- [ ] Improve `expand_spline()`: Allow user to pass vector argument specifying which columns should be expanded (default would be: all numeric columns) - [ ] Create an `expand_factor()` function to do the same for factors - [ ] Make sure all combinations of factors, splines, and non-expanded variables work well together
expand_spline(): Allow user to pass vector argument specifying which columns should be expanded (default would be: all numeric columns)expand_factor()function to do the same for factors