Re: I have a question about internal sparse matrix data structure in Octave

[c.]

On 17 May 2012, at 19:00, address@hidden wrote:

> Hi All,
> 
> I am trying to implement the preconditioner for Octave. And I am
> trying to figure out what format octave use for sparse matrix? Is it
> compressed sparse row?
> 

Almost, it's Compressed Sparse Column, you can traverse it like this:

SparseMatrix A (nrows, ncols, 0.0);
 ...

for (octave_idx_type j = 0; j < ncols; j++)
 for (octave_idx_type i = A.cidx (j); i < A.cidx (j+1); i++)
  std::cout << A.data(i);

> Thank you!

c.