added methods to bitarray.rb

[biopieces.git] / code_ruby / lib / maasha / bitarray.rb

diff --git a/code_ruby/lib/maasha/bitarray.rb b/code_ruby/lib/maasha/bitarray.rb
index 4cb77b4ce8c53d65c1791d02a99e449301a8c20e..e65ab3ca4429f9be7da258c6bb8a2f1f8b0dc673 100644 (file)
--- a/code_ruby/lib/maasha/bitarray.rb
+++ b/code_ruby/lib/maasha/bitarray.rb
@@ -32,7 +32,7 @@ class BitArrayError < StandardError; end
 # Class containing methods for creating and manipulating a bit array.
 class BitArray
   attr_accessor :byte_array
-  attr_reader :size
+  attr_reader   :size
 
   # Method to initialize a new bit array of a given size in bits.
   def initialize(size)
@@ -41,6 +41,20 @@ class BitArray
     @count_array = init_count_array
   end
 
+  # Method that sets all bits in the bit array.
+  def fill!
+    self.byte_array.fill!(~0)
+
+    self
+  end
+
+  # Method that unsets all bits in the bit array.
+  def clear!
+    self.byte_array.fill!(0)
+
+    self
+  end
+
   # Method to set a bit to 1 at a given position in the bit array.
   def bit_set(pos)
     raise BitArrayError, "Position #{pos} must be an integer."              unless pos.is_a? Fixnum
@@ -49,6 +63,17 @@ class BitArray
     @byte_array[byte_pos(pos)] = @byte_array[byte_pos(pos)] | bit_pos(pos)
   end
 
+  # Method to set a bit to 0 at a given position in the bit array.
+  def bit_unset(pos)
+    raise BitArrayError, "Position #{pos} must be an integer."              unless pos.is_a? Fixnum
+    raise BitArrayError, "Position #{pos} outside of range: 0 ... #{@size}" unless (0 ... @size ).include? pos
+
+    mask = bit_pos(pos)
+    mask = ~mask
+
+    @byte_array[byte_pos(pos)] = @byte_array[byte_pos(pos)] & mask
+  end
+
   # Method to check if a bit at a given position in the bit array is set.
   def bit_set?(pos)
     raise BitArrayError, "Position #{pos} must be an integer."              unless pos.is_a? Fixnum
@@ -106,6 +131,13 @@ class BitArray
     self
   end
 
+  # Method to flip all bits in a bit array. All set bits become unset and visa versa.
+  def ~
+    self.byte_array = ~(self.byte_array)
+
+    self
+  end
+
   # Method to convert a bit array to a string.
   def to_s
     string = ""