Hi All, I have two data frames with thousand rows and several columns. My samples of the data frames are shown below
dat1 <-read.table(text="ID, x, y, z ID , x, y, z A, 10, 34, 12 B, 25, 42, 18 C, 14, 20, 8 ",sep=",",header=TRUE,stringsAsFactors=F) dat2 <-read.table(text="ID, x, y, z ID, weight A, 0.25 B, 0.42 C, 0.65 ",sep=",",header=TRUE,stringsAsFactors=F) My goal is to create an index value for each ID by mutliplying the first row of dat1 by the second column of dat2. (10*0.25 ) + (34*0.42) + (12*0.65)= 24.58 (25*0.25 ) + (42*0.42) + (18*0.65)= 35.59 (14*0.25 ) + (20*0.42) + ( 8*0.65)= 19.03 The desired out put is dat3 ID, Index A 24.58 B 35.59 C 19.03 How do I do it in an efficent way? Thank you, ______________________________________________ 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.
