numerical-mathematics / extrapolation

Parallel extrapolation for ODEs
MIT License
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Implicit method scipy fsolve problems #18

Open mcr222 opened 8 years ago

mcr222 commented 8 years ago

Functions to modify: _solve_implicit_step

Code TODO comment (remove once issue is closed):

TODO: Problem -> fsolve doesn't seem to work well with xtol parameter

#TODO: pass to the zero finder solver the tolerance required to the overall problem 
# by doing this the error by the solver doesn't limit the global error of the ODE's solution

#TODO change solver so it doesn't do the 2 extra unnecessary function evaluations
#https://github.com/scipy/scipy/issues/5369

Observation: currently scipy fsolve code doesn't count the 2 extra function evaluations internally made. They should be added in our code. They haven't been added yet because to provide a fair comparison of the number of function evaluations made by this code, the 2 extra (unnecessary) function evaluations could be avoided.