On Mar 13, 9:05 am, vsoler <vicente.so...@gmail.com> wrote: > Say that "m" is a tuple of 2-tuples > > m=(('as',3), ('ab',5), (None, 1), ('as',None), ('as',6)) > > and I need to build a "d" dict where each key has an associated list > whose first element is the count, and the second is the sum. If a 2- > tuple contains a None value, it should be discarded. > > The expected result is: > d={'as':[2, 9], 'ab': [1,5]} > > How should I proceed? So far I have been unsuccessful. I have tried > with a "for" loop.
Post your first try at a for loop, and people might be willing to point out problems, but this is such a basic for loop that it is unlikely that anybody is going to write your ENTIRE homework for you. Regards, Pat -- http://mail.python.org/mailman/listinfo/python-list