Hello, I have about 2000 data files which I want to analyse. The file names are all very similar => p"variable1"_t"variable2"_c"variable3".txt There aren?t so much different variables (about 70) , just different combinations of them. To allow an easy way of handling those data files I was wondering whether R is able to do variable-substitution /command-substitution similar to shell-programming, so that I could imbed the read.table option (and further commands) in 3 loops (one for every variable in the filenames) . e.g.: for var1 in (varlist1) for var2 in (varlist2) for var3 in (varlist3) read.table("..../p$var1_t$var2_c$var3.txt") ....statistics...... done done done Cheers, Damaris
I don't know wether R does variable substitution. In order to help solve the problem, I suggest: - you might use cat in order to concatenate the files (if this fits in the problem) - you might write a shell or perl script which would write an .R file by doing the required looping, given the three variables are pretty external to the statistical data. The shell or perl procedure would generate something useful from R language, be it a list of filnames, over which a R loop could iterate in turn, be it an extensive list of 'read.table("filename_xyz.data")' for every xyz tuple. Hope this helps Haroldo 2006/4/11, Damaris Zurell <damaris at zurell.de>:> Hello, > > I have about 2000 data files which I want to analyse. > The file names are all very similar => > p"variable1"_t"variable2"_c"variable3".txt > There aren?t so much different variables (about 70) , just different > combinations of them. > To allow an easy way of handling those data files I was wondering > whether R is able to do variable-substitution /command-substitution > similar to shell-programming, so that I could imbed the read.table > option (and further commands) in 3 loops (one for every variable in the > filenames) . > > e.g.: > for var1 in (varlist1) > for var2 in (varlist2) > for var3 in (varlist3) > read.table("..../p$var1_t$var2_c$var3.txt") > ....statistics...... > done > done > done > > > Cheers, > Damaris > > ______________________________________________ > R-help at 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 >-- b l o g http://reenunciadosrenunciados.blogspot.com/ b l o g
Here are some different approaches: x <- 1 y <- 2 paste("p", x, y, ".dat", sep = "") # p12.dat sprintf("p%s%s.dat", x, y) file.path("a", "b.dat") # a/b.dat library(gsubfn) gsubfn(,,"p$x$y.dat") # p12.dat On 4/11/06, Damaris Zurell <damaris at zurell.de> wrote:> Hello, > > I have about 2000 data files which I want to analyse. > The file names are all very similar => > p"variable1"_t"variable2"_c"variable3".txt > There aren?t so much different variables (about 70) , just different > combinations of them. > To allow an easy way of handling those data files I was wondering > whether R is able to do variable-substitution /command-substitution > similar to shell-programming, so that I could imbed the read.table > option (and further commands) in 3 loops (one for every variable in the > filenames) . > > e.g.: > for var1 in (varlist1) > for var2 in (varlist2) > for var3 in (varlist3) > read.table("..../p$var1_t$var2_c$var3.txt") > ....statistics...... > done > done > done > > > Cheers, > Damaris > > ______________________________________________ > R-help at 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 >