The loop never assigns anything to d0, only t. The first line makes t a character string "d0$V1" (or "d0$V2" etc.). The second line assigns either 0 or 1 to t.
Looking at this, I don't think you've got into the R psychology (bad news if you want to use R, good news in many other ways). I assume d0 is a list, so could you put the V's into a vector, and then just use this: d0$V <- sapply(d1[1:10,1], grepl, d0$X0) (I haven't checked it, but it looks,like it will do the trick. It returns a logical vector, so if you need integers, then use an as.numeric() around the right hand side. Or hope that R does type conversion for you when you need it) HTH Bob On 24 April 2018 at 09:30, Luca Meyer <lucam1...@gmail.com> wrote: > Hi, > > I am trying to debug the following code: > > for (i in 1:10){ > t <- paste("d0$V",i,sep="") > t <- ifelse(regexpr(d1[i,1],d0$X0)>0,1,0) > } > > and I would like to see what code is actually processing R, how can I do > that? > > More to the point, I am trying to update my variables d0$V1 to d0$V10 > according to the presence or absence of some text (contained in the file > d1) within the d0$X0 variable. > > The code seem to run ok, if I add print(table(t)) within the loop I can see > that the ifelse procedure is working and to some cases within the d0$V1 to > d0$V10 variable range a 1 is assigned. But when checking my d0$V1 to d0$V10 > after the for loop they are all still equal to zero... > > Thanks, > > Luca > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. -- Bob O'Hara NOTE NEW ADDRESS!!! Institutt for matematiske fag NTNU 7491 Trondheim Norway Mobile: +49 1515 888 5440 Journal of Negative Results - EEB: www.jnr-eeb.org ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.