Hello, I have two data frames with different sizes but with the same number of columns.
> df1 <- data.frame(col1 = c(1:6), col2 = c(rep("a", 3), rep("b", 3)), col3 = > c(rep("AA", 2), rep("BB", 2), rep("CC", 2)), col4=c(1,8,6,9,7,6)) > df1 col1 col2 col3 col4 1 1 a AA 1 2 2 a AA 8 3 3 a BB 6 4 4 b BB 9 5 5 b CC 7 6 6 b CC 6 > df2< - data.frame(col1 = c(1,3,5,6), col2 = c(rep("a", 2), rep("b", 2)), col3 > = c(rep("AA", 1), rep("EE", 1), rep("FF", 1), rep("CC", 1)), col4=c(1,8,5,9)) > df2 col1 col2 col3 col4 1 1 a AA 1 2 3 a EE 8 3 5 b FF 5 4 6 b CC 9 Based on col1 and col2, how can I replace any values in col3 and col4 of df1 which don't match with those of df2 by the values of df2 In this example, the result will be: > df1 col1 col2 col3 col4 1 1 a AA 1 2 2 a AA 8 3 3 a EE 8 4 4 b BB 9 5 5 b FF 5 6 6 b CC 9 Thanks a lot for your help. Have a nice day Marine [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.