>> for lineNum, line in enumerate(f): ... >> >> However, lineNum soon overflows and starts counting backwards. How do >> i force enumerate to return long integer? >> > Just how "soon" exactly do you read sys.maxint lines from a file? I > should have thought that it would take a significant amount of time to > read 2,147,483,647 lines ...
A modestly (but not overwhelmingly) long time: (defining our own xrange-ish generator that can handle things larger than longs) >>> def xxrange(x): ... i = 0 ... while i < x: ... yield i ... i += 1 ... >>> for i,j in enumerate(xxrange(2**33)): assert i==j ... Traceback (most recent call last): File "<stdin>", line 1, in ? AssertionError It took me about an 60-90 minutes to hit the assertion on a dual-core 2.8ghz machine under otherwise-light-load. If batch-processing lengthy log files or other large data such as genetic data, it's entirely possible to hit this limit as the OP discovered. -tkc -- http://mail.python.org/mailman/listinfo/python-list
