What is the right way to assign a new variable into each a of list of data frames? Here is my failed attempt:
mylist <- list(df1 = data.frame(A = runif(5), B = runif(5)), df2 = data.frame(A = runif(5), B= runif(5))) lapply(mylist, function(x){x$Y <- x$A * x$B}) $df1 [1] 0.25589928 0.03446026 0.94992362 0.21388326 0.08668821 $df2 [1] 0.08771839 0.05643553 0.09036894 0.09179378 0.37394748 mylist $df1 A B 1 0.3293760 0.77692140 2 0.1283307 0.26852710 3 0.9865388 0.96288517 4 0.5087024 0.42044870 5 0.9175345 0.09447951 $df2 A B 1 0.3887178 0.2256608 2 0.2642189 0.2135938 3 0.3881635 0.2328115 4 0.9060760 0.1013091 5 0.4578424 0.8167602 I want the variable Y to be added to each data frame in mylist. thanks, Chuck -- Chuck Cleland, Ph.D. NDRI, Inc. 71 West 23rd Street, 8th floor New York, NY 10010 tel: (212) 845-4495 (Tu, Th) tel: (732) 512-0171 (M, W, F) fax: (917) 438-0894 ______________________________________________ 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.