Emslie, Paul [Ctr] <emsliep <at> atac.mil> writes:
>
> I want to take the first row of each unique ID value from a data frame.
> For instance
> > ddTable <-
> data.frame(Id=c(1,1,2,2),name=c("Paul","Joe","Bob","Larry"))
>
> I want a dataset that is
> Id Name
> 1 Paul
> 2 Bob
>
> > unique(ddTable)
> Will give me all 4 rows, and
> > unique(ddTable$Id)
> Will give me c(1,2), but not accompanied by the name column.
ddTable[-which(duplicated(ddTable$Id)), ]
HTH,
Adrian
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