slam (version 0.1-54)

simple_sparse_array: Simple Sparse Arrays

Description

Data structures and operators for sparse arrays based on a representation by index matrix and value vector.

Usage

simple_sparse_array(i, v, dim = NULL, dimnames = NULL)
as.simple_sparse_array(x)
is.simple_sparse_array(x)
simplify_simple_sparse_array(x, higher = TRUE)
reduce_simple_sparse_array(x, strict = FALSE, order = FALSE)
drop_simple_sparse_array(x)

Arguments

i

Integer matrix of array indices.

v

Vector of values.

dim

Integer vector specifying the size of the dimensions.

dimnames

either NULL or the names for the dimensions. This is a list with one component for each dimension, either NULL or a character vector of the length given by dim for that dimension. The list can be named, and the list names will be used as names for the dimensions. If the list is shorter than the number of dimensions, it is extended by NULL's to the length required.

x

An R object; an object of class simple_sparse_array (see Note).

higher

Option to use the dimensions of the values (see Note).

strict

Option to treat violations of sparse representation as error (see Note).

order

Option to reorder elements (see Note).

Details

simple_sparse_array is a generator for a class of “lightweight” sparse arrays, represented by index matrices and value vectors. Currently, only methods for indexing and coercion are implemented.

See Also

simple_triplet_matrix for sparse matrices.

slam_options for options.

Examples

x <- array(c(1, 0, 0, 2, 0, 0, 0, 3), dim = c(2, 2, 2))
s <- as.simple_sparse_array(x)
identical(x, as.array(s))

simple_sparse_array(matrix(c(1, 3, 1, 3, 1, 3), nrow = 2), c(1, 2))