Hi, Not sure I understand it correctly. If you want to extract the dates with "02*": Col1<-c("11/02/2008*", "11/02/2008", "11/02/2008", "11/02/2008") Col2<-c("02*", "02", "03", "04")
Col12 <- paste(Col1, Col2) Col3 <- c("11/02/2008 02*", "11/02/2008 02", "11/02/2008 03", "11/02/2008 04") Col3[grepl("02\\*$",Col3)] #[1] "11/02/2008 02*" Col12[grepl("02\\*$",Col12)] #[1] "11/02/2008* 02*" A.K. I'm having a problem working with daylight savings dates in R. I'm downloading data in two formats. Format One Col 1: a date such as "11/03/2013" col 2: Hour ending = 02* Col1<-c("11/02/2008*", "11/02/2008", "11/02/2008", "11/02/2008") Col1<-c("02*", "02", "03", "04") Another data set is something like this: "11/03/2013 02*" Col1<-c("11/02/2008 02*", "11/02/2008 02", "11/02/2008 03", "11/02/2008 04") These data frames are very big and over multiple years with multiple values for each hour ending. I'm trying to build subsets, filter, merge tables, lookup values with dates like these. How do I go about working with the "02*"? ______________________________________________ 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.