Expand ranges defined by “from” and “to” columns

Question

I have a data frame containing \"name\" of U.S. Presidents, the years when they start and end in office, (\"from\" and \"to\" columns

Answer 1

Here is a quick base-R solution, where Df is your data.frame:

do.call(rbind, apply(Df, 1, function(x) {
  data.frame(name=x[1], year=seq(x[2], x[3]))}))

It gives some warnings about row names, but appears to return the correct data.frame.