Hi Trying to produce a histogram with the same line type for each sample but it produces the error below: > hist(data.lumi,col=cols,lty=1) Error in matplot(all.x, all.y, ylab = ylab, xlab = xlab, type = type, : formal argument "lty" matched by multiple actual arguments > sessionInfo() R version 2.6.0 Under development (unstable) (2007-08-11 r42469) i386-pc-mingw32 locale: LC_COLLATE=English_New Zealand.1252;LC_CTYPE=English_New Zealand.1252;LC_MONETARY=English_New Zealand.1252;LC_NUMERIC=C;LC_TIME=English_New Zealand.1252 attached base packages: [1] tools stats graphics grDevices utils datasets methods [8] base other attached packages: [1] lumiRatV1_1.3.0 lumi_1.3.29 annotate_1.15.3 [4] AnnotationDbi_0.0.88 RSQLite_0.6-0 DBI_0.2-3 [7] mgcv_1.3-25 affy_1.15.7 preprocessCore_0.99.12 [10] affyio_1.5.8 Biobase_1.15.26 This has previously worked for me, so has something changed in the devel package that I need to alter my script? Cheers Alice P Think before you print