Average Error: 2.2 → 0.3
Time: 5.3s
Precision: binary64
\[\frac{a \cdot {k}^{m}}{\left(1 + 10 \cdot k\right) + k \cdot k}\]
\[\begin{array}{l} \mathbf{if}\;k \leq 5.218508833152239 \cdot 10^{-17}:\\ \;\;\;\;\frac{a}{\sqrt{1 + k \cdot \left(k + 10\right)}} \cdot \frac{{k}^{m}}{\sqrt{1 + k \cdot \left(k + 10\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\frac{{k}^{\left(-m\right)}}{a} + \frac{k}{{k}^{m}} \cdot \left(\frac{k}{a} + \frac{10}{a}\right)}\\ \end{array}\]
\frac{a \cdot {k}^{m}}{\left(1 + 10 \cdot k\right) + k \cdot k}
\begin{array}{l}
\mathbf{if}\;k \leq 5.218508833152239 \cdot 10^{-17}:\\
\;\;\;\;\frac{a}{\sqrt{1 + k \cdot \left(k + 10\right)}} \cdot \frac{{k}^{m}}{\sqrt{1 + k \cdot \left(k + 10\right)}}\\

\mathbf{else}:\\
\;\;\;\;\frac{1}{\frac{{k}^{\left(-m\right)}}{a} + \frac{k}{{k}^{m}} \cdot \left(\frac{k}{a} + \frac{10}{a}\right)}\\

\end{array}
(FPCore (a k m)
 :precision binary64
 (/ (* a (pow k m)) (+ (+ 1.0 (* 10.0 k)) (* k k))))
(FPCore (a k m)
 :precision binary64
 (if (<= k 5.218508833152239e-17)
   (*
    (/ a (sqrt (+ 1.0 (* k (+ k 10.0)))))
    (/ (pow k m) (sqrt (+ 1.0 (* k (+ k 10.0))))))
   (/ 1.0 (+ (/ (pow k (- m)) a) (* (/ k (pow k m)) (+ (/ k a) (/ 10.0 a)))))))
double code(double a, double k, double m) {
	return (a * pow(k, m)) / ((1.0 + (10.0 * k)) + (k * k));
}
double code(double a, double k, double m) {
	double tmp;
	if (k <= 5.218508833152239e-17) {
		tmp = (a / sqrt(1.0 + (k * (k + 10.0)))) * (pow(k, m) / sqrt(1.0 + (k * (k + 10.0))));
	} else {
		tmp = 1.0 / ((pow(k, -m) / a) + ((k / pow(k, m)) * ((k / a) + (10.0 / a))));
	}
	return tmp;
}

Error

Bits error versus a

Bits error versus k

Bits error versus m

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 2 regimes
  2. if k < 5.2185088331522393e-17

    1. Initial program 0.1

      \[\frac{a \cdot {k}^{m}}{\left(1 + 10 \cdot k\right) + k \cdot k}\]
    2. Simplified0.0

      \[\leadsto \color{blue}{\frac{a \cdot {k}^{m}}{1 + k \cdot \left(k + 10\right)}}\]
    3. Using strategy rm
    4. Applied add-sqr-sqrt_binary64_21460.1

      \[\leadsto \frac{a \cdot {k}^{m}}{\color{blue}{\sqrt{1 + k \cdot \left(k + 10\right)} \cdot \sqrt{1 + k \cdot \left(k + 10\right)}}}\]
    5. Applied times-frac_binary64_21300.1

      \[\leadsto \color{blue}{\frac{a}{\sqrt{1 + k \cdot \left(k + 10\right)}} \cdot \frac{{k}^{m}}{\sqrt{1 + k \cdot \left(k + 10\right)}}}\]

    if 5.2185088331522393e-17 < k

    1. Initial program 5.2

      \[\frac{a \cdot {k}^{m}}{\left(1 + 10 \cdot k\right) + k \cdot k}\]
    2. Simplified5.2

      \[\leadsto \color{blue}{\frac{a \cdot {k}^{m}}{1 + k \cdot \left(k + 10\right)}}\]
    3. Using strategy rm
    4. Applied clear-num_binary64_21235.4

      \[\leadsto \color{blue}{\frac{1}{\frac{1 + k \cdot \left(k + 10\right)}{a \cdot {k}^{m}}}}\]
    5. Taylor expanded around inf 5.5

      \[\leadsto \frac{1}{\color{blue}{10 \cdot \frac{k}{a \cdot e^{-1 \cdot \left(m \cdot \log \left(\frac{1}{k}\right)\right)}} + \left(\frac{{k}^{2}}{a \cdot e^{-1 \cdot \left(m \cdot \log \left(\frac{1}{k}\right)\right)}} + \frac{1}{a \cdot e^{-1 \cdot \left(m \cdot \log \left(\frac{1}{k}\right)\right)}}\right)}}\]
    6. Simplified0.5

      \[\leadsto \frac{1}{\color{blue}{\frac{{k}^{\left(-m\right)}}{a} + \frac{k}{{k}^{m}} \cdot \left(\frac{k}{a} + \frac{10}{a}\right)}}\]
  3. Recombined 2 regimes into one program.
  4. Final simplification0.3

    \[\leadsto \begin{array}{l} \mathbf{if}\;k \leq 5.218508833152239 \cdot 10^{-17}:\\ \;\;\;\;\frac{a}{\sqrt{1 + k \cdot \left(k + 10\right)}} \cdot \frac{{k}^{m}}{\sqrt{1 + k \cdot \left(k + 10\right)}}\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\frac{{k}^{\left(-m\right)}}{a} + \frac{k}{{k}^{m}} \cdot \left(\frac{k}{a} + \frac{10}{a}\right)}\\ \end{array}\]

Reproduce

herbie shell --seed 2020355 
(FPCore (a k m)
  :name "Falkner and Boettcher, Appendix A"
  :precision binary64
  (/ (* a (pow k m)) (+ (+ 1.0 (* 10.0 k)) (* k k))))