Class: QrCodeMaker::QRPolynomial

Inherits:
Object
  • Object
show all
Defined in:
lib/qr_code_maker/encoder.rb

Instance Method Summary collapse

Constructor Details

#initialize(num, shift) ⇒ QRPolynomial

Returns a new instance of QRPolynomial.

Raises:



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# File 'lib/qr_code_maker/encoder.rb', line 112

def initialize(num, shift)
  raise QRCodeRunTimeError, "#{num.size}/#{shift}" if num.empty?
  offset = 0

  while offset < num.size && num[offset] == 0
    offset += 1
  end

  @num = Array.new(num.size - offset + shift)

  (0...num.size - offset).each do |i|
    @num[i] = num[i + offset]
  end
end

Instance Method Details

#get(index) ⇒ Object 



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# File 'lib/qr_code_maker/encoder.rb', line 127

def get(index)
  @num[index]
end

#get_length ⇒ Object 



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# File 'lib/qr_code_maker/encoder.rb', line 131

def get_length
  @num.size
end

#mod(e) ⇒ Object 



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# File 'lib/qr_code_maker/encoder.rb', line 148

def mod(e)
  if get_length - e.get_length < 0
    return self
  end

  ratio = QRMath.glog(get(0)) - QRMath.glog(e.get(0))
  num = Array.new(get_length)

  (0...get_length).each do |i|
    num[i] = get(i)
  end

  (0...e.get_length).each do |i|
    tmp = num[i].nil? ? 0 : num[i]
    num[i] = tmp ^ QRMath.gexp(QRMath.glog(e.get(i)) + ratio)
  end

  QRPolynomial.new(num, 0).mod(e)
end

#multiply(e) ⇒ Object 



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# File 'lib/qr_code_maker/encoder.rb', line 135

def multiply(e)
  num = Array.new(get_length + e.get_length - 1)

  (0...get_length).each do |i|
    (0...e.get_length).each do |j|
      tmp = num[i + j].nil? ? 0 : num[i + j]
      num[i + j] = tmp ^ QRMath.gexp(QRMath.glog(get(i)) + QRMath.glog(e.get(j)))
    end
  end

  QRPolynomial.new(num, 0)
end