FrozenBitmap

FrozenBitMap

The major addition of this release is the new class FrozenBitMap. It is analogous to the frozenset of the standard library: a FrozenBitMap is an immutable object that can be hashed.
The main usecase is to use them in sets or dictionnaries:

from pyroaring import FrozenBitMap
mydict = {FrozenBitMap() : 'an empty bitmap',
          FrozenBitMap([1, 3, 5, 7, 9]) : 'some odd numbers',
          FrozenBitMap([1, 2, 4, 8, 16]) : 'powers of two'
}

Optimizations

Several performance optimizations have been implemented :

• Getting a small slice from a large bitmap used to be very long. This is now fixed.
• Two methods run_optimize() and shrink_to_fit() have been added. They call their CRoaring counterpart.

Information

The version number and the git hash of both pyroaring and CRoaring are available from the module:

import pyroaring
print(pyroaring.__version__)
print(pyroaring.__git_version__)
print(pyroaring.__croaring_version__)
print(pyroaring.__croaring_git_version__)