Title stata.com egen — Extensions to generate

The last word of “frog toad newt” is “newt” and that of “frog” is “frog”. With punct(,), the last word of “frog,toad” is “toad”. The remainder or tail is whatever follows the first occurrence of pchars, which will be the empty string "" if pchars does not occur. …

  Otda, Frog, Frog toad