Hey, You could also use (after initializing x):
x[lower.tri(x)] <- data$k x <- t(x) Cheers, Tsjerk On Feb 16, 2012 6:59 PM, "Rui Barradas" <rui1...@sapo.pt> wrote: Hello, I'm glad it helped. The difference in the ordering is due to the fact that R defaults to column-first ordering. David's solution uses row-first (which is what you wanted). Rui Barradas -- View this message in context: http://r.789695.n4.nabble.com/built-a-lower-triangular-matrix-from-dataframe-tp4390813p4394543.html Sent from the R help mailing list archive at Nabble.com. __________________________________________... [[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.