Dear All, I've recently gotten to grips with aCGH analysis using snapCGH and aCGH packages. All is now going well, except in aCGH (Jane Fridlyand) I'm unable to get the acgh.process command to run with duplicate removal = TRUE. It works if dupRemoval is set to False This is what I get: #> ex.acgh<-aCGH.process(ex.acgh, chrom.remove.threshold=23, prop.missing=0.25, sample.quality.threshold=0.4, unmapScreen=T, dupRemove=TRUE) Averaging duplicated clones CTB-102E19 4656 4657 Error in `[<-.data.frame`(`*tmp*`, ind1[j], , drop = FALSE, value = c(- 0.156355155, : unused argument(s) (drop = FALSE) #> Would be grateful if anyone has any tips on how to handle duplicate clones in aCGH. Thanks very much. Ian