diff options
Diffstat (limited to 'ruby_1_8_5/ext/bigdecimal/lib/bigdecimal/util.rb')
-rw-r--r-- | ruby_1_8_5/ext/bigdecimal/lib/bigdecimal/util.rb | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/ruby_1_8_5/ext/bigdecimal/lib/bigdecimal/util.rb b/ruby_1_8_5/ext/bigdecimal/lib/bigdecimal/util.rb new file mode 100644 index 0000000000..09e926acd5 --- /dev/null +++ b/ruby_1_8_5/ext/bigdecimal/lib/bigdecimal/util.rb @@ -0,0 +1,65 @@ +# +# 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 |