size

0th

Percentile

Gets or sets the size of a permutation

The ‘size’ of a permutation is the cardinality of the set for which it is a bijection.

Keywords
symbmath
Usage
size(x)
addcols(M,n)
# S3 method for word
size(x)
# S3 method for cycle
size(x)
# S3 method for word
size(x) <- value
# S3 method for cycle
size(x) <- value
Arguments
x

A permutation object

M

A matrix that may be coerced to a word

n,value

the size to set to, an integer

Details

For a word object, the size is equal to the number of columns. For a cycle object, it is equal to the largest element of any cycle.

Function addcols() is a low-level function that operates on, and returns, a matrix. It just adds columns to the right of M, with values equal to their column numbers, thus corresponding to fixed elements. The resulting matrix has n columns. This function cannot remove columns, so if n<ncol(M) an error is returned.

Setting functions cannot decrease the size of a permutation; use trim() for this.

It is meaningless to change the size of a cycle object. Trying to do so will result in an error. But you can coerce cycle objects to word form, and change the size of that.

See Also

fixed

Aliases
  • size
  • size.cycle
  • size<-.cycle
  • size.word
  • size<-
  • size<-.word
  • addcols
Examples
# NOT RUN {
x <- rperm(10,8)
size(x)
size(x) <- 15

size(as.cycle(1:5) + as.cycle(100:101))

size(id)
# }
Documentation reproduced from package permutations, version 1.0-5, License: GPL-2

Community examples

Looks like there are no examples yet.