Compressed bitset in C++
Daniel Lemire



== What is this? ==

The class EWAHBoolArray is a compressed bitset data structure.

== Licensing ==

Apache License 2.0. (Other licenses are possible.)

Update (May 20th, 2013): though by default I use the Apache License 2.0 (which is compatible with GPL 3.0), you can also consider this library licensed under GPL 2.0. 

== Limitations ==

Because of the compression type being used, you must set the bits
in increasing order (no random access while creating the bitmaps).


== Dependencies ==

None. (Will work under MacOS, Windows or Linux easily.)

Compilers tested: clang++, g++, Intel compiler, Microsoft Visual Studio

== Usage ==

make
./unit
make example
./example

== Example ==

Please see example.cpp

== Ruby wrapper ==

Josh Ferguson wrote a wrapper for Ruby. 
The implementation is packaged and installable as a ruby gem.

You can install it by typing:

gem install ewah-bitset

== Further reading ==

Please see

Daniel Lemire, Owen Kaser, Kamel Aouiche, Sorting improves
word-aligned bitmap indexes. Data & Knowledge Engineering 69 (1),
pages 3-28, 2010.
http://arxiv.org/abs/0901.3751

== Warning ==

Run your own unit tests. Report bugs.