I think it will depend on how you plan to use the data. Again in my opinion, I think the simplest most natural storage structure in the context of R would be a nested list:
mydat <- list( list(contacts=c(3,4), ncon=2), list(contacts=c(1,3,4), ncon=3), list(contacts=c(4,2,1), ncon=3), list(contacts=1, ncon=1) ) ## if the id values are not sequential integers, then you would also need names(mydat) <- {whatever the id values are} Depending on subsequent processing, it might not be necessary to store the number of contacts, because it can easily be calculated whenever needed. In which case the structure could be simpler: mydat <- list( c(3,4), c(1,3,4), c(4,2,1), 1 ) names(mydat) <- {whatever the id values are} Even though a data frame can be used, as Duncan and arun have shown, a data frame does not seem natural to me, given that the number of contacts is not the same for all ids. It may also depend on where the data is coming from and how much there is of it. -Don -- Don MacQueen Lawrence Livermore National Laboratory 7000 East Ave., L-627 Livermore, CA 94550 925-423-1062 On 5/10/14 4:46 AM, "Ragia Ibrahim" <ragi...@hotmail.com> wrote: >Dear Group, >I have data like the following > >id contacts_list number of contacts >--------------------------------------------------- >1 3 4 2 >2 1 3 4 3 >3 4 2 1 3 >4 1 1 >------------------------------------------------------ > > >can you kindly please sugest a data type in R to use for it? >i thought about data frame that consists of a list element. but lists >are not in the same length, any solutions? >thanks in advance >RAE > > [[alternative HTML version deleted]] > >______________________________________________ >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. ______________________________________________ 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.