[BioC] Filtering by fold change

[peter robinson]

Dear List,

I guess this is a pretty basic question, but I have not found an answer in the 
archives. I would like to take a matrix representing m hybridizations and 
sort it to extract the 2000 genes with the maximal fold change as a 
preliminary step of a further analysis. Is it possible to use the geneFilter 
to extract a fixed number of the "top" genes as above rather than genes 
satisfying some fixed criterion?

Thanks

Peter