[petsc-users] Get a smaller vector with PETSc

[Barry Smith]

  VecScatterCreate().

   If you wish the sub vector to live on a single process then create a sequential vector of the appropriate size on that one process and sequential vectors of size zero on all other processes and scatter into them.

   Barry

On Oct 2, 2013, at 6:27 AM, Rui Emanuel Ferreira da Silva <rui.silva at uam.es> wrote:

> I am writing to you to ask some technical problems that I am dealing
> with the use of PETSc.
> 
> The problem that I am facing is the following: I have defined a vector in Petsc which was created with VecCreateMPI. After that, I read this vector from an external file with a PETSc viewer.
> 
> So if the initial vector is V with size N, I want to obtain a smaller vector U with size M, where M<N. I have an array of integers that are the indexes of V that I want to pass to U.
> 
> How can I do this?
> 
> Regards
> 
> -------------------
> Rui Silva
> EMTCCM (European Master in Theoretical Chemistry and Computational Modelling)
> UAM, Departamento de Química, Módulo 13
> CAMPUS http://www.uam.es/departamentos/ciencias/quimica/spline/index.html
> -------------------
>