rle: Run Length Encoding

In robertzk/monadicbase: The R Base Package

Description

Compute the lengths and values of runs of equal values in a vector – or the reverse operation.

Usage

rle(x)
inverse.rle(x, ...)

## S3 method for class 'rle'
print(x, digits = getOption("digits"), prefix = "", ...)

Arguments

x	a vector (atomic, not a list) for rle(); an object of class "rle" for inverse.rle().
...	further arguments; ignored here.
digits	number of significant digits for printing, see print.default.
prefix	character string, prepended to each printed line.

Details

‘vector’ is used in the sense of is.vector.

Missing values are regarded as unequal to the previous value, even if that is also missing.

inverse.rle() is the inverse function of rle(), reconstructing x from the runs.

Value

rle() returns an object of class "rle" which is a list with components:

lengths	an integer vector containing the length of each run.
values	a vector of the same length as lengths with the corresponding values.

inverse.rle() returns an atomic vector.

Examples

x <- rev(rep(6:10, 1:5))
rle(x)
## lengths [1:5]  5 4 3 2 1
## values  [1:5] 10 9 8 7 6

z <- c(TRUE, TRUE, FALSE, FALSE, TRUE, FALSE, TRUE, TRUE, TRUE)
rle(z)
rle(as.character(z))
print(rle(z), prefix = "..| ")

N <- integer(0)
stopifnot(x == inverse.rle(rle(x)),
          identical(N, inverse.rle(rle(N))),
          z == inverse.rle(rle(z)))

robertzk/monadicbase documentation built on May 27, 2019, 10:35 a.m.