sympy/sympy — pull request #2214 by Manoj-Kumar-S (2013-06-28 11:43:46+00:00)
Title: WIP- Heuristic4

The main objective is to find chi in the equation, 'chi.diff(x) + h*chi.diff(y) - h.diff(y)*chi = 0` , and find the infintesimals by setting one of xi and eta in the equation, eta = xi*h + chi depending upon the simplicity. The first part has been done, I am working on the second part.