Method: Coltrane::Theory::Note#initialize

Defined in:
lib/coltrane/theory/note.rb

#initialize(arg) ⇒ Note

Returns a new instance of Note.

Raises:



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# File 'lib/coltrane/theory/note.rb', line 24

def initialize(arg)
  note_name = case arg
              when String then arg
              when PitchClass then arg.true_notation
              when Numeric, Frequency then PitchClass.new(arg).true_notation
              else raise(WrongArgumentsError, arg)
              end

  chars  = note_name.chars
  letter = chars.shift
  raise InvalidNoteLetterError, arg unless ('A'..'G').cover?(letter)
  @alteration = chars.reduce(0) do |alt, symbol|
    raise InvalidNoteLetterError, arg unless ALTERATIONS.include?(symbol)
    alt + ALTERATIONS[symbol]
  end
  super((PitchClass[letter].integer + @alteration) % PitchClass.size)
end