Dear Manuel, Although ?sample doesn't specifically describe permuting the rows of a matrix, it does say that "sample(x) generates a random permutation of the elements of x (or 1:x)." Indexing the rows of the matrix by a permutation of 1:x (where x is the number of rows) doesn't seem to be much of a leap.
Regards, John -------------------------------- John Fox Department of Sociology McMaster University Hamilton, Ontario Canada L8S 4M4 905-525-9140x23604 http://socserv.mcmaster.ca/jfox -------------------------------- > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Manuel > López-Ibáñez > Sent: Saturday, April 15, 2006 9:44 AM > To: [email protected] > Subject: Re: [R] permutation of rows of a matrix > > help(sample) does not say anything about randomly permuting > the rows of a matrix M by using M[sample(m,m),]. Perhaps it > could be added as an example of use. > > John Fox wrote: > > Dear Jose, > > > > M[sample(m, m),] will randomly permute the rows of M. [You probably > > could have figured this out via help.search("permutation"), which > > would have led you to sample().] > > > > Regards, > > John > > > > -------------------------------- > > John Fox > > Department of Sociology > > McMaster University > > Hamilton, Ontario > > Canada L8S 4M4 > > 905-525-9140x23604 > > http://socserv.mcmaster.ca/jfox > > -------------------------------- > > > > > >>-----Original Message----- > >>From: [EMAIL PROTECTED] > >>[mailto:[EMAIL PROTECTED] On Behalf Of javargas > >>Sent: Saturday, April 15, 2006 7:53 AM > >>To: [email protected] > >>Subject: [R] permutation of rows of a matrix > >> > >>How can I generate a random permutation between rows of a > matrix M (of > >>m rows and n columns)? > >> > >>Thanks for your help, > >> > >>Jose > >> > >>______________________________________________ > >>[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 > > > > > > ______________________________________________ > > [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 > > > > > ______________________________________________ > LLama Gratis a cualquier PC del Mundo. > Llamadas a fijos y móviles desde 1 céntimo por minuto. > http://es.voice.yahoo.com > > ______________________________________________ > [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 ______________________________________________ [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
