During some experimentation in preparing R lessons I encountered this behaviour which I can not explain fully
mat <- matrix(1:16, 4,4) df1 <- data.frame(mat) > mean(df1) X1 X2 X3 X4 2.5 6.5 10.5 14.5 Expected, documented > median(df1) [1] 6.5 10.5 Rather weird, AFAIK there shall not be an issue with data frame at least I did not find any in help page. I tracked it down probably to an As.Is operation with object and subsequent sorting in median.default. I know other (*apply) ways how to compute median for data frames so I just would like to hear an opinion about this behaviour from more experienced people. Thank you Best regards Petr ______________________________________________ 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.
