File-Backed Matrix Class with Convenient Read and Write Access
Interface for working with large matrices stored in files, not in computer memory. Supports multiple non-character data types (double, integer, logical and raw) of various sizes (e.g. 8 and 4 byte real values). Access to parts of the matrix is done by indexing (e.g. fm[,1]), exactly as with usual R matrices. Supports very large matrices. Tested on multi-terabyte matrices. Allows for more than 2^32 rows or columns. Allows for quick addition of extra columns to a filematrix. Cross-platform as the package has R code only.
A new file.matrix object can be created with fm.create
and fm.create.from.matrix. Existing file.matrix
files can be opened with fm.open.
Once a file.matrix is created or opened it can be accessed
as a regular matrix object in R.
All changes to file.matrix object are written to the data files
without extra buffering.
See fm.create and '>filematrix
for reference.
Run browseVignettes("filematrix") for the list of vignettes.