Ptit_Bleu wrote: > Hi, > > I have a vector called nfichiers of 138 names of file whose extension is .P0 > or P1 ... to P8. > The script is not the same when the extension is P0 or P(1 to 8). > > Examples of file names : > [128] "Output0.P0" > [129] "Output0.P1" > [130] "Output0.P2" > [131] "Output01102007.P0" > [132] "Output01102007.P1" > [133] "Output01102007.P2" > [134] "Output01102007.P3" > [135] "Output01102007.P4" > > > To extract the names of file with .P0 extension I wrote : > nfichiers[grep(".P0", nfichiers)] > For the other extensions : > nfichiers[grep(".P[^0]", nfichiers)] > > But for the last, I get a length of 138 that is the length of the initial > vector although I have 130 files with .P0 extension. > > So I tried "manually" with a small vector : >> s > [1] "aa.P0" "bb.P0" "cc.P1" "dd.P2" >> s[grep(".P[^0]", s)] > [1] "cc.P1" "dd.P2"
I guess you want grep("\\.P0$", nfichiers) Otherwise you get "XP0X" as a positive as well. And for the others: grep("\\.P[^0]$", nfichiers) with ".P[^0]", you'd get "XPXX" as positive, for example... because you are looking for something that contains a P that is preceded by any character and followed by some non-zero character. Uwe Ligges > It works !!! > > Has someone an idea to solve this small problem ? > Thanks in advance, > Ptit Bleu. > > ______________________________________________ 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.