Partitions {arrangements} | R Documentation |
This function returns a Partitions iterator for iterating
partitions of an non-negative integer n
into k
parts or parts of any sizes.
The iterator allows users to fetch the next partition(s) via the getnext()
method.
Partitions ipartitions(n, k = NULL, distinct = FALSE, descending = FALSE, skip = NULL)
n |
an non-negative integer to be partitioned |
k |
number of parts |
distinct |
an logical to restrict distinct values |
descending |
an logical to use reversed lexicographical order |
skip |
the number of partitions skipped |
An object of class R6ClassGenerator
of length 25.
The Partitions
class can be initialized by using the convenient wrapper ipartitions
or
Partitions$new(n, k = NULL, descending = FALSE)
getnext(d = 1L, layout = NULL, drop = NULL) collect(layout = "row") reset()
number of fetched arrangements
if "row", "column" or "list" is specified, the returned value would be a "row-major" matrix, a "column-major" matrix or a list respectively
vectorize a matrix or unlist a list
partitions for generating all partitions and npartitions to calculate number of partitions
ipart <- ipartitions(10) ipart$getnext() ipart$getnext(2) ipart$getnext(layout = "column", drop = FALSE) # collect remaining partitions ipart$collect() library(foreach) foreach(x = ipartitions(6, 2), .combine=c) %do% { prod(x) }