On 09/06/2010 03:00 PM, rajeshj at cse.iitm.ac.in wrote: > > Hi, > > I have a vector who contents should look like this, > > "c" "d" NULL "e" "f" etc > or > 4 5 6 NULL 7 8 9 > > how can I represent the null value? Hi rajesh, For character vectors, "" will probably suffice, but for numbers, you are probably stuck with NA. Jim