The Matlab function for displaying the shape of a sparse matrix A is spy(A);
connected there are many functions useful in handling spare matrices. For instance nnz(A) gives the number of the nonzero elements. Moreover if you need to manipulate sparse matrices there are a lot of specific function of the package "sparse". (search sparse in the Matlab help)
Thanks to all...spy was the most popular result when I googled it before posting.... it would be great if someone can show some worked out examples (small ones ) where numerical values of elements of a sparse matrix can be seen by zooming. spy shows sparsity pattern only..right ?
If you want to see the values of the entries you can use the variable editor in Matlab.
In the workspace windows the variables appear with their names and dimension. If you double click on the variable, the variable editor becomes active and you can check the values of the entries.