Hi Diane, Does this do what you want ?
listParts <- function(n) { # Generates a list of lists representing the partitions # of an integer n require(partitions) x <- 1:n apply(setparts(n), 2, function(pp) tapply(x, pp, function(xx) list(xx))) } Michael On 12 November 2010 21:15, Diana Tichy <d.ti...@mathematik.uni-wuerzburg.de> wrote: > Hello Michael > once again. Now I can use print.partition which tells me, how to generate, > e.g., all possible 5 partitions of {1,2,3}. But this generation is still > complicated. Does there already exist a function doing that for me, e.g. > returns a list, where the first element contains the one-elemnt partion, the > second to fourth the three 2-element-partions and the fifth the 3-element > partition? > Do you know or is it my job to implement this by myself (o.k. but > time-consuming ..) > > Best wishes > Diana > > Am 12.11.2010 10:32, schrieb Michael Bedward: >> >> Hi Diana, >> >> Have a look at the setparts function in the partitions package. >> >> Michael >> >> On 12 November 2010 20:03, Diana<d.ti...@mathematik.uni-wuerzburg.de> >> wrote: >>> >>> Hi >>> >>> I am new on this forum. I am searching for a function in R which provides >>> all partitions of a set, say for the set >>> {1,2,3} >>> you get >>> {{1,2,3}} >>> {1,{2,3}} >>> {2,{1,3}} >>> {3,{1,2}} >>> {{1},{2},{3}} >>> . The number of partitions of a set is given by Bellsche`s number. The >>> number of possibilities of length (this is the number of subsets included >>> in >>> the partition) of the partition is given by the partition function. >>> But I need a list containg all possible partitions of an index set >>> {1,...,d}, d arbitrary. >>> >>> I have already looked at the FAQs but I did not found. Sorry. >>> >>> Can anybody help me? >>> >>> Thanks a lot! >>> Diana Tichy >>> -- >>> View this message in context: >>> http://r.789695.n4.nabble.com/Partition-of-a-set-tp3039291p3039291.html >>> Sent from the R help mailing list archive at Nabble.com. >>> >>> ______________________________________________ >>> R-help@r-project.org mailing list >>> https://stat.ethz.ch/mailman/listinfo/r-help >>> PLEASE do read the posting guide >>> http://www.R-project.org/posting-guide.html >>> and provide commented, minimal, self-contained, reproducible code. >>> > > -- > Diana Tichy (geb. Stöhr) > Lehrstuhl für Statistik > Institut für Mathematik > Universität Würzburg > Am Hubland > 97074 Würzburg > Raum R110, Mathematikgebäude > Tel.: 0931-31 85027 > d.ti...@mathematik.uni-wuerzburg.de > http://statistik.mathematik.uni-wuerzburg.de/~tichy > > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.