Symmetric, compressed, sparse column matrices

Description

The sscMatrix class is a class of symmetric, sparse matrices in the compressed, column-oriented format. In this implementation the non-zero elements in the columns are sorted into increasing row order.

Objects from the Class

Objects can be created by calls of the form new("sscMatrix", ...).

Slots

uplo:

A character object indicating if the upper triangle ("U" or "u") or the lower triangle ("L" or "l") is stored. At present only the lower triangle form is allowed.

p:

Object of class "integer" of pointers, one for each column, to the initial (zero-based) index of elements in the column.

i:

Object of class "integer" of length nnzero (number of non-zero elements). These are the row numbers for each non-zero element in the matrix.

x:

Object of class "numeric" - the non-zero elements of the matrix.

factorization:

Object of class "list" - a list of factorizations of the matrix.

Dim:

Object of class "integer" - the dimensions of the matrix - must be an integer vector with exactly two non-negative values.

Extends

Class "cscMatrix", directly.

Methods

solve

signature(a = "sscMatrix", b = "matrix"): Solve a linear system of equations defined by x using a Cholesky decomposition.

chol

signature(x = "sscMatrix", pivot = "logical"): Returns (and stores) the Cholesky decomposition of the matrix x. If pivot is TRUE (the default) Metis is used to create a reordering of the rows and columns of x so as to minimize fill-in.

coerce

signature(from = "sscMatrix", to = "tripletMatrix")

coerce

signature(from = "sscMatrix", to = "geMatrix")

See Also

cscMatrix-class, tripletMatrix-class, geMatrix-class