BitVector 1.5

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 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.

In version 1.4.1, the reset() method now returns ‘self’ to allow for cascaded inovocation with the slicing operator. This version also removes the discrepancy between the value of the __copyright__ variable in the module and the value of license variable in setup.py.

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