[R] Help with apply and split...

I'm trying to drop all rows except for the ones with the most recent year. So I split the data frame by NPERMNO and keep just the last record of all groups. datg=t(sapply(split(datgic, datgic$NPERMNO, drop=TRUE), function(x){return( x[nrow(x),] )})) I get something like this... GVKEY

Re: [R] Help with apply and split...

datg=t(sapply(split(datgic, datgic$NPERMNO, drop=TRUE), function(x){return( x[nrow(x),] )})) I get something like this... GVKEY NPERMNO GIC year 10001 12994 10001 55102010 2007 10002 19049 10002 40101015 2007 10009 16739 10009 40101010 1999 Has this been made