On 18-Mar-10 20:25:22, seeliger.c...@epamail.epa.gov wrote: >> > I want to be able to rotate a matrix 90 degrees, clockwise. >> > For > example, >> >> mat >> > [,1] [,2] [,3] >> > [,1] 1 2 1 >> > [,2] 3 2 6 >> > [,3] 4 5 3 >> > >> > I want to rotate it, so that it looks like this... >> > [,1] [,2] [,3] >> > [,1] 4 3 1 >> > [,2] 5 2 2 >> > [,3] 3 6 1 >> > >> >> mat >> # [,1] [,2] [,3] >> # [1,] 1 2 1 >> # [2,] 3 2 6 >> # [3,] 4 5 3 >> >> matrix(rev(mat),nrow=3,byrow=TRUE)[(3:1),] >> # [,1] [,2] [,3] >> # [1,] 4 3 1 >> # [2,] 5 2 2 >> # [3,] 3 6 1 >> >> How's that? (But straightforward? Straightbackward, more like). > > One might also work it every bit as straight backward as follows: > z<-matrix(c(1,2,1,3,2,6,4,5,3), ncol=3, byrow=TRUE) > t(z[3:1,3:1])[3:1,] > > > -- > Curt Seeliger, Data Ranger > Raytheon Information Services - Contractor to ORD > seeliger.c...@epa.gov > 541/754-4638
Now that *is* neat! Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <ted.hard...@manchester.ac.uk> Fax-to-email: +44 (0)870 094 0861 Date: 18-Mar-10 Time: 21:00:28 ------------------------------ XFMail ------------------------------ ______________________________________________ R-help@r-project.org 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.
