[R] what fun I need to put in this "tapply"

[Weiwei Shi]

Hi,
I happened to need generate the following
> t1
  V1 V2 count count2
1  1 11     2      3
2  1 12     2      2
3  2 11     1      3
4  3 13     3      1
5  3 11     3      3
6  3 12     3      2

from
  V1 V2
1  1 11
2  1 12
3  2 11
4  3 13
5  3 11
6  3 12

I am wondering what function of funx I need to put into
tapply(t1[,2], t1[,2] funx)

to get that?

If I use length, I probabaly need to do merge by myself. Is there a better way?

thanks.


-- 
Weiwei Shi, Ph.D
Research Scientist
GeneGO, Inc.

"Did you always know?"
"No, I did not. But I believed..."
---Matrix III