Hi, Try: Df1[duplicated(Df1),] Df1[duplicated(Df1,fromLast=TRUE),] A.K.
----- Original Message ----- From: Arnaud Michel <michel.arn...@cirad.fr> To: R help <r-help@r-project.org> Cc: Sent: Tuesday, September 17, 2013 2:14 PM Subject: [R] delete some lines of a dataframe Hi I have a dataframe Df1 dput(Df1) structure(list(Mat = c(141, 141, 157, 157, 188, 188, 232, 232, 253, 253, 253, 254, 254, 254, 254, 256, 256, 264, 264), Prenom = c("Pierre", "Pierre", "Jean-Claude", "Jean-Claude", "Jean-Louis", "Jean-Louis", "Philippe", "Philippe", "Christophe", "Christophe", "Christophe", "Dominique", "Dominique", "Dominique", "Dominique", "Pierre-Luc", "Pierre-Luc", "Alain", "Alain"), Sexe = c("Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin", "Masculin"), DateNais = c("23/08/1946", "23/08/1946", "11/08/1945", "11/08/1945", "09/04/1948", "09/04/1948", "01/05/1946", "01/05/1946", "11/02/1951", "11/02/1951", "11/02/1951", "21/10/1949", "21/10/1949", "21/10/1949", "21/10/1949", "25/06/1946", "25/06/1946", "13/03/1949", "13/03/1949" )), .Names = c("Mat", "Prenom", "Sexe", "DateNais"), row.names = c("207", "208", "232", "233", "288", "289", "373", "374", "412", "413", "414", "415", "416", "417", "418", "420", "421", "436", "437" ), class = "data.frame") I want to extract of Df1 2 other dataframes : 1) delete the first line for each values of Mat Mat Prenom Sexe DateNais 208 141 Pierre Masculin 23/08/1946 233 157 Jean-Claude Masculin 11/08/1945 289 188 Jean-Louis Masculin 09/04/1948 374 232 Philippe Masculin 01/05/1946 413 253 Christophe Masculin 11/02/1951 414 253 Christophe Masculin 11/02/1951 416 254 Dominique Masculin 21/10/1949 417 254 Dominique Masculin 21/10/1949 418 254 Dominique Masculin 21/10/1949 421 256 Pierre-Luc Masculin 25/06/1946 437 264 Alain Masculin 13/03/1949 2) delete the last line for each values of Mat Mat Prenom Sexe DateNais 207 141 Pierre Masculin 23/08/1946 232 157 Jean-Claude Masculin 11/08/1945 288 188 Jean-Louis Masculin 09/04/1948 373 232 Philippe Masculin 01/05/1946 412 253 Christophe Masculin 11/02/1951 413 253 Christophe Masculin 11/02/1951 415 254 Dominique Masculin 21/10/1949 416 254 Dominique Masculin 21/10/1949 417 254 Dominique Masculin 21/10/1949 420 256 Pierre-Luc Masculin 25/06/1946 436 264 Alain Masculin 13/03/1949 Any ideas ? -- Michel ARNAUD Chargé de mission auprès du DRH DGDRD-Drh - TA 174/04 Av Agropolis 34398 Montpellier cedex 5 tel : 04.67.61.75.38 fax : 04.67.61.57.87 port: 06.47.43.55.31 ______________________________________________ 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. ______________________________________________ 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.