Counting bits in large string / bit vector

[Nizamov Shawkat]

> Is there an equivalent command in python that would immediately provide the
> number of set bits in a large bit vector/string
>

You might be able to achieve this using numpy boolean array and, e.g,
the arithmetic sum function or something similar.
There is also another library  http://pypi.python.org/pypi/bitarray
which resembles numpy's bit array.

Hope it helps,
S.Nizamov