The basic “big.matrix” operations for sharing and re-attaching.
describe function returns the information needed by
attach.big.matrix to reference a shared or file-backed
attach.resource functions create a
big.matrix object based on the descriptor information referencing
previously allocated shared-memory or file-backed matrices.
1 2 3
an object as returned by
describe function returns a list of the information needed to
attach to a
A descriptor file is automatically created when a new filebacked
big.matrix is created.
describe returns a list of of the information needed to attach to
attach.big.matrix return a new instance of type
corresponding to a shared-memory or file-backed
Michael J. Kane and John W. Emerson <firstname.lastname@example.org>
big.matrix, or the class documentation
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
# The example is quite silly, as you wouldn't likely do this in a # single R session. But if zdescription were passed to another R session # via SNOW, foreach, or even by a simple file read/write, # then the attach of the second R process would give access to the # same object in memory. Please see the package vignette for real examples. z <- big.matrix(3, 3, type='integer', init=3) z[,] dim(z) z[1,1] <- 2 z[,] zdescription <- describe(z) zdescription y <- attach.big.matrix(zdescription) y[,] y z zz <- attach.resource(zdescription) zz[1,1] <- -100 y[,] z[,]