[Trilinos-Users] question on extracting submatrices

[rrossi at cimne.upc.edu]

Dear all,

i am a new user of the Epetra, Amesos, Aztect and IFpack which we are
currently using as an option for our  nonlinear FE analysis in parallel.

First of all my felicitations to the developers. We found the interface
very good and much simpler than alternatives we looked at (PETSC)

I'd like however to ask a practical question to see if i can make
effective use also of the meros package ;-)

suppose i have a matrix of type Epetra_FECrsMatrix distributed between two
processor

say that such matrix is

A =
1   2  3  4
5   6  7  8
9   10 11 12
13  14 15 16 17

distributed so that the first 2 lines are on proc0 and the others on proc1

i would like to create a new matrix containing (say) the first and third
rows and columns of A

defined for exampel as

B =
1 3
9 11

or another containing (say the elements)
G =
4
12

where all the elements of B can stay on the same processors they were in A

does it exist any "easy" way of doing this?

thanks
Riccardo