2nthrt (problem 3.4.6)

Percentage Accurate: 52.9% → 84.5%
Time: 28.7s
Alternatives: 12
Speedup: 1.9×

Specification

?
\[\begin{array}{l} \\ {\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \end{array} \]
(FPCore (x n)
 :precision binary64
 (- (pow (+ x 1.0) (/ 1.0 n)) (pow x (/ 1.0 n))))
double code(double x, double n) {
	return pow((x + 1.0), (1.0 / n)) - pow(x, (1.0 / n));
}
real(8) function code(x, n)
    real(8), intent (in) :: x
    real(8), intent (in) :: n
    code = ((x + 1.0d0) ** (1.0d0 / n)) - (x ** (1.0d0 / n))
end function
public static double code(double x, double n) {
	return Math.pow((x + 1.0), (1.0 / n)) - Math.pow(x, (1.0 / n));
}
def code(x, n):
	return math.pow((x + 1.0), (1.0 / n)) - math.pow(x, (1.0 / n))
function code(x, n)
	return Float64((Float64(x + 1.0) ^ Float64(1.0 / n)) - (x ^ Float64(1.0 / n)))
end
function tmp = code(x, n)
	tmp = ((x + 1.0) ^ (1.0 / n)) - (x ^ (1.0 / n));
end
code[x_, n_] := N[(N[Power[N[(x + 1.0), $MachinePrecision], N[(1.0 / n), $MachinePrecision]], $MachinePrecision] - N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\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 12 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: 52.9% accurate, 1.0× speedup?

\[\begin{array}{l} \\ {\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \end{array} \]
(FPCore (x n)
 :precision binary64
 (- (pow (+ x 1.0) (/ 1.0 n)) (pow x (/ 1.0 n))))
double code(double x, double n) {
	return pow((x + 1.0), (1.0 / n)) - pow(x, (1.0 / n));
}
real(8) function code(x, n)
    real(8), intent (in) :: x
    real(8), intent (in) :: n
    code = ((x + 1.0d0) ** (1.0d0 / n)) - (x ** (1.0d0 / n))
end function
public static double code(double x, double n) {
	return Math.pow((x + 1.0), (1.0 / n)) - Math.pow(x, (1.0 / n));
}
def code(x, n):
	return math.pow((x + 1.0), (1.0 / n)) - math.pow(x, (1.0 / n))
function code(x, n)
	return Float64((Float64(x + 1.0) ^ Float64(1.0 / n)) - (x ^ Float64(1.0 / n)))
end
function tmp = code(x, n)
	tmp = ((x + 1.0) ^ (1.0 / n)) - (x ^ (1.0 / n));
end
code[x_, n_] := N[(N[Power[N[(x + 1.0), $MachinePrecision], N[(1.0 / n), $MachinePrecision]], $MachinePrecision] - N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)}
\end{array}

Alternative 1: 84.5% accurate, 0.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{log1p}\left(x\right) - \log x\\ t_1 := {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;\frac{1}{n} \cdot t_0\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\left(\frac{1}{x} + \frac{0.3333333333333333}{{x}^{3}}\right) - \left(\frac{0.5}{{x}^{2}} + \frac{0.25}{{x}^{4}}\right)}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;\frac{t_0}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{t_1}{n}}{x}\\ \mathbf{else}:\\ \;\;\;\;e^{\frac{x}{n}} - t_1\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (let* ((t_0 (- (log1p x) (log x))) (t_1 (pow x (/ 1.0 n))))
   (if (<= (/ 1.0 n) -5e-19)
     (* t_1 (/ (/ 1.0 x) n))
     (if (<= (/ 1.0 n) -1e-137)
       (* (/ 1.0 n) t_0)
       (if (<= (/ 1.0 n) -2e-154)
         (/
          (-
           (+ (/ 1.0 x) (/ 0.3333333333333333 (pow x 3.0)))
           (+ (/ 0.5 (pow x 2.0)) (/ 0.25 (pow x 4.0))))
          n)
         (if (<= (/ 1.0 n) 2e-150)
           (/ t_0 n)
           (if (<= (/ 1.0 n) 100000.0)
             (/ (/ t_1 n) x)
             (- (exp (/ x n)) t_1))))))))
double code(double x, double n) {
	double t_0 = log1p(x) - log(x);
	double t_1 = pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = (1.0 / n) * t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = (((1.0 / x) + (0.3333333333333333 / pow(x, 3.0))) - ((0.5 / pow(x, 2.0)) + (0.25 / pow(x, 4.0)))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0 / n;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else {
		tmp = exp((x / n)) - t_1;
	}
	return tmp;
}
public static double code(double x, double n) {
	double t_0 = Math.log1p(x) - Math.log(x);
	double t_1 = Math.pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = (1.0 / n) * t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = (((1.0 / x) + (0.3333333333333333 / Math.pow(x, 3.0))) - ((0.5 / Math.pow(x, 2.0)) + (0.25 / Math.pow(x, 4.0)))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0 / n;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else {
		tmp = Math.exp((x / n)) - t_1;
	}
	return tmp;
}
def code(x, n):
	t_0 = math.log1p(x) - math.log(x)
	t_1 = math.pow(x, (1.0 / n))
	tmp = 0
	if (1.0 / n) <= -5e-19:
		tmp = t_1 * ((1.0 / x) / n)
	elif (1.0 / n) <= -1e-137:
		tmp = (1.0 / n) * t_0
	elif (1.0 / n) <= -2e-154:
		tmp = (((1.0 / x) + (0.3333333333333333 / math.pow(x, 3.0))) - ((0.5 / math.pow(x, 2.0)) + (0.25 / math.pow(x, 4.0)))) / n
	elif (1.0 / n) <= 2e-150:
		tmp = t_0 / n
	elif (1.0 / n) <= 100000.0:
		tmp = (t_1 / n) / x
	else:
		tmp = math.exp((x / n)) - t_1
	return tmp
function code(x, n)
	t_0 = Float64(log1p(x) - log(x))
	t_1 = x ^ Float64(1.0 / n)
	tmp = 0.0
	if (Float64(1.0 / n) <= -5e-19)
		tmp = Float64(t_1 * Float64(Float64(1.0 / x) / n));
	elseif (Float64(1.0 / n) <= -1e-137)
		tmp = Float64(Float64(1.0 / n) * t_0);
	elseif (Float64(1.0 / n) <= -2e-154)
		tmp = Float64(Float64(Float64(Float64(1.0 / x) + Float64(0.3333333333333333 / (x ^ 3.0))) - Float64(Float64(0.5 / (x ^ 2.0)) + Float64(0.25 / (x ^ 4.0)))) / n);
	elseif (Float64(1.0 / n) <= 2e-150)
		tmp = Float64(t_0 / n);
	elseif (Float64(1.0 / n) <= 100000.0)
		tmp = Float64(Float64(t_1 / n) / x);
	else
		tmp = Float64(exp(Float64(x / n)) - t_1);
	end
	return tmp
end
code[x_, n_] := Block[{t$95$0 = N[(N[Log[1 + x], $MachinePrecision] - N[Log[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[N[(1.0 / n), $MachinePrecision], -5e-19], N[(t$95$1 * N[(N[(1.0 / x), $MachinePrecision] / n), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], -1e-137], N[(N[(1.0 / n), $MachinePrecision] * t$95$0), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], -2e-154], N[(N[(N[(N[(1.0 / x), $MachinePrecision] + N[(0.3333333333333333 / N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] - N[(N[(0.5 / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision] + N[(0.25 / N[Power[x, 4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / n), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 2e-150], N[(t$95$0 / n), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 100000.0], N[(N[(t$95$1 / n), $MachinePrecision] / x), $MachinePrecision], N[(N[Exp[N[(x / n), $MachinePrecision]], $MachinePrecision] - t$95$1), $MachinePrecision]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{log1p}\left(x\right) - \log x\\
t_1 := {x}^{\left(\frac{1}{n}\right)}\\
\mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\
\;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\
\;\;\;\;\frac{1}{n} \cdot t_0\\

\mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\
\;\;\;\;\frac{\left(\frac{1}{x} + \frac{0.3333333333333333}{{x}^{3}}\right) - \left(\frac{0.5}{{x}^{2}} + \frac{0.25}{{x}^{4}}\right)}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\
\;\;\;\;\frac{t_0}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq 100000:\\
\;\;\;\;\frac{\frac{t_1}{n}}{x}\\

\mathbf{else}:\\
\;\;\;\;e^{\frac{x}{n}} - t_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 6 regimes
  2. if (/.f64 1 n) < -5.0000000000000004e-19

    1. Initial program 97.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 98.8%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg98.8%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac98.8%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg98.8%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg98.8%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative98.8%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified98.8%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. div-inv98.8%

        \[\leadsto \color{blue}{e^{\frac{\log x}{n}} \cdot \frac{1}{x \cdot n}} \]
      2. associate-/r*98.8%

        \[\leadsto e^{\frac{\log x}{n}} \cdot \color{blue}{\frac{\frac{1}{x}}{n}} \]
      3. div-inv98.8%

        \[\leadsto e^{\color{blue}{\log x \cdot \frac{1}{n}}} \cdot \frac{\frac{1}{x}}{n} \]
      4. exp-to-pow98.8%

        \[\leadsto \color{blue}{{x}^{\left(\frac{1}{n}\right)}} \cdot \frac{\frac{1}{x}}{n} \]
    6. Applied egg-rr98.8%

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

    if -5.0000000000000004e-19 < (/.f64 1 n) < -9.99999999999999978e-138

    1. Initial program 14.1%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 76.8%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def76.8%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified76.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Step-by-step derivation
      1. div-sub76.8%

        \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} - \frac{\log x}{n}} \]
    6. Applied egg-rr76.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} - \frac{\log x}{n}} \]
    7. Step-by-step derivation
      1. div-inv73.9%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(x\right) \cdot \frac{1}{n}} - \frac{\log x}{n} \]
      2. div-inv76.8%

        \[\leadsto \mathsf{log1p}\left(x\right) \cdot \frac{1}{n} - \color{blue}{\log x \cdot \frac{1}{n}} \]
      3. distribute-rgt-out--76.8%

        \[\leadsto \color{blue}{\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)} \]
    8. Applied egg-rr76.8%

      \[\leadsto \color{blue}{\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)} \]

    if -9.99999999999999978e-138 < (/.f64 1 n) < -1.9999999999999999e-154

    1. Initial program 22.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 39.7%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def39.7%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified39.7%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 86.8%

      \[\leadsto \frac{\color{blue}{\left(0.3333333333333333 \cdot \frac{1}{{x}^{3}} + \frac{1}{x}\right) - \left(0.25 \cdot \frac{1}{{x}^{4}} + 0.5 \cdot \frac{1}{{x}^{2}}\right)}}{n} \]
    6. Step-by-step derivation
      1. +-commutative86.8%

        \[\leadsto \frac{\color{blue}{\left(\frac{1}{x} + 0.3333333333333333 \cdot \frac{1}{{x}^{3}}\right)} - \left(0.25 \cdot \frac{1}{{x}^{4}} + 0.5 \cdot \frac{1}{{x}^{2}}\right)}{n} \]
      2. associate-*r/86.8%

        \[\leadsto \frac{\left(\frac{1}{x} + \color{blue}{\frac{0.3333333333333333 \cdot 1}{{x}^{3}}}\right) - \left(0.25 \cdot \frac{1}{{x}^{4}} + 0.5 \cdot \frac{1}{{x}^{2}}\right)}{n} \]
      3. metadata-eval86.8%

        \[\leadsto \frac{\left(\frac{1}{x} + \frac{\color{blue}{0.3333333333333333}}{{x}^{3}}\right) - \left(0.25 \cdot \frac{1}{{x}^{4}} + 0.5 \cdot \frac{1}{{x}^{2}}\right)}{n} \]
      4. +-commutative86.8%

        \[\leadsto \frac{\left(\frac{1}{x} + \frac{0.3333333333333333}{{x}^{3}}\right) - \color{blue}{\left(0.5 \cdot \frac{1}{{x}^{2}} + 0.25 \cdot \frac{1}{{x}^{4}}\right)}}{n} \]
      5. associate-*r/86.8%

        \[\leadsto \frac{\left(\frac{1}{x} + \frac{0.3333333333333333}{{x}^{3}}\right) - \left(\color{blue}{\frac{0.5 \cdot 1}{{x}^{2}}} + 0.25 \cdot \frac{1}{{x}^{4}}\right)}{n} \]
      6. metadata-eval86.8%

        \[\leadsto \frac{\left(\frac{1}{x} + \frac{0.3333333333333333}{{x}^{3}}\right) - \left(\frac{\color{blue}{0.5}}{{x}^{2}} + 0.25 \cdot \frac{1}{{x}^{4}}\right)}{n} \]
      7. associate-*r/86.8%

        \[\leadsto \frac{\left(\frac{1}{x} + \frac{0.3333333333333333}{{x}^{3}}\right) - \left(\frac{0.5}{{x}^{2}} + \color{blue}{\frac{0.25 \cdot 1}{{x}^{4}}}\right)}{n} \]
      8. metadata-eval86.8%

        \[\leadsto \frac{\left(\frac{1}{x} + \frac{0.3333333333333333}{{x}^{3}}\right) - \left(\frac{0.5}{{x}^{2}} + \frac{\color{blue}{0.25}}{{x}^{4}}\right)}{n} \]
    7. Simplified86.8%

      \[\leadsto \frac{\color{blue}{\left(\frac{1}{x} + \frac{0.3333333333333333}{{x}^{3}}\right) - \left(\frac{0.5}{{x}^{2}} + \frac{0.25}{{x}^{4}}\right)}}{n} \]

    if -1.9999999999999999e-154 < (/.f64 1 n) < 2.00000000000000001e-150

    1. Initial program 40.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 96.5%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def96.5%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified96.5%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]

    if 2.00000000000000001e-150 < (/.f64 1 n) < 1e5

    1. Initial program 18.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 76.7%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg76.7%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac76.7%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg76.7%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg76.7%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative76.7%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified76.7%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. *-un-lft-identity76.7%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{\frac{\log x}{n}}}}{x \cdot n} \]
      2. times-frac76.7%

        \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{e^{\frac{\log x}{n}}}{n}} \]
      3. div-inv76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{e^{\color{blue}{\log x \cdot \frac{1}{n}}}}{n} \]
      4. exp-to-pow76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{\color{blue}{{x}^{\left(\frac{1}{n}\right)}}}{n} \]
    6. Applied egg-rr76.7%

      \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}} \]
    7. Step-by-step derivation
      1. associate-*l/76.9%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]
      2. *-un-lft-identity76.9%

        \[\leadsto \frac{\color{blue}{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}}{x} \]
    8. Applied egg-rr76.9%

      \[\leadsto \color{blue}{\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]

    if 1e5 < (/.f64 1 n)

    1. Initial program 60.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around 0 60.0%

      \[\leadsto \color{blue}{e^{\frac{\log \left(1 + x\right)}{n}}} - {x}^{\left(\frac{1}{n}\right)} \]
    3. Step-by-step derivation
      1. log1p-def100.0%

        \[\leadsto e^{\frac{\color{blue}{\mathsf{log1p}\left(x\right)}}{n}} - {x}^{\left(\frac{1}{n}\right)} \]
    4. Simplified100.0%

      \[\leadsto \color{blue}{e^{\frac{\mathsf{log1p}\left(x\right)}{n}}} - {x}^{\left(\frac{1}{n}\right)} \]
    5. Taylor expanded in x around 0 100.0%

      \[\leadsto e^{\color{blue}{\frac{x}{n}}} - {x}^{\left(\frac{1}{n}\right)} \]
  3. Recombined 6 regimes into one program.
  4. Final simplification92.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;{x}^{\left(\frac{1}{n}\right)} \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\left(\frac{1}{x} + \frac{0.3333333333333333}{{x}^{3}}\right) - \left(\frac{0.5}{{x}^{2}} + \frac{0.25}{{x}^{4}}\right)}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;\frac{\mathsf{log1p}\left(x\right) - \log x}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}\\ \mathbf{else}:\\ \;\;\;\;e^{\frac{x}{n}} - {x}^{\left(\frac{1}{n}\right)}\\ \end{array} \]

Alternative 2: 84.4% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{log1p}\left(x\right) - \log x\\ t_1 := {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;\frac{1}{n} \cdot t_0\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\frac{1}{x} - \frac{0.5}{{x}^{2}}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;\frac{t_0}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{t_1}{n}}{x}\\ \mathbf{else}:\\ \;\;\;\;e^{\frac{x}{n}} - t_1\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (let* ((t_0 (- (log1p x) (log x))) (t_1 (pow x (/ 1.0 n))))
   (if (<= (/ 1.0 n) -5e-19)
     (* t_1 (/ (/ 1.0 x) n))
     (if (<= (/ 1.0 n) -1e-137)
       (* (/ 1.0 n) t_0)
       (if (<= (/ 1.0 n) -2e-154)
         (/ (- (/ 1.0 x) (/ 0.5 (pow x 2.0))) n)
         (if (<= (/ 1.0 n) 2e-150)
           (/ t_0 n)
           (if (<= (/ 1.0 n) 100000.0)
             (/ (/ t_1 n) x)
             (- (exp (/ x n)) t_1))))))))
double code(double x, double n) {
	double t_0 = log1p(x) - log(x);
	double t_1 = pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = (1.0 / n) * t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = ((1.0 / x) - (0.5 / pow(x, 2.0))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0 / n;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else {
		tmp = exp((x / n)) - t_1;
	}
	return tmp;
}
public static double code(double x, double n) {
	double t_0 = Math.log1p(x) - Math.log(x);
	double t_1 = Math.pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = (1.0 / n) * t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = ((1.0 / x) - (0.5 / Math.pow(x, 2.0))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0 / n;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else {
		tmp = Math.exp((x / n)) - t_1;
	}
	return tmp;
}
def code(x, n):
	t_0 = math.log1p(x) - math.log(x)
	t_1 = math.pow(x, (1.0 / n))
	tmp = 0
	if (1.0 / n) <= -5e-19:
		tmp = t_1 * ((1.0 / x) / n)
	elif (1.0 / n) <= -1e-137:
		tmp = (1.0 / n) * t_0
	elif (1.0 / n) <= -2e-154:
		tmp = ((1.0 / x) - (0.5 / math.pow(x, 2.0))) / n
	elif (1.0 / n) <= 2e-150:
		tmp = t_0 / n
	elif (1.0 / n) <= 100000.0:
		tmp = (t_1 / n) / x
	else:
		tmp = math.exp((x / n)) - t_1
	return tmp
function code(x, n)
	t_0 = Float64(log1p(x) - log(x))
	t_1 = x ^ Float64(1.0 / n)
	tmp = 0.0
	if (Float64(1.0 / n) <= -5e-19)
		tmp = Float64(t_1 * Float64(Float64(1.0 / x) / n));
	elseif (Float64(1.0 / n) <= -1e-137)
		tmp = Float64(Float64(1.0 / n) * t_0);
	elseif (Float64(1.0 / n) <= -2e-154)
		tmp = Float64(Float64(Float64(1.0 / x) - Float64(0.5 / (x ^ 2.0))) / n);
	elseif (Float64(1.0 / n) <= 2e-150)
		tmp = Float64(t_0 / n);
	elseif (Float64(1.0 / n) <= 100000.0)
		tmp = Float64(Float64(t_1 / n) / x);
	else
		tmp = Float64(exp(Float64(x / n)) - t_1);
	end
	return tmp
end
code[x_, n_] := Block[{t$95$0 = N[(N[Log[1 + x], $MachinePrecision] - N[Log[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[N[(1.0 / n), $MachinePrecision], -5e-19], N[(t$95$1 * N[(N[(1.0 / x), $MachinePrecision] / n), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], -1e-137], N[(N[(1.0 / n), $MachinePrecision] * t$95$0), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], -2e-154], N[(N[(N[(1.0 / x), $MachinePrecision] - N[(0.5 / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / n), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 2e-150], N[(t$95$0 / n), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 100000.0], N[(N[(t$95$1 / n), $MachinePrecision] / x), $MachinePrecision], N[(N[Exp[N[(x / n), $MachinePrecision]], $MachinePrecision] - t$95$1), $MachinePrecision]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{log1p}\left(x\right) - \log x\\
t_1 := {x}^{\left(\frac{1}{n}\right)}\\
\mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\
\;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\
\;\;\;\;\frac{1}{n} \cdot t_0\\

\mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\
\;\;\;\;\frac{\frac{1}{x} - \frac{0.5}{{x}^{2}}}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\
\;\;\;\;\frac{t_0}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq 100000:\\
\;\;\;\;\frac{\frac{t_1}{n}}{x}\\

\mathbf{else}:\\
\;\;\;\;e^{\frac{x}{n}} - t_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 6 regimes
  2. if (/.f64 1 n) < -5.0000000000000004e-19

    1. Initial program 97.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 98.8%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg98.8%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac98.8%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg98.8%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg98.8%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative98.8%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified98.8%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. div-inv98.8%

        \[\leadsto \color{blue}{e^{\frac{\log x}{n}} \cdot \frac{1}{x \cdot n}} \]
      2. associate-/r*98.8%

        \[\leadsto e^{\frac{\log x}{n}} \cdot \color{blue}{\frac{\frac{1}{x}}{n}} \]
      3. div-inv98.8%

        \[\leadsto e^{\color{blue}{\log x \cdot \frac{1}{n}}} \cdot \frac{\frac{1}{x}}{n} \]
      4. exp-to-pow98.8%

        \[\leadsto \color{blue}{{x}^{\left(\frac{1}{n}\right)}} \cdot \frac{\frac{1}{x}}{n} \]
    6. Applied egg-rr98.8%

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

    if -5.0000000000000004e-19 < (/.f64 1 n) < -9.99999999999999978e-138

    1. Initial program 14.1%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 76.8%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def76.8%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified76.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Step-by-step derivation
      1. div-sub76.8%

        \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} - \frac{\log x}{n}} \]
    6. Applied egg-rr76.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} - \frac{\log x}{n}} \]
    7. Step-by-step derivation
      1. div-inv73.9%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(x\right) \cdot \frac{1}{n}} - \frac{\log x}{n} \]
      2. div-inv76.8%

        \[\leadsto \mathsf{log1p}\left(x\right) \cdot \frac{1}{n} - \color{blue}{\log x \cdot \frac{1}{n}} \]
      3. distribute-rgt-out--76.8%

        \[\leadsto \color{blue}{\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)} \]
    8. Applied egg-rr76.8%

      \[\leadsto \color{blue}{\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)} \]

    if -9.99999999999999978e-138 < (/.f64 1 n) < -1.9999999999999999e-154

    1. Initial program 22.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 39.7%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def39.7%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified39.7%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 84.4%

      \[\leadsto \frac{\color{blue}{\frac{1}{x} - 0.5 \cdot \frac{1}{{x}^{2}}}}{n} \]
    6. Step-by-step derivation
      1. associate-*r/84.4%

        \[\leadsto \frac{\frac{1}{x} - \color{blue}{\frac{0.5 \cdot 1}{{x}^{2}}}}{n} \]
      2. metadata-eval84.4%

        \[\leadsto \frac{\frac{1}{x} - \frac{\color{blue}{0.5}}{{x}^{2}}}{n} \]
    7. Simplified84.4%

      \[\leadsto \frac{\color{blue}{\frac{1}{x} - \frac{0.5}{{x}^{2}}}}{n} \]

    if -1.9999999999999999e-154 < (/.f64 1 n) < 2.00000000000000001e-150

    1. Initial program 40.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 96.5%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def96.5%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified96.5%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]

    if 2.00000000000000001e-150 < (/.f64 1 n) < 1e5

    1. Initial program 18.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 76.7%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg76.7%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac76.7%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg76.7%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg76.7%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative76.7%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified76.7%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. *-un-lft-identity76.7%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{\frac{\log x}{n}}}}{x \cdot n} \]
      2. times-frac76.7%

        \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{e^{\frac{\log x}{n}}}{n}} \]
      3. div-inv76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{e^{\color{blue}{\log x \cdot \frac{1}{n}}}}{n} \]
      4. exp-to-pow76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{\color{blue}{{x}^{\left(\frac{1}{n}\right)}}}{n} \]
    6. Applied egg-rr76.7%

      \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}} \]
    7. Step-by-step derivation
      1. associate-*l/76.9%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]
      2. *-un-lft-identity76.9%

        \[\leadsto \frac{\color{blue}{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}}{x} \]
    8. Applied egg-rr76.9%

      \[\leadsto \color{blue}{\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]

    if 1e5 < (/.f64 1 n)

    1. Initial program 60.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around 0 60.0%

      \[\leadsto \color{blue}{e^{\frac{\log \left(1 + x\right)}{n}}} - {x}^{\left(\frac{1}{n}\right)} \]
    3. Step-by-step derivation
      1. log1p-def100.0%

        \[\leadsto e^{\frac{\color{blue}{\mathsf{log1p}\left(x\right)}}{n}} - {x}^{\left(\frac{1}{n}\right)} \]
    4. Simplified100.0%

      \[\leadsto \color{blue}{e^{\frac{\mathsf{log1p}\left(x\right)}{n}}} - {x}^{\left(\frac{1}{n}\right)} \]
    5. Taylor expanded in x around 0 100.0%

      \[\leadsto e^{\color{blue}{\frac{x}{n}}} - {x}^{\left(\frac{1}{n}\right)} \]
  3. Recombined 6 regimes into one program.
  4. Final simplification92.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;{x}^{\left(\frac{1}{n}\right)} \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\frac{1}{x} - \frac{0.5}{{x}^{2}}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;\frac{\mathsf{log1p}\left(x\right) - \log x}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}\\ \mathbf{else}:\\ \;\;\;\;e^{\frac{x}{n}} - {x}^{\left(\frac{1}{n}\right)}\\ \end{array} \]

Alternative 3: 84.5% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{log1p}\left(x\right) - \log x\\ t_1 := {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;\frac{1}{n} \cdot t_0\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\frac{0.3333333333333333}{{x}^{3}} + \left(\frac{1}{x} - \frac{0.5}{{x}^{2}}\right)}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;\frac{t_0}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{t_1}{n}}{x}\\ \mathbf{else}:\\ \;\;\;\;e^{\frac{x}{n}} - t_1\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (let* ((t_0 (- (log1p x) (log x))) (t_1 (pow x (/ 1.0 n))))
   (if (<= (/ 1.0 n) -5e-19)
     (* t_1 (/ (/ 1.0 x) n))
     (if (<= (/ 1.0 n) -1e-137)
       (* (/ 1.0 n) t_0)
       (if (<= (/ 1.0 n) -2e-154)
         (/
          (+
           (/ 0.3333333333333333 (pow x 3.0))
           (- (/ 1.0 x) (/ 0.5 (pow x 2.0))))
          n)
         (if (<= (/ 1.0 n) 2e-150)
           (/ t_0 n)
           (if (<= (/ 1.0 n) 100000.0)
             (/ (/ t_1 n) x)
             (- (exp (/ x n)) t_1))))))))
double code(double x, double n) {
	double t_0 = log1p(x) - log(x);
	double t_1 = pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = (1.0 / n) * t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = ((0.3333333333333333 / pow(x, 3.0)) + ((1.0 / x) - (0.5 / pow(x, 2.0)))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0 / n;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else {
		tmp = exp((x / n)) - t_1;
	}
	return tmp;
}
public static double code(double x, double n) {
	double t_0 = Math.log1p(x) - Math.log(x);
	double t_1 = Math.pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = (1.0 / n) * t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = ((0.3333333333333333 / Math.pow(x, 3.0)) + ((1.0 / x) - (0.5 / Math.pow(x, 2.0)))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0 / n;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else {
		tmp = Math.exp((x / n)) - t_1;
	}
	return tmp;
}
def code(x, n):
	t_0 = math.log1p(x) - math.log(x)
	t_1 = math.pow(x, (1.0 / n))
	tmp = 0
	if (1.0 / n) <= -5e-19:
		tmp = t_1 * ((1.0 / x) / n)
	elif (1.0 / n) <= -1e-137:
		tmp = (1.0 / n) * t_0
	elif (1.0 / n) <= -2e-154:
		tmp = ((0.3333333333333333 / math.pow(x, 3.0)) + ((1.0 / x) - (0.5 / math.pow(x, 2.0)))) / n
	elif (1.0 / n) <= 2e-150:
		tmp = t_0 / n
	elif (1.0 / n) <= 100000.0:
		tmp = (t_1 / n) / x
	else:
		tmp = math.exp((x / n)) - t_1
	return tmp
function code(x, n)
	t_0 = Float64(log1p(x) - log(x))
	t_1 = x ^ Float64(1.0 / n)
	tmp = 0.0
	if (Float64(1.0 / n) <= -5e-19)
		tmp = Float64(t_1 * Float64(Float64(1.0 / x) / n));
	elseif (Float64(1.0 / n) <= -1e-137)
		tmp = Float64(Float64(1.0 / n) * t_0);
	elseif (Float64(1.0 / n) <= -2e-154)
		tmp = Float64(Float64(Float64(0.3333333333333333 / (x ^ 3.0)) + Float64(Float64(1.0 / x) - Float64(0.5 / (x ^ 2.0)))) / n);
	elseif (Float64(1.0 / n) <= 2e-150)
		tmp = Float64(t_0 / n);
	elseif (Float64(1.0 / n) <= 100000.0)
		tmp = Float64(Float64(t_1 / n) / x);
	else
		tmp = Float64(exp(Float64(x / n)) - t_1);
	end
	return tmp
end
code[x_, n_] := Block[{t$95$0 = N[(N[Log[1 + x], $MachinePrecision] - N[Log[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[N[(1.0 / n), $MachinePrecision], -5e-19], N[(t$95$1 * N[(N[(1.0 / x), $MachinePrecision] / n), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], -1e-137], N[(N[(1.0 / n), $MachinePrecision] * t$95$0), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], -2e-154], N[(N[(N[(0.3333333333333333 / N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision] + N[(N[(1.0 / x), $MachinePrecision] - N[(0.5 / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / n), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 2e-150], N[(t$95$0 / n), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 100000.0], N[(N[(t$95$1 / n), $MachinePrecision] / x), $MachinePrecision], N[(N[Exp[N[(x / n), $MachinePrecision]], $MachinePrecision] - t$95$1), $MachinePrecision]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{log1p}\left(x\right) - \log x\\
t_1 := {x}^{\left(\frac{1}{n}\right)}\\
\mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\
\;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\
\;\;\;\;\frac{1}{n} \cdot t_0\\

\mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\
\;\;\;\;\frac{\frac{0.3333333333333333}{{x}^{3}} + \left(\frac{1}{x} - \frac{0.5}{{x}^{2}}\right)}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\
\;\;\;\;\frac{t_0}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq 100000:\\
\;\;\;\;\frac{\frac{t_1}{n}}{x}\\

\mathbf{else}:\\
\;\;\;\;e^{\frac{x}{n}} - t_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 6 regimes
  2. if (/.f64 1 n) < -5.0000000000000004e-19

    1. Initial program 97.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 98.8%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg98.8%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac98.8%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg98.8%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg98.8%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative98.8%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified98.8%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. div-inv98.8%

        \[\leadsto \color{blue}{e^{\frac{\log x}{n}} \cdot \frac{1}{x \cdot n}} \]
      2. associate-/r*98.8%

        \[\leadsto e^{\frac{\log x}{n}} \cdot \color{blue}{\frac{\frac{1}{x}}{n}} \]
      3. div-inv98.8%

        \[\leadsto e^{\color{blue}{\log x \cdot \frac{1}{n}}} \cdot \frac{\frac{1}{x}}{n} \]
      4. exp-to-pow98.8%

        \[\leadsto \color{blue}{{x}^{\left(\frac{1}{n}\right)}} \cdot \frac{\frac{1}{x}}{n} \]
    6. Applied egg-rr98.8%

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

    if -5.0000000000000004e-19 < (/.f64 1 n) < -9.99999999999999978e-138

    1. Initial program 14.1%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 76.8%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def76.8%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified76.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Step-by-step derivation
      1. div-sub76.8%

        \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} - \frac{\log x}{n}} \]
    6. Applied egg-rr76.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} - \frac{\log x}{n}} \]
    7. Step-by-step derivation
      1. div-inv73.9%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(x\right) \cdot \frac{1}{n}} - \frac{\log x}{n} \]
      2. div-inv76.8%

        \[\leadsto \mathsf{log1p}\left(x\right) \cdot \frac{1}{n} - \color{blue}{\log x \cdot \frac{1}{n}} \]
      3. distribute-rgt-out--76.8%

        \[\leadsto \color{blue}{\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)} \]
    8. Applied egg-rr76.8%

      \[\leadsto \color{blue}{\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)} \]

    if -9.99999999999999978e-138 < (/.f64 1 n) < -1.9999999999999999e-154

    1. Initial program 22.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 39.7%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def39.7%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified39.7%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 85.8%

      \[\leadsto \frac{\color{blue}{\left(0.3333333333333333 \cdot \frac{1}{{x}^{3}} + \frac{1}{x}\right) - 0.5 \cdot \frac{1}{{x}^{2}}}}{n} \]
    6. Step-by-step derivation
      1. associate--l+85.8%

        \[\leadsto \frac{\color{blue}{0.3333333333333333 \cdot \frac{1}{{x}^{3}} + \left(\frac{1}{x} - 0.5 \cdot \frac{1}{{x}^{2}}\right)}}{n} \]
      2. associate-*r/85.8%

        \[\leadsto \frac{\color{blue}{\frac{0.3333333333333333 \cdot 1}{{x}^{3}}} + \left(\frac{1}{x} - 0.5 \cdot \frac{1}{{x}^{2}}\right)}{n} \]
      3. metadata-eval85.8%

        \[\leadsto \frac{\frac{\color{blue}{0.3333333333333333}}{{x}^{3}} + \left(\frac{1}{x} - 0.5 \cdot \frac{1}{{x}^{2}}\right)}{n} \]
      4. associate-*r/85.8%

        \[\leadsto \frac{\frac{0.3333333333333333}{{x}^{3}} + \left(\frac{1}{x} - \color{blue}{\frac{0.5 \cdot 1}{{x}^{2}}}\right)}{n} \]
      5. metadata-eval85.8%

        \[\leadsto \frac{\frac{0.3333333333333333}{{x}^{3}} + \left(\frac{1}{x} - \frac{\color{blue}{0.5}}{{x}^{2}}\right)}{n} \]
    7. Simplified85.8%

      \[\leadsto \frac{\color{blue}{\frac{0.3333333333333333}{{x}^{3}} + \left(\frac{1}{x} - \frac{0.5}{{x}^{2}}\right)}}{n} \]

    if -1.9999999999999999e-154 < (/.f64 1 n) < 2.00000000000000001e-150

    1. Initial program 40.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 96.5%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def96.5%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified96.5%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]

    if 2.00000000000000001e-150 < (/.f64 1 n) < 1e5

    1. Initial program 18.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 76.7%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg76.7%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac76.7%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg76.7%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg76.7%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative76.7%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified76.7%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. *-un-lft-identity76.7%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{\frac{\log x}{n}}}}{x \cdot n} \]
      2. times-frac76.7%

        \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{e^{\frac{\log x}{n}}}{n}} \]
      3. div-inv76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{e^{\color{blue}{\log x \cdot \frac{1}{n}}}}{n} \]
      4. exp-to-pow76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{\color{blue}{{x}^{\left(\frac{1}{n}\right)}}}{n} \]
    6. Applied egg-rr76.7%

      \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}} \]
    7. Step-by-step derivation
      1. associate-*l/76.9%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]
      2. *-un-lft-identity76.9%

        \[\leadsto \frac{\color{blue}{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}}{x} \]
    8. Applied egg-rr76.9%

      \[\leadsto \color{blue}{\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]

    if 1e5 < (/.f64 1 n)

    1. Initial program 60.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around 0 60.0%

      \[\leadsto \color{blue}{e^{\frac{\log \left(1 + x\right)}{n}}} - {x}^{\left(\frac{1}{n}\right)} \]
    3. Step-by-step derivation
      1. log1p-def100.0%

        \[\leadsto e^{\frac{\color{blue}{\mathsf{log1p}\left(x\right)}}{n}} - {x}^{\left(\frac{1}{n}\right)} \]
    4. Simplified100.0%

      \[\leadsto \color{blue}{e^{\frac{\mathsf{log1p}\left(x\right)}{n}}} - {x}^{\left(\frac{1}{n}\right)} \]
    5. Taylor expanded in x around 0 100.0%

      \[\leadsto e^{\color{blue}{\frac{x}{n}}} - {x}^{\left(\frac{1}{n}\right)} \]
  3. Recombined 6 regimes into one program.
  4. Final simplification92.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;{x}^{\left(\frac{1}{n}\right)} \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\frac{0.3333333333333333}{{x}^{3}} + \left(\frac{1}{x} - \frac{0.5}{{x}^{2}}\right)}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;\frac{\mathsf{log1p}\left(x\right) - \log x}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}\\ \mathbf{else}:\\ \;\;\;\;e^{\frac{x}{n}} - {x}^{\left(\frac{1}{n}\right)}\\ \end{array} \]

Alternative 4: 80.3% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\mathsf{log1p}\left(x\right) - \log x}{n}\\ t_1 := {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\frac{1}{x} - \frac{0.5}{{x}^{2}}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{t_1}{n}}{x}\\ \mathbf{elif}\;\frac{1}{n} \leq 10^{+204}:\\ \;\;\;\;\left(1 + \frac{x}{n}\right) - t_1\\ \mathbf{else}:\\ \;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (let* ((t_0 (/ (- (log1p x) (log x)) n)) (t_1 (pow x (/ 1.0 n))))
   (if (<= (/ 1.0 n) -5e-19)
     (* t_1 (/ (/ 1.0 x) n))
     (if (<= (/ 1.0 n) -1e-137)
       t_0
       (if (<= (/ 1.0 n) -2e-154)
         (/ (- (/ 1.0 x) (/ 0.5 (pow x 2.0))) n)
         (if (<= (/ 1.0 n) 2e-150)
           t_0
           (if (<= (/ 1.0 n) 100000.0)
             (/ (/ t_1 n) x)
             (if (<= (/ 1.0 n) 1e+204)
               (- (+ 1.0 (/ x n)) t_1)
               (/ 0.3333333333333333 (* n (pow x 3.0)))))))))))
double code(double x, double n) {
	double t_0 = (log1p(x) - log(x)) / n;
	double t_1 = pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = ((1.0 / x) - (0.5 / pow(x, 2.0))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else if ((1.0 / n) <= 1e+204) {
		tmp = (1.0 + (x / n)) - t_1;
	} else {
		tmp = 0.3333333333333333 / (n * pow(x, 3.0));
	}
	return tmp;
}
public static double code(double x, double n) {
	double t_0 = (Math.log1p(x) - Math.log(x)) / n;
	double t_1 = Math.pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = ((1.0 / x) - (0.5 / Math.pow(x, 2.0))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else if ((1.0 / n) <= 1e+204) {
		tmp = (1.0 + (x / n)) - t_1;
	} else {
		tmp = 0.3333333333333333 / (n * Math.pow(x, 3.0));
	}
	return tmp;
}
def code(x, n):
	t_0 = (math.log1p(x) - math.log(x)) / n
	t_1 = math.pow(x, (1.0 / n))
	tmp = 0
	if (1.0 / n) <= -5e-19:
		tmp = t_1 * ((1.0 / x) / n)
	elif (1.0 / n) <= -1e-137:
		tmp = t_0
	elif (1.0 / n) <= -2e-154:
		tmp = ((1.0 / x) - (0.5 / math.pow(x, 2.0))) / n
	elif (1.0 / n) <= 2e-150:
		tmp = t_0
	elif (1.0 / n) <= 100000.0:
		tmp = (t_1 / n) / x
	elif (1.0 / n) <= 1e+204:
		tmp = (1.0 + (x / n)) - t_1
	else:
		tmp = 0.3333333333333333 / (n * math.pow(x, 3.0))
	return tmp
function code(x, n)
	t_0 = Float64(Float64(log1p(x) - log(x)) / n)
	t_1 = x ^ Float64(1.0 / n)
	tmp = 0.0
	if (Float64(1.0 / n) <= -5e-19)
		tmp = Float64(t_1 * Float64(Float64(1.0 / x) / n));
	elseif (Float64(1.0 / n) <= -1e-137)
		tmp = t_0;
	elseif (Float64(1.0 / n) <= -2e-154)
		tmp = Float64(Float64(Float64(1.0 / x) - Float64(0.5 / (x ^ 2.0))) / n);
	elseif (Float64(1.0 / n) <= 2e-150)
		tmp = t_0;
	elseif (Float64(1.0 / n) <= 100000.0)
		tmp = Float64(Float64(t_1 / n) / x);
	elseif (Float64(1.0 / n) <= 1e+204)
		tmp = Float64(Float64(1.0 + Float64(x / n)) - t_1);
	else
		tmp = Float64(0.3333333333333333 / Float64(n * (x ^ 3.0)));
	end
	return tmp
end
code[x_, n_] := Block[{t$95$0 = N[(N[(N[Log[1 + x], $MachinePrecision] - N[Log[x], $MachinePrecision]), $MachinePrecision] / n), $MachinePrecision]}, Block[{t$95$1 = N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[N[(1.0 / n), $MachinePrecision], -5e-19], N[(t$95$1 * N[(N[(1.0 / x), $MachinePrecision] / n), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], -1e-137], t$95$0, If[LessEqual[N[(1.0 / n), $MachinePrecision], -2e-154], N[(N[(N[(1.0 / x), $MachinePrecision] - N[(0.5 / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / n), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 2e-150], t$95$0, If[LessEqual[N[(1.0 / n), $MachinePrecision], 100000.0], N[(N[(t$95$1 / n), $MachinePrecision] / x), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 1e+204], N[(N[(1.0 + N[(x / n), $MachinePrecision]), $MachinePrecision] - t$95$1), $MachinePrecision], N[(0.3333333333333333 / N[(n * N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\mathsf{log1p}\left(x\right) - \log x}{n}\\
t_1 := {x}^{\left(\frac{1}{n}\right)}\\
\mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\
\;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\
\;\;\;\;\frac{\frac{1}{x} - \frac{0.5}{{x}^{2}}}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;\frac{1}{n} \leq 100000:\\
\;\;\;\;\frac{\frac{t_1}{n}}{x}\\

\mathbf{elif}\;\frac{1}{n} \leq 10^{+204}:\\
\;\;\;\;\left(1 + \frac{x}{n}\right) - t_1\\

\mathbf{else}:\\
\;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 6 regimes
  2. if (/.f64 1 n) < -5.0000000000000004e-19

    1. Initial program 97.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 98.8%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg98.8%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac98.8%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg98.8%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg98.8%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative98.8%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified98.8%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. div-inv98.8%

        \[\leadsto \color{blue}{e^{\frac{\log x}{n}} \cdot \frac{1}{x \cdot n}} \]
      2. associate-/r*98.8%

        \[\leadsto e^{\frac{\log x}{n}} \cdot \color{blue}{\frac{\frac{1}{x}}{n}} \]
      3. div-inv98.8%

        \[\leadsto e^{\color{blue}{\log x \cdot \frac{1}{n}}} \cdot \frac{\frac{1}{x}}{n} \]
      4. exp-to-pow98.8%

        \[\leadsto \color{blue}{{x}^{\left(\frac{1}{n}\right)}} \cdot \frac{\frac{1}{x}}{n} \]
    6. Applied egg-rr98.8%

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

    if -5.0000000000000004e-19 < (/.f64 1 n) < -9.99999999999999978e-138 or -1.9999999999999999e-154 < (/.f64 1 n) < 2.00000000000000001e-150

    1. Initial program 33.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 91.1%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def91.1%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified91.1%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]

    if -9.99999999999999978e-138 < (/.f64 1 n) < -1.9999999999999999e-154

    1. Initial program 22.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 39.7%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def39.7%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified39.7%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 84.4%

      \[\leadsto \frac{\color{blue}{\frac{1}{x} - 0.5 \cdot \frac{1}{{x}^{2}}}}{n} \]
    6. Step-by-step derivation
      1. associate-*r/84.4%

        \[\leadsto \frac{\frac{1}{x} - \color{blue}{\frac{0.5 \cdot 1}{{x}^{2}}}}{n} \]
      2. metadata-eval84.4%

        \[\leadsto \frac{\frac{1}{x} - \frac{\color{blue}{0.5}}{{x}^{2}}}{n} \]
    7. Simplified84.4%

      \[\leadsto \frac{\color{blue}{\frac{1}{x} - \frac{0.5}{{x}^{2}}}}{n} \]

    if 2.00000000000000001e-150 < (/.f64 1 n) < 1e5

    1. Initial program 18.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 76.7%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg76.7%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac76.7%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg76.7%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg76.7%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative76.7%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified76.7%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. *-un-lft-identity76.7%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{\frac{\log x}{n}}}}{x \cdot n} \]
      2. times-frac76.7%

        \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{e^{\frac{\log x}{n}}}{n}} \]
      3. div-inv76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{e^{\color{blue}{\log x \cdot \frac{1}{n}}}}{n} \]
      4. exp-to-pow76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{\color{blue}{{x}^{\left(\frac{1}{n}\right)}}}{n} \]
    6. Applied egg-rr76.7%

      \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}} \]
    7. Step-by-step derivation
      1. associate-*l/76.9%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]
      2. *-un-lft-identity76.9%

        \[\leadsto \frac{\color{blue}{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}}{x} \]
    8. Applied egg-rr76.9%

      \[\leadsto \color{blue}{\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]

    if 1e5 < (/.f64 1 n) < 9.99999999999999989e203

    1. Initial program 84.4%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around 0 86.3%

      \[\leadsto \color{blue}{\left(1 + \frac{x}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]

    if 9.99999999999999989e203 < (/.f64 1 n)

    1. Initial program 3.1%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 7.4%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def7.4%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified7.4%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 11.1%

      \[\leadsto \color{blue}{\left(0.3333333333333333 \cdot \frac{1}{n \cdot {x}^{3}} + \frac{1}{n \cdot x}\right) - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}} \]
    6. Step-by-step derivation
      1. associate--l+11.1%

        \[\leadsto \color{blue}{0.3333333333333333 \cdot \frac{1}{n \cdot {x}^{3}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right)} \]
      2. associate-*r/11.1%

        \[\leadsto \color{blue}{\frac{0.3333333333333333 \cdot 1}{n \cdot {x}^{3}}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      3. metadata-eval11.1%

        \[\leadsto \frac{\color{blue}{0.3333333333333333}}{n \cdot {x}^{3}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      4. *-commutative11.1%

        \[\leadsto \frac{0.3333333333333333}{\color{blue}{{x}^{3} \cdot n}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      5. *-commutative11.1%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{\color{blue}{x \cdot n}} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      6. associate-*r/11.1%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \color{blue}{\frac{0.5 \cdot 1}{n \cdot {x}^{2}}}\right) \]
      7. metadata-eval11.1%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{\color{blue}{0.5}}{n \cdot {x}^{2}}\right) \]
      8. *-commutative11.1%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{0.5}{\color{blue}{{x}^{2} \cdot n}}\right) \]
    7. Simplified11.1%

      \[\leadsto \color{blue}{\frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{0.5}{{x}^{2} \cdot n}\right)} \]
    8. Taylor expanded in x around 0 100.0%

      \[\leadsto \color{blue}{\frac{0.3333333333333333}{n \cdot {x}^{3}}} \]
  3. Recombined 6 regimes into one program.
  4. Final simplification91.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;{x}^{\left(\frac{1}{n}\right)} \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;\frac{\mathsf{log1p}\left(x\right) - \log x}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\frac{1}{x} - \frac{0.5}{{x}^{2}}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;\frac{\mathsf{log1p}\left(x\right) - \log x}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}\\ \mathbf{elif}\;\frac{1}{n} \leq 10^{+204}:\\ \;\;\;\;\left(1 + \frac{x}{n}\right) - {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\ \end{array} \]

Alternative 5: 80.2% accurate, 0.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \mathsf{log1p}\left(x\right) - \log x\\ t_1 := {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;\frac{1}{n} \cdot t_0\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\frac{1}{x} - \frac{0.5}{{x}^{2}}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;\frac{t_0}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{t_1}{n}}{x}\\ \mathbf{elif}\;\frac{1}{n} \leq 10^{+204}:\\ \;\;\;\;\left(1 + \frac{x}{n}\right) - t_1\\ \mathbf{else}:\\ \;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (let* ((t_0 (- (log1p x) (log x))) (t_1 (pow x (/ 1.0 n))))
   (if (<= (/ 1.0 n) -5e-19)
     (* t_1 (/ (/ 1.0 x) n))
     (if (<= (/ 1.0 n) -1e-137)
       (* (/ 1.0 n) t_0)
       (if (<= (/ 1.0 n) -2e-154)
         (/ (- (/ 1.0 x) (/ 0.5 (pow x 2.0))) n)
         (if (<= (/ 1.0 n) 2e-150)
           (/ t_0 n)
           (if (<= (/ 1.0 n) 100000.0)
             (/ (/ t_1 n) x)
             (if (<= (/ 1.0 n) 1e+204)
               (- (+ 1.0 (/ x n)) t_1)
               (/ 0.3333333333333333 (* n (pow x 3.0)))))))))))
double code(double x, double n) {
	double t_0 = log1p(x) - log(x);
	double t_1 = pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = (1.0 / n) * t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = ((1.0 / x) - (0.5 / pow(x, 2.0))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0 / n;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else if ((1.0 / n) <= 1e+204) {
		tmp = (1.0 + (x / n)) - t_1;
	} else {
		tmp = 0.3333333333333333 / (n * pow(x, 3.0));
	}
	return tmp;
}
public static double code(double x, double n) {
	double t_0 = Math.log1p(x) - Math.log(x);
	double t_1 = Math.pow(x, (1.0 / n));
	double tmp;
	if ((1.0 / n) <= -5e-19) {
		tmp = t_1 * ((1.0 / x) / n);
	} else if ((1.0 / n) <= -1e-137) {
		tmp = (1.0 / n) * t_0;
	} else if ((1.0 / n) <= -2e-154) {
		tmp = ((1.0 / x) - (0.5 / Math.pow(x, 2.0))) / n;
	} else if ((1.0 / n) <= 2e-150) {
		tmp = t_0 / n;
	} else if ((1.0 / n) <= 100000.0) {
		tmp = (t_1 / n) / x;
	} else if ((1.0 / n) <= 1e+204) {
		tmp = (1.0 + (x / n)) - t_1;
	} else {
		tmp = 0.3333333333333333 / (n * Math.pow(x, 3.0));
	}
	return tmp;
}
def code(x, n):
	t_0 = math.log1p(x) - math.log(x)
	t_1 = math.pow(x, (1.0 / n))
	tmp = 0
	if (1.0 / n) <= -5e-19:
		tmp = t_1 * ((1.0 / x) / n)
	elif (1.0 / n) <= -1e-137:
		tmp = (1.0 / n) * t_0
	elif (1.0 / n) <= -2e-154:
		tmp = ((1.0 / x) - (0.5 / math.pow(x, 2.0))) / n
	elif (1.0 / n) <= 2e-150:
		tmp = t_0 / n
	elif (1.0 / n) <= 100000.0:
		tmp = (t_1 / n) / x
	elif (1.0 / n) <= 1e+204:
		tmp = (1.0 + (x / n)) - t_1
	else:
		tmp = 0.3333333333333333 / (n * math.pow(x, 3.0))
	return tmp
function code(x, n)
	t_0 = Float64(log1p(x) - log(x))
	t_1 = x ^ Float64(1.0 / n)
	tmp = 0.0
	if (Float64(1.0 / n) <= -5e-19)
		tmp = Float64(t_1 * Float64(Float64(1.0 / x) / n));
	elseif (Float64(1.0 / n) <= -1e-137)
		tmp = Float64(Float64(1.0 / n) * t_0);
	elseif (Float64(1.0 / n) <= -2e-154)
		tmp = Float64(Float64(Float64(1.0 / x) - Float64(0.5 / (x ^ 2.0))) / n);
	elseif (Float64(1.0 / n) <= 2e-150)
		tmp = Float64(t_0 / n);
	elseif (Float64(1.0 / n) <= 100000.0)
		tmp = Float64(Float64(t_1 / n) / x);
	elseif (Float64(1.0 / n) <= 1e+204)
		tmp = Float64(Float64(1.0 + Float64(x / n)) - t_1);
	else
		tmp = Float64(0.3333333333333333 / Float64(n * (x ^ 3.0)));
	end
	return tmp
end
code[x_, n_] := Block[{t$95$0 = N[(N[Log[1 + x], $MachinePrecision] - N[Log[x], $MachinePrecision]), $MachinePrecision]}, Block[{t$95$1 = N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision]}, If[LessEqual[N[(1.0 / n), $MachinePrecision], -5e-19], N[(t$95$1 * N[(N[(1.0 / x), $MachinePrecision] / n), $MachinePrecision]), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], -1e-137], N[(N[(1.0 / n), $MachinePrecision] * t$95$0), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], -2e-154], N[(N[(N[(1.0 / x), $MachinePrecision] - N[(0.5 / N[Power[x, 2.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / n), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 2e-150], N[(t$95$0 / n), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 100000.0], N[(N[(t$95$1 / n), $MachinePrecision] / x), $MachinePrecision], If[LessEqual[N[(1.0 / n), $MachinePrecision], 1e+204], N[(N[(1.0 + N[(x / n), $MachinePrecision]), $MachinePrecision] - t$95$1), $MachinePrecision], N[(0.3333333333333333 / N[(n * N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \mathsf{log1p}\left(x\right) - \log x\\
t_1 := {x}^{\left(\frac{1}{n}\right)}\\
\mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\
\;\;\;\;t_1 \cdot \frac{\frac{1}{x}}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\
\;\;\;\;\frac{1}{n} \cdot t_0\\

\mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\
\;\;\;\;\frac{\frac{1}{x} - \frac{0.5}{{x}^{2}}}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\
\;\;\;\;\frac{t_0}{n}\\

\mathbf{elif}\;\frac{1}{n} \leq 100000:\\
\;\;\;\;\frac{\frac{t_1}{n}}{x}\\

\mathbf{elif}\;\frac{1}{n} \leq 10^{+204}:\\
\;\;\;\;\left(1 + \frac{x}{n}\right) - t_1\\

\mathbf{else}:\\
\;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\


\end{array}
\end{array}
Derivation
  1. Split input into 7 regimes
  2. if (/.f64 1 n) < -5.0000000000000004e-19

    1. Initial program 97.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 98.8%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg98.8%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg98.8%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac98.8%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg98.8%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg98.8%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative98.8%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified98.8%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. div-inv98.8%

        \[\leadsto \color{blue}{e^{\frac{\log x}{n}} \cdot \frac{1}{x \cdot n}} \]
      2. associate-/r*98.8%

        \[\leadsto e^{\frac{\log x}{n}} \cdot \color{blue}{\frac{\frac{1}{x}}{n}} \]
      3. div-inv98.8%

        \[\leadsto e^{\color{blue}{\log x \cdot \frac{1}{n}}} \cdot \frac{\frac{1}{x}}{n} \]
      4. exp-to-pow98.8%

        \[\leadsto \color{blue}{{x}^{\left(\frac{1}{n}\right)}} \cdot \frac{\frac{1}{x}}{n} \]
    6. Applied egg-rr98.8%

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

    if -5.0000000000000004e-19 < (/.f64 1 n) < -9.99999999999999978e-138

    1. Initial program 14.1%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 76.8%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def76.8%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified76.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Step-by-step derivation
      1. div-sub76.8%

        \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} - \frac{\log x}{n}} \]
    6. Applied egg-rr76.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} - \frac{\log x}{n}} \]
    7. Step-by-step derivation
      1. div-inv73.9%

        \[\leadsto \color{blue}{\mathsf{log1p}\left(x\right) \cdot \frac{1}{n}} - \frac{\log x}{n} \]
      2. div-inv76.8%

        \[\leadsto \mathsf{log1p}\left(x\right) \cdot \frac{1}{n} - \color{blue}{\log x \cdot \frac{1}{n}} \]
      3. distribute-rgt-out--76.8%

        \[\leadsto \color{blue}{\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)} \]
    8. Applied egg-rr76.8%

      \[\leadsto \color{blue}{\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)} \]

    if -9.99999999999999978e-138 < (/.f64 1 n) < -1.9999999999999999e-154

    1. Initial program 22.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 39.7%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def39.7%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified39.7%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 84.4%

      \[\leadsto \frac{\color{blue}{\frac{1}{x} - 0.5 \cdot \frac{1}{{x}^{2}}}}{n} \]
    6. Step-by-step derivation
      1. associate-*r/84.4%

        \[\leadsto \frac{\frac{1}{x} - \color{blue}{\frac{0.5 \cdot 1}{{x}^{2}}}}{n} \]
      2. metadata-eval84.4%

        \[\leadsto \frac{\frac{1}{x} - \frac{\color{blue}{0.5}}{{x}^{2}}}{n} \]
    7. Simplified84.4%

      \[\leadsto \frac{\color{blue}{\frac{1}{x} - \frac{0.5}{{x}^{2}}}}{n} \]

    if -1.9999999999999999e-154 < (/.f64 1 n) < 2.00000000000000001e-150

    1. Initial program 40.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 96.5%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def96.5%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified96.5%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]

    if 2.00000000000000001e-150 < (/.f64 1 n) < 1e5

    1. Initial program 18.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 76.7%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg76.7%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg76.7%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac76.7%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg76.7%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg76.7%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative76.7%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified76.7%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. *-un-lft-identity76.7%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{\frac{\log x}{n}}}}{x \cdot n} \]
      2. times-frac76.7%

        \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{e^{\frac{\log x}{n}}}{n}} \]
      3. div-inv76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{e^{\color{blue}{\log x \cdot \frac{1}{n}}}}{n} \]
      4. exp-to-pow76.7%

        \[\leadsto \frac{1}{x} \cdot \frac{\color{blue}{{x}^{\left(\frac{1}{n}\right)}}}{n} \]
    6. Applied egg-rr76.7%

      \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}} \]
    7. Step-by-step derivation
      1. associate-*l/76.9%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]
      2. *-un-lft-identity76.9%

        \[\leadsto \frac{\color{blue}{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}}{x} \]
    8. Applied egg-rr76.9%

      \[\leadsto \color{blue}{\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]

    if 1e5 < (/.f64 1 n) < 9.99999999999999989e203

    1. Initial program 84.4%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around 0 86.3%

      \[\leadsto \color{blue}{\left(1 + \frac{x}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]

    if 9.99999999999999989e203 < (/.f64 1 n)

    1. Initial program 3.1%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 7.4%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def7.4%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified7.4%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 11.1%

      \[\leadsto \color{blue}{\left(0.3333333333333333 \cdot \frac{1}{n \cdot {x}^{3}} + \frac{1}{n \cdot x}\right) - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}} \]
    6. Step-by-step derivation
      1. associate--l+11.1%

        \[\leadsto \color{blue}{0.3333333333333333 \cdot \frac{1}{n \cdot {x}^{3}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right)} \]
      2. associate-*r/11.1%

        \[\leadsto \color{blue}{\frac{0.3333333333333333 \cdot 1}{n \cdot {x}^{3}}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      3. metadata-eval11.1%

        \[\leadsto \frac{\color{blue}{0.3333333333333333}}{n \cdot {x}^{3}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      4. *-commutative11.1%

        \[\leadsto \frac{0.3333333333333333}{\color{blue}{{x}^{3} \cdot n}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      5. *-commutative11.1%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{\color{blue}{x \cdot n}} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      6. associate-*r/11.1%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \color{blue}{\frac{0.5 \cdot 1}{n \cdot {x}^{2}}}\right) \]
      7. metadata-eval11.1%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{\color{blue}{0.5}}{n \cdot {x}^{2}}\right) \]
      8. *-commutative11.1%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{0.5}{\color{blue}{{x}^{2} \cdot n}}\right) \]
    7. Simplified11.1%

      \[\leadsto \color{blue}{\frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{0.5}{{x}^{2} \cdot n}\right)} \]
    8. Taylor expanded in x around 0 100.0%

      \[\leadsto \color{blue}{\frac{0.3333333333333333}{n \cdot {x}^{3}}} \]
  3. Recombined 7 regimes into one program.
  4. Final simplification91.6%

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{1}{n} \leq -5 \cdot 10^{-19}:\\ \;\;\;\;{x}^{\left(\frac{1}{n}\right)} \cdot \frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq -1 \cdot 10^{-137}:\\ \;\;\;\;\frac{1}{n} \cdot \left(\mathsf{log1p}\left(x\right) - \log x\right)\\ \mathbf{elif}\;\frac{1}{n} \leq -2 \cdot 10^{-154}:\\ \;\;\;\;\frac{\frac{1}{x} - \frac{0.5}{{x}^{2}}}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 2 \cdot 10^{-150}:\\ \;\;\;\;\frac{\mathsf{log1p}\left(x\right) - \log x}{n}\\ \mathbf{elif}\;\frac{1}{n} \leq 100000:\\ \;\;\;\;\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}\\ \mathbf{elif}\;\frac{1}{n} \leq 10^{+204}:\\ \;\;\;\;\left(1 + \frac{x}{n}\right) - {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{else}:\\ \;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\ \end{array} \]

Alternative 6: 60.2% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\frac{1}{x}}{n}\\ t_1 := \frac{-\log x}{n}\\ \mathbf{if}\;n \leq -5.8 \cdot 10^{+139}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;n \leq -18:\\ \;\;\;\;t_1\\ \mathbf{elif}\;n \leq 1.2 \cdot 10^{-204}:\\ \;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\ \mathbf{elif}\;n \leq 6800000000:\\ \;\;\;\;1 - {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{elif}\;n \leq 4.6 \cdot 10^{+149}:\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;t_1\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (let* ((t_0 (/ (/ 1.0 x) n)) (t_1 (/ (- (log x)) n)))
   (if (<= n -5.8e+139)
     t_0
     (if (<= n -18.0)
       t_1
       (if (<= n 1.2e-204)
         (/ 0.3333333333333333 (* n (pow x 3.0)))
         (if (<= n 6800000000.0)
           (- 1.0 (pow x (/ 1.0 n)))
           (if (<= n 4.6e+149) t_0 t_1)))))))
double code(double x, double n) {
	double t_0 = (1.0 / x) / n;
	double t_1 = -log(x) / n;
	double tmp;
	if (n <= -5.8e+139) {
		tmp = t_0;
	} else if (n <= -18.0) {
		tmp = t_1;
	} else if (n <= 1.2e-204) {
		tmp = 0.3333333333333333 / (n * pow(x, 3.0));
	} else if (n <= 6800000000.0) {
		tmp = 1.0 - pow(x, (1.0 / n));
	} else if (n <= 4.6e+149) {
		tmp = t_0;
	} else {
		tmp = t_1;
	}
	return tmp;
}
real(8) function code(x, n)
    real(8), intent (in) :: x
    real(8), intent (in) :: n
    real(8) :: t_0
    real(8) :: t_1
    real(8) :: tmp
    t_0 = (1.0d0 / x) / n
    t_1 = -log(x) / n
    if (n <= (-5.8d+139)) then
        tmp = t_0
    else if (n <= (-18.0d0)) then
        tmp = t_1
    else if (n <= 1.2d-204) then
        tmp = 0.3333333333333333d0 / (n * (x ** 3.0d0))
    else if (n <= 6800000000.0d0) then
        tmp = 1.0d0 - (x ** (1.0d0 / n))
    else if (n <= 4.6d+149) then
        tmp = t_0
    else
        tmp = t_1
    end if
    code = tmp
end function
public static double code(double x, double n) {
	double t_0 = (1.0 / x) / n;
	double t_1 = -Math.log(x) / n;
	double tmp;
	if (n <= -5.8e+139) {
		tmp = t_0;
	} else if (n <= -18.0) {
		tmp = t_1;
	} else if (n <= 1.2e-204) {
		tmp = 0.3333333333333333 / (n * Math.pow(x, 3.0));
	} else if (n <= 6800000000.0) {
		tmp = 1.0 - Math.pow(x, (1.0 / n));
	} else if (n <= 4.6e+149) {
		tmp = t_0;
	} else {
		tmp = t_1;
	}
	return tmp;
}
def code(x, n):
	t_0 = (1.0 / x) / n
	t_1 = -math.log(x) / n
	tmp = 0
	if n <= -5.8e+139:
		tmp = t_0
	elif n <= -18.0:
		tmp = t_1
	elif n <= 1.2e-204:
		tmp = 0.3333333333333333 / (n * math.pow(x, 3.0))
	elif n <= 6800000000.0:
		tmp = 1.0 - math.pow(x, (1.0 / n))
	elif n <= 4.6e+149:
		tmp = t_0
	else:
		tmp = t_1
	return tmp
function code(x, n)
	t_0 = Float64(Float64(1.0 / x) / n)
	t_1 = Float64(Float64(-log(x)) / n)
	tmp = 0.0
	if (n <= -5.8e+139)
		tmp = t_0;
	elseif (n <= -18.0)
		tmp = t_1;
	elseif (n <= 1.2e-204)
		tmp = Float64(0.3333333333333333 / Float64(n * (x ^ 3.0)));
	elseif (n <= 6800000000.0)
		tmp = Float64(1.0 - (x ^ Float64(1.0 / n)));
	elseif (n <= 4.6e+149)
		tmp = t_0;
	else
		tmp = t_1;
	end
	return tmp
end
function tmp_2 = code(x, n)
	t_0 = (1.0 / x) / n;
	t_1 = -log(x) / n;
	tmp = 0.0;
	if (n <= -5.8e+139)
		tmp = t_0;
	elseif (n <= -18.0)
		tmp = t_1;
	elseif (n <= 1.2e-204)
		tmp = 0.3333333333333333 / (n * (x ^ 3.0));
	elseif (n <= 6800000000.0)
		tmp = 1.0 - (x ^ (1.0 / n));
	elseif (n <= 4.6e+149)
		tmp = t_0;
	else
		tmp = t_1;
	end
	tmp_2 = tmp;
end
code[x_, n_] := Block[{t$95$0 = N[(N[(1.0 / x), $MachinePrecision] / n), $MachinePrecision]}, Block[{t$95$1 = N[((-N[Log[x], $MachinePrecision]) / n), $MachinePrecision]}, If[LessEqual[n, -5.8e+139], t$95$0, If[LessEqual[n, -18.0], t$95$1, If[LessEqual[n, 1.2e-204], N[(0.3333333333333333 / N[(n * N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[n, 6800000000.0], N[(1.0 - N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[n, 4.6e+149], t$95$0, t$95$1]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\frac{1}{x}}{n}\\
t_1 := \frac{-\log x}{n}\\
\mathbf{if}\;n \leq -5.8 \cdot 10^{+139}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;n \leq -18:\\
\;\;\;\;t_1\\

\mathbf{elif}\;n \leq 1.2 \cdot 10^{-204}:\\
\;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\

\mathbf{elif}\;n \leq 6800000000:\\
\;\;\;\;1 - {x}^{\left(\frac{1}{n}\right)}\\

\mathbf{elif}\;n \leq 4.6 \cdot 10^{+149}:\\
\;\;\;\;t_0\\

\mathbf{else}:\\
\;\;\;\;t_1\\


\end{array}
\end{array}
Derivation
  1. Split input into 4 regimes
  2. if n < -5.7999999999999998e139 or 6.8e9 < n < 4.5999999999999997e149

    1. Initial program 33.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 68.9%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def68.9%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified68.9%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 63.3%

      \[\leadsto \frac{\color{blue}{\frac{1}{x}}}{n} \]

    if -5.7999999999999998e139 < n < -18 or 4.5999999999999997e149 < n

    1. Initial program 24.6%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 84.0%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def84.0%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified84.0%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around 0 63.7%

      \[\leadsto \frac{\color{blue}{-1 \cdot \log x}}{n} \]
    6. Step-by-step derivation
      1. mul-1-neg63.7%

        \[\leadsto \frac{\color{blue}{-\log x}}{n} \]
    7. Simplified63.7%

      \[\leadsto \frac{\color{blue}{-\log x}}{n} \]

    if -18 < n < 1.2e-204

    1. Initial program 89.9%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 48.6%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def48.6%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified48.6%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 6.7%

      \[\leadsto \color{blue}{\left(0.3333333333333333 \cdot \frac{1}{n \cdot {x}^{3}} + \frac{1}{n \cdot x}\right) - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}} \]
    6. Step-by-step derivation
      1. associate--l+6.7%

        \[\leadsto \color{blue}{0.3333333333333333 \cdot \frac{1}{n \cdot {x}^{3}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right)} \]
      2. associate-*r/6.7%

        \[\leadsto \color{blue}{\frac{0.3333333333333333 \cdot 1}{n \cdot {x}^{3}}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      3. metadata-eval6.7%

        \[\leadsto \frac{\color{blue}{0.3333333333333333}}{n \cdot {x}^{3}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      4. *-commutative6.7%

        \[\leadsto \frac{0.3333333333333333}{\color{blue}{{x}^{3} \cdot n}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      5. *-commutative6.7%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{\color{blue}{x \cdot n}} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      6. associate-*r/6.7%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \color{blue}{\frac{0.5 \cdot 1}{n \cdot {x}^{2}}}\right) \]
      7. metadata-eval6.7%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{\color{blue}{0.5}}{n \cdot {x}^{2}}\right) \]
      8. *-commutative6.7%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{0.5}{\color{blue}{{x}^{2} \cdot n}}\right) \]
    7. Simplified6.7%

      \[\leadsto \color{blue}{\frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{0.5}{{x}^{2} \cdot n}\right)} \]
    8. Taylor expanded in x around 0 72.2%

      \[\leadsto \color{blue}{\frac{0.3333333333333333}{n \cdot {x}^{3}}} \]

    if 1.2e-204 < n < 6.8e9

    1. Initial program 76.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around 0 75.9%

      \[\leadsto \color{blue}{1} - {x}^{\left(\frac{1}{n}\right)} \]
  3. Recombined 4 regimes into one program.
  4. Final simplification67.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;n \leq -5.8 \cdot 10^{+139}:\\ \;\;\;\;\frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;n \leq -18:\\ \;\;\;\;\frac{-\log x}{n}\\ \mathbf{elif}\;n \leq 1.2 \cdot 10^{-204}:\\ \;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\ \mathbf{elif}\;n \leq 6800000000:\\ \;\;\;\;1 - {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{elif}\;n \leq 4.6 \cdot 10^{+149}:\\ \;\;\;\;\frac{\frac{1}{x}}{n}\\ \mathbf{else}:\\ \;\;\;\;\frac{-\log x}{n}\\ \end{array} \]

Alternative 7: 60.4% accurate, 1.6× speedup?

\[\begin{array}{l} \\ \begin{array}{l} t_0 := \frac{\frac{1}{x}}{n}\\ \mathbf{if}\;n \leq -1.02 \cdot 10^{+139}:\\ \;\;\;\;t_0\\ \mathbf{elif}\;n \leq -7.1:\\ \;\;\;\;\frac{x - \log x}{n}\\ \mathbf{elif}\;n \leq 1.35 \cdot 10^{-204}:\\ \;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\ \mathbf{elif}\;n \leq 1300000000:\\ \;\;\;\;1 - {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{elif}\;n \leq 6.8 \cdot 10^{+149}:\\ \;\;\;\;t_0\\ \mathbf{else}:\\ \;\;\;\;\frac{-\log x}{n}\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (let* ((t_0 (/ (/ 1.0 x) n)))
   (if (<= n -1.02e+139)
     t_0
     (if (<= n -7.1)
       (/ (- x (log x)) n)
       (if (<= n 1.35e-204)
         (/ 0.3333333333333333 (* n (pow x 3.0)))
         (if (<= n 1300000000.0)
           (- 1.0 (pow x (/ 1.0 n)))
           (if (<= n 6.8e+149) t_0 (/ (- (log x)) n))))))))
double code(double x, double n) {
	double t_0 = (1.0 / x) / n;
	double tmp;
	if (n <= -1.02e+139) {
		tmp = t_0;
	} else if (n <= -7.1) {
		tmp = (x - log(x)) / n;
	} else if (n <= 1.35e-204) {
		tmp = 0.3333333333333333 / (n * pow(x, 3.0));
	} else if (n <= 1300000000.0) {
		tmp = 1.0 - pow(x, (1.0 / n));
	} else if (n <= 6.8e+149) {
		tmp = t_0;
	} else {
		tmp = -log(x) / n;
	}
	return tmp;
}
real(8) function code(x, n)
    real(8), intent (in) :: x
    real(8), intent (in) :: n
    real(8) :: t_0
    real(8) :: tmp
    t_0 = (1.0d0 / x) / n
    if (n <= (-1.02d+139)) then
        tmp = t_0
    else if (n <= (-7.1d0)) then
        tmp = (x - log(x)) / n
    else if (n <= 1.35d-204) then
        tmp = 0.3333333333333333d0 / (n * (x ** 3.0d0))
    else if (n <= 1300000000.0d0) then
        tmp = 1.0d0 - (x ** (1.0d0 / n))
    else if (n <= 6.8d+149) then
        tmp = t_0
    else
        tmp = -log(x) / n
    end if
    code = tmp
end function
public static double code(double x, double n) {
	double t_0 = (1.0 / x) / n;
	double tmp;
	if (n <= -1.02e+139) {
		tmp = t_0;
	} else if (n <= -7.1) {
		tmp = (x - Math.log(x)) / n;
	} else if (n <= 1.35e-204) {
		tmp = 0.3333333333333333 / (n * Math.pow(x, 3.0));
	} else if (n <= 1300000000.0) {
		tmp = 1.0 - Math.pow(x, (1.0 / n));
	} else if (n <= 6.8e+149) {
		tmp = t_0;
	} else {
		tmp = -Math.log(x) / n;
	}
	return tmp;
}
def code(x, n):
	t_0 = (1.0 / x) / n
	tmp = 0
	if n <= -1.02e+139:
		tmp = t_0
	elif n <= -7.1:
		tmp = (x - math.log(x)) / n
	elif n <= 1.35e-204:
		tmp = 0.3333333333333333 / (n * math.pow(x, 3.0))
	elif n <= 1300000000.0:
		tmp = 1.0 - math.pow(x, (1.0 / n))
	elif n <= 6.8e+149:
		tmp = t_0
	else:
		tmp = -math.log(x) / n
	return tmp
function code(x, n)
	t_0 = Float64(Float64(1.0 / x) / n)
	tmp = 0.0
	if (n <= -1.02e+139)
		tmp = t_0;
	elseif (n <= -7.1)
		tmp = Float64(Float64(x - log(x)) / n);
	elseif (n <= 1.35e-204)
		tmp = Float64(0.3333333333333333 / Float64(n * (x ^ 3.0)));
	elseif (n <= 1300000000.0)
		tmp = Float64(1.0 - (x ^ Float64(1.0 / n)));
	elseif (n <= 6.8e+149)
		tmp = t_0;
	else
		tmp = Float64(Float64(-log(x)) / n);
	end
	return tmp
end
function tmp_2 = code(x, n)
	t_0 = (1.0 / x) / n;
	tmp = 0.0;
	if (n <= -1.02e+139)
		tmp = t_0;
	elseif (n <= -7.1)
		tmp = (x - log(x)) / n;
	elseif (n <= 1.35e-204)
		tmp = 0.3333333333333333 / (n * (x ^ 3.0));
	elseif (n <= 1300000000.0)
		tmp = 1.0 - (x ^ (1.0 / n));
	elseif (n <= 6.8e+149)
		tmp = t_0;
	else
		tmp = -log(x) / n;
	end
	tmp_2 = tmp;
end
code[x_, n_] := Block[{t$95$0 = N[(N[(1.0 / x), $MachinePrecision] / n), $MachinePrecision]}, If[LessEqual[n, -1.02e+139], t$95$0, If[LessEqual[n, -7.1], N[(N[(x - N[Log[x], $MachinePrecision]), $MachinePrecision] / n), $MachinePrecision], If[LessEqual[n, 1.35e-204], N[(0.3333333333333333 / N[(n * N[Power[x, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision], If[LessEqual[n, 1300000000.0], N[(1.0 - N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision]), $MachinePrecision], If[LessEqual[n, 6.8e+149], t$95$0, N[((-N[Log[x], $MachinePrecision]) / n), $MachinePrecision]]]]]]]
\begin{array}{l}

\\
\begin{array}{l}
t_0 := \frac{\frac{1}{x}}{n}\\
\mathbf{if}\;n \leq -1.02 \cdot 10^{+139}:\\
\;\;\;\;t_0\\

\mathbf{elif}\;n \leq -7.1:\\
\;\;\;\;\frac{x - \log x}{n}\\

\mathbf{elif}\;n \leq 1.35 \cdot 10^{-204}:\\
\;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\

\mathbf{elif}\;n \leq 1300000000:\\
\;\;\;\;1 - {x}^{\left(\frac{1}{n}\right)}\\

\mathbf{elif}\;n \leq 6.8 \cdot 10^{+149}:\\
\;\;\;\;t_0\\

\mathbf{else}:\\
\;\;\;\;\frac{-\log x}{n}\\


\end{array}
\end{array}
Derivation
  1. Split input into 5 regimes
  2. if n < -1.02e139 or 1.3e9 < n < 6.7999999999999997e149

    1. Initial program 33.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 68.9%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def68.9%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified68.9%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 63.3%

      \[\leadsto \frac{\color{blue}{\frac{1}{x}}}{n} \]

    if -1.02e139 < n < -7.0999999999999996

    1. Initial program 15.3%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 71.4%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def71.4%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified71.4%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around 0 62.2%

      \[\leadsto \frac{\color{blue}{x + -1 \cdot \log x}}{n} \]
    6. Step-by-step derivation
      1. mul-1-neg62.2%

        \[\leadsto \frac{x + \color{blue}{\left(-\log x\right)}}{n} \]
    7. Simplified62.2%

      \[\leadsto \frac{\color{blue}{x + \left(-\log x\right)}}{n} \]

    if -7.0999999999999996 < n < 1.34999999999999996e-204

    1. Initial program 89.9%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 48.6%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def48.6%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified48.6%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 6.7%

      \[\leadsto \color{blue}{\left(0.3333333333333333 \cdot \frac{1}{n \cdot {x}^{3}} + \frac{1}{n \cdot x}\right) - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}} \]
    6. Step-by-step derivation
      1. associate--l+6.7%

        \[\leadsto \color{blue}{0.3333333333333333 \cdot \frac{1}{n \cdot {x}^{3}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right)} \]
      2. associate-*r/6.7%

        \[\leadsto \color{blue}{\frac{0.3333333333333333 \cdot 1}{n \cdot {x}^{3}}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      3. metadata-eval6.7%

        \[\leadsto \frac{\color{blue}{0.3333333333333333}}{n \cdot {x}^{3}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      4. *-commutative6.7%

        \[\leadsto \frac{0.3333333333333333}{\color{blue}{{x}^{3} \cdot n}} + \left(\frac{1}{n \cdot x} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      5. *-commutative6.7%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{\color{blue}{x \cdot n}} - 0.5 \cdot \frac{1}{n \cdot {x}^{2}}\right) \]
      6. associate-*r/6.7%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \color{blue}{\frac{0.5 \cdot 1}{n \cdot {x}^{2}}}\right) \]
      7. metadata-eval6.7%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{\color{blue}{0.5}}{n \cdot {x}^{2}}\right) \]
      8. *-commutative6.7%

        \[\leadsto \frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{0.5}{\color{blue}{{x}^{2} \cdot n}}\right) \]
    7. Simplified6.7%

      \[\leadsto \color{blue}{\frac{0.3333333333333333}{{x}^{3} \cdot n} + \left(\frac{1}{x \cdot n} - \frac{0.5}{{x}^{2} \cdot n}\right)} \]
    8. Taylor expanded in x around 0 72.2%

      \[\leadsto \color{blue}{\frac{0.3333333333333333}{n \cdot {x}^{3}}} \]

    if 1.34999999999999996e-204 < n < 1.3e9

    1. Initial program 76.0%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around 0 75.9%

      \[\leadsto \color{blue}{1} - {x}^{\left(\frac{1}{n}\right)} \]

    if 6.7999999999999997e149 < n

    1. Initial program 32.1%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 94.1%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def94.1%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified94.1%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around 0 65.4%

      \[\leadsto \frac{\color{blue}{-1 \cdot \log x}}{n} \]
    6. Step-by-step derivation
      1. mul-1-neg65.4%

        \[\leadsto \frac{\color{blue}{-\log x}}{n} \]
    7. Simplified65.4%

      \[\leadsto \frac{\color{blue}{-\log x}}{n} \]
  3. Recombined 5 regimes into one program.
  4. Final simplification67.7%

    \[\leadsto \begin{array}{l} \mathbf{if}\;n \leq -1.02 \cdot 10^{+139}:\\ \;\;\;\;\frac{\frac{1}{x}}{n}\\ \mathbf{elif}\;n \leq -7.1:\\ \;\;\;\;\frac{x - \log x}{n}\\ \mathbf{elif}\;n \leq 1.35 \cdot 10^{-204}:\\ \;\;\;\;\frac{0.3333333333333333}{n \cdot {x}^{3}}\\ \mathbf{elif}\;n \leq 1300000000:\\ \;\;\;\;1 - {x}^{\left(\frac{1}{n}\right)}\\ \mathbf{elif}\;n \leq 6.8 \cdot 10^{+149}:\\ \;\;\;\;\frac{\frac{1}{x}}{n}\\ \mathbf{else}:\\ \;\;\;\;\frac{-\log x}{n}\\ \end{array} \]

Alternative 8: 60.1% accurate, 1.8× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.55:\\ \;\;\;\;\frac{-\log x}{n}\\ \mathbf{elif}\;x \leq 6.5 \cdot 10^{+185}:\\ \;\;\;\;\frac{\frac{1}{x}}{n}\\ \mathbf{else}:\\ \;\;\;\;\frac{\log x}{n} \cdot 0\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (if (<= x 0.55)
   (/ (- (log x)) n)
   (if (<= x 6.5e+185) (/ (/ 1.0 x) n) (* (/ (log x) n) 0.0))))
double code(double x, double n) {
	double tmp;
	if (x <= 0.55) {
		tmp = -log(x) / n;
	} else if (x <= 6.5e+185) {
		tmp = (1.0 / x) / n;
	} else {
		tmp = (log(x) / n) * 0.0;
	}
	return tmp;
}
real(8) function code(x, n)
    real(8), intent (in) :: x
    real(8), intent (in) :: n
    real(8) :: tmp
    if (x <= 0.55d0) then
        tmp = -log(x) / n
    else if (x <= 6.5d+185) then
        tmp = (1.0d0 / x) / n
    else
        tmp = (log(x) / n) * 0.0d0
    end if
    code = tmp
end function
public static double code(double x, double n) {
	double tmp;
	if (x <= 0.55) {
		tmp = -Math.log(x) / n;
	} else if (x <= 6.5e+185) {
		tmp = (1.0 / x) / n;
	} else {
		tmp = (Math.log(x) / n) * 0.0;
	}
	return tmp;
}
def code(x, n):
	tmp = 0
	if x <= 0.55:
		tmp = -math.log(x) / n
	elif x <= 6.5e+185:
		tmp = (1.0 / x) / n
	else:
		tmp = (math.log(x) / n) * 0.0
	return tmp
function code(x, n)
	tmp = 0.0
	if (x <= 0.55)
		tmp = Float64(Float64(-log(x)) / n);
	elseif (x <= 6.5e+185)
		tmp = Float64(Float64(1.0 / x) / n);
	else
		tmp = Float64(Float64(log(x) / n) * 0.0);
	end
	return tmp
end
function tmp_2 = code(x, n)
	tmp = 0.0;
	if (x <= 0.55)
		tmp = -log(x) / n;
	elseif (x <= 6.5e+185)
		tmp = (1.0 / x) / n;
	else
		tmp = (log(x) / n) * 0.0;
	end
	tmp_2 = tmp;
end
code[x_, n_] := If[LessEqual[x, 0.55], N[((-N[Log[x], $MachinePrecision]) / n), $MachinePrecision], If[LessEqual[x, 6.5e+185], N[(N[(1.0 / x), $MachinePrecision] / n), $MachinePrecision], N[(N[(N[Log[x], $MachinePrecision] / n), $MachinePrecision] * 0.0), $MachinePrecision]]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.55:\\
\;\;\;\;\frac{-\log x}{n}\\

\mathbf{elif}\;x \leq 6.5 \cdot 10^{+185}:\\
\;\;\;\;\frac{\frac{1}{x}}{n}\\

\mathbf{else}:\\
\;\;\;\;\frac{\log x}{n} \cdot 0\\


\end{array}
\end{array}
Derivation
  1. Split input into 3 regimes
  2. if x < 0.55000000000000004

    1. Initial program 43.8%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 53.7%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def53.7%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified53.7%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around 0 52.9%

      \[\leadsto \frac{\color{blue}{-1 \cdot \log x}}{n} \]
    6. Step-by-step derivation
      1. mul-1-neg52.9%

        \[\leadsto \frac{\color{blue}{-\log x}}{n} \]
    7. Simplified52.9%

      \[\leadsto \frac{\color{blue}{-\log x}}{n} \]

    if 0.55000000000000004 < x < 6.5000000000000002e185

    1. Initial program 53.9%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 55.6%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def55.6%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified55.6%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 61.1%

      \[\leadsto \frac{\color{blue}{\frac{1}{x}}}{n} \]

    if 6.5000000000000002e185 < x

    1. Initial program 89.1%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 89.1%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def89.1%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified89.1%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Step-by-step derivation
      1. log1p-def89.1%

        \[\leadsto \frac{\color{blue}{\log \left(1 + x\right)} - \log x}{n} \]
      2. div-sub86.7%

        \[\leadsto \color{blue}{\frac{\log \left(1 + x\right)}{n} - \frac{\log x}{n}} \]
      3. add-sqr-sqrt10.8%

        \[\leadsto \frac{\log \left(1 + x\right)}{n} - \color{blue}{\sqrt{\frac{\log x}{n}} \cdot \sqrt{\frac{\log x}{n}}} \]
      4. cancel-sign-sub-inv10.8%

        \[\leadsto \color{blue}{\frac{\log \left(1 + x\right)}{n} + \left(-\sqrt{\frac{\log x}{n}}\right) \cdot \sqrt{\frac{\log x}{n}}} \]
      5. log1p-def10.8%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)}}{n} + \left(-\sqrt{\frac{\log x}{n}}\right) \cdot \sqrt{\frac{\log x}{n}} \]
    6. Applied egg-rr10.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} + \left(-\sqrt{\frac{\log x}{n}}\right) \cdot \sqrt{\frac{\log x}{n}}} \]
    7. Step-by-step derivation
      1. *-commutative10.8%

        \[\leadsto \frac{\mathsf{log1p}\left(x\right)}{n} + \color{blue}{\sqrt{\frac{\log x}{n}} \cdot \left(-\sqrt{\frac{\log x}{n}}\right)} \]
    8. Simplified10.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right)}{n} + \sqrt{\frac{\log x}{n}} \cdot \left(-\sqrt{\frac{\log x}{n}}\right)} \]
    9. Taylor expanded in x around inf 86.7%

      \[\leadsto \color{blue}{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n} + \frac{\log \left(\frac{1}{x}\right)}{n}} \]
    10. Step-by-step derivation
      1. associate-*r/86.7%

        \[\leadsto \color{blue}{\frac{-1 \cdot \log \left(\frac{1}{x}\right)}{n}} + \frac{\log \left(\frac{1}{x}\right)}{n} \]
      2. log-rec86.7%

        \[\leadsto \frac{-1 \cdot \color{blue}{\left(-\log x\right)}}{n} + \frac{\log \left(\frac{1}{x}\right)}{n} \]
      3. neg-mul-186.7%

        \[\leadsto \frac{\color{blue}{-\left(-\log x\right)}}{n} + \frac{\log \left(\frac{1}{x}\right)}{n} \]
      4. remove-double-neg86.7%

        \[\leadsto \frac{\color{blue}{\log x}}{n} + \frac{\log \left(\frac{1}{x}\right)}{n} \]
      5. log-rec86.7%

        \[\leadsto \frac{\log x}{n} + \frac{\color{blue}{-\log x}}{n} \]
      6. distribute-frac-neg86.7%

        \[\leadsto \frac{\log x}{n} + \color{blue}{\left(-\frac{\log x}{n}\right)} \]
      7. mul-1-neg86.7%

        \[\leadsto \frac{\log x}{n} + \color{blue}{-1 \cdot \frac{\log x}{n}} \]
      8. *-lft-identity86.7%

        \[\leadsto \color{blue}{1 \cdot \frac{\log x}{n}} + -1 \cdot \frac{\log x}{n} \]
      9. distribute-rgt-out86.7%

        \[\leadsto \color{blue}{\frac{\log x}{n} \cdot \left(1 + -1\right)} \]
      10. metadata-eval86.7%

        \[\leadsto \frac{\log x}{n} \cdot \color{blue}{0} \]
    11. Simplified86.7%

      \[\leadsto \color{blue}{\frac{\log x}{n} \cdot 0} \]
  3. Recombined 3 regimes into one program.
  4. Final simplification60.8%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.55:\\ \;\;\;\;\frac{-\log x}{n}\\ \mathbf{elif}\;x \leq 6.5 \cdot 10^{+185}:\\ \;\;\;\;\frac{\frac{1}{x}}{n}\\ \mathbf{else}:\\ \;\;\;\;\frac{\log x}{n} \cdot 0\\ \end{array} \]

Alternative 9: 71.1% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 5 \cdot 10^{-32}:\\ \;\;\;\;\frac{-\log x}{n}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (if (<= x 5e-32) (/ (- (log x)) n) (/ (/ (pow x (/ 1.0 n)) n) x)))
double code(double x, double n) {
	double tmp;
	if (x <= 5e-32) {
		tmp = -log(x) / n;
	} else {
		tmp = (pow(x, (1.0 / n)) / n) / x;
	}
	return tmp;
}
real(8) function code(x, n)
    real(8), intent (in) :: x
    real(8), intent (in) :: n
    real(8) :: tmp
    if (x <= 5d-32) then
        tmp = -log(x) / n
    else
        tmp = ((x ** (1.0d0 / n)) / n) / x
    end if
    code = tmp
end function
public static double code(double x, double n) {
	double tmp;
	if (x <= 5e-32) {
		tmp = -Math.log(x) / n;
	} else {
		tmp = (Math.pow(x, (1.0 / n)) / n) / x;
	}
	return tmp;
}
def code(x, n):
	tmp = 0
	if x <= 5e-32:
		tmp = -math.log(x) / n
	else:
		tmp = (math.pow(x, (1.0 / n)) / n) / x
	return tmp
function code(x, n)
	tmp = 0.0
	if (x <= 5e-32)
		tmp = Float64(Float64(-log(x)) / n);
	else
		tmp = Float64(Float64((x ^ Float64(1.0 / n)) / n) / x);
	end
	return tmp
end
function tmp_2 = code(x, n)
	tmp = 0.0;
	if (x <= 5e-32)
		tmp = -log(x) / n;
	else
		tmp = ((x ^ (1.0 / n)) / n) / x;
	end
	tmp_2 = tmp;
end
code[x_, n_] := If[LessEqual[x, 5e-32], N[((-N[Log[x], $MachinePrecision]) / n), $MachinePrecision], N[(N[(N[Power[x, N[(1.0 / n), $MachinePrecision]], $MachinePrecision] / n), $MachinePrecision] / x), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 5 \cdot 10^{-32}:\\
\;\;\;\;\frac{-\log x}{n}\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 5e-32

    1. Initial program 42.8%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 54.8%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def54.8%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified54.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around 0 54.8%

      \[\leadsto \frac{\color{blue}{-1 \cdot \log x}}{n} \]
    6. Step-by-step derivation
      1. mul-1-neg54.8%

        \[\leadsto \frac{\color{blue}{-\log x}}{n} \]
    7. Simplified54.8%

      \[\leadsto \frac{\color{blue}{-\log x}}{n} \]

    if 5e-32 < x

    1. Initial program 66.2%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in x around inf 94.3%

      \[\leadsto \color{blue}{\frac{e^{-1 \cdot \frac{\log \left(\frac{1}{x}\right)}{n}}}{n \cdot x}} \]
    3. Step-by-step derivation
      1. mul-1-neg94.3%

        \[\leadsto \frac{e^{\color{blue}{-\frac{\log \left(\frac{1}{x}\right)}{n}}}}{n \cdot x} \]
      2. log-rec94.3%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-\log x}}{n}}}{n \cdot x} \]
      3. mul-1-neg94.3%

        \[\leadsto \frac{e^{-\frac{\color{blue}{-1 \cdot \log x}}{n}}}{n \cdot x} \]
      4. distribute-neg-frac94.3%

        \[\leadsto \frac{e^{\color{blue}{\frac{--1 \cdot \log x}{n}}}}{n \cdot x} \]
      5. mul-1-neg94.3%

        \[\leadsto \frac{e^{\frac{-\color{blue}{\left(-\log x\right)}}{n}}}{n \cdot x} \]
      6. remove-double-neg94.3%

        \[\leadsto \frac{e^{\frac{\color{blue}{\log x}}{n}}}{n \cdot x} \]
      7. *-commutative94.3%

        \[\leadsto \frac{e^{\frac{\log x}{n}}}{\color{blue}{x \cdot n}} \]
    4. Simplified94.3%

      \[\leadsto \color{blue}{\frac{e^{\frac{\log x}{n}}}{x \cdot n}} \]
    5. Step-by-step derivation
      1. *-un-lft-identity94.3%

        \[\leadsto \frac{\color{blue}{1 \cdot e^{\frac{\log x}{n}}}}{x \cdot n} \]
      2. times-frac95.4%

        \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{e^{\frac{\log x}{n}}}{n}} \]
      3. div-inv95.4%

        \[\leadsto \frac{1}{x} \cdot \frac{e^{\color{blue}{\log x \cdot \frac{1}{n}}}}{n} \]
      4. exp-to-pow95.4%

        \[\leadsto \frac{1}{x} \cdot \frac{\color{blue}{{x}^{\left(\frac{1}{n}\right)}}}{n} \]
    6. Applied egg-rr95.4%

      \[\leadsto \color{blue}{\frac{1}{x} \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}} \]
    7. Step-by-step derivation
      1. associate-*l/95.5%

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]
      2. *-un-lft-identity95.5%

        \[\leadsto \frac{\color{blue}{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}}{x} \]
    8. Applied egg-rr95.5%

      \[\leadsto \color{blue}{\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification74.5%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 5 \cdot 10^{-32}:\\ \;\;\;\;\frac{-\log x}{n}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{{x}^{\left(\frac{1}{n}\right)}}{n}}{x}\\ \end{array} \]

Alternative 10: 56.8% accurate, 1.9× speedup?

\[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;x \leq 0.55:\\ \;\;\;\;\frac{-\log x}{n}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{1}{x}}{n}\\ \end{array} \end{array} \]
(FPCore (x n)
 :precision binary64
 (if (<= x 0.55) (/ (- (log x)) n) (/ (/ 1.0 x) n)))
double code(double x, double n) {
	double tmp;
	if (x <= 0.55) {
		tmp = -log(x) / n;
	} else {
		tmp = (1.0 / x) / n;
	}
	return tmp;
}
real(8) function code(x, n)
    real(8), intent (in) :: x
    real(8), intent (in) :: n
    real(8) :: tmp
    if (x <= 0.55d0) then
        tmp = -log(x) / n
    else
        tmp = (1.0d0 / x) / n
    end if
    code = tmp
end function
public static double code(double x, double n) {
	double tmp;
	if (x <= 0.55) {
		tmp = -Math.log(x) / n;
	} else {
		tmp = (1.0 / x) / n;
	}
	return tmp;
}
def code(x, n):
	tmp = 0
	if x <= 0.55:
		tmp = -math.log(x) / n
	else:
		tmp = (1.0 / x) / n
	return tmp
function code(x, n)
	tmp = 0.0
	if (x <= 0.55)
		tmp = Float64(Float64(-log(x)) / n);
	else
		tmp = Float64(Float64(1.0 / x) / n);
	end
	return tmp
end
function tmp_2 = code(x, n)
	tmp = 0.0;
	if (x <= 0.55)
		tmp = -log(x) / n;
	else
		tmp = (1.0 / x) / n;
	end
	tmp_2 = tmp;
end
code[x_, n_] := If[LessEqual[x, 0.55], N[((-N[Log[x], $MachinePrecision]) / n), $MachinePrecision], N[(N[(1.0 / x), $MachinePrecision] / n), $MachinePrecision]]
\begin{array}{l}

\\
\begin{array}{l}
\mathbf{if}\;x \leq 0.55:\\
\;\;\;\;\frac{-\log x}{n}\\

\mathbf{else}:\\
\;\;\;\;\frac{\frac{1}{x}}{n}\\


\end{array}
\end{array}
Derivation
  1. Split input into 2 regimes
  2. if x < 0.55000000000000004

    1. Initial program 43.8%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 53.7%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def53.7%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified53.7%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around 0 52.9%

      \[\leadsto \frac{\color{blue}{-1 \cdot \log x}}{n} \]
    6. Step-by-step derivation
      1. mul-1-neg52.9%

        \[\leadsto \frac{\color{blue}{-\log x}}{n} \]
    7. Simplified52.9%

      \[\leadsto \frac{\color{blue}{-\log x}}{n} \]

    if 0.55000000000000004 < x

    1. Initial program 66.8%

      \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
    2. Taylor expanded in n around inf 67.8%

      \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
    3. Step-by-step derivation
      1. log1p-def67.8%

        \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
    4. Simplified67.8%

      \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
    5. Taylor expanded in x around inf 61.9%

      \[\leadsto \frac{\color{blue}{\frac{1}{x}}}{n} \]
  3. Recombined 2 regimes into one program.
  4. Final simplification57.0%

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \leq 0.55:\\ \;\;\;\;\frac{-\log x}{n}\\ \mathbf{else}:\\ \;\;\;\;\frac{\frac{1}{x}}{n}\\ \end{array} \]

Alternative 11: 39.8% accurate, 42.2× speedup?

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

\\
\frac{1}{n \cdot x}
\end{array}
Derivation
  1. Initial program 54.1%

    \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
  2. Taylor expanded in n around inf 60.0%

    \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
  3. Step-by-step derivation
    1. log1p-def60.0%

      \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
  4. Simplified60.0%

    \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
  5. Taylor expanded in x around inf 40.4%

    \[\leadsto \color{blue}{\frac{1}{n \cdot x}} \]
  6. Step-by-step derivation
    1. *-commutative40.4%

      \[\leadsto \frac{1}{\color{blue}{x \cdot n}} \]
  7. Simplified40.4%

    \[\leadsto \color{blue}{\frac{1}{x \cdot n}} \]
  8. Final simplification40.4%

    \[\leadsto \frac{1}{n \cdot x} \]

Alternative 12: 40.3% accurate, 42.2× speedup?

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

\\
\frac{\frac{1}{x}}{n}
\end{array}
Derivation
  1. Initial program 54.1%

    \[{\left(x + 1\right)}^{\left(\frac{1}{n}\right)} - {x}^{\left(\frac{1}{n}\right)} \]
  2. Taylor expanded in n around inf 60.0%

    \[\leadsto \color{blue}{\frac{\log \left(1 + x\right) - \log x}{n}} \]
  3. Step-by-step derivation
    1. log1p-def60.0%

      \[\leadsto \frac{\color{blue}{\mathsf{log1p}\left(x\right)} - \log x}{n} \]
  4. Simplified60.0%

    \[\leadsto \color{blue}{\frac{\mathsf{log1p}\left(x\right) - \log x}{n}} \]
  5. Taylor expanded in x around inf 40.9%

    \[\leadsto \frac{\color{blue}{\frac{1}{x}}}{n} \]
  6. Final simplification40.9%

    \[\leadsto \frac{\frac{1}{x}}{n} \]

Reproduce

?
herbie shell --seed 2023336 
(FPCore (x n)
  :name "2nthrt (problem 3.4.6)"
  :precision binary64
  (- (pow (+ x 1.0) (/ 1.0 n)) (pow x (/ 1.0 n))))