hi Arun, Thanks for this. This solution works great.
Knid Regards Anup On Sun, Jul 14, 2013 at 8:07 PM, arun <smartpink...@yahoo.com> wrote: > Hi, > You could try this: (if I understand it correctly) > dat1<- read.table(text=" > year id var ans > 2010 1 1 1 > 2010 2 0 0 > 2010 1 0 1 > 2010 1 0 1 > 2011 2 1 1 > 2011 2 0 1 > 2011 1 0 0 > 2011 1 0 0 > ",sep="",header=TRUE,stringsAsFactors=FALSE) > > dat1$newres<-with(dat1,ave(var,id,year,FUN=function(x) any(x==1)*1)) > dat1 > # year id var ans newres > #1 2010 1 1 1 1 > #2 2010 2 0 0 0 > #3 2010 1 0 1 1 > #4 2010 1 0 1 1 > #5 2011 2 1 1 1 > #6 2011 2 0 1 1 > #7 2011 1 0 0 0 > #8 2011 1 0 0 0 > > A.K. > > ----- Original Message ----- > From: Anup Nandialath <anupme...@gmail.com> > To: r-help@r-project.org > Cc: > Sent: Sunday, July 14, 2013 7:30 AM > Subject: [R] creating dummy variables based on conditions > > Hello everyone, > > I have a dataset which includes the first three variables from the demo > data below (year, id and var). I need to create the new variable ans as > follows > > If var=1, then for each year (where var=1), i need to create a new dummy > ans which takes the value of 1 for all corresponding id's where an instance > of one was recorded. Sample data with the output is shown below. > > year id var ans > [1,] 2010 1 1 1 > [2,] 2010 2 0 0 > [3,] 2010 1 0 1 > [4,] 2010 1 0 1 > [5,] 2011 2 1 1 > [6,] 2011 2 0 1 > [7,] 2011 1 0 0 > [8,] 2011 1 0 0 > > Any help on how to achieve this is much appreciated. > > Thanks > Anup > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
