Hi, I was wondering if there is a more efficient way of handling the following method of creating a lagged value in a data frame without using the recursive 'for(i in 1:n)' loop and without using as.ts
#Steps to creating a lag variable in a data frame 'my.dat.fr' # with 275 columns, 2400 rows of numbers and factors . The #variable x is a factor of #with five different levels the way i am creating the variable now is: attach(my.dat.fr) #my.dat.fr contains a variable 'x', i want to create #lagged variables #of this without using as.ts(). Is #there a more effient way of doing this than#below and #without using a recursive loop such as #for( i in 1:obs)x.lag[i]= x[(i-1)] 1.here is the way i am doing the lag now x=c(3,2,3,2,1,1,1,2,1,2,1,3...1) obs=length(x) x.nolag=x[2:obs] x.lag1=x[1:(obs-1)] my.new=cbind(x.nolag,x.lag1) #since my data frame must line up my orginal x values to other columns I also # add the following x.fill= cbind(0,0) # as named the above cell lines up my factor to other factors in my data frame, #since I had chopped off the first x observation to create x above (ie x[2:obs]) #then finally my.dat.fr=rbind(x.fill, my.new) my.dat.fr #Is there a easier way to create a lag variable and install in my data frame? #thankyou in advance, Sri ______________________________________________ [EMAIL PROTECTED] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
