nkpartitions {blockmodeling} | R Documentation |
The function nkpartitions
lists all possible partitions of n objects in to k clusters. The function nkpar
only gives the number of such partitions.
nkpartitions(n, k, exact = TRUE, print = FALSE) nkpar(n, k)
n |
Number of units/objects |
k |
Number of clusters/groups |
exact |
Search for partitions with exactly k or at most k clusters |
print |
print results as they are found? |
The matrix or number of possible partitions.
Chris Andrews
n<-8 #if larger, the number of partitions increases dramaticaly, #as does if we increase the number of clusters net<-matrix(NA,ncol=n,nrow=n) clu<-rep(1:2,times=c(3,5)) tclu<-table(clu) net[clu==1,clu==1]<-rnorm(n=tclu[1]*tclu[1],mean=0,sd=1) net[clu==1,clu==2]<-rnorm(n=tclu[1]*tclu[2],mean=4,sd=1) net[clu==2,clu==1]<-rnorm(n=tclu[2]*tclu[1],mean=0,sd=1) net[clu==2,clu==2]<-rnorm(n=tclu[2]*tclu[2],mean=0,sd=1) #computation of criterion function with the correct partition nkpar(n=n, k=length(tclu)) #computing the number of partitions all.par<-nkpartitions(n=n, k=length(tclu)) #forming the partitions all.par<-lapply(apply(all.par,1,list),function(x)x[[1]]) # to make a list out of the matrix res<-check.these.par(M=net,partitions=all.par,approach="ss",blocks="com") plot(res) #we get the original partition