where is the problem? input: A<-c(2,3,2); B<-c(1,2,1); C<-c(4,4,5); D<-c(3,5,4) df<-data.frame(A,B,C,D) c1<-1:2; c2<-3:4 df[,c1]*df[,c2]
output: A B 1 8 3 2 12 10 3 10 4 Peter Wolf Christoph Scherber wrote: >Dear R users, > >Suppose I have 2 parts of a dataframe, say > >ABCD >2143 >3245 >2154 > >(the real dataframe is 160 columns with each 120 rows) > >and I want to multiply every element in [,A:B] with every element in [,C:D]; >What is the most elegant way to do this? > >I´ve been thinking of converting [,A:B] to a matrix, and then >multiplying it with the inverse of [,C:D]; would that be correct? > >The result should look like > >E;F >8;3 >12;10 >10;4 > >Thanks very much for any suggestions >Christoph > >______________________________________________ >[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 > ______________________________________________ [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
