Method: Coltrane::Theory::Interval#initialize

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

#initialize(arg_1 = nil, arg_2 = nil, ascending: true, letter_distance: nil, semitones: nil, compound: false) ⇒ Interval

Returns a new instance of Interval.



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# File 'lib/coltrane/theory/interval.rb', line 40

def initialize(arg_1 = nil, arg_2 = nil, ascending: true,
               letter_distance: nil,
               semitones: nil,
               compound: false)
  if arg_1 && !arg_2 # assumes arg_1 is a letter
    @compound = compound
    IntervalClass[arg_1].interval.yield_self do |interval|
      @letter_distance = interval.letter_distance
      @cents = interval.cents
    end
  elsif arg_1 && arg_2 # assumes those are notes
    if ascending
      @compound = compound
      @cents =
        (arg_1.frequency / arg_2.frequency)
        .interval_class
        .cents

      @letter_distance = calculate_letter_distance arg_1.letter,
                                                   arg_2.letter,
                                                   ascending
    else
      self.class.new(arg_1, arg_2).descending.yield_self do |base_interval|
        @compound        = base_interval.compound?
        @cents           = base_interval.cents
        @letter_distance = base_interval.letter_distance
      end
    end
  elsif letter_distance && semitones
    @compound        = compound || letter_distance > 8
    @cents           = semitones * 100
    @letter_distance = letter_distance
  else
    raise WrongKeywordsError,
          '[interval_class_name]' \
          'Provide: [first_note, second_note] || ' \
          '[letter_distance:, semitones:]'
  end
end