Class: Musa::Scales::ScaleKind

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

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(tuning) ⇒ ScaleKind

Returns a new instance of ScaleKind.



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# File 'lib/musa-dsl/music/scales.rb', line 185

def initialize(tuning)
  @tuning = tuning
  @scales = {}
end

Instance Attribute Details

#tuning ⇒ Object (readonly)

Returns the value of attribute tuning.



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# File 'lib/musa-dsl/music/scales.rb', line 190

def tuning
  @tuning
end

Class Method Details

.chromatic? ⇒ Boolean

This method is abstract.

Subclass is expected to implement chromatic?. Only one of the subclasses should return true.

Returns wether the scales is a full scale (with all the notes in the ScaleSystem), sorted and to be considered canonical. I.e. a chromatic 12 semitones uprising serie in a 12 tone tempered ScaleSystem.

Returns:

  • (Boolean) —

    wether the scales is a full scale (with all the notes in the ScaleSystem), sorted and to be considered canonical. I.e. a chromatic 12 semitones uprising serie in a 12 tone tempered ScaleSystem.



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# File 'lib/musa-dsl/music/scales.rb', line 228

def self.chromatic?
  false
end

.grade_of_function(symbol) ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 239

def self.grade_of_function(symbol)
  create_grade_functions_index unless @grade_names_index
  @grade_names_index[symbol]
end

.grades ⇒ Integer

This method is abstract.

Subclass is expected to implement grades when the ScaleKind is defining more pitches than notes by octave has the scale. This can happen when there are pitches defined on upper octaves (i.e., to define XII grade, as a octave + fifth)

Returns Number of grades inside of a octave of the scale.

Returns:

  • (Integer) —

    Number of grades inside of a octave of the scale



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# File 'lib/musa-dsl/music/scales.rb', line 235

def self.grades
  pitches.length
end

.grades_functions ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 244

def self.grades_functions
  create_grade_functions_index unless @grade_names_index
  @grade_names_index.keys
end

.id ⇒ Symbol

This method is abstract.

Subclass is expected to implement id

Returns the id of the ScaleKind as a symbol.

Returns:

  • (Symbol) —

    the id of the ScaleKind as a symbol



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# File 'lib/musa-dsl/music/scales.rb', line 214

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

.pitches ⇒ Array

This method is abstract.

Subclass is expected to implement pitches

Returns the pitches array of the ScaleKind as [ { functions: [ <symbol>, …], pitch: <Number> }, … ].

Returns:

  • (Array) —

    the pitches array of the ScaleKind as [ { functions: [ <symbol>, …], pitch: <Number> }, … ]



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# File 'lib/musa-dsl/music/scales.rb', line 221

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

Instance Method Details

#==(other) ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 201

def ==(other)
  self.class == other.class && @tuning == other.tuning
end

#[](root_pitch) ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 192

def [](root_pitch)
  @scales[root_pitch] = Scale.new(self, root_pitch: root_pitch) unless @scales.key?(root_pitch)
  @scales[root_pitch]
end

#absolut ⇒ Object 



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# File 'lib/musa-dsl/music/scales.rb', line 197

def absolut
  self[0]
end

#chromatic? ⇒ Boolean

This method is abstract.

Subclass is expected to implement chromatic?. Only one of the subclasses should return true.

Returns wether the scales is a full scale (with all the notes in the ScaleSystem), sorted and to be considered canonical. I.e. a chromatic 12 semitones uprising serie in a 12 tone tempered ScaleSystem.

Returns:

  • (Boolean) —

    wether the scales is a full scale (with all the notes in the ScaleSystem), sorted and to be considered canonical. I.e. a chromatic 12 semitones uprising serie in a 12 tone tempered ScaleSystem.



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# File 'lib/musa-dsl/music/scales.rb', line 228

def self.chromatic?
  false
end

#grades ⇒ Integer

This method is abstract.

Subclass is expected to implement grades when the ScaleKind is defining more pitches than notes by octave has the scale. This can happen when there are pitches defined on upper octaves (i.e., to define XII grade, as a octave + fifth)

Returns Number of grades inside of a octave of the scale.

Returns:

  • (Integer) —

    Number of grades inside of a octave of the scale



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# File 'lib/musa-dsl/music/scales.rb', line 235

def self.grades
  pitches.length
end

#id ⇒ Symbol

This method is abstract.

Subclass is expected to implement id

Returns the id of the ScaleKind as a symbol.

Returns:

  • (Symbol) —

    the id of the ScaleKind as a symbol



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# File 'lib/musa-dsl/music/scales.rb', line 214

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

#inspect ⇒ Object Also known as: to_s 



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# File 'lib/musa-dsl/music/scales.rb', line 205

def inspect
  "<#{self.class.name}: tuning = #{@tuning}>"
end

#pitches ⇒ Array

This method is abstract.

Subclass is expected to implement pitches

Returns the pitches array of the ScaleKind as [ { functions: [ <symbol>, …], pitch: <Number> }, … ].

Returns:

  • (Array) —

    the pitches array of the ScaleKind as [ { functions: [ <symbol>, …], pitch: <Number> }, … ]



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# File 'lib/musa-dsl/music/scales.rb', line 221

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