Error

Try it out

Target

Derivation

1. Split input into 3 regimes

2. if x < -1.0625048377659714

   1. Initial program 61.6

      \[\log \left(x + \sqrt{x \cdot x + 1}\right)\]

   2. Initial simplification60.8

      \[\leadsto \log \left(x + \sqrt{1^2 + x^2}^*\right)\]
   3. Using strategy rm

   4. Applied expm1-log1p-u60.8

      \[\leadsto \log \color{blue}{\left((e^{\log_* (1 + \left(x + \sqrt{1^2 + x^2}^*\right))} - 1)^*\right)}\]

   5. Taylor expanded around -inf 0.2

      \[\leadsto \log \color{blue}{\left(\frac{1}{8} \cdot \frac{1}{{x}^{3}} - \left(\frac{1}{16} \cdot \frac{1}{{x}^{5}} + \frac{1}{2} \cdot \frac{1}{x}\right)\right)}\]

   6. Simplified0.2

      \[\leadsto \log \color{blue}{\left(\frac{\frac{-1}{2}}{x} + \left(\frac{\frac{-1}{16}}{{x}^{5}} + \frac{\frac{\frac{1}{8}}{x}}{x \cdot x}\right)\right)}\]

   if -1.0625048377659714 < x < 0.0068859952345695676

   1. Initial program 58.7

      \[\log \left(x + \sqrt{x \cdot x + 1}\right)\]

   2. Initial simplification58.7

      \[\leadsto \log \left(x + \sqrt{1^2 + x^2}^*\right)\]

   3. Taylor expanded around 0 0.1

      \[\leadsto \color{blue}{\left(x + \frac{3}{40} \cdot {x}^{5}\right) - \frac{1}{6} \cdot {x}^{3}}\]

   if 0.0068859952345695676 < x

   1. Initial program 30.8

      \[\log \left(x + \sqrt{x \cdot x + 1}\right)\]

   2. Initial simplification0.1

      \[\leadsto \log \left(x + \sqrt{1^2 + x^2}^*\right)\]
   3. Using strategy rm

   4. Applied expm1-log1p-u0.1

      \[\leadsto \log \color{blue}{\left((e^{\log_* (1 + \left(x + \sqrt{1^2 + x^2}^*\right))} - 1)^*\right)}\]
3. Recombined 3 regimes into one program.

4. Final simplification0.1

   \[\leadsto \begin{array}{l} \mathbf{if}\;x \le -1.0625048377659714:\\ \;\;\;\;\log \left(\frac{\frac{-1}{2}}{x} + \left(\frac{\frac{\frac{1}{8}}{x}}{x \cdot x} + \frac{\frac{-1}{16}}{{x}^{5}}\right)\right)\\ \mathbf{elif}\;x \le 0.0068859952345695676:\\ \;\;\;\;\left(x + {x}^{5} \cdot \frac{3}{40}\right) - {x}^{3} \cdot \frac{1}{6}\\ \mathbf{else}:\\ \;\;\;\;\log \left((e^{\log_* (1 + \left(\sqrt{1^2 + x^2}^* + x\right))} - 1)^*\right)\\ \end{array}\]

Runtime

Time bar (total: 17.8s)Debug logProfile

herbie shell --seed 2018295 +o rules:numerics
(FPCore (x)
  :name "Hyperbolic arcsine"

  :herbie-target
  (if (< x 0) (log (/ -1 (- x (sqrt (+ (* x x) 1))))) (log (+ x (sqrt (+ (* x x) 1)))))

  (log (+ x (sqrt (+ (* x x) 1)))))