Bitary

Ruby-based implementation of the bit array data structure.

It's still under development, but as of now, it implements simple and well-optimized logic allowing you to set, unset and retrieve bits (as well as some extra features, see below).

Installation

Install the gem and add to the application's Gemfile by executing:

$ bundle add bitary

If bundler is not being used to manage dependencies, install the gem by executing:

$ gem install bitary

Usage

Documentation still needs to be written, but here is a breakdown of the main capabilities brought by the current bit array implementation:

require 'bitary'

bit_array_sz = Bitary.new(128) # give an explicit size. Defaults to 64 bits used per item
bit_array_ar = Bitary.new(
  [255, 10, 20],
  bpi: Bitary::BYTE # 8 bits
) # create based on some integer array

bit_array_sz.bpi # 64
bit_array_ar.bpi # 8

bit_array_ar.size # 128
bit_array_ar.size # 24

# set/unset/get
bit_array_sz[23] = 1 # set bit at position 23 (0-indexed)
bit_array_sz[23] # 1
bit_array_sz[32] # 0

bit_array_ar[0] # 1
bit_array_ar[0] = 0 # unset bit at position 0 (0-indexed)
bit_array_ar[0] # 0

# traverse
bit_array_sz.each_byte do |byte|
  # do something with each byte
end

# convert
bit_array_ar.to_a # [127, 10, 20]
bit_array_ar.to_s # "01111111 00001010 00010100"

# increase/decrease bits used per item
bit_array_ar.bpi = Bitary::LONG # 64 bits
bit_array_ar.to_a # [8_325_652]
bit_array_ar.to_s # "0000000000000000000000000000000000000000011111110000101000010100"

bit_array_sz.bpi # 64
bit_array_sz.to_a # [1_099_511_627_776, 0]
bit_array_sz.bpi = Bitary::INT # 32 bits
bit_array_sz.to_a # [256, 0, 0, 0]

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests and rake rubocop to lint your code. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and the created tag, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/Patacode/bitary.

License

The gem is available as open source under the terms of the MIT License.