Average Error: 17.5 → 0.3
Time: 54.9s
Precision: 64
\[\left(J \cdot \left(e^{\ell} - e^{-\ell}\right)\right) \cdot \cos \left(\frac{K}{2}\right) + U\]
\[\left((\frac{1}{60} \cdot \left({\ell}^{5}\right) + \left(\ell \cdot 2 + \left(\frac{1}{3} \cdot \left(\ell \cdot \ell\right)\right) \cdot \ell\right))_* \cdot J\right) \cdot \cos \left(\frac{K}{2}\right) + U\]

Error

Bits error versus J

Bits error versus l

Bits error versus K

Bits error versus U

Derivation

  1. Initial program 17.5

    \[\left(J \cdot \left(e^{\ell} - e^{-\ell}\right)\right) \cdot \cos \left(\frac{K}{2}\right) + U\]
  2. Taylor expanded around 0 0.3

    \[\leadsto \left(J \cdot \color{blue}{\left(2 \cdot \ell + \left(\frac{1}{3} \cdot {\ell}^{3} + \frac{1}{60} \cdot {\ell}^{5}\right)\right)}\right) \cdot \cos \left(\frac{K}{2}\right) + U\]
  3. Simplified0.3

    \[\leadsto \left(J \cdot \color{blue}{(\frac{1}{60} \cdot \left({\ell}^{5}\right) + \left(\ell \cdot (\frac{1}{3} \cdot \left(\ell \cdot \ell\right) + 2)_*\right))_*}\right) \cdot \cos \left(\frac{K}{2}\right) + U\]
  4. Using strategy rm
  5. Applied fma-udef0.3

    \[\leadsto \left(J \cdot (\frac{1}{60} \cdot \left({\ell}^{5}\right) + \left(\ell \cdot \color{blue}{\left(\frac{1}{3} \cdot \left(\ell \cdot \ell\right) + 2\right)}\right))_*\right) \cdot \cos \left(\frac{K}{2}\right) + U\]
  6. Applied distribute-lft-in0.3

    \[\leadsto \left(J \cdot (\frac{1}{60} \cdot \left({\ell}^{5}\right) + \color{blue}{\left(\ell \cdot \left(\frac{1}{3} \cdot \left(\ell \cdot \ell\right)\right) + \ell \cdot 2\right)})_*\right) \cdot \cos \left(\frac{K}{2}\right) + U\]
  7. Final simplification0.3

    \[\leadsto \left((\frac{1}{60} \cdot \left({\ell}^{5}\right) + \left(\ell \cdot 2 + \left(\frac{1}{3} \cdot \left(\ell \cdot \ell\right)\right) \cdot \ell\right))_* \cdot J\right) \cdot \cos \left(\frac{K}{2}\right) + U\]

Reproduce

herbie shell --seed 2019100 +o rules:numerics
(FPCore (J l K U)
  :name "Maksimov and Kolovsky, Equation (4)"
  (+ (* (* J (- (exp l) (exp (- l)))) (cos (/ K 2))) U))