En Tue, 06 Feb 2007 20:31:17 -0300, Sick Monkey <[EMAIL PROTECTED]> escribió:
> Even though I am starting to get the hang of Python, I continue to find > myself finding problems that I cannot solve. > I have never used dictionaries before and I feel that they really help > improve efficiency when trying to analyze huge amounts of data (rather > than > having nested loops). You are right, a list is not the right data structure in your case. But a dictionary is a mapping from keys to values, and you have no values to store. In this case one should use a set: like a list, but without ordering, and no duplicated elements. Also, it's not necesary to read all lines at once, you can process both files line by line. And since reading both files appears to be the same thing, you can make a function: def mailsfromfile(fname): result = set() with open(fname,'r') as finput: for line in finput: mails = some_regular_expression.findall(line) if mails: result.update(mails) return result mails1 = mailsfromfile(f1name) mails2 = mailsfromfile(f2name) for mail in mails1 & mails2: # & = set intersection, mails present on both files # write mail to output file -- Gabriel Genellina -- http://mail.python.org/mailman/listinfo/python-list