}}}} \]
  7. Add Preprocessing

Alternative 2: 98.1% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;k \leq 1:\\ \;\;\;\;\sqrt{\frac{\pi}{k}} \cdot \sqrt{2 \cdot n}\\ \mathbf{else}:\\ \;\;\;\;\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(k \cdot -0.5\right)}}{\sqrt{k}}\\ \end{array} \end{array} \]
(FPCore (k n)
 :precision binary64
 (if (<= k 1.0)
   (* (sqrt (/ PI k)) (sqrt (* 2.0 n)))
   (/ (pow (* PI (* 2.0 n)) (* k -0.5)) (sqrt k))))
double code(double k, double n) {
	double tmp;
	if (k <= 1.0) {
		tmp = sqrt((((double) M_PI) / k)) * sqrt((2.0 * n));
	} else {
		tmp = pow((((double) M_PI) * (2.0 * n)), (k * -0.5)) / sqrt(k);
	}
	return tmp;
}
public static double code(double k, double n) {
	double tmp;
	if (k <= 1.0) {
		tmp = Math.sqrt((Math.PI / k)) * Math.sqrt((2.0 * n));
	} else {
		tmp = Math.pow((Math.PI * (2.0 * n)), (k * -0.5)) / Math.sqrt(k);
	}
	return tmp;
}
def code(k, n):
	tmp = 0
	if k <= 1.0:
		tmp = math.sqrt((math.pi / k)) * math.sqrt((2.0 * n))
	else:
		tmp = math.pow((math.pi * (2.0 * n)), (k * -0.5)) / math.sqrt(k)
	return tmp
function code(k, n)
	tmp = 0.0
	if (k <= 1.0)
		tmp = Float64(sqrt(Float64(pi / k)) * sqrt(Float64(2.0 * n)));
	else
		tmp = Float64((Float64(pi * Float64(2.0 * n)) ^ Float64(k * -0.5)) / sqrt(k));
	end
	return tmp
end
function tmp_2 = code(k, n)
	tmp = 0.0;
	if (k <= 1.0)
		tmp = sqrt((pi / k)) * sqrt((2.0 * n));
	else
		tmp = ((pi * (2.0 * n)) ^ (k * -0.5)) / sqrt(k);
	end
	tmp_2 = tmp;
end
code[k_, n_] := If[LessEqual[k, 1.0], N[(N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(2.0 * n), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[(N[Power[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision], N[(k * -0.5), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;k \leq 1:\\
\;\;\;\;\sqrt{\frac{\pi}{k}} \cdot \sqrt{2 \cdot n}\\

\mathbf{else}:\\
\;\;\;\;\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(k \cdot -0.5\right)}}{\sqrt{k}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if k < 1

    1. Initial program 99.2%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in k around 0

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
      2. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
      3. /-lowering-/.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \sqrt{\frac{\color{blue}{n \cdot \mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
      5. PI-lowering-PI.f64N/A

        \[\leadsto \sqrt{\frac{n \cdot \color{blue}{\mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
      6. sqrt-lowering-sqrt.f6475.3

        \[\leadsto \sqrt{\frac{n \cdot \pi}{k}} \cdot \color{blue}{\sqrt{2}} \]
    5. Simplified75.3%

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2}} \]
    6. Step-by-step derivation
      1. sqrt-unprodN/A

        \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k} \cdot 2}} \]
      2. associate-*l/N/A

        \[\leadsto \sqrt{\color{blue}{\frac{\left(n \cdot \mathsf{PI}\left(\right)\right) \cdot 2}{k}}} \]
      3. *-commutativeN/A

        \[\leadsto \sqrt{\frac{\color{blue}{2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)}}{k}} \]
      4. *-commutativeN/A

        \[\leadsto \sqrt{\frac{2 \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot n\right)}}{k}} \]
      5. sqrt-undivN/A

        \[\leadsto \color{blue}{\frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\sqrt{k}}} \]
      6. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\sqrt{k}}} \]
      7. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \frac{\color{blue}{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k}} \]
      8. *-commutativeN/A

        \[\leadsto \frac{\sqrt{2 \cdot \color{blue}{\left(n \cdot \mathsf{PI}\left(\right)\right)}}}{\sqrt{k}} \]
      9. associate-*r*N/A

        \[\leadsto \frac{\sqrt{\color{blue}{\left(2 \cdot n\right) \cdot \mathsf{PI}\left(\right)}}}{\sqrt{k}} \]
      10. metadata-evalN/A

        \[\leadsto \frac{\sqrt{\left(\color{blue}{\frac{-2}{-1}} \cdot n\right) \cdot \mathsf{PI}\left(\right)}}{\sqrt{k}} \]
      11. associate-/r/N/A

        \[\leadsto \frac{\sqrt{\color{blue}{\frac{-2}{\frac{-1}{n}}} \cdot \mathsf{PI}\left(\right)}}{\sqrt{k}} \]
      12. *-commutativeN/A

        \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}}{\sqrt{k}} \]
      13. *-lowering-*.f64N/A

        \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}}{\sqrt{k}} \]
      14. PI-lowering-PI.f64N/A

        \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right)} \cdot \frac{-2}{\frac{-1}{n}}}}{\sqrt{k}} \]
      15. associate-/r/N/A

        \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(\frac{-2}{-1} \cdot n\right)}}}{\sqrt{k}} \]
      16. metadata-evalN/A

        \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(\color{blue}{2} \cdot n\right)}}{\sqrt{k}} \]
      17. *-lowering-*.f64N/A

        \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(2 \cdot n\right)}}}{\sqrt{k}} \]
      18. sqrt-lowering-sqrt.f6498.4

        \[\leadsto \frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\color{blue}{\sqrt{k}}} \]
    7. Applied egg-rr98.4%

      \[\leadsto \color{blue}{\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\sqrt{k}}} \]
    8. Step-by-step derivation
      1. sqrt-prodN/A

        \[\leadsto \frac{\color{blue}{\sqrt{\mathsf{PI}\left(\right)} \cdot \sqrt{2 \cdot n}}}{\sqrt{k}} \]
      2. pow1/2N/A

        \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right)} \cdot \color{blue}{{\left(2 \cdot n\right)}^{\frac{1}{2}}}}{\sqrt{k}} \]
      3. associate-*l/N/A

        \[\leadsto \color{blue}{\frac{\sqrt{\mathsf{PI}\left(\right)}}{\sqrt{k}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}}} \]
      4. sqrt-divN/A

        \[\leadsto \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k}}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}}} \]
      6. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k}}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
      7. /-lowering-/.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{\mathsf{PI}\left(\right)}{k}}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
      8. PI-lowering-PI.f64N/A

        \[\leadsto \sqrt{\frac{\color{blue}{\mathsf{PI}\left(\right)}}{k}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
      9. pow1/2N/A

        \[\leadsto \sqrt{\frac{\mathsf{PI}\left(\right)}{k}} \cdot \color{blue}{\sqrt{2 \cdot n}} \]
      10. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{PI}\left(\right)}{k}} \cdot \color{blue}{\sqrt{2 \cdot n}} \]
      11. *-lowering-*.f6498.5

        \[\leadsto \sqrt{\frac{\pi}{k}} \cdot \sqrt{\color{blue}{2 \cdot n}} \]
    9. Applied egg-rr98.5%

      \[\leadsto \color{blue}{\sqrt{\frac{\pi}{k}} \cdot \sqrt{2 \cdot n}} \]

    if 1 < k

    1. Initial program 100.0%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in k around inf

      \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\color{blue}{\left(\frac{-1}{2} \cdot k\right)}} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64100.0

        \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\left(-0.5 \cdot k\right)}} \]
    5. Simplified100.0%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\left(-0.5 \cdot k\right)}} \]
    6. Step-by-step derivation
      1. *-commutativeN/A

        \[\leadsto \color{blue}{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{-1}{2} \cdot k\right)} \cdot \frac{1}{\sqrt{k}}} \]
      2. un-div-invN/A

        \[\leadsto \color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}}} \]
      3. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}}} \]
      4. associate-*r*N/A

        \[\leadsto \frac{{\color{blue}{\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      5. pow-lowering-pow.f64N/A

        \[\leadsto \frac{\color{blue}{{\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(\frac{-1}{2} \cdot k\right)}}}{\sqrt{k}} \]
      6. *-commutativeN/A

        \[\leadsto \frac{{\left(2 \cdot \color{blue}{\left(n \cdot \mathsf{PI}\left(\right)\right)}\right)}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      7. associate-*r*N/A

        \[\leadsto \frac{{\color{blue}{\left(\left(2 \cdot n\right) \cdot \mathsf{PI}\left(\right)\right)}}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      8. metadata-evalN/A

        \[\leadsto \frac{{\left(\left(\color{blue}{\frac{-2}{-1}} \cdot n\right) \cdot \mathsf{PI}\left(\right)\right)}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      9. associate-/r/N/A

        \[\leadsto \frac{{\left(\color{blue}{\frac{-2}{\frac{-1}{n}}} \cdot \mathsf{PI}\left(\right)\right)}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      10. *-commutativeN/A

        \[\leadsto \frac{{\color{blue}{\left(\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}\right)}}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      11. *-lowering-*.f64N/A

        \[\leadsto \frac{{\color{blue}{\left(\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}\right)}}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      12. PI-lowering-PI.f64N/A

        \[\leadsto \frac{{\left(\color{blue}{\mathsf{PI}\left(\right)} \cdot \frac{-2}{\frac{-1}{n}}\right)}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      13. associate-/r/N/A

        \[\leadsto \frac{{\left(\mathsf{PI}\left(\right) \cdot \color{blue}{\left(\frac{-2}{-1} \cdot n\right)}\right)}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      14. metadata-evalN/A

        \[\leadsto \frac{{\left(\mathsf{PI}\left(\right) \cdot \left(\color{blue}{2} \cdot n\right)\right)}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      15. *-lowering-*.f64N/A

        \[\leadsto \frac{{\left(\mathsf{PI}\left(\right) \cdot \color{blue}{\left(2 \cdot n\right)}\right)}^{\left(\frac{-1}{2} \cdot k\right)}}{\sqrt{k}} \]
      16. *-commutativeN/A

        \[\leadsto \frac{{\left(\mathsf{PI}\left(\right) \cdot \left(2 \cdot n\right)\right)}^{\color{blue}{\left(k \cdot \frac{-1}{2}\right)}}}{\sqrt{k}} \]
      17. *-lowering-*.f64N/A

        \[\leadsto \frac{{\left(\mathsf{PI}\left(\right) \cdot \left(2 \cdot n\right)\right)}^{\color{blue}{\left(k \cdot \frac{-1}{2}\right)}}}{\sqrt{k}} \]
      18. sqrt-lowering-sqrt.f64100.0

        \[\leadsto \frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(k \cdot -0.5\right)}}{\color{blue}{\sqrt{k}}} \]
    7. Applied egg-rr100.0%

      \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(k \cdot -0.5\right)}}{\sqrt{k}}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 3: 99.4% accurate, 1.1× speedup?

\[\begin{array}{l} \\ \frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\mathsf{fma}\left(k, -0.5, 0.5\right)\right)}}{\sqrt{k}} \end{array} \]
(FPCore (k n)
 :precision binary64
 (/ (pow (* PI (* 2.0 n)) (fma k -0.5 0.5)) (sqrt k)))
double code(double k, double n) {
	return pow((((double) M_PI) * (2.0 * n)), fma(k, -0.5, 0.5)) / sqrt(k);
}
function code(k, n)
	return Float64((Float64(pi * Float64(2.0 * n)) ^ fma(k, -0.5, 0.5)) / sqrt(k))
end
code[k_, n_] := N[(N[Power[N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision], N[(k * -0.5 + 0.5), $MachinePrecision]], $MachinePrecision] / N[Sqrt[k], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\mathsf{fma}\left(k, -0.5, 0.5\right)\right)}}{\sqrt{k}}
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \color{blue}{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \cdot \frac{1}{\sqrt{k}}} \]
    2. un-div-invN/A

      \[\leadsto \color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)}}{\sqrt{k}}} \]
    3. div-subN/A

      \[\leadsto \frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\color{blue}{\left(\frac{1}{2} - \frac{k}{2}\right)}}}{\sqrt{k}} \]
    4. metadata-evalN/A

      \[\leadsto \frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\color{blue}{\frac{1}{2}} - \frac{k}{2}\right)}}{\sqrt{k}} \]
    5. pow-subN/A

      \[\leadsto \frac{\color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\frac{1}{2}}}{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}}}{\sqrt{k}} \]
    6. associate-/l/N/A

      \[\leadsto \color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\frac{1}{2}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\frac{1}{2}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}} \]
    8. unpow1/2N/A

      \[\leadsto \frac{\color{blue}{\sqrt{\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    9. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \frac{\color{blue}{\sqrt{\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    10. associate-*l*N/A

      \[\leadsto \frac{\sqrt{\color{blue}{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    11. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{\color{blue}{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    12. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    13. PI-lowering-PI.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \left(\color{blue}{\mathsf{PI}\left(\right)} \cdot n\right)}}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    14. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\color{blue}{\sqrt{k} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}} \]
    15. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\color{blue}{\sqrt{k}} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}} \]
    16. pow-lowering-pow.f64N/A

      \[\leadsto \frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\sqrt{k} \cdot \color{blue}{{\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\left(\frac{k}{2}\right)}}} \]
  4. Applied egg-rr99.7%

    \[\leadsto \color{blue}{\frac{\sqrt{2 \cdot \left(\pi \cdot n\right)}}{\sqrt{k} \cdot {\left(2 \cdot \left(\pi \cdot n\right)\right)}^{\left(k \cdot 0.5\right)}}} \]
  5. Step-by-step derivation
    1. *-commutativeN/A

      \[\leadsto \frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\color{blue}{{\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)} \cdot \sqrt{k}}} \]
    2. associate-/r*N/A

      \[\leadsto \color{blue}{\frac{\frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{{\left(2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)\right)}^{\left(k \cdot \frac{1}{2}\right)}}}{\sqrt{k}}} \]
  6. Applied egg-rr99.6%

    \[\leadsto \color{blue}{\frac{{\left(\pi \cdot \left(2 \cdot n\right)\right)}^{\left(\mathsf{fma}\left(k, -0.5, 0.5\right)\right)}}{\sqrt{k}}} \]
  7. Add Preprocessing

Alternative 4: 61.6% accurate, 2.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;k \leq 0.5:\\ \;\;\;\;\sqrt{\frac{\pi}{k}} \cdot \sqrt{2 \cdot n}\\ \mathbf{else}:\\ \;\;\;\;\sqrt{\sqrt{\frac{1}{k} \cdot \frac{1}{k}}}\\ \end{array} \end{array} \]
(FPCore (k n)
 :precision binary64
 (if (<= k 0.5)
   (* (sqrt (/ PI k)) (sqrt (* 2.0 n)))
   (sqrt (sqrt (* (/ 1.0 k) (/ 1.0 k))))))
double code(double k, double n) {
	double tmp;
	if (k <= 0.5) {
		tmp = sqrt((((double) M_PI) / k)) * sqrt((2.0 * n));
	} else {
		tmp = sqrt(sqrt(((1.0 / k) * (1.0 / k))));
	}
	return tmp;
}
public static double code(double k, double n) {
	double tmp;
	if (k <= 0.5) {
		tmp = Math.sqrt((Math.PI / k)) * Math.sqrt((2.0 * n));
	} else {
		tmp = Math.sqrt(Math.sqrt(((1.0 / k) * (1.0 / k))));
	}
	return tmp;
}
def code(k, n):
	tmp = 0
	if k <= 0.5:
		tmp = math.sqrt((math.pi / k)) * math.sqrt((2.0 * n))
	else:
		tmp = math.sqrt(math.sqrt(((1.0 / k) * (1.0 / k))))
	return tmp
function code(k, n)
	tmp = 0.0
	if (k <= 0.5)
		tmp = Float64(sqrt(Float64(pi / k)) * sqrt(Float64(2.0 * n)));
	else
		tmp = sqrt(sqrt(Float64(Float64(1.0 / k) * Float64(1.0 / k))));
	end
	return tmp
end
function tmp_2 = code(k, n)
	tmp = 0.0;
	if (k <= 0.5)
		tmp = sqrt((pi / k)) * sqrt((2.0 * n));
	else
		tmp = sqrt(sqrt(((1.0 / k) * (1.0 / k))));
	end
	tmp_2 = tmp;
end
code[k_, n_] := If[LessEqual[k, 0.5], N[(N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(2.0 * n), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], N[Sqrt[N[Sqrt[N[(N[(1.0 / k), $MachinePrecision] * N[(1.0 / k), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]], $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;k \leq 0.5:\\
\;\;\;\;\sqrt{\frac{\pi}{k}} \cdot \sqrt{2 \cdot n}\\

\mathbf{else}:\\
\;\;\;\;\sqrt{\sqrt{\frac{1}{k} \cdot \frac{1}{k}}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if k < 0.5

    1. Initial program 99.2%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in k around 0

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
      2. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
      3. /-lowering-/.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \sqrt{\frac{\color{blue}{n \cdot \mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
      5. PI-lowering-PI.f64N/A

        \[\leadsto \sqrt{\frac{n \cdot \color{blue}{\mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
      6. sqrt-lowering-sqrt.f6475.3

        \[\leadsto \sqrt{\frac{n \cdot \pi}{k}} \cdot \color{blue}{\sqrt{2}} \]
    5. Simplified75.3%

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2}} \]
    6. Step-by-step derivation
      1. sqrt-unprodN/A

        \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k} \cdot 2}} \]
      2. associate-*l/N/A

        \[\leadsto \sqrt{\color{blue}{\frac{\left(n \cdot \mathsf{PI}\left(\right)\right) \cdot 2}{k}}} \]
      3. *-commutativeN/A

        \[\leadsto \sqrt{\frac{\color{blue}{2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)}}{k}} \]
      4. *-commutativeN/A

        \[\leadsto \sqrt{\frac{2 \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot n\right)}}{k}} \]
      5. sqrt-undivN/A

        \[\leadsto \color{blue}{\frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\sqrt{k}}} \]
      6. /-lowering-/.f64N/A

        \[\leadsto \color{blue}{\frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\sqrt{k}}} \]
      7. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \frac{\color{blue}{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k}} \]
      8. *-commutativeN/A

        \[\leadsto \frac{\sqrt{2 \cdot \color{blue}{\left(n \cdot \mathsf{PI}\left(\right)\right)}}}{\sqrt{k}} \]
      9. associate-*r*N/A

        \[\leadsto \frac{\sqrt{\color{blue}{\left(2 \cdot n\right) \cdot \mathsf{PI}\left(\right)}}}{\sqrt{k}} \]
      10. metadata-evalN/A

        \[\leadsto \frac{\sqrt{\left(\color{blue}{\frac{-2}{-1}} \cdot n\right) \cdot \mathsf{PI}\left(\right)}}{\sqrt{k}} \]
      11. associate-/r/N/A

        \[\leadsto \frac{\sqrt{\color{blue}{\frac{-2}{\frac{-1}{n}}} \cdot \mathsf{PI}\left(\right)}}{\sqrt{k}} \]
      12. *-commutativeN/A

        \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}}{\sqrt{k}} \]
      13. *-lowering-*.f64N/A

        \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}}{\sqrt{k}} \]
      14. PI-lowering-PI.f64N/A

        \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right)} \cdot \frac{-2}{\frac{-1}{n}}}}{\sqrt{k}} \]
      15. associate-/r/N/A

        \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(\frac{-2}{-1} \cdot n\right)}}}{\sqrt{k}} \]
      16. metadata-evalN/A

        \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(\color{blue}{2} \cdot n\right)}}{\sqrt{k}} \]
      17. *-lowering-*.f64N/A

        \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(2 \cdot n\right)}}}{\sqrt{k}} \]
      18. sqrt-lowering-sqrt.f6498.4

        \[\leadsto \frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\color{blue}{\sqrt{k}}} \]
    7. Applied egg-rr98.4%

      \[\leadsto \color{blue}{\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\sqrt{k}}} \]
    8. Step-by-step derivation
      1. sqrt-prodN/A

        \[\leadsto \frac{\color{blue}{\sqrt{\mathsf{PI}\left(\right)} \cdot \sqrt{2 \cdot n}}}{\sqrt{k}} \]
      2. pow1/2N/A

        \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right)} \cdot \color{blue}{{\left(2 \cdot n\right)}^{\frac{1}{2}}}}{\sqrt{k}} \]
      3. associate-*l/N/A

        \[\leadsto \color{blue}{\frac{\sqrt{\mathsf{PI}\left(\right)}}{\sqrt{k}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}}} \]
      4. sqrt-divN/A

        \[\leadsto \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k}}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
      5. *-lowering-*.f64N/A

        \[\leadsto \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}}} \]
      6. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k}}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
      7. /-lowering-/.f64N/A

        \[\leadsto \sqrt{\color{blue}{\frac{\mathsf{PI}\left(\right)}{k}}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
      8. PI-lowering-PI.f64N/A

        \[\leadsto \sqrt{\frac{\color{blue}{\mathsf{PI}\left(\right)}}{k}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
      9. pow1/2N/A

        \[\leadsto \sqrt{\frac{\mathsf{PI}\left(\right)}{k}} \cdot \color{blue}{\sqrt{2 \cdot n}} \]
      10. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \sqrt{\frac{\mathsf{PI}\left(\right)}{k}} \cdot \color{blue}{\sqrt{2 \cdot n}} \]
      11. *-lowering-*.f6498.5

        \[\leadsto \sqrt{\frac{\pi}{k}} \cdot \sqrt{\color{blue}{2 \cdot n}} \]
    9. Applied egg-rr98.5%

      \[\leadsto \color{blue}{\sqrt{\frac{\pi}{k}} \cdot \sqrt{2 \cdot n}} \]

    if 0.5 < k

    1. Initial program 100.0%

      \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. Add Preprocessing
    3. Taylor expanded in k around inf

      \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\color{blue}{\left(\frac{-1}{2} \cdot k\right)}} \]
    4. Step-by-step derivation
      1. *-lowering-*.f64100.0

        \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\left(-0.5 \cdot k\right)}} \]
    5. Simplified100.0%

      \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\left(-0.5 \cdot k\right)}} \]
    6. Taylor expanded in k around 0

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

        \[\leadsto \color{blue}{\sqrt{\frac{1}{k}}} \]
      2. /-lowering-/.f643.3

        \[\leadsto \sqrt{\color{blue}{\frac{1}{k}}} \]
    8. Simplified3.3%

      \[\leadsto \color{blue}{\sqrt{\frac{1}{k}}} \]
    9. Step-by-step derivation
      1. rem-square-sqrtN/A

        \[\leadsto \sqrt{\color{blue}{\sqrt{\frac{1}{k}} \cdot \sqrt{\frac{1}{k}}}} \]
      2. sqrt-unprodN/A

        \[\leadsto \sqrt{\color{blue}{\sqrt{\frac{1}{k} \cdot \frac{1}{k}}}} \]
      3. sqrt-lowering-sqrt.f64N/A

        \[\leadsto \sqrt{\color{blue}{\sqrt{\frac{1}{k} \cdot \frac{1}{k}}}} \]
      4. *-lowering-*.f64N/A

        \[\leadsto \sqrt{\sqrt{\color{blue}{\frac{1}{k} \cdot \frac{1}{k}}}} \]
      5. /-lowering-/.f64N/A

        \[\leadsto \sqrt{\sqrt{\color{blue}{\frac{1}{k}} \cdot \frac{1}{k}}} \]
      6. /-lowering-/.f6429.2

        \[\leadsto \sqrt{\sqrt{\frac{1}{k} \cdot \color{blue}{\frac{1}{k}}}} \]
    10. Applied egg-rr29.2%

      \[\leadsto \sqrt{\color{blue}{\sqrt{\frac{1}{k} \cdot \frac{1}{k}}}} \]
  3. Recombined 2 regimes into one program.
  4. Add Preprocessing

Alternative 5: 50.9% accurate, 3.6× speedup?

\[\begin{array}{l} \\ \sqrt{\frac{\pi}{k}} \cdot \sqrt{2 \cdot n} \end{array} \]
(FPCore (k n) :precision binary64 (* (sqrt (/ PI k)) (sqrt (* 2.0 n))))
double code(double k, double n) {
	return sqrt((((double) M_PI) / k)) * sqrt((2.0 * n));
}
public static double code(double k, double n) {
	return Math.sqrt((Math.PI / k)) * Math.sqrt((2.0 * n));
}
def code(k, n):
	return math.sqrt((math.pi / k)) * math.sqrt((2.0 * n))
function code(k, n)
	return Float64(sqrt(Float64(pi / k)) * sqrt(Float64(2.0 * n)))
end
function tmp = code(k, n)
	tmp = sqrt((pi / k)) * sqrt((2.0 * n));
end
code[k_, n_] := N[(N[Sqrt[N[(Pi / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[N[(2.0 * n), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\sqrt{\frac{\pi}{k}} \cdot \sqrt{2 \cdot n}
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Add Preprocessing
  3. Taylor expanded in k around 0

    \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
  4. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
    2. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \sqrt{\color{blue}{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \sqrt{\frac{\color{blue}{n \cdot \mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
    5. PI-lowering-PI.f64N/A

      \[\leadsto \sqrt{\frac{n \cdot \color{blue}{\mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
    6. sqrt-lowering-sqrt.f6439.8

      \[\leadsto \sqrt{\frac{n \cdot \pi}{k}} \cdot \color{blue}{\sqrt{2}} \]
  5. Simplified39.8%

    \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2}} \]
  6. Step-by-step derivation
    1. sqrt-unprodN/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k} \cdot 2}} \]
    2. associate-*l/N/A

      \[\leadsto \sqrt{\color{blue}{\frac{\left(n \cdot \mathsf{PI}\left(\right)\right) \cdot 2}{k}}} \]
    3. *-commutativeN/A

      \[\leadsto \sqrt{\frac{\color{blue}{2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)}}{k}} \]
    4. *-commutativeN/A

      \[\leadsto \sqrt{\frac{2 \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot n\right)}}{k}} \]
    5. sqrt-undivN/A

      \[\leadsto \color{blue}{\frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\sqrt{k}}} \]
    6. /-lowering-/.f64N/A

      \[\leadsto \color{blue}{\frac{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}{\sqrt{k}}} \]
    7. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \frac{\color{blue}{\sqrt{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}}}{\sqrt{k}} \]
    8. *-commutativeN/A

      \[\leadsto \frac{\sqrt{2 \cdot \color{blue}{\left(n \cdot \mathsf{PI}\left(\right)\right)}}}{\sqrt{k}} \]
    9. associate-*r*N/A

      \[\leadsto \frac{\sqrt{\color{blue}{\left(2 \cdot n\right) \cdot \mathsf{PI}\left(\right)}}}{\sqrt{k}} \]
    10. metadata-evalN/A

      \[\leadsto \frac{\sqrt{\left(\color{blue}{\frac{-2}{-1}} \cdot n\right) \cdot \mathsf{PI}\left(\right)}}{\sqrt{k}} \]
    11. associate-/r/N/A

      \[\leadsto \frac{\sqrt{\color{blue}{\frac{-2}{\frac{-1}{n}}} \cdot \mathsf{PI}\left(\right)}}{\sqrt{k}} \]
    12. *-commutativeN/A

      \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}}{\sqrt{k}} \]
    13. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}}{\sqrt{k}} \]
    14. PI-lowering-PI.f64N/A

      \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{PI}\left(\right)} \cdot \frac{-2}{\frac{-1}{n}}}}{\sqrt{k}} \]
    15. associate-/r/N/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(\frac{-2}{-1} \cdot n\right)}}}{\sqrt{k}} \]
    16. metadata-evalN/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \left(\color{blue}{2} \cdot n\right)}}{\sqrt{k}} \]
    17. *-lowering-*.f64N/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(2 \cdot n\right)}}}{\sqrt{k}} \]
    18. sqrt-lowering-sqrt.f6451.7

      \[\leadsto \frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\color{blue}{\sqrt{k}}} \]
  7. Applied egg-rr51.7%

    \[\leadsto \color{blue}{\frac{\sqrt{\pi \cdot \left(2 \cdot n\right)}}{\sqrt{k}}} \]
  8. Step-by-step derivation
    1. sqrt-prodN/A

      \[\leadsto \frac{\color{blue}{\sqrt{\mathsf{PI}\left(\right)} \cdot \sqrt{2 \cdot n}}}{\sqrt{k}} \]
    2. pow1/2N/A

      \[\leadsto \frac{\sqrt{\mathsf{PI}\left(\right)} \cdot \color{blue}{{\left(2 \cdot n\right)}^{\frac{1}{2}}}}{\sqrt{k}} \]
    3. associate-*l/N/A

      \[\leadsto \color{blue}{\frac{\sqrt{\mathsf{PI}\left(\right)}}{\sqrt{k}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}}} \]
    4. sqrt-divN/A

      \[\leadsto \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k}}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
    5. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}}} \]
    6. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k}}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
    7. /-lowering-/.f64N/A

      \[\leadsto \sqrt{\color{blue}{\frac{\mathsf{PI}\left(\right)}{k}}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
    8. PI-lowering-PI.f64N/A

      \[\leadsto \sqrt{\frac{\color{blue}{\mathsf{PI}\left(\right)}}{k}} \cdot {\left(2 \cdot n\right)}^{\frac{1}{2}} \]
    9. pow1/2N/A

      \[\leadsto \sqrt{\frac{\mathsf{PI}\left(\right)}{k}} \cdot \color{blue}{\sqrt{2 \cdot n}} \]
    10. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \sqrt{\frac{\mathsf{PI}\left(\right)}{k}} \cdot \color{blue}{\sqrt{2 \cdot n}} \]
    11. *-lowering-*.f6451.8

      \[\leadsto \sqrt{\frac{\pi}{k}} \cdot \sqrt{\color{blue}{2 \cdot n}} \]
  9. Applied egg-rr51.8%

    \[\leadsto \color{blue}{\sqrt{\frac{\pi}{k}} \cdot \sqrt{2 \cdot n}} \]
  10. Add Preprocessing

Alternative 6: 50.9% accurate, 3.6× speedup?

\[\begin{array}{l} \\ \sqrt{n} \cdot \sqrt{2 \cdot \frac{\pi}{k}} \end{array} \]
(FPCore (k n) :precision binary64 (* (sqrt n) (sqrt (* 2.0 (/ PI k)))))
double code(double k, double n) {
	return sqrt(n) * sqrt((2.0 * (((double) M_PI) / k)));
}
public static double code(double k, double n) {
	return Math.sqrt(n) * Math.sqrt((2.0 * (Math.PI / k)));
}
def code(k, n):
	return math.sqrt(n) * math.sqrt((2.0 * (math.pi / k)))
function code(k, n)
	return Float64(sqrt(n) * sqrt(Float64(2.0 * Float64(pi / k))))
end
function tmp = code(k, n)
	tmp = sqrt(n) * sqrt((2.0 * (pi / k)));
end
code[k_, n_] := N[(N[Sqrt[n], $MachinePrecision] * N[Sqrt[N[(2.0 * N[(Pi / k), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\sqrt{n} \cdot \sqrt{2 \cdot \frac{\pi}{k}}
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Add Preprocessing
  3. Taylor expanded in k around 0

    \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
  4. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
    2. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \sqrt{\color{blue}{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \sqrt{\frac{\color{blue}{n \cdot \mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
    5. PI-lowering-PI.f64N/A

      \[\leadsto \sqrt{\frac{n \cdot \color{blue}{\mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
    6. sqrt-lowering-sqrt.f6439.8

      \[\leadsto \sqrt{\frac{n \cdot \pi}{k}} \cdot \color{blue}{\sqrt{2}} \]
  5. Simplified39.8%

    \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2}} \]
  6. Step-by-step derivation
    1. sqrt-unprodN/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k} \cdot 2}} \]
    2. associate-/l*N/A

      \[\leadsto \sqrt{\color{blue}{\left(n \cdot \frac{\mathsf{PI}\left(\right)}{k}\right)} \cdot 2} \]
    3. associate-*l*N/A

      \[\leadsto \sqrt{\color{blue}{n \cdot \left(\frac{\mathsf{PI}\left(\right)}{k} \cdot 2\right)}} \]
    4. sqrt-prodN/A

      \[\leadsto \color{blue}{\sqrt{n} \cdot \sqrt{\frac{\mathsf{PI}\left(\right)}{k} \cdot 2}} \]
    5. pow1/2N/A

      \[\leadsto \color{blue}{{n}^{\frac{1}{2}}} \cdot \sqrt{\frac{\mathsf{PI}\left(\right)}{k} \cdot 2} \]
    6. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{{n}^{\frac{1}{2}} \cdot \sqrt{\frac{\mathsf{PI}\left(\right)}{k} \cdot 2}} \]
    7. pow1/2N/A

      \[\leadsto \color{blue}{\sqrt{n}} \cdot \sqrt{\frac{\mathsf{PI}\left(\right)}{k} \cdot 2} \]
    8. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \color{blue}{\sqrt{n}} \cdot \sqrt{\frac{\mathsf{PI}\left(\right)}{k} \cdot 2} \]
    9. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \sqrt{n} \cdot \color{blue}{\sqrt{\frac{\mathsf{PI}\left(\right)}{k} \cdot 2}} \]
    10. *-lowering-*.f64N/A

      \[\leadsto \sqrt{n} \cdot \sqrt{\color{blue}{\frac{\mathsf{PI}\left(\right)}{k} \cdot 2}} \]
    11. /-lowering-/.f64N/A

      \[\leadsto \sqrt{n} \cdot \sqrt{\color{blue}{\frac{\mathsf{PI}\left(\right)}{k}} \cdot 2} \]
    12. PI-lowering-PI.f6451.8

      \[\leadsto \sqrt{n} \cdot \sqrt{\frac{\color{blue}{\pi}}{k} \cdot 2} \]
  7. Applied egg-rr51.8%

    \[\leadsto \color{blue}{\sqrt{n} \cdot \sqrt{\frac{\pi}{k} \cdot 2}} \]
  8. Final simplification51.8%

    \[\leadsto \sqrt{n} \cdot \sqrt{2 \cdot \frac{\pi}{k}} \]
  9. Add Preprocessing

Alternative 7: 39.3% accurate, 4.8× speedup?

\[\begin{array}{l} \\ \sqrt{\frac{\pi \cdot \left(2 \cdot n\right)}{k}} \end{array} \]
(FPCore (k n) :precision binary64 (sqrt (/ (* PI (* 2.0 n)) k)))
double code(double k, double n) {
	return sqrt(((((double) M_PI) * (2.0 * n)) / k));
}
public static double code(double k, double n) {
	return Math.sqrt(((Math.PI * (2.0 * n)) / k));
}
def code(k, n):
	return math.sqrt(((math.pi * (2.0 * n)) / k))
function code(k, n)
	return sqrt(Float64(Float64(pi * Float64(2.0 * n)) / k))
end
function tmp = code(k, n)
	tmp = sqrt(((pi * (2.0 * n)) / k));
end
code[k_, n_] := N[Sqrt[N[(N[(Pi * N[(2.0 * n), $MachinePrecision]), $MachinePrecision] / k), $MachinePrecision]], $MachinePrecision]
\begin{array}{l}

\\
\sqrt{\frac{\pi \cdot \left(2 \cdot n\right)}{k}}
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Add Preprocessing
  3. Taylor expanded in k around 0

    \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
  4. Step-by-step derivation
    1. *-lowering-*.f64N/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}} \cdot \sqrt{2}} \]
    2. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
    3. /-lowering-/.f64N/A

      \[\leadsto \sqrt{\color{blue}{\frac{n \cdot \mathsf{PI}\left(\right)}{k}}} \cdot \sqrt{2} \]
    4. *-lowering-*.f64N/A

      \[\leadsto \sqrt{\frac{\color{blue}{n \cdot \mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
    5. PI-lowering-PI.f64N/A

      \[\leadsto \sqrt{\frac{n \cdot \color{blue}{\mathsf{PI}\left(\right)}}{k}} \cdot \sqrt{2} \]
    6. sqrt-lowering-sqrt.f6439.8

      \[\leadsto \sqrt{\frac{n \cdot \pi}{k}} \cdot \color{blue}{\sqrt{2}} \]
  5. Simplified39.8%

    \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2}} \]
  6. Step-by-step derivation
    1. sqrt-unprodN/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k} \cdot 2}} \]
    2. sqrt-lowering-sqrt.f64N/A

      \[\leadsto \color{blue}{\sqrt{\frac{n \cdot \mathsf{PI}\left(\right)}{k} \cdot 2}} \]
    3. associate-*l/N/A

      \[\leadsto \sqrt{\color{blue}{\frac{\left(n \cdot \mathsf{PI}\left(\right)\right) \cdot 2}{k}}} \]
    4. *-commutativeN/A

      \[\leadsto \sqrt{\frac{\color{blue}{2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)}}{k}} \]
    5. *-commutativeN/A

      \[\leadsto \sqrt{\frac{2 \cdot \color{blue}{\left(\mathsf{PI}\left(\right) \cdot n\right)}}{k}} \]
    6. /-lowering-/.f64N/A

      \[\leadsto \sqrt{\color{blue}{\frac{2 \cdot \left(\mathsf{PI}\left(\right) \cdot n\right)}{k}}} \]
    7. *-commutativeN/A

      \[\leadsto \sqrt{\frac{2 \cdot \color{blue}{\left(n \cdot \mathsf{PI}\left(\right)\right)}}{k}} \]
    8. associate-*r*N/A

      \[\leadsto \sqrt{\frac{\color{blue}{\left(2 \cdot n\right) \cdot \mathsf{PI}\left(\right)}}{k}} \]
    9. metadata-evalN/A

      \[\leadsto \sqrt{\frac{\left(\color{blue}{\frac{-2}{-1}} \cdot n\right) \cdot \mathsf{PI}\left(\right)}{k}} \]
    10. associate-/r/N/A

      \[\leadsto \sqrt{\frac{\color{blue}{\frac{-2}{\frac{-1}{n}}} \cdot \mathsf{PI}\left(\right)}{k}} \]
    11. *-commutativeN/A

      \[\leadsto \sqrt{\frac{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}{k}} \]
    12. *-lowering-*.f64N/A

      \[\leadsto \sqrt{\frac{\color{blue}{\mathsf{PI}\left(\right) \cdot \frac{-2}{\frac{-1}{n}}}}{k}} \]
    13. PI-lowering-PI.f64N/A

      \[\leadsto \sqrt{\frac{\color{blue}{\mathsf{PI}\left(\right)} \cdot \frac{-2}{\frac{-1}{n}}}{k}} \]
    14. associate-/r/N/A

      \[\leadsto \sqrt{\frac{\mathsf{PI}\left(\right) \cdot \color{blue}{\left(\frac{-2}{-1} \cdot n\right)}}{k}} \]
    15. metadata-evalN/A

      \[\leadsto \sqrt{\frac{\mathsf{PI}\left(\right) \cdot \left(\color{blue}{2} \cdot n\right)}{k}} \]
    16. *-lowering-*.f6439.9

      \[\leadsto \sqrt{\frac{\pi \cdot \color{blue}{\left(2 \cdot n\right)}}{k}} \]
  7. Applied egg-rr39.9%

    \[\leadsto \color{blue}{\sqrt{\frac{\pi \cdot \left(2 \cdot n\right)}{k}}} \]
  8. Add Preprocessing

Alternative 8: 5.1% accurate, 6.9× speedup?

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

\\
\sqrt{\frac{1}{k}}
\end{array}
Derivation
  1. Initial program 99.6%

    \[\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  2. Add Preprocessing
  3. Taylor expanded in k around inf

    \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \mathsf{PI}\left(\right)\right) \cdot n\right)}^{\color{blue}{\left(\frac{-1}{2} \cdot k\right)}} \]
  4. Step-by-step derivation
    1. *-lowering-*.f6452.6

      \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\left(-0.5 \cdot k\right)}} \]
  5. Simplified52.6%

    \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\left(-0.5 \cdot k\right)}} \]
  6. Taylor expanded in k around 0

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

      \[\leadsto \color{blue}{\sqrt{\frac{1}{k}}} \]
    2. /-lowering-/.f645.4

      \[\leadsto \sqrt{\color{blue}{\frac{1}{k}}} \]
  8. Simplified5.4%

    \[\leadsto \color{blue}{\sqrt{\frac{1}{k}}} \]
  9. Add Preprocessing

Reproduce

?
herbie shell --seed 2024201 
(FPCore (k n)
  :name "Migdal et al, Equation (51)"
  :precision binary64
  (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))))