Migdal et al, Equation (51)

Percentage Accurate: 99.4% → 99.4%
Time: 4.6s
Alternatives: 7
Speedup: 1.0×

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}

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 7 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: 99.4% accurate, 1.0× speedup?

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

\\
\sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(0.5 + -0.5 \cdot k\right)}
\end{array}
Derivation
  1. Initial program 99.4%

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

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

      \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
    2. lower-/.f6499.4

      \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
  4. Applied rewrites99.4%

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

    \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{\color{blue}{1}}{2}\right)} \]
  6. Step-by-step derivation
    1. Applied rewrites49.5%

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

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

        \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1}{2} + \color{blue}{\frac{-1}{2} \cdot k}\right)} \]
      2. lower-*.f6499.4

        \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(0.5 + -0.5 \cdot \color{blue}{k}\right)} \]
    4. Applied rewrites99.4%

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

    Alternative 2: 98.1% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \left(2 \cdot \pi\right) \cdot n\\ \mathbf{if}\;k \leq 1:\\ \;\;\;\;\sqrt{\frac{1}{k}} \cdot {t\_0}^{0.5}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\sqrt{k}} \cdot {t\_0}^{\left(-0.5 \cdot k\right)}\\ \end{array} \end{array} \]
    (FPCore (k n)
     :precision binary64
     (let* ((t_0 (* (* 2.0 PI) n)))
       (if (<= k 1.0)
         (* (sqrt (/ 1.0 k)) (pow t_0 0.5))
         (* (/ 1.0 (sqrt k)) (pow t_0 (* -0.5 k))))))
    double code(double k, double n) {
    	double t_0 = (2.0 * ((double) M_PI)) * n;
    	double tmp;
    	if (k <= 1.0) {
    		tmp = sqrt((1.0 / k)) * pow(t_0, 0.5);
    	} else {
    		tmp = (1.0 / sqrt(k)) * pow(t_0, (-0.5 * k));
    	}
    	return tmp;
    }
    
    public static double code(double k, double n) {
    	double t_0 = (2.0 * Math.PI) * n;
    	double tmp;
    	if (k <= 1.0) {
    		tmp = Math.sqrt((1.0 / k)) * Math.pow(t_0, 0.5);
    	} else {
    		tmp = (1.0 / Math.sqrt(k)) * Math.pow(t_0, (-0.5 * k));
    	}
    	return tmp;
    }
    
    def code(k, n):
    	t_0 = (2.0 * math.pi) * n
    	tmp = 0
    	if k <= 1.0:
    		tmp = math.sqrt((1.0 / k)) * math.pow(t_0, 0.5)
    	else:
    		tmp = (1.0 / math.sqrt(k)) * math.pow(t_0, (-0.5 * k))
    	return tmp
    
    function code(k, n)
    	t_0 = Float64(Float64(2.0 * pi) * n)
    	tmp = 0.0
    	if (k <= 1.0)
    		tmp = Float64(sqrt(Float64(1.0 / k)) * (t_0 ^ 0.5));
    	else
    		tmp = Float64(Float64(1.0 / sqrt(k)) * (t_0 ^ Float64(-0.5 * k)));
    	end
    	return tmp
    end
    
    function tmp_2 = code(k, n)
    	t_0 = (2.0 * pi) * n;
    	tmp = 0.0;
    	if (k <= 1.0)
    		tmp = sqrt((1.0 / k)) * (t_0 ^ 0.5);
    	else
    		tmp = (1.0 / sqrt(k)) * (t_0 ^ (-0.5 * k));
    	end
    	tmp_2 = tmp;
    end
    
    code[k_, n_] := Block[{t$95$0 = N[(N[(2.0 * Pi), $MachinePrecision] * n), $MachinePrecision]}, If[LessEqual[k, 1.0], N[(N[Sqrt[N[(1.0 / k), $MachinePrecision]], $MachinePrecision] * N[Power[t$95$0, 0.5], $MachinePrecision]), $MachinePrecision], N[(N[(1.0 / N[Sqrt[k], $MachinePrecision]), $MachinePrecision] * N[Power[t$95$0, N[(-0.5 * k), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := \left(2 \cdot \pi\right) \cdot n\\
    \mathbf{if}\;k \leq 1:\\
    \;\;\;\;\sqrt{\frac{1}{k}} \cdot {t\_0}^{0.5}\\
    
    \mathbf{else}:\\
    \;\;\;\;\frac{1}{\sqrt{k}} \cdot {t\_0}^{\left(-0.5 \cdot k\right)}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if k < 1

      1. Initial program 98.8%

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

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

          \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
        2. lower-/.f6498.9

          \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
      4. Applied rewrites98.9%

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

        \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{\color{blue}{1}}{2}\right)} \]
      6. Step-by-step derivation
        1. Applied rewrites96.5%

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

          \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\frac{1}{2}}} \]
        3. Step-by-step derivation
          1. Applied rewrites96.5%

            \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{0.5}} \]

          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. Taylor expanded in k around inf

            \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\left(\frac{-1}{2} \cdot k\right)}} \]
          3. Step-by-step derivation
            1. lower-*.f6499.7

              \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(-0.5 \cdot \color{blue}{k}\right)} \]
          4. Applied rewrites99.7%

            \[\leadsto \frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\left(-0.5 \cdot k\right)}} \]
        4. Recombined 2 regimes into one program.
        5. Add Preprocessing

        Alternative 3: 62.4% accurate, 1.1× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;k \leq 1.85 \cdot 10^{-44}:\\ \;\;\;\;\sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{0.5}\\ \mathbf{else}:\\ \;\;\;\;\frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k}\\ \end{array} \end{array} \]
        (FPCore (k n)
         :precision binary64
         (if (<= k 1.85e-44)
           (* (sqrt (/ 1.0 k)) (pow (* (* 2.0 PI) n) 0.5))
           (/ (* n (* (sqrt (/ (* k PI) n)) (sqrt 2.0))) k)))
        double code(double k, double n) {
        	double tmp;
        	if (k <= 1.85e-44) {
        		tmp = sqrt((1.0 / k)) * pow(((2.0 * ((double) M_PI)) * n), 0.5);
        	} else {
        		tmp = (n * (sqrt(((k * ((double) M_PI)) / n)) * sqrt(2.0))) / k;
        	}
        	return tmp;
        }
        
        public static double code(double k, double n) {
        	double tmp;
        	if (k <= 1.85e-44) {
        		tmp = Math.sqrt((1.0 / k)) * Math.pow(((2.0 * Math.PI) * n), 0.5);
        	} else {
        		tmp = (n * (Math.sqrt(((k * Math.PI) / n)) * Math.sqrt(2.0))) / k;
        	}
        	return tmp;
        }
        
        def code(k, n):
        	tmp = 0
        	if k <= 1.85e-44:
        		tmp = math.sqrt((1.0 / k)) * math.pow(((2.0 * math.pi) * n), 0.5)
        	else:
        		tmp = (n * (math.sqrt(((k * math.pi) / n)) * math.sqrt(2.0))) / k
        	return tmp
        
        function code(k, n)
        	tmp = 0.0
        	if (k <= 1.85e-44)
        		tmp = Float64(sqrt(Float64(1.0 / k)) * (Float64(Float64(2.0 * pi) * n) ^ 0.5));
        	else
        		tmp = Float64(Float64(n * Float64(sqrt(Float64(Float64(k * pi) / n)) * sqrt(2.0))) / k);
        	end
        	return tmp
        end
        
        function tmp_2 = code(k, n)
        	tmp = 0.0;
        	if (k <= 1.85e-44)
        		tmp = sqrt((1.0 / k)) * (((2.0 * pi) * n) ^ 0.5);
        	else
        		tmp = (n * (sqrt(((k * pi) / n)) * sqrt(2.0))) / k;
        	end
        	tmp_2 = tmp;
        end
        
        code[k_, n_] := If[LessEqual[k, 1.85e-44], N[(N[Sqrt[N[(1.0 / k), $MachinePrecision]], $MachinePrecision] * N[Power[N[(N[(2.0 * Pi), $MachinePrecision] * n), $MachinePrecision], 0.5], $MachinePrecision]), $MachinePrecision], N[(N[(n * N[(N[Sqrt[N[(N[(k * Pi), $MachinePrecision] / n), $MachinePrecision]], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / k), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;k \leq 1.85 \cdot 10^{-44}:\\
        \;\;\;\;\sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{0.5}\\
        
        \mathbf{else}:\\
        \;\;\;\;\frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if k < 1.85e-44

          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. Taylor expanded in k around 0

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

              \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
            2. lower-/.f6499.2

              \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
          4. Applied rewrites99.2%

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

            \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{\color{blue}{1}}{2}\right)} \]
          6. Step-by-step derivation
            1. Applied rewrites99.2%

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

              \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{\frac{1}{2}}} \]
            3. Step-by-step derivation
              1. Applied rewrites99.2%

                \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\color{blue}{0.5}} \]

              if 1.85e-44 < k

              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. Taylor expanded in k around 0

                \[\leadsto \color{blue}{\frac{k \cdot \left(\frac{-1}{2} \cdot \left(\sqrt{k \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(\log \left(2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sqrt{2}\right)\right) + k \cdot \left(\frac{-1}{48} \cdot \left(\sqrt{{k}^{3} \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)\right)}^{3} \cdot \sqrt{2}\right)\right) + \frac{1}{8} \cdot \left(\sqrt{k \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)\right)}^{2} \cdot \sqrt{2}\right)\right)\right)\right) + \sqrt{k \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2}}{k}} \]
              3. Applied rewrites43.2%

                \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(k, \mathsf{fma}\left(-0.5, \sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \left(\log \left(2 \cdot \left(n \cdot \pi\right)\right) \cdot \sqrt{2}\right), k \cdot \mathsf{fma}\left(-0.020833333333333332, \sqrt{{k}^{3} \cdot \left(n \cdot \pi\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \pi\right)\right)}^{3} \cdot \sqrt{2}\right), 0.125 \cdot \left(\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \pi\right)\right)}^{2} \cdot \sqrt{2}\right)\right)\right)\right), \sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}\right)}{k}} \]
              4. Taylor expanded in n around inf

                \[\leadsto \frac{n \cdot \left(k \cdot \left(\frac{-1}{2} \cdot \left(\sqrt{\frac{k \cdot \mathsf{PI}\left(\right)}{n}} \cdot \left(\sqrt{2} \cdot \left(\log \left(2 \cdot \mathsf{PI}\left(\right)\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)\right)\right) + k \cdot \left(\frac{-1}{48} \cdot \left(\sqrt{\frac{{k}^{3} \cdot \mathsf{PI}\left(\right)}{n}} \cdot \left(\sqrt{2} \cdot {\left(\log \left(2 \cdot \mathsf{PI}\left(\right)\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)}^{3}\right)\right) + \frac{1}{8} \cdot \left(\sqrt{\frac{k \cdot \mathsf{PI}\left(\right)}{n}} \cdot \left(\sqrt{2} \cdot {\left(\log \left(2 \cdot \mathsf{PI}\left(\right)\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)}^{2}\right)\right)\right)\right) + \sqrt{\frac{k \cdot \mathsf{PI}\left(\right)}{n}} \cdot \sqrt{2}\right)}{k} \]
              5. Applied rewrites50.6%

                \[\leadsto \frac{n \cdot \mathsf{fma}\left(k, \mathsf{fma}\left(-0.5, \sqrt{\frac{k \cdot \pi}{n}} \cdot \left(\sqrt{2} \cdot \left(\log \left(2 \cdot \pi\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)\right), k \cdot \mathsf{fma}\left(-0.020833333333333332, \sqrt{\frac{{k}^{3} \cdot \pi}{n}} \cdot \left(\sqrt{2} \cdot {\left(\log \left(2 \cdot \pi\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)}^{3}\right), 0.125 \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \left(\sqrt{2} \cdot {\left(\log \left(2 \cdot \pi\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)}^{2}\right)\right)\right)\right), \sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
              6. Taylor expanded in k around 0

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

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

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
                3. lift-/.f64N/A

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
                4. lift-sqrt.f64N/A

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
                5. lift-sqrt.f64N/A

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
                6. lift-*.f6434.9

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
              8. Applied rewrites34.9%

                \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
            4. Recombined 2 regimes into one program.
            5. Add Preprocessing

            Alternative 4: 62.4% accurate, 1.5× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;k \leq 1.75 \cdot 10^{-44}:\\ \;\;\;\;\sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k}\\ \end{array} \end{array} \]
            (FPCore (k n)
             :precision binary64
             (if (<= k 1.75e-44)
               (* (sqrt (/ 1.0 k)) (* (sqrt (* n PI)) (sqrt 2.0)))
               (/ (* n (* (sqrt (/ (* k PI) n)) (sqrt 2.0))) k)))
            double code(double k, double n) {
            	double tmp;
            	if (k <= 1.75e-44) {
            		tmp = sqrt((1.0 / k)) * (sqrt((n * ((double) M_PI))) * sqrt(2.0));
            	} else {
            		tmp = (n * (sqrt(((k * ((double) M_PI)) / n)) * sqrt(2.0))) / k;
            	}
            	return tmp;
            }
            
            public static double code(double k, double n) {
            	double tmp;
            	if (k <= 1.75e-44) {
            		tmp = Math.sqrt((1.0 / k)) * (Math.sqrt((n * Math.PI)) * Math.sqrt(2.0));
            	} else {
            		tmp = (n * (Math.sqrt(((k * Math.PI) / n)) * Math.sqrt(2.0))) / k;
            	}
            	return tmp;
            }
            
            def code(k, n):
            	tmp = 0
            	if k <= 1.75e-44:
            		tmp = math.sqrt((1.0 / k)) * (math.sqrt((n * math.pi)) * math.sqrt(2.0))
            	else:
            		tmp = (n * (math.sqrt(((k * math.pi) / n)) * math.sqrt(2.0))) / k
            	return tmp
            
            function code(k, n)
            	tmp = 0.0
            	if (k <= 1.75e-44)
            		tmp = Float64(sqrt(Float64(1.0 / k)) * Float64(sqrt(Float64(n * pi)) * sqrt(2.0)));
            	else
            		tmp = Float64(Float64(n * Float64(sqrt(Float64(Float64(k * pi) / n)) * sqrt(2.0))) / k);
            	end
            	return tmp
            end
            
            function tmp_2 = code(k, n)
            	tmp = 0.0;
            	if (k <= 1.75e-44)
            		tmp = sqrt((1.0 / k)) * (sqrt((n * pi)) * sqrt(2.0));
            	else
            		tmp = (n * (sqrt(((k * pi) / n)) * sqrt(2.0))) / k;
            	end
            	tmp_2 = tmp;
            end
            
            code[k_, n_] := If[LessEqual[k, 1.75e-44], N[(N[Sqrt[N[(1.0 / k), $MachinePrecision]], $MachinePrecision] * N[(N[Sqrt[N[(n * Pi), $MachinePrecision]], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(n * N[(N[Sqrt[N[(N[(k * Pi), $MachinePrecision] / n), $MachinePrecision]], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / k), $MachinePrecision]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;k \leq 1.75 \cdot 10^{-44}:\\
            \;\;\;\;\sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right)\\
            
            \mathbf{else}:\\
            \;\;\;\;\frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k}\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if k < 1.7499999999999999e-44

              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. Taylor expanded in k around 0

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

                  \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
                2. lower-/.f6499.2

                  \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
              4. Applied rewrites99.2%

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

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

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

                  \[\leadsto \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right) \]
                3. lift-sqrt.f64N/A

                  \[\leadsto \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{\color{blue}{2}}\right) \]
                4. lift-sqrt.f64N/A

                  \[\leadsto \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right) \]
                5. lift-*.f6499.1

                  \[\leadsto \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \color{blue}{\sqrt{2}}\right) \]
              7. Applied rewrites99.1%

                \[\leadsto \sqrt{\frac{1}{k}} \cdot \color{blue}{\left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right)} \]

              if 1.7499999999999999e-44 < k

              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. Taylor expanded in k around 0

                \[\leadsto \color{blue}{\frac{k \cdot \left(\frac{-1}{2} \cdot \left(\sqrt{k \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(\log \left(2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sqrt{2}\right)\right) + k \cdot \left(\frac{-1}{48} \cdot \left(\sqrt{{k}^{3} \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)\right)}^{3} \cdot \sqrt{2}\right)\right) + \frac{1}{8} \cdot \left(\sqrt{k \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)\right)}^{2} \cdot \sqrt{2}\right)\right)\right)\right) + \sqrt{k \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2}}{k}} \]
              3. Applied rewrites43.2%

                \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(k, \mathsf{fma}\left(-0.5, \sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \left(\log \left(2 \cdot \left(n \cdot \pi\right)\right) \cdot \sqrt{2}\right), k \cdot \mathsf{fma}\left(-0.020833333333333332, \sqrt{{k}^{3} \cdot \left(n \cdot \pi\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \pi\right)\right)}^{3} \cdot \sqrt{2}\right), 0.125 \cdot \left(\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \pi\right)\right)}^{2} \cdot \sqrt{2}\right)\right)\right)\right), \sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}\right)}{k}} \]
              4. Taylor expanded in n around inf

                \[\leadsto \frac{n \cdot \left(k \cdot \left(\frac{-1}{2} \cdot \left(\sqrt{\frac{k \cdot \mathsf{PI}\left(\right)}{n}} \cdot \left(\sqrt{2} \cdot \left(\log \left(2 \cdot \mathsf{PI}\left(\right)\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)\right)\right) + k \cdot \left(\frac{-1}{48} \cdot \left(\sqrt{\frac{{k}^{3} \cdot \mathsf{PI}\left(\right)}{n}} \cdot \left(\sqrt{2} \cdot {\left(\log \left(2 \cdot \mathsf{PI}\left(\right)\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)}^{3}\right)\right) + \frac{1}{8} \cdot \left(\sqrt{\frac{k \cdot \mathsf{PI}\left(\right)}{n}} \cdot \left(\sqrt{2} \cdot {\left(\log \left(2 \cdot \mathsf{PI}\left(\right)\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)}^{2}\right)\right)\right)\right) + \sqrt{\frac{k \cdot \mathsf{PI}\left(\right)}{n}} \cdot \sqrt{2}\right)}{k} \]
              5. Applied rewrites50.6%

                \[\leadsto \frac{n \cdot \mathsf{fma}\left(k, \mathsf{fma}\left(-0.5, \sqrt{\frac{k \cdot \pi}{n}} \cdot \left(\sqrt{2} \cdot \left(\log \left(2 \cdot \pi\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)\right), k \cdot \mathsf{fma}\left(-0.020833333333333332, \sqrt{\frac{{k}^{3} \cdot \pi}{n}} \cdot \left(\sqrt{2} \cdot {\left(\log \left(2 \cdot \pi\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)}^{3}\right), 0.125 \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \left(\sqrt{2} \cdot {\left(\log \left(2 \cdot \pi\right) + -1 \cdot \log \left(\frac{1}{n}\right)\right)}^{2}\right)\right)\right)\right), \sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
              6. Taylor expanded in k around 0

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

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

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
                3. lift-/.f64N/A

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
                4. lift-sqrt.f64N/A

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
                5. lift-sqrt.f64N/A

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
                6. lift-*.f6434.9

                  \[\leadsto \frac{n \cdot \left(\sqrt{\frac{k \cdot \pi}{n}} \cdot \sqrt{2}\right)}{k} \]
              8. Applied rewrites34.9%

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

            Alternative 5: 49.4% accurate, 2.0× speedup?

            \[\begin{array}{l} \\ \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right) \end{array} \]
            (FPCore (k n)
             :precision binary64
             (* (sqrt (/ 1.0 k)) (* (sqrt (* n PI)) (sqrt 2.0))))
            double code(double k, double n) {
            	return sqrt((1.0 / k)) * (sqrt((n * ((double) M_PI))) * sqrt(2.0));
            }
            
            public static double code(double k, double n) {
            	return Math.sqrt((1.0 / k)) * (Math.sqrt((n * Math.PI)) * Math.sqrt(2.0));
            }
            
            def code(k, n):
            	return math.sqrt((1.0 / k)) * (math.sqrt((n * math.pi)) * math.sqrt(2.0))
            
            function code(k, n)
            	return Float64(sqrt(Float64(1.0 / k)) * Float64(sqrt(Float64(n * pi)) * sqrt(2.0)))
            end
            
            function tmp = code(k, n)
            	tmp = sqrt((1.0 / k)) * (sqrt((n * pi)) * sqrt(2.0));
            end
            
            code[k_, n_] := N[(N[Sqrt[N[(1.0 / k), $MachinePrecision]], $MachinePrecision] * N[(N[Sqrt[N[(n * Pi), $MachinePrecision]], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right)
            \end{array}
            
            Derivation
            1. Initial program 99.4%

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

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

                \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
              2. lower-/.f6499.4

                \[\leadsto \sqrt{\frac{1}{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \]
            4. Applied rewrites99.4%

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

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

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

                \[\leadsto \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right) \]
              3. lift-sqrt.f64N/A

                \[\leadsto \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{\color{blue}{2}}\right) \]
              4. lift-sqrt.f64N/A

                \[\leadsto \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right) \]
              5. lift-*.f6449.4

                \[\leadsto \sqrt{\frac{1}{k}} \cdot \left(\sqrt{n \cdot \pi} \cdot \color{blue}{\sqrt{2}}\right) \]
            7. Applied rewrites49.4%

              \[\leadsto \sqrt{\frac{1}{k}} \cdot \color{blue}{\left(\sqrt{n \cdot \pi} \cdot \sqrt{2}\right)} \]
            8. Add Preprocessing

            Alternative 6: 49.3% accurate, 0.7× speedup?

            \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \leq 2 \cdot 10^{+126}:\\ \;\;\;\;\sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2}\\ \mathbf{else}:\\ \;\;\;\;\frac{\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}}{k}\\ \end{array} \end{array} \]
            (FPCore (k n)
             :precision binary64
             (if (<= (* (/ 1.0 (sqrt k)) (pow (* (* 2.0 PI) n) (/ (- 1.0 k) 2.0))) 2e+126)
               (* (sqrt (/ (* n PI) k)) (sqrt 2.0))
               (/ (* (sqrt (* k (* n PI))) (sqrt 2.0)) k)))
            double code(double k, double n) {
            	double tmp;
            	if (((1.0 / sqrt(k)) * pow(((2.0 * ((double) M_PI)) * n), ((1.0 - k) / 2.0))) <= 2e+126) {
            		tmp = sqrt(((n * ((double) M_PI)) / k)) * sqrt(2.0);
            	} else {
            		tmp = (sqrt((k * (n * ((double) M_PI)))) * sqrt(2.0)) / k;
            	}
            	return tmp;
            }
            
            public static double code(double k, double n) {
            	double tmp;
            	if (((1.0 / Math.sqrt(k)) * Math.pow(((2.0 * Math.PI) * n), ((1.0 - k) / 2.0))) <= 2e+126) {
            		tmp = Math.sqrt(((n * Math.PI) / k)) * Math.sqrt(2.0);
            	} else {
            		tmp = (Math.sqrt((k * (n * Math.PI))) * Math.sqrt(2.0)) / k;
            	}
            	return tmp;
            }
            
            def code(k, n):
            	tmp = 0
            	if ((1.0 / math.sqrt(k)) * math.pow(((2.0 * math.pi) * n), ((1.0 - k) / 2.0))) <= 2e+126:
            		tmp = math.sqrt(((n * math.pi) / k)) * math.sqrt(2.0)
            	else:
            		tmp = (math.sqrt((k * (n * math.pi))) * math.sqrt(2.0)) / k
            	return tmp
            
            function code(k, n)
            	tmp = 0.0
            	if (Float64(Float64(1.0 / sqrt(k)) * (Float64(Float64(2.0 * pi) * n) ^ Float64(Float64(1.0 - k) / 2.0))) <= 2e+126)
            		tmp = Float64(sqrt(Float64(Float64(n * pi) / k)) * sqrt(2.0));
            	else
            		tmp = Float64(Float64(sqrt(Float64(k * Float64(n * pi))) * sqrt(2.0)) / k);
            	end
            	return tmp
            end
            
            function tmp_2 = code(k, n)
            	tmp = 0.0;
            	if (((1.0 / sqrt(k)) * (((2.0 * pi) * n) ^ ((1.0 - k) / 2.0))) <= 2e+126)
            		tmp = sqrt(((n * pi) / k)) * sqrt(2.0);
            	else
            		tmp = (sqrt((k * (n * pi))) * sqrt(2.0)) / k;
            	end
            	tmp_2 = tmp;
            end
            
            code[k_, n_] := If[LessEqual[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], 2e+126], N[(N[Sqrt[N[(N[(n * Pi), $MachinePrecision] / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision], N[(N[(N[Sqrt[N[(k * N[(n * Pi), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision] / k), $MachinePrecision]]
            
            \begin{array}{l}
            
            \\
            \begin{array}{l}
            \mathbf{if}\;\frac{1}{\sqrt{k}} \cdot {\left(\left(2 \cdot \pi\right) \cdot n\right)}^{\left(\frac{1 - k}{2}\right)} \leq 2 \cdot 10^{+126}:\\
            \;\;\;\;\sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2}\\
            
            \mathbf{else}:\\
            \;\;\;\;\frac{\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}}{k}\\
            
            
            \end{array}
            \end{array}
            
            Derivation
            1. Split input into 2 regimes
            2. if (*.f64 (/.f64 #s(literal 1 binary64) (sqrt.f64 k)) (pow.f64 (*.f64 (*.f64 #s(literal 2 binary64) (PI.f64)) n) (/.f64 (-.f64 #s(literal 1 binary64) k) #s(literal 2 binary64)))) < 1.99999999999999985e126

              1. Initial program 99.3%

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

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

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

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

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

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

                  \[\leadsto \sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2} \]
                6. lower-sqrt.f6456.3

                  \[\leadsto \sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2} \]
              4. Applied rewrites56.3%

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

              if 1.99999999999999985e126 < (*.f64 (/.f64 #s(literal 1 binary64) (sqrt.f64 k)) (pow.f64 (*.f64 (*.f64 #s(literal 2 binary64) (PI.f64)) n) (/.f64 (-.f64 #s(literal 1 binary64) k) #s(literal 2 binary64))))

              1. Initial program 99.5%

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

                \[\leadsto \color{blue}{\frac{k \cdot \left(\frac{-1}{2} \cdot \left(\sqrt{k \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \left(\log \left(2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)\right) \cdot \sqrt{2}\right)\right) + k \cdot \left(\frac{-1}{48} \cdot \left(\sqrt{{k}^{3} \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)\right)}^{3} \cdot \sqrt{2}\right)\right) + \frac{1}{8} \cdot \left(\sqrt{k \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)\right)}^{2} \cdot \sqrt{2}\right)\right)\right)\right) + \sqrt{k \cdot \left(n \cdot \mathsf{PI}\left(\right)\right)} \cdot \sqrt{2}}{k}} \]
              3. Applied rewrites81.3%

                \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(k, \mathsf{fma}\left(-0.5, \sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \left(\log \left(2 \cdot \left(n \cdot \pi\right)\right) \cdot \sqrt{2}\right), k \cdot \mathsf{fma}\left(-0.020833333333333332, \sqrt{{k}^{3} \cdot \left(n \cdot \pi\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \pi\right)\right)}^{3} \cdot \sqrt{2}\right), 0.125 \cdot \left(\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \left({\log \left(2 \cdot \left(n \cdot \pi\right)\right)}^{2} \cdot \sqrt{2}\right)\right)\right)\right), \sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}\right)}{k}} \]
              4. Taylor expanded in k around 0

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

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

                  \[\leadsto \frac{\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}}{k} \]
                3. lift-*.f64N/A

                  \[\leadsto \frac{\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}}{k} \]
                4. lift-sqrt.f64N/A

                  \[\leadsto \frac{\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}}{k} \]
                5. lift-sqrt.f64N/A

                  \[\leadsto \frac{\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}}{k} \]
                6. lift-*.f6440.0

                  \[\leadsto \frac{\sqrt{k \cdot \left(n \cdot \pi\right)} \cdot \sqrt{2}}{k} \]
              6. Applied rewrites40.0%

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

            Alternative 7: 37.9% accurate, 2.7× speedup?

            \[\begin{array}{l} \\ \sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2} \end{array} \]
            (FPCore (k n) :precision binary64 (* (sqrt (/ (* n PI) k)) (sqrt 2.0)))
            double code(double k, double n) {
            	return sqrt(((n * ((double) M_PI)) / k)) * sqrt(2.0);
            }
            
            public static double code(double k, double n) {
            	return Math.sqrt(((n * Math.PI) / k)) * Math.sqrt(2.0);
            }
            
            def code(k, n):
            	return math.sqrt(((n * math.pi) / k)) * math.sqrt(2.0)
            
            function code(k, n)
            	return Float64(sqrt(Float64(Float64(n * pi) / k)) * sqrt(2.0))
            end
            
            function tmp = code(k, n)
            	tmp = sqrt(((n * pi) / k)) * sqrt(2.0);
            end
            
            code[k_, n_] := N[(N[Sqrt[N[(N[(n * Pi), $MachinePrecision] / k), $MachinePrecision]], $MachinePrecision] * N[Sqrt[2.0], $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2}
            \end{array}
            
            Derivation
            1. Initial program 99.4%

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

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

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

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

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

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

                \[\leadsto \sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2} \]
              6. lower-sqrt.f6437.9

                \[\leadsto \sqrt{\frac{n \cdot \pi}{k}} \cdot \sqrt{2} \]
            4. Applied rewrites37.9%

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

            Reproduce

            ?
            herbie shell --seed 2025128 
            (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))))