Well, your second post is rather confusing too, as is your not reproducible code.
If I understand correctly, you just want to change names of files in a directory according to some rules, which you did not clerly specify. First I am not sure if R is the best tool for it. Nevertheless, you do not change a contents of any file, just change the name. I found this with simple answer questioning internet. http://stackoverflow.com/questions/10758965/how-do-i-rename-files-using-r Is this what you want? Here is another possibility https://www.r-bloggers.com/operating-on-files-with-r-copy-and-rename/ Anyway the concept I would use is. #read old names old_names <- list.files(old_path) #setting new names (you did not explain how do you want to do this) new_names <- some vector of new names If order of names is correct file.rename(old_names, new_names) othervise it would be needed correctly order both vectors before file.rename. The crucial information is how do you want set the new names vector. You shold specify it by reproducible way if you want more precise answer. Copying files is in this case best done by OS itself. Cheers Petr > -----Original Message----- > From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Luanna > Dixson > Sent: Monday, January 23, 2017 6:39 PM > To: r-help@r-project.org > Subject: Re: [R] Suggestions for vectorizing/double loop > > Hi all, > > Thanks very much for your help! You are correct in thinking the list is the > same as before, actually, my question was more about how to do the next > steps, where I needed to match the filenames of the files in my directory > with old (i.e current) and new file name prefixes in my list. For each match I > then wanted to rename the original file using the corresponding new > filename prefix from the list. > > Sorry for being a bit confusing, I didn't post my first attempt to do this at > first > as my code just didn't work at all, but I have had another go using a matrix > instead and I think this does the job. > > old_path="./old/" > new_path="./new/" > > old_names <- list.files(old_path) > head(old_names) > > oldnames=c('1002', '1003') > newnames=c('1002_new', '1003_new') > mapping=cbind(oldnames,newnames) > head(mapping) > > for (i in old_names){ > temp <- unlist(strsplit(i, "[.]"))[1] > n <- which(is.element(mapping,temp)) > if(length(n)>0) { > #copy the file to the new folder > #re name it and the name is paste(mapping[n,2], '.xls', sep="") > print(paste(mapping[n,2], '.xls', sep="")) > newnames <- paste(mapping[n,2], '.xls', sep="") > file.copy(from = paste(old_path, i, sep=""), > to = paste(new_path, newnames)) > } > } > > > On 23 January 2017 at 13:28, Luanna Dixson > <justanotherdigress...@gmail.com> > wrote: > > > I need to rename a bunch of files, by searching for string matches in > > a list. Each list element containings a character with the old > > filename that I want to match to, and the new file name that I want to > rename by. > > > > For instance, here filename '1001.xls' should match to > > list[[1]]$oldname and I want to rename it to 'newa.xls' from > list[[1]]$newname. > > > > The actual new file names I have will feature a random alphanumeric > > number and the list will have a length of ~600. > > > > > > # files I want to rename > > > > files with old file name =c('1001.xls', '1002.xls') > > > > # list with old file names and new file names > > > > oldnames=c('1001', '1002', '1003') > > > > newnames=c('newa', 'newb', 'newc') > > > > df=data.frame(oldnames,newnames) > > > > list <- split(df, rownames(df)) > > > > > > # turn list elements in character > > > > for(i in 1:length(list)) list[[i]]$oldnames=as. > > character(list[[i]]$oldnames) > > > > for(i in 1:length(list)) list[[i]]$newnames=as. > > character(list[[i]]$newnames) > > > > > > I heard that it would be better to vectorize this than trying to do a > > double loop so if someone could give me a hint about how to do this I > > would be very grateful! > > > > [[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. ________________________________ Tento e-mail a jakékoliv k němu připojené dokumenty jsou důvěrné a jsou určeny pouze jeho adresátům. Jestliže jste obdržel(a) tento e-mail omylem, informujte laskavě neprodleně jeho odesílatele. Obsah tohoto emailu i s přílohami a jeho kopie vymažte ze svého systému. Nejste-li zamýšleným adresátem tohoto emailu, nejste oprávněni tento email jakkoliv užívat, rozšiřovat, kopírovat či zveřejňovat. Odesílatel e-mailu neodpovídá za eventuální škodu způsobenou modifikacemi či zpožděním přenosu e-mailu. V případě, že je tento e-mail součástí obchodního jednání: - vyhrazuje si odesílatel právo ukončit kdykoliv jednání o uzavření smlouvy, a to z jakéhokoliv důvodu i bez uvedení důvodu. - a obsahuje-li nabídku, je adresát oprávněn nabídku bezodkladně přijmout; Odesílatel tohoto e-mailu (nabídky) vylučuje přijetí nabídky ze strany příjemce s dodatkem či odchylkou. - trvá odesílatel na tom, že příslušná smlouva je uzavřena teprve výslovným dosažením shody na všech jejích náležitostech. - odesílatel tohoto emailu informuje, že není oprávněn uzavírat za společnost žádné smlouvy s výjimkou případů, kdy k tomu byl písemně zmocněn nebo písemně pověřen a takové pověření nebo plná moc byly adresátovi tohoto emailu případně osobě, kterou adresát zastupuje, předloženy nebo jejich existence je adresátovi či osobě jím zastoupené známá. This e-mail and any documents attached to it may be confidential and are intended only for its intended recipients. If you received this e-mail by mistake, please immediately inform its sender. Delete the contents of this e-mail with all attachments and its copies from your system. If you are not the intended recipient of this e-mail, you are not authorized to use, disseminate, copy or disclose this e-mail in any manner. The sender of this e-mail shall not be liable for any possible damage caused by modifications of the e-mail or by delay with transfer of the email. In case that this e-mail forms part of business dealings: - the sender reserves the right to end negotiations about entering into a contract in any time, for any reason, and without stating any reasoning. - if the e-mail contains an offer, the recipient is entitled to immediately accept such offer; The sender of this e-mail (offer) excludes any acceptance of the offer on the part of the recipient containing any amendment or variation. - the sender insists on that the respective contract is concluded only upon an express mutual agreement on all its aspects. - the sender of this e-mail informs that he/she is not authorized to enter into any contracts on behalf of the company except for cases in which he/she is expressly authorized to do so in writing, and such authorization or power of attorney is submitted to the recipient or the person represented by the recipient, or the existence of such authorization is known to the recipient of the person represented by the recipient. ______________________________________________ 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.
