[R] How can I eliminate a loop over a data.table?

2013-03-19 Thread Matteo Richiardi
I've two data.tables as shown below: *** N = 10 A.DT - data.table(a1 = c(rnorm(N,0,1)), a2 = NA)) B.DT - data.table(b1 = c(rnorm(N,0,1)), b2 = 1:N) setkey(A.DT,a1) setkey(B.DT,b1) *** I tried to change my previous data.frame implementation to a data.table implementation by changing the for-loop

Re: [R] How can I eliminate a loop over a data.table?

2013-03-19 Thread Blaser Nello
], A.DT[nrow(A.DT):1, a2]), na.last=FALSE)) -Original Message- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Matteo Richiardi Sent: Dienstag, 19. März 2013 08:24 To: r-help@r-project.org Subject: [R] How can I eliminate a loop over

[R] How can I eliminate a loop over a data.table?

2013-03-18 Thread Matteo Richiardi
I've two data.tables as shown below: *** N = 10 A.DT - data.table(a1 = c(rnorm(N,0,1)), a2 = NA)) B.DT - data.table(b1 = c(rnorm(N,0,1)), b2 = 1:N) setkey(A.DT,a1) setkey(B.DT,b1) *** I tried to change my previous data.frame implementation to a data.table implementation by changing the for-loop