Dear R Helpers, I am trying to do calculations on multiple data frames and do not want to create a list of them to go through each one. I know that lists have many wonderful advantages, but I believe the better thing is to work df by df for my particular situation. For background, I have already received some wonderful help on how to handle some situations, such as removing columns:
x=as.data.frame(matrix(c(1,2,3, 1,2,3, 1,2,2, 1,2,2, 1,1,1),ncol=3,byrow=T)) y=as.data.frame(matrix(c(1,2,3, 1,2,3, 1,2,2, 1,2,2, 1,1,1),ncol=3,byrow=T)) z=as.data.frame(matrix(c(1,2,3, 1,2,3, 1,2,2, 1,2,2, 1,1,1),ncol=3,byrow=T)) for(i in letters[24:26] ) assign( i, subset(get(i), select=-c(V1)) ) x y z And I figured how to do further processing using functions: myfunc<-function(DF){ DF$V4<-DF$V2+DF$V3 return(DF) } for(i in letters[24:26] ) assign( i, myfunc(get(i))) But if I want to do a rather simple calculation and store it as a new column in each data frame such as x$V4<-x$V2+x$V3 y$V4<-y$V2+y$V3 z$V4<-z$V2+z$V3 is there a simpler way to do this than building a function as shown above? I tried a few variations of i<-24 assign(paste(i,"$V4",sep=""),paste(get(i),"$V2+",get(i),"$V3",sep="")) but keep getting syntax errors. If anyone could help with the syntax as to how to accomplish the calculation above without building a function, I would really appreciate it. --John Sparks ______________________________________________ R-help@r-project.org 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.