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Sparse Matrix Functions


Elementary Sparse Matrices
spdiags Extract and create sparse band and diagonal matrices
speye Sparse identity matrix
sprand Sparse uniformly distributed random matrix
sprandn Sparse normally distributed random matrix
sprandsym Sparse symmetric random matrix

Full to Sparse Conversion
find Find indices and values of nonzero elements
full Convert sparse matrix to full matrix
sparse Create sparse matrix
spconvert Import matrix from sparse matrix external format

Working with Nonzero Entries of Sparse Matrices
nnz Number of nonzero matrix elements
nonzeros Nonzero matrix elements
nzmax Amount of storage allocated for nonzero matrix elements
spalloc Allocate space for sparse matrix
spfun Apply function to nonzero sparse matrix elements
spones Replace nonzero sparse matrix elements with ones

Visualizing Sparse Matrices
spy Visualize sparsity pattern

Reordering Algorithms
colmmd Sparse column minimum degree permutation
colperm Sparse column permutation based on nonzero count
dmperm Dulmage-Mendelsohn decomposition
randperm Random permutation
symmmd Sparse symmetric minimum degree ordering
symrcm Sparse reverse Cuthill-McKee ordering

Norm, Condition Number, and Rank
condest 1-norm matrix condition number estimate
normest 2-norm estimate

Sparse Systems of Linear Equations
bicg BiConjugate Gradients method
bicgstab BiConjugate Gradients Stabilized method
cgs Conjugate Gradients Squared method
cholinc Incomplete Cholesky factorizations
gmres Generalized Minimum Residual method (with restarts)
luinc Incomplete LU matrix factorizations
pcg Preconditioned Conjugate Gradients method
qmr Quasi-Minimal Residual method

Sparse Eigenvalues and Singular Values
eigs Find a few eigenvalues and eigenvectors
svds A few singular values

Miscellaneous
spparms Set parameters for sparse matrix routines