I think you will have to script it.
- Convert the string to a list with Words(str, "")
- Replace all values you aren't interested in with empty string (missing value) by using Substitute
- Use Loc NonMissing to find indices of non missing values
Names Default To Here(1);
a = "·cgaagt··a···········";
b = "··t·a·············c··";
c = "·····················";
list_of_chars = Words(a, "");
Substitute Into(list_of_chars, "·", "");
Show(AsList(Loc Nonmissing(list_of_chars)));
a = "··t·a·············c··";
list_of_chars = Words(a, "");
Substitute Into(list_of_chars, "·", "");
Show(AsList(Loc Nonmissing(list_of_chars)));
a = "·····················";
list_of_chars = Words(a, "");
Substitute Into(list_of_chars, "·", "");
Show(AsList(Loc Nonmissing(list_of_chars)));
//As List(Loc Nonmissing(list_of_chars)) = {2, 3, 4, 5, 6, 7, 10};
//As List(Loc Nonmissing(list_of_chars)) = {3, 5, 19};
//As List(Loc Nonmissing(list_of_chars)) = {};
-Jarmo