rational.rb in radix-2.1.1

- old
+ new

@@ -1,10 +1,11 @@
 require 'rational'
 require 'radix/numeric'
 
 module Radix
 
+  # Represents rational numbers.
   #
   class Rational < Numeric
 
     # Alternative to #new.
     def self.[](n,d=nil,b=10)
@@ -55,55 +56,74 @@
       end
     end
 
     public
 
+    # The numerator.
     #
     def numerator
       @value.numerator
     end
 
+    # The denominator.
     #
     def denominator
       @value.denominator
     end
 
+    # Is the value negative?
     #
     def negative?
       value < 0
     end
 
+    # Convert rational to new base.
     #
+    # Returns new rational. [Radix::Rational]
     def convert(base)
       self.class.new(numerator, denominator, base)
     end
 
+    # Convert to rational.
     #
+    # Returns the internal value. [Rational]
     def to_r
       value
     end
 
+    # Convert to Float by dividing the numerator by the denominator.
     #
+    # Returns the converted value. [Float]
     def to_f
       numerator.to_f / denominator.to_f
     end
 
+    # Convert to Integer by converting to Float first then
+    # appling #to_i to the float.
     #
+    # Returns the converted value. [Integer]
     def to_i
       to_f.to_i
     end
 
+    # Translate value into an array of places.
     #
+    # Returns array of places. [Array]
     def to_a(base=nil)
       if base
         convert(base).digits_encoded
       else
         digits_encoded
       end     
     end
 
+    # Convert the value into a string representation of the given base.
     #
+    # base    - the base to convert
+    # divider - symbol to used ot divide numbers
+    #
+    # Returns translated value. [String]
     def to_s(base=nil, divider=nil)
       divider = divider.to_s if divider
       if base
         convert(base).to_s(nil, divider)
       else
@@ -117,11 +137,15 @@
           end
         end
       end
     end
 
+    # Are two rationals equal?
     #
+    # TODO: this may need improvement to be more percise.
+    #
+    # Returns true if equal, otherwise false. [Boolean]
     def ==(other)
       a, b = self.to_f, other.to_f
       a == b
     end
 
@@ -142,11 +166,11 @@
     #
     def digits_encoded
       base_encode(digits)
     end
 
-    #
+    # Returns [String]
     def inspect
       "#{digits.join(' ')} (#{base})"
     end
 
     #
@@ -154,17 +178,21 @@
       [Radix::Rational.new(value), self]  
     end
 
     private
 
+    # Perform operation.
     #
+    # Returns new rational. [Radix::Rational]
     def operation(op, other)
       x = value.__send__(op, other.to_r)
       self.class.new(x, base)
     end
 
+    # Perform base conversion.
     #
+    # Returns array of places. [Array]
     def base_conversion(value, base)
       #if value < 0
       #  @negative, value = true, value.abs
       #end
       i = value.abs
@@ -173,31 +201,38 @@
       while i > 0
         i, r = i.divmod(base)
         a << r
       end
 
+      a << 0 if a.empty?
+
       a.reverse
     end
 
   end
 
 end
 
 class ::Array
   # Convenience method for creating a Radix::Rational.
+  #
   # TODO: Keep #br? Or find another way?
+  #
+  # Returns [Radix::Rational]
   def br(base=nil)
     args = dup
     args << base if base
     Radix::Rational.new(*args)
   end
 end
 
-class ::Float
-  #
-  def to_r
-    n, f = to_s.split('.')
-    d = (10 * f.size).to_i
-    n = (n.to_i * d) + f.to_i
-    Rational(n, d) 
+if RUBY_VERSION < '1.9'
+  class ::Float
+    def to_r
+      n, f = to_s.split('.')
+      d = (10 ** f.size).to_i
+      n = (n.to_i * d) + f.to_i
+      Rational(n, d) 
+    end
   end
 end
+