Module: BCD

Defined in:
lib/bcd.rb

Overview

Methods to translate to and from binary coded decimal

Author

David Crosby <[email protected]>

Copyright

Copyright 2013-2022 David Crosby

License

BSD 2-clause

Class Method Summary collapse

Class Method Details

.decode(bcd) ⇒ Object

Translates binary coded decimal into an integer : (Integer) -> Integer

Raises:

  • (ArgumentError) 


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# File 'lib/bcd.rb', line 14

def self.decode(bcd)
  raise ArgumentError, "Argument is not Integer" unless bcd.is_a? Integer
  raise ArgumentError, "Cannot be a negative integer" if bcd.negative?

  binstring = String.new
  loop do
    q, r = bcd.divmod(10)
    nibble = r.to_s(2)
    nibble.prepend("0") while nibble.length < 4
    binstring.prepend(nibble)
    q.zero? ? break : bcd = q
  end

  binstring.to_i(2)
end

.encode(int) ⇒ Object

Translate an integer into binary coded decimal : (Integer) -> Integer

Raises:

  • (ArgumentError) 


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# File 'lib/bcd.rb', line 32

def self.encode(int)
  raise ArgumentError, "Argument is not Integer" unless int.is_a? Integer
  raise ArgumentError, "Cannot be a negative integer" if int.negative?

  bcdstring = String.new
  while int.positive?
    nibble = int % 16
    bcdstring.prepend(nibble.to_s)
    int >>= 4
  end
  bcdstring.to_i
end