#
# 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
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