A.1.6.3 Using Sparse Matrices in Oct-Files

Most of the same operators and functions on sparse matrices that are available from the Octave are equally available with oct-files. The basic means of extracting a sparse matrix from an octave_value and returning them as an octave_value, can be seen in the following example.

     octave_value_list retval;
     
     SparseMatrix sm = args(0).sparse_matrix_value ();
     SparseComplexMatrix scm =
         args(1).sparse_complex_matrix_value ();
     SparseBoolMatrix sbm = args(2).sparse_bool_matrix_value ();
     ...
     retval(2) = sbm;
     retval(1) = scm;
     retval(0) = sm;

The conversion to an octave-value is handled by the sparse octave_value constructors, and so no special care is needed.