Description Details Note Author(s) See Also
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.
Due to lack of 64 bit integer data type in R, the package uses double values for calculation of indices. The precision of double data type is sufficient for indexing matrices up to 8,192 terabytes in size.
Andrey A Shabalin andrey.shabalin@gmail.com
See fm.create
and filematrix
for reference.
Run browseVignettes("filematrix")
for the list of vignettes.
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.