[zbuc]

If they were going to take that approach, it should have returned 0 then.

I think of this as "garbage in, garbage out". The function will return a numeric value -- if you give it proper input.

On two occasions I have been asked,—"Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?" In one case a member of the Upper, and in the other a member of the Lower, House put this question. I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question.