> Surely, you mean
> list dlist = dummify(x, max(c))
max(x)? That wouldn't work for a list argument, would it?
We could insist that dummify takes a series argument, not a list.
That would be backward-incompatible but probably wouldn't disturb
Of course, you are correct. I have a blind spot about max(series),
etc because I automatically think of max(list), because that is the
way Stata and other programs work. It is somewhat confusing to
combine the two distinct usages in a single function, but I will get
used to it.
But, with respect to Allin's point, I think that insisting that
dummify should take a series argument isn't a bad idea, since it
seems to me that creating multiple sets of dummy variables at one go
can easily create confusion for the unwary user.