Class: Musa::Scales::ScaleSystem

Inherits:
Object
  • Object
show all
Defined in:
lib/musa-dsl/music/scales.rb

Direct Known Subclasses

TwelveSemitonesScaleSystem

Class Method Summary collapse

Instance Method Summary collapse

Class Method Details

.[](a_frequency) ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 83

def self.[](a_frequency)
  a_frequency = a_frequency.to_f

  @a_tunings ||= {}
  @a_tunings[a_frequency] = ScaleSystemTuning.new self, a_frequency unless @a_tunings.key?(a_frequency)

  @a_tunings[a_frequency]
end

.chromatic_class ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 123

def self.chromatic_class
  raise "Chromatic scale kind class for [#{self.id}] scale system undefined" if @chromatic_scale_kind_class.nil?

  @chromatic_scale_kind_class
end

.default_a_frequency ⇒ Number

This method is abstract.

Subclass can implement default_a_frequency. If subclass doesn’t implement default_a_frequency 440.0 Hz is assumed.

Returns the frequency A by default.

Returns:

  • (Number) —

    the frequency A by default



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# File 'lib/musa-dsl/music/scales.rb', line 79

def self.default_a_frequency
  440.0
end

.default_tuning ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 96

def self.default_tuning
  self[default_a_frequency]
end

.frequency_of_pitch(pitch, root_pitch, a_frequency) ⇒ Number

This method is abstract.

Subclass is expected to implement frequency_of_pitch

Returns the frequency of the fundamental tone of the pitch.

Parameters:

  • pitch (Number) —

    The pitch (MIDI note numbers based) of the note to get the fundamental frequency

  • root_pitch (Number) —

    The pitch (MIDI note numbers based) of the root note of the scale (needed for not equally tempered scales)

  • a_frequency (Number) —

    The reference frequency of the mid A note

Returns:

  • (Number) —

    the frequency of the fundamental tone of the pitch



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# File 'lib/musa-dsl/music/scales.rb', line 71

def self.frequency_of_pitch(pitch, root_pitch, a_frequency)
  raise 'Method not implemented. Should be implemented in subclass.'
end

.id ⇒ Symbol

This method is abstract.

Subclass is expected to implement names

Returns the id of the ScaleSystem as a symbol.

Returns:

  • (Symbol) —

    the id of the ScaleSystem as a symbol



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# File 'lib/musa-dsl/music/scales.rb', line 33

def self.id
  raise 'Method not implemented. Should be implemented in subclass.'
end

.intervals ⇒ Hash

This method is abstract.

Subclass is expected to implement intervals

Returns the intervals of the ScaleSystem as { name: semitones#, … }.

Returns:

  • (Hash) —

    the intervals of the ScaleSystem as { name: semitones#, … }



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# File 'lib/musa-dsl/music/scales.rb', line 57

def self.intervals
  # TODO: implementar intérvalos sinónimos (p.ej, m3 = A2)
  # TODO: implementar identificación de intérvalos, teniendo en cuenta no sólo los semitonos sino los grados de separación
  # TODO: implementar inversión de intérvalos
  raise 'Method not implemented. Should be implemented in subclass.'
end

.notes_in_octave ⇒ Integer

This method is abstract.

Subclass is expected to implement notes_in_octave

Returns the number of notes in one octave in the ScaleSystem.

Returns:

  • (Integer) —

    the number of notes in one octave in the ScaleSystem



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# File 'lib/musa-dsl/music/scales.rb', line 41

def self.notes_in_octave
  raise 'Method not implemented. Should be implemented in subclass.'
end

.offset_of_interval(name) ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 92

def self.offset_of_interval(name)
  intervals[name]
end

.part_of_tone_size ⇒ Integer

This method is abstract.

Subclass is expected to implement part_of_tone_size

Returns the size inside the ScaleSystem of the smaller part of a tone; used for calculate sharp and flat notes.

Returns:

  • (Integer) —

    the size inside the ScaleSystem of the smaller part of a tone; used for calculate sharp and flat notes



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# File 'lib/musa-dsl/music/scales.rb', line 49

def self.part_of_tone_size
  raise 'Method not implemented. Should be implemented in subclass.'
end

.register(scale_kind_class) ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 100

def self.register(scale_kind_class)
  @scale_kind_classes ||= {}
  @scale_kind_classes[scale_kind_class.id] = scale_kind_class
  if scale_kind_class.chromatic?
    @chromatic_scale_kind_class = scale_kind_class
  end
  self
end

.scale_kind_class(id) ⇒ Object

Raises:

  • (KeyError) 


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# File 'lib/musa-dsl/music/scales.rb', line 109

def self.scale_kind_class(id)
  raise KeyError, "Scale kind class [#{id}] not found in scale system [#{self.id}]" unless @scale_kind_classes.key? id

  @scale_kind_classes[id]
end

.scale_kind_class?(id) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/musa-dsl/music/scales.rb', line 115

def self.scale_kind_class?(id)
  @scale_kind_classes.key? id
end

.scale_kind_classes ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 119

def self.scale_kind_classes
  @scale_kind_classes
end

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 129

def ==(other)
  self.class == other.class
end

#default_a_frequency ⇒ Number

This method is abstract.

Subclass can implement default_a_frequency. If subclass doesn’t implement default_a_frequency 440.0 Hz is assumed.

Returns the frequency A by default.

Returns:

  • (Number) —

    the frequency A by default



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# File 'lib/musa-dsl/music/scales.rb', line 79

def self.default_a_frequency
  440.0
end

#frequency_of_pitch ⇒ Number

This method is abstract.

Subclass is expected to implement frequency_of_pitch

Returns the frequency of the fundamental tone of the pitch.

Parameters:

  • pitch (Number) —

    The pitch (MIDI note numbers based) of the note to get the fundamental frequency

  • root_pitch (Number) —

    The pitch (MIDI note numbers based) of the root note of the scale (needed for not equally tempered scales)

  • a_frequency (Number) —

    The reference frequency of the mid A note

Returns:

  • (Number) —

    the frequency of the fundamental tone of the pitch



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# File 'lib/musa-dsl/music/scales.rb', line 71

def self.frequency_of_pitch(pitch, root_pitch, a_frequency)
  raise 'Method not implemented. Should be implemented in subclass.'
end

#id ⇒ Symbol

This method is abstract.

Subclass is expected to implement names

Returns the id of the ScaleSystem as a symbol.

Returns:

  • (Symbol) —

    the id of the ScaleSystem as a symbol



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# File 'lib/musa-dsl/music/scales.rb', line 33

def self.id
  raise 'Method not implemented. Should be implemented in subclass.'
end

#intervals ⇒ Hash

This method is abstract.

Subclass is expected to implement intervals

Returns the intervals of the ScaleSystem as { name: semitones#, … }.

Returns:

  • (Hash) —

    the intervals of the ScaleSystem as { name: semitones#, … }



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# File 'lib/musa-dsl/music/scales.rb', line 57

def self.intervals
  # TODO: implementar intérvalos sinónimos (p.ej, m3 = A2)
  # TODO: implementar identificación de intérvalos, teniendo en cuenta no sólo los semitonos sino los grados de separación
  # TODO: implementar inversión de intérvalos
  raise 'Method not implemented. Should be implemented in subclass.'
end

#notes_in_octave ⇒ Integer

This method is abstract.

Subclass is expected to implement notes_in_octave

Returns the number of notes in one octave in the ScaleSystem.

Returns:

  • (Integer) —

    the number of notes in one octave in the ScaleSystem



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# File 'lib/musa-dsl/music/scales.rb', line 41

def self.notes_in_octave
  raise 'Method not implemented. Should be implemented in subclass.'
end

#part_of_tone_size ⇒ Integer

This method is abstract.

Subclass is expected to implement part_of_tone_size

Returns the size inside the ScaleSystem of the smaller part of a tone; used for calculate sharp and flat notes.

Returns:

  • (Integer) —

    the size inside the ScaleSystem of the smaller part of a tone; used for calculate sharp and flat notes



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# File 'lib/musa-dsl/music/scales.rb', line 49

def self.part_of_tone_size
  raise 'Method not implemented. Should be implemented in subclass.'
end