Perhaps the OP wants the unique combinations of V1 and V2, as in R> d <- expand.grid(V1=c("x","y","z"),V2=c("x","y","z")) R> d[ as.numeric(d$V1) <= as.numeric(d$V2), ] V1 V2 1 x x 4 x y 5 y y 7 x z 8 y z 9 z z or R> V <- letters[24:26] R> rbind(t(combn(V,m=2)), cbind(V,V)) V V [1,] "x" "y" [2,] "x" "z" [3,] "y" "z" [4,] "x" "x" [5,] "y" "y" [6,] "z" "z"
Bill Dunlap Spotfire, TIBCO Software wdunlap tibco.com > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On > Behalf > Of Rolf Turner > Sent: Monday, June 10, 2013 2:20 AM > To: Gundala Viswanath > Cc: r-h...@stat.math.ethz.ch > Subject: Re: [R] How to expand.grid with string elements (the half!) > > > Your question makes no sense at all. The grid expansion > has 9 rows. In case you hadn't noticed, 9 is an odd number > (i.e. not divisible by 2). There are no "halves". > > Do not expect the list to read your mind. Instead, ask a > meaningful question. > > cheers, > > Rolf Turner > > On 10/06/13 17:25, Gundala Viswanath wrote: > > I have the following result of expand grid: > > > >> d <- expand.grid(c("x","y","z"),c("x","y","z")) > > What I want is to create a combination of strings > > but only the half of the all combinations: > > > > Var1 Var2 > > 1 x x > > 2 y x > > 3 y y > > 4 z y > > 5 x z > > 6 z z > > > > > > What's the way to do it? > > ______________________________________________ > 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. ______________________________________________ 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.