[petsc-dev] Sub Matrix

[Jose David Bermeol]

Hi I would like to Solve a linear system of equations, but I want to do it over a sub-matrix, actually over the matrix without the rows that belongs to the first an last mpi process(I have more than 2 mpi process) and without some of the first and last columns.

For instance if my square matrix have the following form, I would like to solve a system with the matrix H(the one full of X), this matrix would be also sparse.


|      |               |     | proc 0
|      |               |     |
------------------------------
|      |xxxxxxxxxxxxxxx|     | proc 1
|      |xxxxxxxxxxxxxxx|     |
--------------H---------------
|      |xxxxxxxxxxxxxxx|     |proc 2
|      |xxxxxxxxxxxxxxx|     |
------------------------------
|      |               |     |proc 3
|      |               |     |

So is it possible to solve a system with this matrix without having to duplicate the data and move data, actually I could use just process 1 and 2 in order to solve the problem. 

Thanks