[Trilinos-Users] Questions about InsertGlobalValues

[Williams, Alan B]

> 
> then how do I go about actually generating the graph since in
> InsertGlobalIndices  column mapping is an input?

InsertGlobalIndices takes a list of column-indices for specified rows. A matrix-graph is the mapping of column-indices to rows. i.e., the sparsity-structure of the matrix.

> I would like to avoid creating column mapping because it changes as I
> iterate and would have to be updated for every iteration.

I must not understand what you're trying to do. If your column mapping changes, your matrix-graph will have to be updated (destroyed and recreated), because a matrix-graph is the mapping of columns to rows.
 
Alan