Become an expert in R — Interactive courses, Cheat Sheets, certificates and more!
Get Started for Free

vt

Virtual transpose


Description

The vt generic does a matrix or array transpose by modifying virtual attributes rather than by physically copying matrix elements.

Usage

vt(x, ...)
## S3 method for class 'ff'
vt(x, ...)
## Default S3 method:
vt(x, ...)
## S3 method for class 'ff'
t(x)

Arguments

x

an ff or ram object

...

further arguments (not used)

Details

The vt.ff method does transpose through reversing dim.ff and dimorder. The vt.default method is a wrapper to the standard transpose t.
The t.ff method creates a transposed clone.
If x has a virtual window vw defined, vt.ff returns an ff object with a transposed virtual window, the t.ff method return a transposed clone of the virtual window content only.

Value

an object that behaves like a transposed matrix

Author(s)

Jens Oehlschlägel

See Also

Examples

x <- ff(1:20, dim=c(4,5))
  x
  vt(x)
  y <- t(x)
  y
  vw(x) <- cbind(c(1,3,0),c(1,4,0))
  x
  vt(x)
  y <- t(x)
  y
  rm(x,y); gc()

ff

Memory-Efficient Storage of Large Data on Disk and Fast Access Functions

v4.0.4
GPL-2 | GPL-3 | file LICENSE
Authors
Daniel Adler [aut], Christian Gläser [aut], Oleg Nenadic [aut], Jens Oehlschlägel [aut, cre], Martijn Schuemie [aut], Walter Zucchini [aut]
Initial release
2020-10-13

We don't support your browser anymore

Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.