R: Formatting Sparse Numeric Matrices Utilities

formatSparseM {Matrix}

R Documentation

Formatting Sparse Numeric Matrices Utilities

Description

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.

Usage

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))

Arguments

`x`	an R object inheriting from class `sparseMatrix`.
`zero.print`	character which should be used for structural zeroes. The default `"."` may occasionally be replaced by `" "` (blank); using `"0"` would look almost like `print()`ing of non-sparse matrices.
`align`	a string specifying how the `zero.print` codes should be aligned, see `formatSpMatrix`.
`m`	(optional) a (standard R) `matrix` version of `x`.
`asLogical`	should the matrix be formatted as a logical matrix (or rather as a numeric one); mostly for `formatSparseM()`.
`uniDiag`	logical indicating if the diagonal entries of a sparse unit triangular or unit-diagonal matrix should be formatted as `"I"` instead of `"1"` (to emphasize that the 1's are “structural”).
`digits`	significant digits to use for printing, see `print.default`.
`cx`	(optional) character matrix; a formatted version of `x`, still with strings such as `"0.00"` for the zeros.
`iN0`	(optional) integer vector, specifying the location of the non-zeroes of `x`.
`col.names`, `note.dropping.colnames`	see `formatSpMatrix`.
`dn`	`dimnames` to be used; a list (of length two) with row and column names (or `NULL`).

Value

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!

Author(s)

Martin Maechler

Examples

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))

[Package Matrix version 1.7-1 Index]