Hi Michel, You could try:
df1New<-droplevels(TEST[with(TEST,ave(seq_along(Matricule),Matricule,FUN=min)),]) row.names(df1New)<-1:nrow(df1New) df2New<-droplevels(TEST[with(TEST,ave(seq_along(Matricule),Matricule,FUN=max)),]) row.names(df2New)<-1:nrow(df2New) identical(df1New,df1) #[1] TRUE identical(df2New,df2) #[1] TRUE A.K. ----- Original Message ----- From: Arnaud Michel <michel.arn...@cirad.fr> To: R help <r-help@r-project.org> Cc: Sent: Wednesday, July 24, 2013 2:39 AM Subject: [R] Change values in a dateframe Hello I have the following problem : The dataframe TEST has multiple lines for a same person because : there are differents values of Nom or differents values of Prenom but the values of Matricule or Sexe or Date.de.naissance are the same. TEST <- structure(list(Matricule = c(66L, 67L, 67L, 68L, 89L, 90L, 90L, 91L, 108L, 108L, 108L), Nom = structure(c(1L, 2L, 2L, 4L, 8L, 5L, 6L, 9L, 3L, 3L, 7L), .Label = c("CHICHE", "GEOF", "GUTIER", "JACQUE", "LANGUE", "LANGUE-LOPEZ", "RIVIER", "TRU", "VINCENT" ), class = "factor"), Prenom = structure(c(8L, 3L, 4L, 5L, 1L, 2L, 2L, 9L, 6L, 7L, 7L), .Label = c("Edgar", "Elodie", "Jeanine", "Jeannine", "Michel", "Michele", "Michèle", "Michelle", "Victor" ), class = "factor"), Sexe = structure(c(1L, 1L, 1L, 2L, 2L, 1L, 1L, 2L, 1L, 1L, 1L), .Label = c("Féminin", "Masculin"), class = "factor"), Date.de.naissance = structure(c(4L, 2L, 2L, 7L, 6L, 5L, 5L, 1L, 3L, 3L, 3L), .Label = c("03/09/1940", "04/03/1946", "07/12/1947", "18/11/1945", "27/09/1947", "29/12/1936", "30/03/1935"), class = "factor")), .Names = c("Matricule", "Nom", "Prenom", "Sexe", "Date.de.naissance"), class = "data.frame", row.names = c(NA, -11L)) I would want to make homogeneous the information and would like built 2 dataframes : df1 wich has the value of Nom and Prenom of the first lines of TEST when there are different values. The other values (Matricule or Sexe or Date.de.naissance) are unchanged df1 <- structure(list(Matricule = c(66L, 67L, 67L, 68L, 89L, 90L, 90L, 91L, 108L, 108L, 108L), Nom = structure(c(1L, 2L, 2L, 4L, 6L, 5L, 5L, 7L, 3L, 3L, 3L), .Label = c("CHICHE", "GEOF", "GUTIER", "JACQUE", "LANGUE", "TRU", "VINCENT"), class = "factor"), Prenom = structure(c(6L, 3L, 3L, 4L, 1L, 2L, 2L, 7L, 5L, 5L, 5L), .Label = c("Edgar", "Elodie", "Jeanine", "Michel", "Michele", "Michelle", "Victor" ), class = "factor"), Sexe = structure(c(1L, 1L, 1L, 2L, 2L, 1L, 1L, 2L, 1L, 1L, 1L), .Label = c("Féminin", "Masculin"), class = "factor"), Date.de.naissance = structure(c(4L, 2L, 2L, 7L, 6L, 5L, 5L, 1L, 3L, 3L, 3L), .Label = c("03/09/1940", "04/03/1946", "07/12/1947", "18/11/1945", "27/09/1947", "29/12/1936", "30/03/1935"), class = "factor")), .Names = c("Matricule", "Nom", "Prenom", "Sexe", "Date.de.naissance"), class = "data.frame", row.names = c(NA, -11L)) df2 wich has the value of Nom and Prenom of the last lines of TEST when there are different values. The other values (Matricule or Sexe or Date.de.naissance) are unchanged. df2 <- structure(list(Matricule = c(66L, 67L, 67L, 68L, 89L, 90L, 90L, 91L, 108L, 108L, 108L), Nom = structure(c(1L, 2L, 2L, 3L, 6L, 4L, 4L, 7L, 5L, 5L, 5L), .Label = c("CHICHE", "GEOF", "JACQUE", "LANGUE-LOPEZ", "RIVIER", "TRU", "VINCENT"), class = "factor"), Prenom = structure(c(6L, 3L, 3L, 4L, 1L, 2L, 2L, 7L, 5L, 5L, 5L), .Label = c("Edgar", "Elodie", "Jeannine", "Michel", "Michèle", "Michelle", "Victor"), class = "factor"), Sexe = structure(c(1L, 1L, 1L, 2L, 2L, 1L, 1L, 2L, 1L, 1L, 1L), .Label = c("Féminin", "Masculin"), class = "factor"), Date.de.naissance = structure(c(4L, 2L, 2L, 7L, 6L, 5L, 5L, 1L, 3L, 3L, 3L), .Label = c("03/09/1940", "04/03/1946", "07/12/1947", "18/11/1945", "27/09/1947", "29/12/1936", "30/03/1935"), class = "factor")), .Names = c("Matricule", "Nom", "Prenom", "Sexe", "Date.de.naissance"), class = "data.frame", row.names = c(NA, -11L)) Thank for your helps Michel -- 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.