Re: GSoC ode15{i,s} - type conversion and approximation problems

[Carlo De Falco]

On 16 Jun 2016, at 17:25, Francesco Faccio <address@hidden> wrote:

> If the user gives in input only  [[ ], DF/DYP] or [DF/DY, [ ]], I have to 
> approximate DF/DY or DF/DYP before passing them to Sundials' solver. Matlab 
> in this case approximates them by finite differences: should I do the same or 
> maybe use another external library to do it (Sundials IDA doesn't give a 
> direct interface for its approximation functions)?

According to the documentation, IDA can apprroximate the jacobian itself if 
needed:

"In the case of the direct methods idadense and idaband, the package includes 
an algorithm for the approximation of the Jacobian by difference quotients,"

you should never re-implement yourself features that are already available.

c.