Full_Name: J. R. M. Hosking Version: 1.5 OS: Win2000 Submission from: (NULL) (198.81.209.17) Documentation for pmax says "`attributes' (such as `names' or `dim') are transferred from the first argument (if applicable)". But:> a<-matrix(c(1,2,3,-1,-2,3),2,3,dimnames=list(c("A","B"),NULL)) > a[,1] [,2] [,3] A 1 3 -2 B 2 -1 3> pmax(a,0)[,1] [,2] [,3] [1,] 1 3 0 [2,] 2 0 3 The row names have been lost. This doesn't happen with column names, and it doesn't happen in S-plus, so it looks like a bug.