prv.big.matrix: Tidier display function for big matrix objects

In bigpca: PCA, Transpose and Multicore Functionality for 'big.matrix' Objects

Description

This function prints the first and last columns and rows of a big matrix, and a few more than this if desired. Allows previewing of a big.matrix without overloading the console.

Usage

prv.big.matrix(bigMat, dir = "", rows = 3, cols = 2, name = NULL,
  dat = TRUE, descr = NULL, bck = NULL, mem = FALSE, rcap = "",
  ccap = "", ...)

Arguments

bigMat	the description file, big.matrix object, or big.matrix.descriptor object, anything that can be read by get.big.matrix()
dir	the directory containing the big.matrix backing/description files
rows	integer, number of rows to display
cols	integer, number of columns to display
name	logical, whether to print a name for the matrix
dat	logical, whether to print any of the matrix contents (overrides row/col)
descr	character, optional name of the description file, which if not null will be displayed
bck	character, optional name of the backing file, which if not null will be displayed
mem	logical, whether to display the amount of memory used by the object
rcap	character, caption to display for the rows
ccap	character, caption to display for the columns
...	additional arguments to prv.large (from NCmisc) which displays the end result

Value

Prints to console a compact representation of the bigMat matrix, with the first few rows and columns, and the last row and column. Note that sometimes the initial printing of a big.matrix can take a little while. But subsequently the printout should be almost instantaneous.

See Also

get.big.matrix

Examples

orig.dir <- getwd(); setwd(tempdir()); # move to temporary dir
if(file.exists("test.bck")) { unlink(c("test.bck","test.dsc")) }
bM <- filebacked.big.matrix(20, 50,
       dimnames = list(paste("r",1:20,sep=""), paste("c",1:50,sep="")),
       backingfile = "test.bck",  backingpath = getwd(), descriptorfile = "test.dsc")
bM[1:20,] <- replicate(50,rnorm(20))
prv.big.matrix(bM)
prv.big.matrix(bM,rows=10,cols=4)
rm(bM) 
unlink(c("test.dsc","test.bck"))  # clean up files
setwd(orig.dir)

bigpca documentation built on Nov. 22, 2017, 1:02 a.m.