[R] Hello R User

[Eik Vettorazzi]

Hi Bibek,
how about this?

dta<-read.table(textConnection("ID	Time
1	3
1	6
1	7
1	10
1	16
2	12
2	18
2	19
2	25
2	28
2	30"),header=T)

dta$delta<-with(dta,ave(Time,ID,FUN=function(x)c(0,diff(x))))
dta

hth.

Am 14.12.2012 16:51, schrieb bibek sharma:
> Hello R User,
> In the sample data given below, time is recorded for each id
> subsequently. For the analysis, for each id, I would like to set 1st
> recorded time to zero and thereafter find the difference from previous
> time. I.e. for ID==1, I would like to see Time=0,3,1,3,6. This needs
> to be implemented to big data set.
> Any suggestions are much appreciated!
> Thanks,
> Bibek
> 
> ID	Time
> 1	3
> 1	6
> 1	7
> 1	10
> 1	16
> 2	12
> 2	18
> 2	19
> 2	25
> 2	28
> 2	30
> 
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