Abit

Use :atomics as a bit array or as an array of N-bit counters.

Documentation can be found at https://hexdocs.pm/abit.

Installation

Note: it requires OTP-21.2.1 or later.

Add abit to your list of dependencies in mix.exs:

def deps do
  [
    {:abit, "~> 0.3"}
  ]
end

API summary

See https://hexdocs.pm/abit for full documentation.

Abit - use :atomics as a bit array

• Abit.bit_count/1 - Returns count of bits in atomics.
• Abit.union/2 - Unions bits of 2 atomics using Bitwise OR.
• Abit.intersect/2 - Intersects bits of 2 atomics using Bitwise AND.
• Abit.difference/2 - Clears bits in left atomics that are set in right using Bitwise AND NOT.
• Abit.symmetric_difference/2 - Symmetric difference of 2 atomics using Bitwise XOR.
• Abit.invert/1 - Inverts all bits in atomics using Bitwise NOT.
• Abit.bit_position/1 - Returns the bit's position in an atomics array.
• Abit.bit_at/2 - Returns the bit at a given position from atomics.
• Abit.set_bit_at/3 - Sets the bit in atomics at the given position to the given bit (0 or 1).
• Abit.toggle_bit_at/2 - Toggles the bit in atomics at the given position.
• Abit.clear/1 - Sets all elements in the atomics reference to 0.
• Abit.set_bits_count/1 - Returns the number of bits set to 1 in atomics.
• Abit.hamming_distance/2 - Returns the bitwise hamming distance between the 2 given atomics.
• Abit.to_list/1 - Returns a flat list of every atomic value converted into a list of bits.

Abit.Atomics - utility functions for working with Erlang's :atomics

• Abit.Atomics.to_list/1 - Converts an :atomics reference to a list of integers.
• Abit.Atomics.member?/2 - Checks if an integer is present in the :atomics reference.
• Abit.Atomics.serialize/1 - Serializes an :atomics reference into a binary.
• Abit.Atomics.deserialize/1 - Deserializes a binary into an :atomics reference.

Abit.Counter - use :atomics as an array of N-bit counters

• Abit.Counter.new/3 - Create a new array of counters. Returns %Abit.Counter{} struct.
• Abit.Counter.clear/1 - Sets all elements in the counter array to 0.
• Abit.Counter.get/2 - Returns the value of counter at the given index.
• Abit.Counter.put/3 - Puts the value into counter at the given index.
• Abit.Counter.add/3 - Adds the increment to counter at the given index.
• Abit.Counter.member?/2 - Returns true if any counter has the given value, false otherwise.
• Abit.Counter.get_all_at_atomic/2 - Returns all counters from atomics at a given index.

Abit.Bitmask - helper functions for bitmasks

• Abit.Bitmask.set_bits_count/1 - Returns the number of bits set to 1 in the given integer.
• Abit.Bitmask.bit_at/2 - Returns the bit at a given position in the given integer.
• Abit.Bitmask.set_bit_at/3 - Sets a bit in the given integer at the given position to a given bit (0 or 1).
• Abit.Bitmask.toggle_bit_at/2 - Toggles the bit at a given position in the given integer.
• Abit.Bitmask.hamming_distance/2 - Returns the bitwise hamming distance between the 2 given integers.
• Abit.Bitmask.to_list/2 - Converts the given integer to a list of bits.

License

Abit is MIT licensed.