On Oct 13, 10:39 pm, Steven D'Aprano <ste...@remove.this.cybersource.com.au> wrote: > On Tue, 13 Oct 2009 16:17:58 -0500, Peng Yu wrote: > > Hi, > > > The following code does not run because range() does not accept a big > > number. > > Incorrect. > > >>> range(sys.maxint+2, sys.maxint+5) > > [2147483649L, 2147483650L, 2147483651L]
For what it's worth, there *is* a Python oddity lurking under the surface here, at least for 64-bit. Here's Python 2.6 on a 64-bit machine: >>> range(2**31-1) Traceback (most recent call last): File "<stdin>", line 1, in <module> MemoryError >>> range(2**31) Traceback (most recent call last): File "<stdin>", line 1, in <module> OverflowError: range() result has too many items The first call tries to allocate a list containing 2**31-1 integers. At 32 bytes per entry (8 for the list pointer, 24 for the integer itself), that's not surprising on a machine with < 64 Gb of memory. The second call, however, doesn't even try to allocate the memory, but decides that the range can't be represented. That's not right: this is an LP64 machine, so the size of the list can be represented, and the start, stop and step values are representable as C longs (which is what CPython uses internally for this purpose). On a machine with >64 Gb of memory, this call should succeed. On an LP64 machine with <64 Gb of memory, it should produce MemoryError, not OverflowError. Mark -- http://mail.python.org/mailman/listinfo/python-list
