Re: [R] formula and model.frame

Emulate lm. myFun <- function(formula, data, na.action, id, ...){ mf <- match.call(expand.dots = FALSE) m <- match(c("formula", "data", "id", "na.action"), names(mf), 0L) mf <- mf[c(1L, m)] mf$drop.unused.levels <- TRUE mf[[1L]] <- as.name("model.frame") mf

[R] formula and model.frame

Suppose I have the following function myFun <- function(formula, data){ f <- formula(formula) dat <- model.frame(f, data) dat } Applying it with this sample data yields a new dataframe: qqq <- data.frame(grade = c(3, NA, 3,4,5,5,4,3), score = rnorm(8), idVar = c(