Dear Mark, I believe that your solution won't work if there are more than two matrices to sum.
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 Marc Schwartz > Sent: Wednesday, March 16, 2005 11:30 AM > To: Vicky Landsman > Cc: R-Help > Subject: Re: [R] Summing up matrices in a list > > On Wed, 2005-03-16 at 18:21 +0200, Vicky Landsman wrote: > > Dear all, > > I think that my question is very simple but I failed to solve it. > > I have a list which elements are matrices like this: > > > > >mylist > > [[1]] > > [,1] [,2] [,3] > > [1,] 1 3 5 > > [2,] 2 4 6 > > > > [[2]] > > [,1] [,2] [,3] > > [1,] 7 9 11 > > [2,] 8 10 12 > > > > I'd like to create a matrix M<-mylist[[1]]+mylist[[2]] > > [,1] [,2] [,3] > > [1,] 8 12 16 > > [2,] 10 14 18 > > > > Is there a way to create M without looping? > > Thanks a lot, > > > > do.call("+", mylist) > [,1] [,2] [,3] > [1,] 8 12 16 > [2,] 10 14 18 > > See ?do.call for more information. > > HTH, > > Marc Schwartz > > ______________________________________________ > [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
