Hello everyone, my name is Hernando, and I am new to R. I have a little
problem that maybe you can help me with, as I have been looking through the
packages with no success, and it shouldn't be very difficult to solve.
I have a text file containing a list of genes, with expression values for
each along a set of microarray experiments. Ex:

geneID     sample1      sample 2   ....

gene1      45               58        ....

gene1       43              63      .....

gene2      32              21         ....

......        .....           ......        .....

In this list, there are some genes repeated, but with different values (like
in the example). This repetitions come from different probes targeting the
same gene.
What I want is a new text file, but with each gene appearing only once, and
with three possibilities for the expression values of repeated genes:

- Each value (for each column (sample)) is the average of the previous
values (in the example, sample 1 for gene1 should be 44, and 60,5 in sample
2)
- Instead of the average, the median.
- The highest values.

I would prefer the median or the average, but I don't know if getting the
highest values is easier.

I have seen this function: "findLargest" of "genefilter" package, but it
works with probes and I have already converted files (to geneIDs).

I hope you can help me or letting me know any function or package to start
with.

Many thanks


-- 
Hernando Martínez Vergara

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