Average Error: 15.0 → 0.0
Time: 12.5s
Precision: 64
Internal Precision: 576
\[\frac{x}{x \cdot x + 1}\]
\[\begin{array}{l} \mathbf{if}\;x \le -1.8329901161772057 \cdot 10^{+47} \lor \neg \left(x \le 536801.227964242\right):\\ \;\;\;\;\left(\frac{1}{{x}^{5}} + \frac{1}{x}\right) - \frac{1}{{x}^{3}}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{x \cdot x + 1}\\ \end{array}\]

Error

Bits error versus x

Target

Original15.0
Target0.1
Herbie0.0
\[\frac{1}{x + \frac{1}{x}}\]

Derivation

  1. Split input into 2 regimes
  2. if x < -1.8329901161772057e+47 or 536801.227964242 < x

    1. Initial program 32.7

      \[\frac{x}{x \cdot x + 1}\]
    2. Taylor expanded around inf 0.0

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

    if -1.8329901161772057e+47 < x < 536801.227964242

    1. Initial program 0.0

      \[\frac{x}{x \cdot x + 1}\]
  3. Recombined 2 regimes into one program.
  4. Applied simplify0.0

    \[\leadsto \color{blue}{\begin{array}{l} \mathbf{if}\;x \le -1.8329901161772057 \cdot 10^{+47} \lor \neg \left(x \le 536801.227964242\right):\\ \;\;\;\;\left(\frac{1}{{x}^{5}} + \frac{1}{x}\right) - \frac{1}{{x}^{3}}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{x \cdot x + 1}\\ \end{array}}\]

Runtime

Time bar (total: 12.5s)Debug logProfile

herbie shell --seed '#(1072107073 2127697367 3936270018 2300570620 2134894798 4023771849)' 
(FPCore (x)
  :name "x / (x^2 + 1)"

  :herbie-target
  (/ 1 (+ x (/ 1 x)))

  (/ x (+ (* x x) 1)))