Your "assignments" (<-) are not legitimate R code that can be cut and pasted. Learn to use dput() to provide examples that we can use.
You fail to say whether the time column of df2 is a proper subset of df1 or may contain times not in df1. I shall assume the latter. You also did not say whether the time values occur in order in both data frames. I shall assume they do not. If I understand correctly,then, match and subscripting will do it, something like > df1 <-data.frame(time = 1:6, v1 = c(2,5,1,1,2,2)) > df2 <- data.frame(time = 4:3,v11 = c(112,113)) > wm <- match(df1$time,df2$time) > df1[!is.na(wm),"v1"] <- df2[na.omit(wm),"v11"] > df1 time v1 1 1 2 2 2 5 3 3 113 4 4 112 5 5 2 6 6 2 Cheers, Bert Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Sat, Feb 11, 2017 at 4:13 PM, Bhaskar Mitra <bhaskar.kolk...@gmail.com> wrote: > Hello Everyone, > > I have two data frames df1 and df2 as shown below. They > are of different length. However, they have one common column - time. > > df1 <- > time v1 v2 v3 > 1 2 3 4 > 2 5 6 4 > 3 1 3 4 > 4 1 3 4 > 5 2 3 4 > 6 2 3 4 > > > df2 <- > time v11 v12 v13 > 3 112 3 4 > 4 112 3 4 > > By matching the 'time' column in df1 and df2, I am trying to modify column > 'v1' in df1 by replacing it > with values in column 'v11' in df2. The modified df1 should look something > like this: > > df1 <- > time v1 v2 v3 > 1 2 3 4 > 2 5 6 4 > 3 112 3 4 > 4 112 3 4 > 5 2 3 4 > 6 2 3 4 > > I tried to use the 'merge' function to combine df1 and df2 followed by > the conditional 'ifelse' statement. However, that doesn't seem to work. > > Can I replace the values in df1 by not merging the two data frames? > > Thanks for your help, > > Regards, > Bhaskar > > [[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. ______________________________________________ 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.
