There are literally tons of ways to do this sort of thing in R. In base R ?tapply and friends, especially ?ave and ?by that may be close to what you want. But there is a whole parallel universe -- the so-called "tidyverse set of packages -- that many folks prefer. This link takes you down that rabbit hole: https://dplyr.tidyverse.org/
There are still others (e.g. the data.table package). You should expect to invest a little time in learning whichever you choose. You may wish to also search a bit for tutorials on your choice -- there are many good ones out there. Bert Gunter "The trouble with having an open mind is that people keep coming along and sticking things into it." -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) On Sun, Jan 17, 2021 at 12:18 PM Bernard McGarvey < mcgarvey.bern...@comcast.net> wrote: > I have a data frame that consists of several factor columns say A, B, C, > D, and E and several columns containing numerical data, say X1, X2, .... > X10. I would like to create statistics of some of the numerical columns by > some of the factor columns. For example, > > Calculate the mean, min, and max of variables X1 and X7, by factors A, and > E. The results should look like the table below: > > Factor A Factor E mean(X1) min(x1) max(X1) mean(X7) min(x7) max(X7) > mean(X10) min(x10) max(X10) > A1 E1 > A1 E2 > A1 E3 > A2 E1 > A2 E2 > A2 E3 > > I would like the results to be returned to a data frame or other object > that I can write out using the write.csv function. I have looked at the > summarize and numSummary functions but they do not appear to be flexible > enough to do the above. > > Any help would be appreciated, > > Thanks > > Bernard McGarvey > Director, Fort Myers Beach Lions Foundation, Inc. > Retired (Lilly Engineering Fellow). > > ______________________________________________ > 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. > [[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.
