Hi All, I am writing a function to predict values based on a model. It works fine as long as the formula just uses regular variable names. I am having a problem when the variables are wrapped with a function call. For example:
m <- lm(mpg ~ factor(cyl), data = mtcars) ## I get the column names using as.character(attr(terms(m), "variables"))[-1L] ## which gives the same column names as in # m$model predict(m, m$model) # returns an error that 'cyl' is not found Is there an easy way to get just the variable names or a template data frame that I can populate with my own values from a model object? My best idea right now is to use a regular expression to strip away everything before and after (). This would break down for things like I(cyl^2), though. Any ideas or thoughts would be welcome. Thanks, Josh -- 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.
