Tena koe Zubin Would this work for your application:
toPlot <- paste("X",i,sep="") plot(x[, toPlot]) HTH .... Peter Alspach > -----Original Message----- > From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- > project.org] On Behalf Of zubin > Sent: Wednesday, 31 March 2010 2:25 p.m. > To: r-help@r-project.org > Subject: [R] creating a variable using concatenation > > A general problem i run into, i know there must be a simple solution. > > I like to create a variable by appending a 1 for example, (i need to > loop later on from 1 to X, thus the reason for this). So i assign the > variable vplot with this value, however it has quotes and when i use it > in a barplot, it throws an error. but the tcenter$X1 does exist, its > an > element of a data frame. So if i type directly it works, but i like to > do this programmatically, as i have to generate a bunch of these plots > and need to loop. > > So how do i concatenate to create a variable, then reference that > variable in a function call? > > > R> x <- data.frame(1,2,3,4,5,6,7,8) > R> x > X1 X2 X3 X4 X5 X6 X7 X8 > 1 1 2 3 4 5 6 7 8 > R> x$X1 > [1] 1 > > R> i=1 > R> toplot <- paste("x$X",i,sep="") > R> toplot > [1] "x$X1" > > okay lets test: > > R> plot(x$X1) > -it works i see the plot > > however this DOES not work > > R> plot(toplot) > > Error in plot.window(...) : need finite 'ylim' values > In addition: Warning messages: > 1: In xy.coords(x, y, xlabel, ylabel, log) : NAs introduced by coercion > 2: In min(x) : no non-missing arguments to min; returning Inf > 3: In max(x) : no non-missing arguments to max; returning -Inf > > > Thus, that's my problem, i know it must be simple - the variable is > equal to x$X1 but it does not work in a function call? i tried many > functions - always some type of error. > > ______________________________________________ > 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.