Thank you. I had looked at xtabs but misunderstood the syntax. This is great. :)
AHJ On Oct 1, 2012, at 12:53 PM, "arun" <smartpink...@yahoo.com> wrote: > Hi, > Try this: > > dat1<-read.table(text=" > ind1 ind2 coef > 1 1 1 > 1 2 0.25 > 1 3 0.125 > 1 4 0.5 > 2 2 1 > 2 1 0.25 > 2 3 0.125 > 2 4 0.5 > 3 3 1 > 3 1 0.125 > 3 2 0.125 > 3 4 0.5 > 4 4 1 > 4 1 0.5 > 4 2 0.5 > 4 3 0.5 > ",sep="",header=TRUE) > mat1<-as.matrix(xtabs(coef~ind1+ind2,data=dat1)) > > # ind2 > #ind1 1 2 3 4 > # 1 1.000 0.250 0.125 0.500 > #2 0.250 1.000 0.125 0.500 > #3 0.125 0.125 1.000 0.500 > #4 0.500 0.500 0.500 1.000 > > A.K. > > > > ----- Original Message ----- > From: AHJ <ahadjixenofon...@med.miami.edu> > To: r-help@r-project.org > Cc: > Sent: Monday, October 1, 2012 12:17 PM > Subject: [R] Transform pairwise observations into a table > > Hi, > > I have a table of pairs of individuals and a coefficient that belongs to the > pair: > > ind1 ind2 coef > 1 1 1 > 1 2 0.25 > 1 3 0.125 > 1 4 0.5 > 2 2 1 > 2 1 0.25 > 2 3 0.125 > 2 4 0.5 > 3 3 1 > 3 1 0.125 > 3 2 0.125 > 3 4 0.5 > 4 4 1 > 4 1 0.5 > 4 2 0.5 > 4 3 0.5 > > And I want to convert it to a matrix where each individual is both a row and > a column and at the intersection of each pair is the coefficient that > belongs to that pair: > > 1 2 3 4 > 1 1 0.25 0.125 0.5 > 2 0.25 1 0.125 0.5 > 3 0.125 0.125 1 0.5 > 4 0.5 0.5 0.5 1 > > If table() would allow me to specify something other than frequencies to > fill the table with, it would be what I need. I tried a few different > combinations of t() and unique() but none of it made enough sense to post as > my starting code... I am just lost. Any help would be greatly appreciated. > > Thank you, > AHJ > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/Transform-pairwise-observations-into-a-table-tp4644706.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > 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.
