Hi, folks, Please let me address the problem by the following codes:
first=c('u','b','e','k','j','c','u','f','c','e') second=c('usa','Brazil','England','Korea','Japan','China','usa','France','China','England') third=1:10 data=data.frame(first,second,third) ## You may understand values in the first column are the unique codes for those in the second column. ####So 'u' is only for usa. Replicate values appear the same rows for the first and second columns. ### Now I want to delete replicate rows with the same values in first (sceond) rows ####and sum up values in the third column for the same values. mm=melt(data,id='first') sum=cast(mm,first~variable,sum) ### This does not work. >< But the expected dataframe is like this: 1 u third 8 2 b third 2 3 e third 13 4 k third 4 5 j third 5 6 c third 15 8 f third 8 Thanks in advance. Yi [[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.