Dear Saroj, This isn't a solution to your general question about ..., but makeContrasts in limma already accepts character vector arguments: x <- c("a-b","b-c") makeContrasts(contrasts=x, levels=c("a","b","c")) Best wishes Gordon > Date: Wed, 03 Jun 2009 09:44:44 -0400 > From: Saroj K Mohapatra <saroj at="" vt.edu=""> > Subject: Re: [BioC] variable as argument to makeContrasts (limma) > To: Martin Morgan <mtmorgan at="" fhcrc.org=""> > Cc: Georg Otto <georg.otto at="" tuebingen.mpg.de="">, > bioconductor at stat.math.ethz.ch > > Martin Morgan wrote: >> >> One way is to aim for >> >> do.call(makeConstrasts, myargs) >> >> where the 'myargs' is a list that you can construct any way you like, >> e.g., >> >> myargs = list("B-A", "C-B", "C-A", levels=design) >> do.call(makeContrasts, myargs) >> > Perfect! > > Saroj > > > >> Martin >> >>>> >>>> So my question is: how can I make this work, and - more generally - how >>>> can I replace the "..." option in a function by a variable? >>>> >>>> Thanks, >>>> >>>> Georg