Not sure exactly what 'results' is doing there or 'barplot(table(i),...)' does [see ?table]
but I think this is sort of what you want to do? ## Variable assignment G01_01 <- 1:10 G01_02 <- 2:6 ## Combine to list* varnames <- paste("G01_",substring(100+1:2,2),sep="") vars <- lapply(`names<-`(as.list(varnames),varnames), function(x) eval(parse(text=x))) print(vars) ## Plotting for( i in 1:length(vars) ) { filenm <- paste("/my/dir/barplot",i,".png",sep="") barplot(...) dev.copy(png,filename=filenm,...) dev.off() } ## **Combining to list, step-by-step ## does the same thing as above digits <- substring(100+1:2,2) varnames <- paste("G01_",digits,sep="") vars <- as.list(varnames) names(varlist) <- vars # convert character string of variable names to # expressions via parse() and evaluate by eval() vars <- lapply(varlist,function(x) eval(parse(text=x))) print(vars) I think in many cases paste() is your answer... --- "Donatas G." <[EMAIL PROTECTED]> wrote: > I have a data.frame with ~100 columns and I need a barplot for each column > produced and saved in some directory. > > I am not sure it is possible - so please help me. > > this is my loop that does not work... > > vars <- list (substitute (G01_01), substitute (G01_02), substitute > (G01_03), > substitute (G01_04)) > results <- data.frame ('Variable Name'=rep (NA, length (vars)), > check.names=FALSE) > for (i in 1:length (vars)) { > barplot(table(i),xlab=i,ylab="NuomonÄs") > dev.copy(png, filename="/my/dir/barplot.i.png", height=600, width=600) > dev.off() > } > > questions: > > Is it possible to use the i somewhere _within_ a file name? (like it is > possible in other programming or scripting languages?) > > Since I hate to type in all the variables (they go from G01_01 to G01_10 > and > then from G02_01 to G02_10 and so on), is it possible to shorten this list > by > putting there another loop, applying some programming thing or so? > > -- > Donatas Glodenis > http://dg.lapas.info > > ______________________________________________ > R-help@stat.math.ethz.ch 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. > ____________________________________________________________________________________ that gives answers, not web links. ______________________________________________ R-help@stat.math.ethz.ch 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.