rle: Run Length Encoding

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 rle
print(x, digits = getOption("digits"), prefix = "", …)

Arguments

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.

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.

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.

Examples

Run this code

# NOT RUN {
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)))
# }