On Tue, Aug 23, 2011 at 10:34 AM, Noah Silverman <noahsilver...@ucla.edu> wrote: > Hi, > > Looking at a large data set with many factors. > > I would like to expand each factor variable into multiple new variables for > each level. (0,1) coding. > > My first though was just to code a big nasty loop, to take each level and > cbind a column onto my data set. But, that seems painful. There must be a > better way. > > Is there an "easy" way to do this in R?
Sure, just use model matrix, e.g.: model.matrix(~ -1 + factor(cyl), data = mtcars) Cheers, Josh > > (Note, I don't want to internally represent the levels in the data set, but > physically have new columns for each level with a binary indicator.) > > Thanks! > > -- > Noah Silverman > UCLA Department of Statistics > 8117 Math Sciences Building > Los Angeles, CA 90095 > > ______________________________________________ > 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. > -- Joshua Wiley Ph.D. Student, Health Psychology Programmer Analyst II, ATS Statistical Consulting Group University of California, Los Angeles https://joshuawiley.com/ ______________________________________________ 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.
