Class "matrix.csc" - Sparse Matrices in [C]ompressed [S]parse [C]olumn Format

A class for sparse matrices stored in compressed sparse column ('csc') format.

Objects from the Class

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

Slots

ra:

Object of class numeric, a real array of nnz elements containing the non-zero elements of A, stored in column order. Thus, if i<j, all elements of column i precede elements from column j. The order of elements within the column is immaterial.

ja:

Object of class integer, an integer array of nnz elements containing the row indices of the elements stored in `ra'.

ia:

Object of class integer, an integer array of n+1 elements containing pointers to the beginning of each column in the arrays `ra' and `ja'. Thus `ia[i]' indicates the position in the arrays `ra' and `ja' where the ith column begins. The last, (n+1)st, element of `ia' indicates where the n+1 column would start, if it existed.

dimension:

Object of class integer, dimension of the matrix

Methods

as.matrix.csr

signature(x = "matrix.csc"): ...

as.matrix.ssc

signature(x = "matrix.csc"): ...

as.matrix.ssr

signature(x = "matrix.csc"): ...

as.matrix

signature(x = "matrix.csc"): ...

chol

signature(x = "matrix.csc"): ...

dim

signature(x = "matrix.csc"): ...

t

signature(x = "matrix.csc"): ...

See also

matrix.csr-class

Examples

  cscM <- as.matrix.csc(as(diag(4:1), "matrix.csr"))
  cscM
#> Sparse matrix of class "matrix.csc" {use 'str(.)' to see the inner structure}:
#>      [,1] [,2] [,3] [,4]
#> [1,]    4    .    .    .
#> [2,]    .    3    .    .
#> [3,]    .    .    2    .
#> [4,]    .    .    .    1
  str(cscM)
#> Formal class 'matrix.csc' [package "SparseM"] with 4 slots
#>   ..@ ra       : num [1:4] 4 3 2 1
#>   ..@ ja       : int [1:4] 1 2 3 4
#>   ..@ ia       : int [1:5] 1 2 3 4 5
#>   ..@ dimension: int [1:2] 4 4
  stopifnot(identical(dim(cscM), c(4L, 4L)))