Mathematics

Function Summary

The sparse matrix functions are located in the sparfun directory in the MATLAB toolbox directory.

Function Summary  

Category	Function	Description
Elementary sparse matrices	speye	Sparse identity matrix.
	sprand	Sparse uniformly distributed random matrix.
	sprandn	Sparse normally distributed random matrix.
	sprandsym	Sparse random symmetric matrix.
	spdiags	Sparse matrix formed from diagonals.
Full to sparse conversion	sparse	Create sparse matrix.
	full	Convert sparse matrix to full matrix.
	find	Find indices of nonzero elements.
	spconvert	Import from sparse matrix external format.
Working with sparse matrices	nnz	Number of nonzero matrix elements.
	nonzeros	Nonzero matrix elements.
	nzmax	Amount of storage allocated for nonzero matrix elements.
	spones	Replace nonzero sparse matrix elements with ones.
	spalloc	Allocate space for sparse matrix.
	issparse	True for sparse matrix.
	spfun	Apply function to nonzero matrix elements.
	spy	Visualize sparsity pattern.
Graph theory	gplot	Plot graph, as in "graph theory."
	etree	Elimination tree.
	etreeplot	Plot elimination tree.
	treelayout	Lay out tree or forest.
	treeplot	Plot picture of tree.
Reordering algorithms	colamd	Column approximate minimum degree permutation.
	colmmd	Column minimum degree permutation.
	symamd	Symmetric approximate minimum degree permutation.
	symmmd	Symmetric minimum degree permutation.
	symrcm	Symmetric reverse Cuthill-McKee permutation.
	colperm	Column permutation.
	randperm	Random permutation.
	dmperm	Dulmage-Mendelsohn permutation.
Linear algebra	eigs	A few eigenvalues.
	svds	A few singular values.
	luinc	Incomplete LU factorization.
	cholinc	Incomplete Cholesky factorization.
	normest	Estimate the matrix 2-norm.
	condest	1-norm condition number estimate.
	sprank	Structural rank.
Linear equations (iterative methods)	bicg	BiConjugate Gradients Method.
	bicgstab	BiConjugate Gradients Stabilized Method.
	cgs	Conjugate Gradients Squared Method.
	gmres	Generalized Minimum Residual Method.
	lsqr	LSQR implementation of Conjugate Gradients on the Normal Equations.
	minres	Minimum Residual Method.
	pcg	Preconditioned Conjugate Gradients Method.
	qmr	Quasi-Minimal Residual Method.
	symmlq	Symmetric LQ method
Miscellaneous	spaugment	Form least squares augmented system.
	spparms	Set parameters for sparse matrix routines.
	symbfact	Symbolic factorization analysis.

Sparse Matrices

Introduction