Convert a sparse matrix to a dense matrix in a block-wise fashion

Usage

sparseToDenseMatrix(
  mat,
  blockwise = TRUE,
  by.row = TRUE,
  by.col = FALSE,
  chunk.size = 100000,
  parallel = FALSE,
  cores = 2
)

Arguments

mat: Input sparse matrix
blockwise: Whether to do the coercion in a block-wise manner
by.row: Whether to chunk in a row-wise fashion
by.col: Whether to chunk in a column-wise fashion
chunk.size: The size of the chunks to use for coercion
parallel: Whether to perform the coercion in parallel
cores: The number of cores to use in the parallel coercion

Value

A dense matrix of the same dimensions as the input

Examples

# make a sparse binary matrix
library(Matrix)
m <- 100
n <- 1000
mat <- round(matrix(runif(m * n), m, n))
mat.sparse <- Matrix(mat, sparse = TRUE)

# coerce back
mat.dense <- sparseToDenseMatrix(mat.sparse, chunk.size = 10)
#> Using chunk size: 10
#> Breaking into row chunks.

# make sure they are the same dimensions
dim(mat) == dim(mat.dense)
#> [1] TRUE TRUE

# make sure they are the same numerically
all(mat == mat.dense)
#> [1] TRUE