[Trilinos-Users] Hi I am New An Probably Need Your Help

[Michael A Heroux]

Davood,

Regarding your first question, there are two ways to address this issue:

1. The Epetra_CrsMatrix class takes as a first argument a View or Copy
value.  If you use the View value, your CRS matrix can be wrapped as an
Epetra_CrsMatrix without copying the data.  There is some overhead in
processing, but this can generally be handled easily.
2. You can wrap your own matrix data by writing an adapter class for the
Epetra_RowMatrix interface.  If you are familiar with C++ programming, this
task is very straight forward.  If not, which appears to be your case, then
this may be difficult.  The helper class Epetra_BasicRowMatrix makes the
process much simpler by providing default implementations of most of the
methods in Epetra_RowMatrix.  Epetra_RowMatrix is a pure virtual base class
that is used by all other parts of Trilinos to access sparse matrix data and
operations.  Thus, if you data is wrapped in this way, you can use all of
Trilinos.

Regarding your second question, there are many solver packages available.
Trilinos is most often compared to PETSc and SLEPc for the functionality you
are talking about.  I am not aware of a detailed comparison, and such
comparisons are hard to make without knowing the specifics of what you want
to do.  Although you are apparently new to OOP, if you have an interest in
exploring C++ and OO programming, I think Trilinos is extremely attractive.
If not, you may find that other packages are better for your needs as they
may take less time to learn.

Best regards,

Mike


On 11/25/07 9:57 PM, "Davood Ansari" <david.ansari at gmail.com> wrote:

> Hi every one
>  
> I am pretty new to Trilinos and OOP.
> I am doing FE analysis in the field of microwaves and I would love to know if
> the packages in here can ease or boost the performance of my work.
> I found that most sub packages need the matrix to be ready
> in as Epetra matrix objects. My question:
>  
> 1.
> I already have my CRS (usual crs consisting of a values arrays, a row_Index
> array and a
> columns array) format matrices. I would like to know if there is an effcient
> way of converting
> them into a Epetra CRS Matrix object ? Pleas comment .
>  
> 2. Does any body have any idea on how Trilinos packages (particularly solvers,
> eigne solvers and preconditioners ) compare (and compete) with other available
> packages ?
>  
> Sincerely Yours
> Davood
> 
> 
> _______________________________________________
> Trilinos-Users mailing list
> Trilinos-Users at software.sandia.gov
> http://software.sandia.gov/mailman/listinfo/trilinos-users


-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://software.sandia.gov/mailman/private/trilinos-users/attachments/20071126/0dbd5a0b/attachment.html