"Alejandro " <email@example.com> wrote in message <firstname.lastname@example.org>... > Hi all, > > Say I created a sparse matrix (say K) in a mex file and returned to matlab environment. I read that sparse matrix has no information of the sparsity and cannot be used in any other matlab function that uses a sparse matrix.
Wrong. If the sparse matrix was created correctly in the mex routine, you can use it just like any other sparse matrix that was created at the m-file level. You can use the FEX function spok to see if it was built properly: