This has something to do with your data.frame structure see
> str(df1) 'data.frame': 3 obs. of 2 variables: $ a : int 1 2 3 $ X1: 'AsIs' int [1:3, 1:2] 1 2 3 4 5 6 > str(df2) 'data.frame': 2 obs. of 2 variables: $ a : int 1 2 $ X2: 'AsIs' int [1:2, 1:2] 11 12 13 14 This seems to work > df1<-data.frame(a=1:3, b = 1:3, c = 4:6) > str(df1) 'data.frame': 3 obs. of 3 variables: $ a: int 1 2 3 $ b: int 1 2 3 $ c: int 4 5 6 > df2<-data.frame(a=1:2, d = 11:12, e = 13:14) > str(df2) 'data.frame': 2 obs. of 3 variables: $ a: int 1 2 $ d: int 11 12 $ e: int 13 14 > merge(df1,df2) a b c d e 1 1 1 4 11 13 2 2 2 5 12 14 > merge(df1, df2, all=T) a b c d e 1 1 1 4 11 13 2 2 2 5 12 14 3 3 3 6 NA NA > 2009/9/18 Kari Ruohonen <[email protected]>: > Hi, > I have faced a problem with the merge() function when trying to merge > two data frames that have a common index but the second one does not > have cases for all indexes in the first one. With usual variables R > fills in the missing cases with NA if all=T is requested. But if the > variable is a matrix R seems to insert NA only to the first column of > the matrix and fill in the rest of the columns by recycling the values. > Here is a toy example: > >> df1<-data.frame(a=1:3,X1=I(matrix(1:6,ncol=2))) >> df2<-data.frame(a=1:2,X2=I(matrix(11:14,ncol=2))) >> merge(df1,df2) > a X1.1 X1.2 X2.1 X2.2 > 1 1 1 4 11 13 > 2 2 2 5 12 14 > # no all=T, missing cases are dropped > >> merge(df1,df2,all=T) > a X1.1 X1.2 X2.1 X2.2 > 1 1 1 4 11 13 > 2 2 2 5 12 14 > 3 3 3 6 NA 13 > # X2.1 set to NA correctly but X2.2 set to 13 by recycling. > > Can I somehow get the behaviour that the third row of the second matrix > X2 in the above example would be filled with NA for all columns? None of > the merge() options does not seem to provide a solution. > > regards, Kari > > ______________________________________________ > [email protected] 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. > ______________________________________________ [email protected] 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.
