1 files changed, 30 insertions, 0 deletions
diff --git a/ext/bigdecimal/lib/bigdecimal-rational.rb b/ext/bigdecimal/lib/bigdecimal-rational.rb
new file mode 100644
index 0000000000..de999d19cf
--- /dev/null
+++ b/ext/bigdecimal/lib/bigdecimal-rational.rb
@@ -0,0 +1,30 @@
+#
+# BigDecimal <-> Rational 
+#
+class BigDecimal
+    # Convert BigDecimal to Rational
+    def to_r 
+       sign,digits,base,power = self.to_parts
+       numerator = sign*digits.to_i
+       denomi_power = power - digits.size # base is always 10
+       if denomi_power < 0
+          denominator = base ** (-denomi_power)
+       else
+          denominator = base ** denomi_power
+       end
+       Rational.new(numerator,denominator)
+    end
+end
+
+class Rational
+  # Convert Rational to BigDecimal
+  # to_d returns an array [quotient,residue]
+  def to_d(nFig=0)
+     num = self.numerator.to_s
+     if nFig<=0
+        nFig = BigDecimal.double_fig*2+1
+     end
+     BigDecimal.new(num).div(self.denominator,nFig)
+  end
+end
+