BitVector A pure-Python memory-efficient packed representation for bit arrays This class presents a pure-Python memory efficient packed representation for bit arrays. Version 1.5.1 removes a crucial bug in the right circular shift operator. Version 1.5 should prove to be much more efficient for long bit vectors. Efficiency in BitVector construction when only its size is specified was achieved by eliminating calls to _setbit(). The application of logical operators to two BitVectors of equal length was also made efficient by eliminating calls to the padding function. Another feature of this version is the count_bits() method that returns the total number of bits set in a BitVector instance. Yet another feature of this version is the setValue() method that alters the bit pattern associated with a previously constructed BitVector. The class supports the following operators/methods: __getitem__ __setitem__ __len__ __getslice__ __str__ __iter__ __contains__ __int__ __add__ __eq__, __ne__, __lt__, __le__, __gt__, __ge__ '|' for bitwise or '&' for bitwise and '^' for bitwise xor '~' for bitwise inversion '<<' for circular shift to the left '>>' for circular shift to the right '+' for concatenation intValue(), __int__ for returning the integer value divide_into_two permute unpermute pad_from_left pad_from_right read_bits_from_file write_to_file read_bits_from_fileobject write_bits_to_fileobject slice assignment reset count_bits setValue http://RVL4.ecn.purdue.edu/~kak/dist/BitVector-1.5.1.tar.gz?download Avinash Kak 213cccecbaade86f6ca482f75cb1dfbfe21d98cb 1.5.1