Average Error: 14.8 → 0.0
Time: 22.6s
Precision: 64
Internal Precision: 576
\[\frac{x}{x \cdot x + 1}\]
\[\begin{array}{l} \mathbf{if}\;x \le -3.183642330287799 \cdot 10^{+62} \lor \neg \left(x \le 421.4880034281522\right):\\ \;\;\;\;\left(\frac{1}{x} + \frac{1}{{x}^{5}}\right) - \frac{1}{{x}^{3}}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{x \cdot x + 1}\\ \end{array}\]

Error

Bits error versus x

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Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original14.8
Target0.1
Herbie0.0
\[\frac{1}{x + \frac{1}{x}}\]

Derivation

  1. Split input into 2 regimes
  2. if x < -3.183642330287799e+62 or 421.4880034281522 < x

    1. Initial program 32.6

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

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

    if -3.183642330287799e+62 < x < 421.4880034281522

    1. Initial program 0.0

      \[\frac{x}{x \cdot x + 1}\]
  3. Recombined 2 regimes into one program.
  4. Final simplification0.0

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \le -3.183642330287799 \cdot 10^{+62} \lor \neg \left(x \le 421.4880034281522\right):\\ \;\;\;\;\left(\frac{1}{x} + \frac{1}{{x}^{5}}\right) - \frac{1}{{x}^{3}}\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{x \cdot x + 1}\\ \end{array}\]

Runtime

Time bar (total: 22.6s)Debug logProfile

herbie shell --seed 2018249 
(FPCore (x)
  :name "x / (x^2 + 1)"

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

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