---------------------------------------------------------------- Elementary Sparse Matrices ---------------------------------------------------------------- spdiags Sparse matrix formed from diagonals. speye Sparse identity matrix. sprandn Sparse random matrix. sprandsym Sparse symmetric random matrix. ----------------------------------------------------------------
--------------------------------------------------------------------------- Full to Sparse Conversion --------------------------------------------------------------------------- find Find indices of nonzero entries. full Convert sparse matrix to full matrix. sparse Create sparse matrix from nonzeros and indices. spconvert Convert from sparse matrix external format. ---------------------------------------------------------------------------
------------------------------------------------------------------------------------------------- Working with Nonzero Entries of Sparse Matrices ------------------------------------------------------------------------------------------------- issparse True if matrix is sparse. nnz Number of nonzero entries. nonzeros Nonzero entries. nzmax Amount of storage allocated for nonzero entries. spalloc Allocate memory for nonzero entries. spfun Apply function to nonzero entries. spones Replace nonzero entries with ones. -------------------------------------------------------------------------------------------------
------------------------------------------------------------- Visualizing Sparse Matrices ------------------------------------------------------------- gplot Plot graph, as in "graph theory." spy Visualize sparsity structure. -------------------------------------------------------------
------------------------------------------------------------ Reordering Algorithms ------------------------------------------------------------ colmmd Column minimum degree. colperm Order columns based on nonzero count. dmperm Dulmage-Mendelsohn decomposition. randperm Random permutation vector. symmmd Symmetric minimum degree. symrcm Reverse Cuthill-McKee ordering. ------------------------------------------------------------
------------------------------------------------------------ Norm, Condition Number, and Rank ------------------------------------------------------------ condest Estimate 1-norm condition. normest Estimate 2-norm. sprank Structural rank. ------------------------------------------------------------
--------------------------------------------------------- Miscellaneous --------------------------------------------------------- spaugment Form least squares augmented system. spparms Set parameters for sparse matrix routines. symbfact Symbolic factorization analysis. ---------------------------------------------------------
(c) Copyright 1994 by The MathWorks, Inc.