Hello R User
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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