struct BitArray
Overview
BitArray is an array data structure that compactly stores bits.
Bits externally represented as Bool
s are stored internally as
UInt32
s. The total number of bits stored is set at creation and is
immutable.
BitArray
includes all the methods in Enumerable
.
Example
require "bit_array"
ba = BitArray.new(12) # => "BitArray[000000000000]"
ba[2] # => false
0.upto(5) { |i| ba[i * 2] = true }
ba # => "BitArray[101010101010]"
ba[2] # => true
Included Modules
Defined in:
bit_array.crConstructors
-
.new(size, initial : Bool = false)
Create a new
BitArray
of size bits.
Instance Method Summary
- #==(other : BitArray)
- #==(other)
-
#[](start : Int, count : Int)
Returns count or less (if there aren't enough) elements starting at the given start index.
-
#[](range : Range(Int, Int))
Returns all elements that are within the given range.
-
#[]=(index, value : Bool)
Sets the bit at the given index.
- #hash(hasher)
-
#inspect(io : IO)
Creates a string representation of self.
-
#invert
Inverts all bits in the array.
-
#size : Int32
The number of bits the BitArray stores
-
#to_s(io : IO)
Creates a string representation of self.
-
#to_slice : Bytes
Returns a
Bytes
able to read and write bytes from a buffer. -
#toggle(index)
Toggles the bit at the given index.
- #unsafe_at(index : Int)
Instance methods inherited from module Indexable(Bool)
[](index : Int)
[],
[]?(index : Int)
[]?,
at(index : Int, &block)at(index : Int) at, bsearch(&block) bsearch, bsearch_index(&block) bsearch_index, each(&block)
each
each(*, start : Int, count : Int, &block)
each(*, within range : Range(Int, Int), &block) each, each_index(*, start : Int, count : Int, &block)
each_index(&block) : Nil
each_index each_index, empty? empty?, equals?(other, &block)
equals?(other : Indexable, &block) equals?, first(&block)
first first, first? first?, hash(hasher) hash, index(object, offset : Int = 0)
index(offset : Int = 0, &block) index, last(&block)
last last, last? last?, reverse_each(&block) : Nil
reverse_each reverse_each, rindex(value, offset = size - 1)
rindex(offset = size - 1, &block) rindex, sample(random = Random::DEFAULT) sample, size size, to_a to_a, unsafe_at(index : Int) unsafe_at, values_at(*indexes : Int) values_at, zip(other : Indexable(U), &block : T, U -> ) forall U
zip(other : Indexable(U)) : Array(Tuple(T, U)) forall U zip, zip?(other : Indexable(U), &block : T, U? -> ) forall U
zip?(other : Indexable(U)) : Array(Tuple(T, U?)) forall U zip?
Instance methods inherited from module Enumerable(Bool)
all?(&block)all? all?, any?(&block)
any? any?, chunks(&block : T -> U) forall U chunks, compact_map(&block) compact_map, count(&block)
count(item) count, cycle(n, &block)
cycle(&block) cycle, each(&block : T -> _) each, each_cons(count : Int, reuse = false, &block) each_cons, each_slice(count : Int, reuse = false, &block) each_slice, each_with_index(offset = 0, &block) each_with_index, each_with_object(obj, &block) each_with_object, find(if_none = nil, &block) find, first(count : Int)
first first, first? first?, flat_map(&block : T -> Array(U) | Iterator(U) | U) forall U flat_map, grep(pattern) grep, group_by(&block : T -> U) forall U group_by, in_groups_of(size : Int, filled_up_with : U = nil) forall U
in_groups_of(size : Int, filled_up_with : U = nil, reuse = false, &block) forall U in_groups_of, includes?(obj) includes?, index(&block)
index(obj) index, index_by(&block : T -> U) forall U index_by, join(separator, io)
join(separator = "")
join(separator, io, &block)
join(separator = "", &block) join, map(&block : T -> U) forall U map, map_with_index(&block : T, Int32 -> U) forall U map_with_index, max max, max? max?, max_by(&block : T -> U) forall U max_by, max_by?(&block : T -> U) forall U max_by?, max_of(&block : T -> U) forall U max_of, max_of?(&block : T -> U) forall U max_of?, min min, min? min?, min_by(&block : T -> U) forall U min_by, min_by?(&block : T -> U) forall U min_by?, min_of(&block : T -> U) forall U min_of, min_of?(&block : T -> U) forall U min_of?, minmax minmax, minmax? minmax?, minmax_by(&block : T -> U) forall U minmax_by, minmax_by?(&block : T -> U) forall U minmax_by?, minmax_of(&block : T -> U) forall U minmax_of, minmax_of?(&block : T -> U) forall U minmax_of?, none?(&block)
none? none?, one?(&block) one?, partition(&block) partition, product(&block)
product(initial : Number, &block)
product
product(initial : Number) product, reduce(&block)
reduce(memo, &block) reduce, reject(&block : T -> ) reject, select(&block : T -> ) select, size size, skip(count : Int) skip, skip_while(&block) skip_while, sum(initial)
sum
sum(initial, &block)
sum(&block) sum, take_while(&block) take_while, to_a to_a, to_h to_h, to_set to_set
Instance methods inherited from module Iterable(Bool)
chunk(reuse = false, &block : T -> U) forall U
chunk,
cycle(n)cycle cycle, each each, each_cons(count : Int, reuse = false) each_cons, each_slice(count : Int, reuse = false) each_slice, each_with_index(offset = 0) each_with_index, each_with_object(obj) each_with_object
Instance methods inherited from struct Struct
==(other) : Bool
==,
hash(hasher)
hash,
inspect(io : IO) : Nil
inspect,
pretty_print(pp) : Nil
pretty_print,
to_s(io)
to_s
Instance methods inherited from struct Value
==(other : JSON::Any)==(other : YAML::Any)
==(other) ==, dup dup
Instance methods inherited from class Object
!=(other)
!=,
!~(other)
!~,
==(other)
==,
===(other : JSON::Any)===(other : YAML::Any)
===(other) ===, =~(other) =~, class class, dup dup, hash(hasher)
hash hash, inspect(io : IO)
inspect inspect, itself itself, not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, tap(&block) tap, to_json(io : IO)
to_json to_json, to_pretty_json(indent : String = " ")
to_pretty_json(io : IO, indent : String = " ") to_pretty_json, to_s
to_s(io : IO) to_s, to_yaml(io : IO)
to_yaml to_yaml, try(&block) try, unsafe_as(type : T.class) forall T unsafe_as
Constructor methods inherited from class Object
from_json(string_or_io, root : String) : selffrom_json(string_or_io) : self from_json, from_yaml(string_or_io : String | IO) : self from_yaml
Constructor Detail
Create a new BitArray
of size bits.
initial optionally sets the starting value, true
or false
, for all bits
in the array.
Instance Method Detail
Returns count or less (if there aren't enough) elements starting at the given start index.
Negative indices count backward from the end of the array (-1 is the last element). Additionally, an empty array is returned when the starting index for an element range is at the end of the array.
Raises IndexError
if the starting index is out of range.
ba = BitArray.new(5)
ba[0] = true; ba[2] = true; ba[4] = true
ba # => BitArray[10101]
ba[-3, 3] # => BitArray[101]
ba[6, 1] # raise indexError
ba[1, 2] # => BitArray[01]
ba[5, 1] # => BitArray[]
Returns all elements that are within the given range.
Negative indices count backward from the end of the array (-1 is the last element). Additionally, an empty array is returned when the starting index for an element range is at the end of the array.
Raises IndexError
if the starting index is out of range.
ba = BitArray.new(5)
ba[0] = true; ba[2] = true; ba[4] = true
ba # => BitArray[10101]
ba[1..3] # => BitArray[010]
ba[4..7] # => BitArray[1]
ba[6..10] # raise IndexError
ba[5..10] # => BitArray[]
ba[-2...-1] # => BitArray[0]
Sets the bit at the given index.
Negative indices can be used to start counting from the end of the array.
Raises IndexError
if trying to access a bit outside the array's range.
ba = BitArray.new(5)
ba[3] = true
Creates a string representation of self.
ba = BitArray.new(5)
ba.to_s # => "BitArray[00000]"
Inverts all bits in the array. Falses become true
and vice versa.
ba = BitArray.new(5)
ba[2] = true; ba[3] = true
ba # => BitArray[00110]
ba.invert
ba # => BitArray[11001]
Creates a string representation of self.
ba = BitArray.new(5)
ba.to_s # => "BitArray[00000]"
Returns a Bytes
able to read and write bytes from a buffer.
The slice will be long enough to hold all the bits groups in bytes despite the UInt32
internal representation.
It's useful for reading and writing a bit array from a byte buffer directly.
Toggles the bit at the given index. A false bit becomes a true
bit, and
vice versa.
Negative indices can be used to start counting from the end of the array.
Raises IndexError
if trying to access a bit outside the array's range.
ba = BitArray.new(5)
ba[3] # => false
ba.toggle(3)
ba[3] # => true