[R] misleading output after ordering data frame

[Thomas Lumley]

On Mon, 8 Nov 2004, bogdan romocea wrote:

> My problem is that even though the data frame is ordered as
> requested, the old row numbers are preserved. For example:
>
> * Before sorting:
>> d[1:3,]
>      Date   Amt
> 1 5-Nov-04 87.07
> 2 4-Nov-04 85.80
> 3 3-Nov-04 82.90
>
> * After sorting:
>> d[1:3,]
>         Date   Amt
> 500 12-Nov-02 84.23
> 499 13-Nov-02 85.05
> 498 14-Nov-02 84.95
>
> Is there a way to update the row numbers as well? It's not that
> important, but I find it a bit confusing.
>

This is an important feature of R: the row names of a data frame stay 
fixed under subsetting or reordering.

You can change the rownames with eg

    rownames(d)<-1:nrow(d)

if you want to.


 	-thomas