[R] colnames and get means for the columns with the "same" names

[Weiwei Shi]

hi,
I have a conversion table for colnames like this:
          Probe_ID HUMAN_LLID
1  AF106325_PROBE1       7052
2 NM_019386_PROBE1       7052
3 NM_012907_PROBE1        339
4  AW917796_PROBE1      84196
5    L27651_PROBE1      10864

The Probe_ID contains a list of colnames for another data.frame, say x1.
I need to convert such colnames to another ID's system, HUMAN_LLID by
using the table. The colnames of x1 with the same names (in
HUMAN_LLID) need to be averaged. Is there a good way to do it?

I also put this question in bioconductor since I believe it might be
solved by some package.

thanks.

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

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