Hi Alan, > I have a general question about reshaping a wide data frame using the > "reshape" command. I have a data frame consisting of 108 columns that > I would like to convert to a long table and remove the metadata > (embedded in the column names of the wide table) to new metadata > columns in the long format.
You could try using the reshape _package_ (http://had.co.nz/reshape) to do this: data1 <- data.frame( name = 0:10, mediacont.21.MC1A = 10:20, mediatreat.20.MD1A = 30:40, treat.20.T2C = 50:60, treat.20.T2A = 70:80, condtp.20.C2A = 90:100, condtp.20.C2B = 100:110, mediacont.21.MC1B = 120:130 ) dm <- melt(data1, id = "name") head(dm) ids <- colsplit(dm$variable, "\\.", c("treatment","time","rep")) dm <- cbind(dm, ids) dm$variable <- NULL dm$time <- as.numeric(dm$time) It's then easy to reshape and aggregate as required: cast(dm, treatment ~ time, mean) cast(dm, ... ~ treatment) Hadley -- http://had.co.nz/ ______________________________________________ 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.
