[R] computing ranks in subgroups

[RINNER Heinrich]

Dear R-users!

I am using R 1.0.0 and Windows NT 4.0. I want to compute ranks for the
values of a variable, in several subgroups of a data.frame.
Currently I use:
> #example:
> x <- data.frame(group=c("A","A","B","A","B","B","A"),
val=c(10,3,9,3,5,1,7))
> x
  group val
1     A  10
2     A   3
3     B   9
4     A   3
5     B   5
6     B   1
7     A   7
> x.new<-x[order(x$group),  ]
> x.new$valgroupranks <- unlist(tapply(x.new$val, x.new$group, rank))
> x.new
  group val valgroupranks
1     A  10           4.0
2     A   3           1.5
4     A   3           1.5
7     A   7           3.0
3     B   9           3.0
5     B   5           2.0
6     B   1           1.0
> 
This seems to work, but I wonder if there is a more "natural" (simple?) way
to do that?

Heinrich..
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