Hi everyone, I have the following dataframe:
structure(list(Department = c("A", "A", "A", "A", "A", "A", "A", "A", "B", "B", "B", "B", "B", "B", "B", "B"), Class = c(1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L), Value = c(0L, 100L, 800L, 800L, 0L, 300L, 1200L, 0L, 0L, 0L, 400L, 400L, 200L, 800L, 1200L, 0L), Date = c("1.01.2020", "2.01.2020", "3.01.2020", "4.01.2020", "1.01.2020", "2.01.2020", "3.01.2020", "4.01.2020", "1.01.2020", "2.01.2020", "3.01.2020", "4.01.2020", "1.01.2020", "2.01.2020", "3.01.2020", "4.01.2020")), class = "data.frame", row.names = c(NA, -16L)) using dplyr I need to group by "Depatment" and "Class" and then for all the dates that are "4.01.2020" and have the "Value" greater than zero add 5 to the "Value", meaning the desired dataframe will be (NewValue column) : structure(list(Department = c("A", "A", "A", "A", "A", "A", "A", "A", "B", "B", "B", "B", "B", "B", "B", "B"), Class = c(1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L), Value = c(0L, 100L, 800L, 800L, 0L, 300L, 1200L, 0L, 0L, 0L, 400L, 400L, 200L, 800L, 1200L, 0L), Date = c("1.01.2020", "2.01.2020", "3.01.2020", "4.01.2020", "1.01.2020", "2.01.2020", "3.01.2020", "4.01.2020", "1.01.2020", "2.01.2020", "3.01.2020", "4.01.2020", "1.01.2020", "2.01.2020", "3.01.2020", "4.01.2020"), NewValue = c(0L, 100L, 800L, 805L, 0L, 300L, 1200L, 0L, 0L, 0L, 400L, 405L, 200L, 800L, 1200L, 0L)), class = "data.frame", row.names = c(NA, -16L)) Thanks a lot for any help! Elahe ______________________________________________ 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.