Module: RomanNumerals

Included in:
NumberTo
Defined in:
lib/modules/roman_numerals.rb

Overview

adapted without any substanial changes from github.com/AndrewVos/roman-numerals

Constant Summary collapse

BASE_DIGITS = 
{
  1 => 'I',
  4 => 'IV',
  5 => 'V',
  9 => 'IX',
  10 => 'X',
  40 => 'XL',
  50 => 'L',
  90 => 'XC',
  100 => 'C',
  400 => 'CD',
  500 => 'D',
  900 => 'CM',
  1000 => 'M'
}

Instance Method Summary collapse

Instance Method Details

#to_lower_roman(value) ⇒ Object 



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# File 'lib/modules/roman_numerals.rb', line 30

def to_lower_roman(value)
  to_upper_roman(value).downcase
end

#to_upper_roman(value) ⇒ Object 



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# File 'lib/modules/roman_numerals.rb', line 19

def to_upper_roman(value)
  result = ''
  BASE_DIGITS.keys.reverse.each do |decimal|
    while value >= decimal
      value -= decimal
      result += BASE_DIGITS[decimal]
    end
  end
  result
end