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making a python bitarray from an integer - strange results!

I'm just starting to use the bitarray package in python, and trying to make a bitarray from an integer gives me really confusing results:

>>> import bitarray
>>> bitarray.bitarray(5)
bitarray('01000')
>>> bitarray.bitarray(5)
bitarray('00010')
>>> bitarray.bitarray(5)
bitarray('00100')
>>> bitarray.bitarray(5)
bitarray('00110')

Does anyone have any idea why this would be happening??

Also: what would be a better way of making a bitarray from an int? This works, but string conversion seems like a strange way to do it...

>>> bitarray.bitarray(bin(5)[2:])
bitarray('101')

Edit: I ended up switching to bitstring, which does have an easy method of getting bitstrings from ints:

>>> bitstring.BitArray(uint=5,length=6)
BitArray('0b000101')
Solution

  • bitarray.bitarray(n) creates an uninitialized array of length n.

    As far as creating from an integer, bitarray doesn't appear to be particularly geared towards that, so you'll either have to use pack/unpack or loop over the individual bits to set them.