formatSparseM {Matrix}  R Documentation 
Utilities for formatting sparse numeric matrices in a flexible way.
These functions are used by the format
and print
methods for sparse matrices and can be applied as well to standard R
matrices. Note that all arguments but the first are optional.
formatSparseM()
is the main “workhorse” of
formatSpMatrix
, the format
method for sparse
matrices.
.formatSparseSimple()
is a simple helper function, also dealing
with (short/empty) column names construction.
formatSparseM(x, zero.print = ".", align = c("fancy", "right"),
m = as(x,"matrix"), asLogical=NULL, uniDiag=NULL,
digits=NULL, cx, iN0, dn = dimnames(m))
.formatSparseSimple(m, asLogical=FALSE, digits=NULL,
col.names, note.dropping.colnames = TRUE,
dn=dimnames(m))
x 
an R object inheriting from class 
zero.print 
character which should be used for
structural zeroes. The default 
align 
a string specifying how the 
m 
(optional) a (standard R) 
asLogical 
should the matrix be formatted as a logical matrix
(or rather as a numeric one); mostly for 
uniDiag 
logical indicating if the diagonal entries of a sparse
unit triangular or unitdiagonal matrix should be formatted as

digits 
significant digits to use for printing, see

cx 
(optional) character matrix; a formatted version of 
iN0 
(optional) integer vector, specifying the location of the
nonzeroes of 
col.names, note.dropping.colnames 
see 
dn 

a character matrix like cx
, where the zeros have been replaced
with (padded versions of) zero.print
.
As this is a dense matrix, do not use these functions for
really large (really) sparse matrices!
Martin Maechler
formatSpMatrix
which calls formatSparseM()
and is
the format
method for sparse matrices.
printSpMatrix
which is used by the (typically
implicitly called) show
and print
methods
for sparse matrices.
m < suppressWarnings(matrix(c(0, 3.2, 0,0, 11,0,0,0,0,7,0), 4,9))
fm < formatSparseM(m)
noquote(fm)
## nice, but this is nicer {with "units" vertically aligned}:
print(fm, quote=FALSE, right=TRUE)
## and "the same" as :
Matrix(m)
## align = "right" is cheaper > the "." are not aligned:
noquote(f2 < formatSparseM(m,align="r"))
stopifnot(f2 == fm  m == 0, dim(f2) == dim(m),
(f2 == ".") == (m == 0))