elementary operations, like taking a power, act elementwise on vectors and matrices. You may use a spectral decomposition to compute powers of a matrix - or a for loop if you are interested in small integer powers.
HTH Giovanni -- __________________________________________________ [ ] [ Giovanni Petris [EMAIL PROTECTED] ] [ Department of Mathematical Sciences ] [ University of Arkansas - Fayetteville, AR 72701 ] [ Ph: (479) 575-6324, 575-8630 (fax) ] [ http://definetti.uark.edu/~gpetris/ ] [__________________________________________________] > Date: Tue, 20 Jan 2004 16:40:07 +0000 > From: Federico Calboli <[EMAIL PROTECTED]> > Sender: [EMAIL PROTECTED] > Organization: > Precedence: list > > Dear All, > > I would like to ask why the zeroeth power of a matrix gives me a matrix > of ones rather than the identity matrix: > > > D<-rbind(c(0,0,0),c(0,0,0),c(0,0,0)) > > D<-as.matrix(D) > > D > [,1] [,2] [,3] > [1,] 0 0 0 > [2,] 0 0 0 > [3,] 0 0 0 > > > D^0 > [,1] [,2] [,3] > [1,] 1 1 1 > [2,] 1 1 1 > [3,] 1 1 1 > > I would have expected the identity matrix here. > > I find the same result with every other square matrix I used. > BTW, I am using R 1.8.1 on Linux Mandrake 9.1 > > Cheers, > > Federico Calboli > -- > > > > ================================= > > Federico C. F. Calboli > > PLEASE NOTE NEW ADDRESS > > Dipartimento di Biologia > Via Selmi 3 > 40126 Bologna > Italy > > tel (+39) 051 209 4187 > fax (+39) 051 251 208 > > f.calboli at ucl.ac.uk > > ______________________________________________ > [EMAIL PROTECTED] mailing list > https://www.stat.math.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://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
