[R] Need advise in grab the line number of sorted list in R

Karl Ove Hufthammer Karl.Hufthammer at math.uib.no
Mon Jun 2 15:54:04 CEST 2008

Jason Lee:

> I have a data frame which format is like below:-
> X     Y     Z
> 131 22.2 3.4   4.4
> 150  20.0 12.2 4.5
> etc...
> And I have sorted the data frame. However, I would like to grab one of
> these elements in the data frame. Also, i would like to number these rows
> so that when i grab a particular line let say 150, it is able to return me
> the position of the row rather than the "150". Let say in this example,
> when i grab a value of 150, it gives me 2 rather than 150.

I'm not sure I understand what you're trying to do. Could you try to explain
using code example of how you 'grab' elements?

One solution could perhaps be to simple renumber the data frame. If the data
frame is named 'dat', you can do it simply by

row.names(dat) = NULL

Karl Ove Hufthammer

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