Average Error: 37.3 → 0.4
Time: 45.6s
Precision: 64
Internal Precision: 2368
\[\tan \left(x + \varepsilon\right) - \tan x\]
\[\frac{\frac{\sin \varepsilon \cdot \cos x}{\cos \varepsilon} + \left(\tan \varepsilon \cdot \sin x\right) \cdot \tan x}{\cos x - \tan \varepsilon \cdot \left(\tan x \cdot \cos x\right)}\]

Error

Bits error versus x

Bits error versus eps

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Your Program's Arguments

Results

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Target

Original37.3
Target15.2
Herbie0.4
\[\frac{\sin \varepsilon}{\cos x \cdot \cos \left(x + \varepsilon\right)}\]

Derivation

  1. Initial program 37.3

    \[\tan \left(x + \varepsilon\right) - \tan x\]
  2. Using strategy rm
  3. Applied tan-sum22.0

    \[\leadsto \color{blue}{\frac{\tan x + \tan \varepsilon}{1 - \tan x \cdot \tan \varepsilon}} - \tan x\]
  4. Using strategy rm
  5. Applied add-log-exp22.1

    \[\leadsto \frac{\tan x + \tan \varepsilon}{1 - \color{blue}{\log \left(e^{\tan x \cdot \tan \varepsilon}\right)}} - \tan x\]
  6. Using strategy rm
  7. Applied tan-quot22.2

    \[\leadsto \frac{\tan x + \tan \varepsilon}{1 - \log \left(e^{\tan x \cdot \tan \varepsilon}\right)} - \color{blue}{\frac{\sin x}{\cos x}}\]
  8. Applied frac-sub22.3

    \[\leadsto \color{blue}{\frac{\left(\tan x + \tan \varepsilon\right) \cdot \cos x - \left(1 - \log \left(e^{\tan x \cdot \tan \varepsilon}\right)\right) \cdot \sin x}{\left(1 - \log \left(e^{\tan x \cdot \tan \varepsilon}\right)\right) \cdot \cos x}}\]
  9. Simplified20.8

    \[\leadsto \frac{\color{blue}{\left(\left(\tan \varepsilon + \tan x\right) \cdot \cos x - \sin x\right) + \left(\tan \varepsilon \cdot \sin x\right) \cdot \tan x}}{\left(1 - \log \left(e^{\tan x \cdot \tan \varepsilon}\right)\right) \cdot \cos x}\]
  10. Simplified20.7

    \[\leadsto \frac{\left(\left(\tan \varepsilon + \tan x\right) \cdot \cos x - \sin x\right) + \left(\tan \varepsilon \cdot \sin x\right) \cdot \tan x}{\color{blue}{\cos x - \tan \varepsilon \cdot \left(\cos x \cdot \tan x\right)}}\]
  11. Taylor expanded around inf 0.4

    \[\leadsto \frac{\color{blue}{\frac{\cos x \cdot \sin \varepsilon}{\cos \varepsilon}} + \left(\tan \varepsilon \cdot \sin x\right) \cdot \tan x}{\cos x - \tan \varepsilon \cdot \left(\cos x \cdot \tan x\right)}\]
  12. Final simplification0.4

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

Runtime

Time bar (total: 45.6s)Debug logProfile

herbie shell --seed 2018221 
(FPCore (x eps)
  :name "2tan (problem 3.3.2)"

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

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