Hi Steven, If I understood correctly, this might do what you want:
c(t(m)) HTH, Jorge On Sat, Jun 5, 2010 at 2:12 PM, steven mosher <mosherste...@gmail.com>wrote: > Given a matrix of m*n, I want to reorder it as a vector, using a row major > transpose. > > so: > > > m<-matrix(seq(1,48),nrow=6,byrow=T) > > m > [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] > [1,] 1 2 3 4 5 6 7 8 > [2,] 9 10 11 12 13 14 15 16 > [3,] 17 18 19 20 21 22 23 24 > [4,] 25 26 27 28 29 30 31 32 > [5,] 33 34 35 36 37 38 39 40 > [6,] 41 42 43 44 45 46 47 48 > > I want to reorder this as a vector copying by row, so that the final vector > has elements ordered thusly: row 1, column 1:N (m[1,1:n]) maps to > row 1-n, and m[2,1:n] maps to row[n+1:2n] ... > > this obviously is not a solution: as the inherent column major storage > paradigm of a matrix > defeats the approach. > > dim(m)<-c(48,1) > > m > [,1] > [1,] 1 > [2,] 9 > [3,] 17 > [4,] 25 > [5,] 33 > [6,] 41 > [7,] 2 > [8,] 10 > [9,] 18 > [10,] 26 > [11,] 34 > [12,] 42 > [13,] 3 > [14,] 11 > [15,] 19 > [16,] 27 > [17,] 35 > [18,] 43 > [19,] 4 > [20,] 12 > [21,] 20 > [22,] 28 > [23,] 36 > [24,] 44 > [25,] 5 > [26,] 13 > [27,] 21 > [28,] 29 > [29,] 37 > [30,] 45 > [31,] 6 > [32,] 14 > [33,] 22 > [34,] 30 > [35,] 38 > [36,] 46 > [37,] 7 > [38,] 15 > [39,] 23 > [40,] 31 > [41,] 39 > [42,] 47 > [43,] 8 > [44,] 16 > [45,] 24 > [46,] 32 > [47,] 40 > [48,] 48 > > > I already have a version that loops through the data ( this is actually a > portion of a data frame ) to reorder > this into a vector, but I was hoping there was an elegant way > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > [[alternative HTML version deleted]] ______________________________________________ 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.
