duplicate <- c(0, diff(a[,"col1"]) == 0)
Peter Ehlers On 2012-07-25 13:05, Jeff wrote:
I'm trying to find duplicate values in a column of a data frame. For example, dataframe (a) below has two 3's. I would like to mark each value of each row as either not being a duplicate of the one before (0), or as a duplicate (1) - for example, as in dataframe (b). In SPSS, I would simply compare each value to it's "lagged" value, but I can't figure out how to do this with R. Can someone point me in the right direction? Thanks a <- data.frame( col1 = c(1,2,3,3,4)) b <- data.frame( col1 = c(1,2,3,3,4), duplicate = c(0,0,0,1,0)) ______________________________________________ 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.