[R] index after rbind

[Ann Hess]

I am using rbind to concatenate two dataframes, but after the rbind I get
a strange "double" index.

I am using rbind a number of times to make one large dataset.  Is there a
way to prevent the "double" index?  Or is there some other way to
concatenate the data (it looks like merge only works by columns)?

Here is an example of the "double" index.

>numbers<-(1:5)
>letters<-matrix(c("a","b","c","d","e"),5,1)
>data<-data.frame(letters,numbers)
>doubledata<-rbind(data,data)
> doubledata
   letters numbers
1        a       1
2        b       2
3        c       3
4        d       4
5        e       5
11       a       1
22       b       2
33       c       3
44       d       4
55       e       5