Try this: do.call(rbind, lapply(comb, '[', 'a'))
On Wed, May 14, 2008 at 4:40 PM, <[EMAIL PROTECTED]> wrote: > Using R 2.6.2, say I have the following list of lists, "comb": > > data1 <- list(a = 1, b = 2, c = 3) > data2 <- list(a = 4, b = 5, c = 6) > data3 <- list(a = 3, b = 6, c = 9) > comb <- list(data1 = data1, data2 = data2, data3 = data3) > > So that all names for the lowest level list are common. How can I most > efficiently access all of the sublist items "a" indexed by the outer > list names? For example, I can loop through comb[[i]], unlisting as I > go, and then look up the field "a", as below, but there has got to be a > cleaner way. > > finaldata <- double(0) > for(i in 1:length(names(comb))) { > test <- unlist(comb[[i]]) > finaldata <- c(finaldata, test[which(names(test) == "a")]) > } > data.frame(names(comb), finaldata) > > Gives what I want: > names.comb. finaldata > 1 data1 1 > 2 data2 4 > 3 data3 3 > > Any help you can give would be greatly appreciated. Thanks. > -------------------------------------------------------- > > > > This information is being sent at the recipient's reques...{{dropped:16}} > > ______________________________________________ > 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. > -- Henrique Dallazuanna Curitiba-Paraná-Brasil 25° 25' 40" S 49° 16' 22" O [[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.