Average Error: 37.1 → 14.6
Time: 38.5s
Precision: 64
Internal Precision: 2368
\[\tan \left(x + \varepsilon\right) - \tan x\]
\[\begin{array}{l} \mathbf{if}\;\varepsilon \le -3.848860041120697 \cdot 10^{-74}:\\ \;\;\;\;\frac{\cos x \cdot \left(\tan \varepsilon + \tan x\right) - \left(1 - \tan \varepsilon \cdot \tan x\right) \cdot \sin x}{\left(1 - \tan \varepsilon \cdot \tan x\right) \cdot \cos x}\\ \mathbf{elif}\;\varepsilon \le 1.0275046713596955 \cdot 10^{-89}:\\ \;\;\;\;\left(\varepsilon \cdot \varepsilon\right) \cdot \left(x + \varepsilon \cdot \frac{1}{3}\right) + \varepsilon\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\frac{1 - \tan \varepsilon \cdot \tan x}{\tan \varepsilon + \tan x}} - \tan x\\ \end{array}\]

Error

Bits error versus x

Bits error versus eps

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Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original37.1
Target15.0
Herbie14.6
\[\frac{\sin \varepsilon}{\cos x \cdot \cos \left(x + \varepsilon\right)}\]

Derivation

  1. Split input into 3 regimes
  2. if eps < -3.848860041120697e-74

    1. Initial program 31.0

      \[\tan \left(x + \varepsilon\right) - \tan x\]
    2. Initial simplification31.0

      \[\leadsto \tan \left(\varepsilon + x\right) - \tan x\]
    3. Using strategy rm
    4. Applied tan-quot30.8

      \[\leadsto \tan \left(\varepsilon + x\right) - \color{blue}{\frac{\sin x}{\cos x}}\]
    5. Applied tan-sum5.9

      \[\leadsto \color{blue}{\frac{\tan \varepsilon + \tan x}{1 - \tan \varepsilon \cdot \tan x}} - \frac{\sin x}{\cos x}\]
    6. Applied frac-sub6.0

      \[\leadsto \color{blue}{\frac{\left(\tan \varepsilon + \tan x\right) \cdot \cos x - \left(1 - \tan \varepsilon \cdot \tan x\right) \cdot \sin x}{\left(1 - \tan \varepsilon \cdot \tan x\right) \cdot \cos x}}\]

    if -3.848860041120697e-74 < eps < 1.0275046713596955e-89

    1. Initial program 48.0

      \[\tan \left(x + \varepsilon\right) - \tan x\]
    2. Initial simplification48.0

      \[\leadsto \tan \left(\varepsilon + x\right) - \tan x\]
    3. Using strategy rm
    4. Applied tan-sum48.0

      \[\leadsto \color{blue}{\frac{\tan \varepsilon + \tan x}{1 - \tan \varepsilon \cdot \tan x}} - \tan x\]
    5. Using strategy rm
    6. Applied tan-quot48.0

      \[\leadsto \frac{\tan \varepsilon + \tan x}{1 - \color{blue}{\frac{\sin \varepsilon}{\cos \varepsilon}} \cdot \tan x} - \tan x\]
    7. Applied associate-*l/48.0

      \[\leadsto \frac{\tan \varepsilon + \tan x}{1 - \color{blue}{\frac{\sin \varepsilon \cdot \tan x}{\cos \varepsilon}}} - \tan x\]
    8. Using strategy rm
    9. Applied add-cbrt-cube48.0

      \[\leadsto \frac{\tan \varepsilon + \tan x}{1 - \color{blue}{\sqrt[3]{\left(\frac{\sin \varepsilon \cdot \tan x}{\cos \varepsilon} \cdot \frac{\sin \varepsilon \cdot \tan x}{\cos \varepsilon}\right) \cdot \frac{\sin \varepsilon \cdot \tan x}{\cos \varepsilon}}}} - \tan x\]
    10. Taylor expanded around 0 27.8

      \[\leadsto \color{blue}{x \cdot {\varepsilon}^{2} + \left(\frac{1}{3} \cdot {\varepsilon}^{3} + \varepsilon\right)}\]
    11. Simplified27.8

      \[\leadsto \color{blue}{\varepsilon + \left(\varepsilon \cdot \varepsilon\right) \cdot \left(x + \frac{1}{3} \cdot \varepsilon\right)}\]

    if 1.0275046713596955e-89 < eps

    1. Initial program 30.3

      \[\tan \left(x + \varepsilon\right) - \tan x\]
    2. Initial simplification30.3

      \[\leadsto \tan \left(\varepsilon + x\right) - \tan x\]
    3. Using strategy rm
    4. Applied tan-sum7.3

      \[\leadsto \color{blue}{\frac{\tan \varepsilon + \tan x}{1 - \tan \varepsilon \cdot \tan x}} - \tan x\]
    5. Using strategy rm
    6. Applied *-un-lft-identity7.3

      \[\leadsto \frac{\color{blue}{1 \cdot \left(\tan \varepsilon + \tan x\right)}}{1 - \tan \varepsilon \cdot \tan x} - \tan x\]
    7. Applied associate-/l*7.3

      \[\leadsto \color{blue}{\frac{1}{\frac{1 - \tan \varepsilon \cdot \tan x}{\tan \varepsilon + \tan x}}} - \tan x\]
  3. Recombined 3 regimes into one program.
  4. Final simplification14.6

    \[\leadsto \begin{array}{l} \mathbf{if}\;\varepsilon \le -3.848860041120697 \cdot 10^{-74}:\\ \;\;\;\;\frac{\cos x \cdot \left(\tan \varepsilon + \tan x\right) - \left(1 - \tan \varepsilon \cdot \tan x\right) \cdot \sin x}{\left(1 - \tan \varepsilon \cdot \tan x\right) \cdot \cos x}\\ \mathbf{elif}\;\varepsilon \le 1.0275046713596955 \cdot 10^{-89}:\\ \;\;\;\;\left(\varepsilon \cdot \varepsilon\right) \cdot \left(x + \varepsilon \cdot \frac{1}{3}\right) + \varepsilon\\ \mathbf{else}:\\ \;\;\;\;\frac{1}{\frac{1 - \tan \varepsilon \cdot \tan x}{\tan \varepsilon + \tan x}} - \tan x\\ \end{array}\]

Runtime

Time bar (total: 38.5s)Debug logProfile

BaselineHerbieOracleSpan%
Regimes22.214.613.88.490.3%
herbie shell --seed 2018297 
(FPCore (x eps)
  :name "2tan (problem 3.3.2)"

  :herbie-target
  (/ (sin eps) (* (cos x) (cos (+ x eps))))

  (- (tan (+ x eps)) (tan x)))