deepcopy: Produces a physical copy of a ``big.matrix''

Description

This is needed to make a duplicate of a big.matrix; currently, it creates a non-shared big.matrix regardless of the nature of the argument, and this will be changed to support additional options.

Usage

deepcopy(x, cols = NULL, type = NULL, separated = NULL, shared = NULL,
         backingfile = NULL, backingpath = NULL, descriptorfile = NULL,
         preserve = TRUE)

Arguments

a big.matrix.

cols

possible subset of columns for the deepcopy, could be numeric, named, or logical.

type

preferably specified, "integer" for example.

separated

use separated column organization of the data instead of column-major organization.

shared

if TRUE, load the object into shared memory.

backingfile

the root name for the file(s) for the cache of x.

backingpath

the path to the directory containing the file backing cache.

descriptorfile

we recommend specifying this for filebacking.

preserve

if this is a filebacked big.matrix, it is preserved, by default, even after the end of the R session unless this option is set to FALSE.

Value

a big.matrix.

Details

This is needed to make a duplicate of a big.matrix, because traditional R syntax would only copy the R object (the pointer to the big.matrix rather than the big.matrix itself). It can also make a copy of only a subset of columns.

Examples

Run this code

x <- as.big.matrix(matrix(1:30, 10, 3))
y <- deepcopy(x, -1)    # Don't include the first column.
x
y
head(x)
head(y)