Hi All-- I have generated several 2 column data frames with variable length. The data frames have the same column names and variable types. I was trying to aggregate over the 2nd column for all the date frames, but could not figure out how.
I thought i could make them all of equal length then combine them in 1 data frame where i can use aggregate, the formula version Or to put them in a list and loop use lapply but did not know how to do that and thought there might be a simpler way. Below is an example of 3 data frames and the desired result; note that some levels don't appear in all and may be null over all variable, like the case of dd on the desired result which i would like to list all levels even if some are all null. Thanks in advance, EK df1 df2 df3 c1 c2 c1 c2 c1 c2 1 aa 1 bb 1 aa 2 aa 2 bb 2 aa 3 bb 3 cc 4 cc 4 bb 5 bb desired result c1 c2 c2 c2 aa 2 2 bb 1 2 2 cc 1 1 dd [[alternative HTML version deleted]] ______________________________________________ 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.