A rule of thumb is that if the solution seems a lot harder than the task, there is probably a better approach. I think you want something like:
lapply(gnuff[nam], function(x) x$LE) Patrick Burns patr...@burns-stat.com +44 (0)20 8525 0696 http://www.burns-stat.com (home of "The R Inferno" and "A Guide for the Unwilling S User") stefan.d...@gmail.com wrote:
Hello, I have a maybe trivial question, but I simply don't understand well enought how to work with text/strings: I have a rather compelx data structure, a big list with several sub-lists/dataframes and for certain calculations (which I do in loops), I only need a certain group of sub-lists/dataframes, which I want to specify with a name vector and paste together the object name and pass it on to a function. Here an (hopefully) instructive example #Data Example gnuff<-list() gnuff$IHD$LE<-66 gnuff$LUNG$LE <-55 #This is the list, where I collect data for different diseases at the second level of the list #Now I want to do calcualtions just for these two diseases and the sub-list "LE" within these diseases nam <- c("LUNG","IHD") for(i in 1:2) x[i] <- paste("gnuff",nam[i],"LE",sep="$") /2 x #So I try to paste the name of the object which I mean (gnuff$IHD$LEand gnuff$LUNG$LE, respectivly), but R treats them as a string and not as the name of an object. # I tried seveal commands to make it treat like an object name (the get() looked most promising), but so far to no avail #commands I have tried j <- eval(paste("gnuff",nam[i],"LE",sep="$")) parse(paste("gnuff",nam[i],sep="$")) quote(paste("gnuff",nam[i],sep="$")) get(paste("gnuff",nam[i],sep="$")) Anybody any hints where to look? Thanks and have a great weekend! Best, Stefan ______________________________________________ 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.