Dear Prof Ripley, I thank you for your fast answer. In order to follow your advices :
I deleted all the objects and the tfichiers.r already created. I changed all the "tfichiers.t" of the script into "tfichiers.rda" Then I launched the script twice. The first time, as tfichiers.rda didnt' exist, it created one. During the script, I got this warning : 1: la condition a une longueur > 1 et seul le premier élément est utilisé in: if (nfichiers != "0") (translate with my words : the condition has a length superior to 1 and only the first element is used in ...) Below, you will find the results. The second launch gave the same results for nfichiers and rfichiers but for tfichiers I obtained "tfichiers". Have you some ideas to help me (because I really have none ...) Again thank you, Ptit Bleu. ------------------------------------------------------ FIRST LAUNCH >nfichiers [1] "d:/Mydata/31_07_07.P0" "d:/Mydata/31_07_2007.P0" [3] "d:/Mydata/31_07_2007.P1" "d:/Mydata/31_07_2007.P2" [5] "d:/Mydata/31_07_2007.P3" > nfichiers!="0" [1] TRUE TRUE TRUE TRUE TRUE >rfichiers [1] "d:/Mydata/31_07_07.P0" "d:/Mydata/31_07_2007.P0" [3] "d:/Mydata/31_07_2007.P1" "d:/Mydata/31_07_2007.P2" [5] "d:/Mydata/31_07_2007.P3" >tfichiers [1] "d:/Mydata/31_07_07.P0" "d:/Mydata/31_07_2007.P0" [3] "d:/Mydata/31_07_2007.P1" "d:/Mydata/31_07_2007.P2" [5] "d:/Mydata/31_07_2007.P3" ---------------------------------------------------------- SECOND LAUNCH with these changes in order not to change tfichiers.rda #tfichiers<-rfichiers #save(tfichiers, file="tfichiers.rda") >nfichiers [1] "d:/Mydata/31_07_07.P0" "d:/Mydata/31_07_2007.P0" [3] "d:/Mydata/31_07_2007.P1" "d:/Mydata/31_07_2007.P2" [5] "d:/Mydata/31_07_2007.P3" > nfichiers!="0" [1] TRUE TRUE TRUE TRUE TRUE >rfichiers [1] "d:/Mydata/31_07_07.P0" "d:/Mydata/31_07_2007.P0" [3] "d:/Mydata/31_07_2007.P1" "d:/Mydata/31_07_2007.P2" [5] "d:/Mydata/31_07_2007.P3" >tfichiers "tfichiers" -- View this message in context: http://www.nabble.com/Problem-with-save-or-and-if-%28I-think-but-maybe-not-...%29-tf4333945.html#a12344036 Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@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 and provide commented, minimal, self-contained, reproducible code.