[R] lost attrubute:names

Hi, when I pick out one element from a matrix, the attribute name is kept, but when more than one elements are extracted, the attribute name lost;   a-matrix(c(1,2,3,11,12,13,45,56,76),ncol=3,dimnames=list(c(),c(c1,c2,c3))) k-a[a[,c3]50,c3] kk-a[a[,c3]60,c3] attributes(k) NULL attributes(kk)

Re: [R] lost attrubute:names

On Thu, 28 Aug 2008, Yuan Jian wrote: Hi, when I pick out one element from a matrix, the attribute name is kept, but when more than one elements are extracted, the attribute name lost; To what attribute 'name' do you refer? I only see 'dim' and 'dimnames' attributes: attributes(a) $dim