Here is an additional way: model.matrix(~ factor(a) - 1)
On 9/1/06, Gabor Grothendieck <[EMAIL PROTECTED]> wrote:
Try using outer: outer(1:3, a, "==")+0 On 8/31/06, z s <[EMAIL PROTECTED]> wrote: > Hi, > > I am trying to convert a variable a = sample(1:3,100,rep = T) represents choices into a 3X100 dummy varible b with corresponding element set to 1 otherwise 0. > eg. > > a: 1 3 2 1 2 3 1 1.... > > b: 1 0 0 1 0 0 1 1.. > 0 0 1 0 1 0 0 0... > 0 1 0 0 0 1 0 0... > > Is there something like b[a] =1 existing? I could not figure this out myself. > > > --------------------------------- > Mp3疯狂搜-新歌热歌高速下 > [[alternative HTML version deleted]] > > > > ______________________________________________ > [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 > and provide commented, minimal, self-contained, reproducible code. > > >
______________________________________________ [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 and provide commented, minimal, self-contained, reproducible code.
