externalFormats {Matrix} | R Documentation |
Read matrices stored in the Harwell-Boeing or MatrixMarket formats or write sparseMatrix objects to one of these formats.
readHB(file) readMM(file) writeHB(obj, file, ...) writeMM(obj, file, ...)
obj |
a real sparse matrix |
file |
for writeHB and writeMM - the name of the
file to be written. For readHB and readMM
the name of the file to read, as a character scalar.
The names of files storing matrices in the Harwell-Boeing format
usually end in ".rua" or ".rsa" . Those storing
matrices in the MatrixMarket format usually end in {".mtx"}.
Alternatively, readHB accepts a connection object. |
... |
optional additional arguments. Currently none are used in any methods. |
The readHB
and readMM
functions return an object that
inherits from the "Matrix"
class. Methods for the
writeHB
and writeMM
generic functions usually return
NULL
and, as a side effect, the matrix obj
is written to
file
in the Harwell-Boeing format (writeHB)
or the MatrixMarket format (writeMM).
http://math.nist.gov/MatrixMarket
http://www.cise.ufl.edu/research/sparse/matrices
str(pores <- readMM(system.file("external/pores_1.mtx", package = "Matrix"))) str(utm <- readHB(system.file("external/utm300.rua", package = "Matrix"))) str(lundA <- readMM(system.file("external/lund_a.mtx", package = "Matrix"))) str(lundA <- readHB(system.file("external/lund_a.rsa", package = "Matrix"))) ## Not run: ## NOTE: The following examples take quite some time ## ---- even on a fast internet connection: str(sm <- readHB(gzcon(url("http://www.cise.ufl.edu/research/sparse/HBformat/Boeing/msc00726.rsa.gz")))) str(jgl009 <- readMM(gzcon(url("ftp://math.nist.gov/pub/MatrixMarket2/Harwell-Boeing/counterx/jgl009.mtx.gz")))) ## End(Not run) data(KNex) writeHB(KNex$mm, "mmHB.rua") writeMM(KNex$mm, "mmMM.mtx")