I have a matrix of claims at year1 that I get simply by claims<-read.csv(file="Claims.csv") qq1<-claims[claims$Year=="Y1",]
I have MemberID and ProviderID for every claim in qq1 both are integers An example for the type of questions that I want to answer is how many times ProviderID number 345 appears together with MemberID 23 in the table qq1 In order to answer these questions for every possible ProviderId and every possible MemberID I would like to have a matrix that has first column as memberID when every memberID in qq1 appears only once and columns that have number of appearance of ProviderID==i for every i that has sum(qq1$ProviderID==i)>0 My question is if there is a simple way to do it in R Thanks in Advance Uri -- View this message in context: http://r.789695.n4.nabble.com/How-to-build-a-matrix-of-number-of-appearance-tp3643248p3643248.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.