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-rw-r--r--ruby_1_8_6/ext/bigdecimal/lib/bigdecimal/util.rb65
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diff --git a/ruby_1_8_6/ext/bigdecimal/lib/bigdecimal/util.rb b/ruby_1_8_6/ext/bigdecimal/lib/bigdecimal/util.rb
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+#
+# BigDecimal utility library.
+#
+# To use these functions, require 'bigdecimal/util'
+#
+# The following methods are provided to convert other types to BigDecimals:
+#
+# String#to_d -> BigDecimal
+# Float#to_d -> BigDecimal
+# Rational#to_d -> BigDecimal
+#
+# The following method is provided to convert BigDecimals to other types:
+#
+# BigDecimal#to_r -> Rational
+#
+# ----------------------------------------------------------------------
+#
+class Float < Numeric
+ def to_d
+ BigDecimal(self.to_s)
+ end
+end
+
+class String
+ def to_d
+ BigDecimal(self)
+ end
+end
+
+class BigDecimal < Numeric
+ # Converts a BigDecimal to a String of the form "nnnnnn.mmm".
+ # This method is deprecated; use BigDecimal#to_s("F") instead.
+ def to_digits
+ if self.nan? || self.infinite? || self.zero?
+ self.to_s
+ else
+ i = self.to_i.to_s
+ s,f,y,z = self.frac.split
+ i + "." + ("0"*(-z)) + f
+ end
+ end
+
+ # Converts a BigDecimal to a Rational.
+ def to_r
+ sign,digits,base,power = self.split
+ numerator = sign*digits.to_i
+ denomi_power = power - digits.size # base is always 10
+ if denomi_power < 0
+ Rational(numerator,base ** (-denomi_power))
+ else
+ Rational(numerator * (base ** denomi_power),1)
+ end
+ end
+end
+
+class Rational < Numeric
+ # Converts a Rational to a BigDecimal
+ 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