Example #1
0
    def testWeightedHexatonicBluesA(self):
        sc = scale.WeightedHexatonicBlues('c4')

        i = 0
        j = 0
        for dummy in range(50):
            # over 50 iterations, it must be one of these two options
            # noinspection PyTypeChecker
            match = self.pitchOut(sc.getPitches('c3', 'c4'))
            if match == '[C3, E-3, F3, G3, B-3, C4]':
                i += 1
            if match == '[C3, E-3, F3, F#3, G3, B-3, C4]':
                j += 1
            self.assertEqual(
                match in [
                    '[C3, E-3, F3, G3, B-3, C4]',
                    '[C3, E-3, F3, F#3, G3, B-3, C4]'
                ], True)
        # check that we got at least one; this may fail rarely
        self.assertGreaterEqual(i, 1)
        self.assertGreaterEqual(j, 1)

        # test descending
        i = 0
        j = 0
        for dummy in range(50):
            # over 50 iterations, it must be one of these two options
            # noinspection PyArgumentList
            match = self.pitchOut(
                sc.getPitches('c3', 'c4', direction=Direction.DESCENDING))
            if match == '[C4, B-3, G3, F3, E-3, C3]':
                i += 1
            if match == '[C4, B-3, G3, F#3, F3, E-3, C3]':
                j += 1
            self.assertEqual(
                match in [
                    '[C4, B-3, G3, F3, E-3, C3]',
                    '[C4, B-3, G3, F#3, F3, E-3, C3]'
                ], True)
        # check that we got at least one; this may fail rarely
        self.assertGreaterEqual(i, 1)
        self.assertGreaterEqual(j, 1)

        self.assertEqual(str(sc.pitchFromDegree(1)), 'C4')
        self.assertEqual(str(sc.nextPitch('c4', Direction.ASCENDING)), 'E-4')

        # degree 4 is always the blues note in this model
        self.assertEqual(str(sc.pitchFromDegree(4)), 'F#4')
Example #2
0
def __generate_scale_tone(lastChord):
    # Derive major or minor scales (minor if 'other') based on the quality
    # of the lastChord.
    scaleType = scale.WeightedHexatonicBlues()  # minor pentatonic
    if lastChord.quality == "major":
        scaleType = scale.MajorScale()
    # Can change later to deriveAll() for flexibility. If so then use list
    # comprehension of form [x for a in b for x in a].
    scales = scaleType.derive(
        lastChord)  # use deriveAll() later for flexibility
    allPitches = list(set([pitch for pitch in scales.getPitches()]))
    allNoteNames = [i.name for i in allPitches]  # octaves don't matter

    # Return a note (no octave here) in a scale that matches the lastChord.
    sNoteName = random.choice(allNoteNames)
    lastChordSort = lastChord.sortAscending()
    sNoteOctave = random.choice([i.octave for i in lastChordSort.pitches])
    sNote = note.Note(("%s%s" % (sNoteName, sNoteOctave)))
    return sNote
Example #3
0
    def testIntervalBetweenDegrees(self):
        sc = scale.MajorScale('c4')
        self.assertEqual(str(sc.intervalBetweenDegrees(3, 4)),
                         '<music21.interval.Interval m2>')
        self.assertEqual(str(sc.intervalBetweenDegrees(1, 7)),
                         '<music21.interval.Interval M7>')
        self.assertEqual(str(sc.intervalBetweenDegrees(1, 5)),
                         '<music21.interval.Interval P5>')
        self.assertEqual(str(sc.intervalBetweenDegrees(2, 4)),
                         '<music21.interval.Interval m3>')

        # with a probabilistic non-deterministic scale,
        # an exception may be raised for step that may not exist
        sc = scale.WeightedHexatonicBlues('g3')
        exceptCount = 0
        for dummy in range(10):
            post = None
            try:
                post = sc.intervalBetweenDegrees(3, 4)
            except scale.ScaleException:
                exceptCount += 1
            if post is not None:
                self.assertEqual(str(post), '<music21.interval.Interval A1>')
        self.assertLess(exceptCount, 3)
Example #4
0
    def testScales01(self):
        from music21 import pitch

        #==== "fig-py01"

        # Providing a tonic makes this concrete
        sc1 = scale.MajorScale('g4')
        sc2 = scale.MajorScale('e-3')

        # Comparing Concrete and Abstract Scales
        assert (sc1 == sc2) == False
        assert (sc1.abstract == sc2.abstract) == True

        # Without arguments, getPitches() returns a single span
        assert common.pitchList(
            sc1.getPitches()) == '[G4, A4, B4, C5, D5, E5, F#5, G5]'
        assert common.pitchList(sc2.getPitches(
            'c2', 'c3')) == '[C2, D2, E-2, F2, G2, A-2, B-2, C3]'

        # As a Chord, Scale pitches gain additional functionality
        assert sc1.getChord().forteClass == '7-35'

        # Given a degree, get the pitch
        assert str(sc1.pitchFromDegree(5)) == 'D5'
        assert common.pitchList(
            sc2.pitchesFromScaleDegrees([7, 2], 'e-6',
                                        'e-9')) == '[F6, D7, F7, D8, F8, D9]'

        # Get a scale degree from a pitch
        assert sc1.getScaleDegreeFromPitch('d') == 5
        assert sc2.getScaleDegreeFromPitch('d') == 7

        # Get the next pitch given step directions
        match = [pitch.Pitch('g2')]
        for direction in [1, 1, 1, -2, 4, -1, 1, 1, 1]:
            # Append the next pitch based on the last-added pitch
            match.append(sc1.next(match[-1], direction))
        assert common.pitchList(
            match), '[G2, A2, B2, C3, A2, E3, D3, E3, F#3, G3]'

        # Derive new scales based on a provided collection or degree
        assert str(sc1.derive(['c4', 'g4', 'b8',
                               'f2'])) == '<music21.scale.MajorScale C major>'
        assert str(sc1.deriveByDegree(
            7, 'C#')) == '<music21.scale.MajorScale D major>'

        # Methods unique to DiatonicScale subclasses
        assert str(
            sc2.getRelativeMinor()) == '<music21.scale.MinorScale C minor>'
        #==== "fig-py01" end

        #==== "fig-py02"
        sc1 = scale.PhrygianScale('g4')
        assert common.pitchList(
            sc1.getPitches()) == '[G4, A-4, B-4, C5, D5, E-5, F5, G5]'
        assert str(
            sc1.getRelativeMajor()) == '<music21.scale.MajorScale E- major>'
        assert str(sc1.getTonic()), str(sc1.getDominant()) == ('G4', 'D5')

        sc2 = scale.HypodorianScale('a6')
        assert common.pitchList(sc2.getPitches(
            'e2', 'e3')) == '[E2, F#2, G2, A2, B2, C3, D3, E3]'
        assert str(
            sc2.getRelativeMajor()) == '<music21.scale.MajorScale G major>'
        assert str(sc2.getTonic()), str(sc2.getDominant()) == ('A6', 'C7')

        #==== "fig-py02" end

        #==== "fig-py06"
        # see below
        #==== "fig-py06" end

        #==== "fig-py03"
        #print('\n\nfig-py03')

        sc1 = scale.HarmonicMinorScale('a3')
        assert common.pitchList(
            sc1.getPitches()) == '[A3, B3, C4, D4, E4, F4, G#4, A4]'
        assert str(sc1.getTonic()), str(sc1.getDominant()) == ('A3', 'E4')

        s = stream.Stream()
        for d in [1, 3, 2, 1, 6, 5, 8, 7, 8]:
            s.append(
                note.Note(sc1.pitchFromDegree(d, equateTermini=False),
                          type='eighth'))
        #s.show()
        #==== "fig-py03" end

        #==== "fig-py04"
        import random

        sc1 = scale.MelodicMinorScale('c4')
        assert common.pitchList(sc1.getPitches(
            direction='ascending')) == '[C4, D4, E-4, F4, G4, A4, B4, C5]'
        assert common.pitchList(
            sc1.getPitches('c3', 'c5', direction='descending')) == (
                '[C5, B-4, A-4, G4, F4, E-4, D4, ' +
                'C4, B-3, A-3, G3, F3, E-3, D3, C3]')
        assert str(sc1.getTonic()), str(sc1.getDominant()) == ('C4', 'G4')

        s = stream.Stream()
        p = None
        for i in range(8):  # was 16, but sometimes exceeded scale length.
            direction = random.choice([-1, 1])
            for j in range(2):
                p = sc1.next(p, direction)
                s.append(note.Note(p, quarterLength=.25))
        #s.show()
        #==== "fig-py04" end

        #==== "fig-py05"
        sc1 = scale.OctatonicScale('e3', 'm2')
        assert common.pitchList(
            sc1.getPitches()) == '[E3, F3, G3, A-3, B-3, C-4, D-4, D4, E4]'
        sc2 = scale.OctatonicScale('e3', 'M2')
        assert common.pitchList(
            sc2.getPitches()) == '[E3, F#3, G3, A3, B-3, C4, D-4, E-4, F-4]'

        part1 = stream.Part()
        part2 = stream.Part()
        durPart1 = [1, 1, 0.5, 0.5, 1]
        durPart2 = [3, 1]
        degrees = list(range(1, 9))
        for unused in range(4):
            random.shuffle(degrees)
            random.shuffle(durPart1)
            random.shuffle(durPart2)
            i = 0
            for dur in durPart1:
                part1.append(
                    note.Note(sc2.pitchFromDegree(degrees[i]),
                              quarterLength=dur))
                i += 1
            for dur in durPart2:
                part2.append(
                    note.Note(sc2.pitchFromDegree(degrees[i],
                                                  minPitch='c2',
                                                  maxPitch='c3'),
                              quarterLength=dur))
                i += 1
        s = stream.Score()
        s.insert(0, part1)
        s.insert(0, part2)
        #s.show()

        # add notation example; perhaps create tri-chords from scale-completing selections
        #==== "fig-py05" end

        #sc = scale.SieveScale('c2', '(-3@2 & 4) | (-3@1 & 4@1) | (3@2 & 4@2) | (-3 & 4@3)')

        #==== "fig-py07"
        # add examples
        sc1 = scale.SieveScale('c4', '3@0|4@0')
        self.assertEqual(common.pitchList(sc1.getPitches()),
                         '[C4, E-4, E4, F#4, G#4, A4, C5]')

        sc2 = scale.SieveScale('c4', '5@0|7@0')
        self.assertEqual(
            common.pitchList(sc2.getPitches()),
            '[C4, F4, G4, B-4, D5, E-5, G#5, A5, C#6, E6, F#6, B6]')

        s = stream.Stream()
        pColection = sc2.getPitches('c3', 'c7')
        random.shuffle(pColection)
        for p in pColection:
            s.append(note.Note(p, type='16th'))
        #s.show()
        #==== "fig-py07" end

        #==== "fig-py08"

        sc1 = scale.RagAsawari('g3')
        self.assertEqual(
            common.pitchList(sc1.getPitches(direction='ascending')),
            '[G3, A3, C4, D4, E-4, G4]')
        self.assertEqual(
            common.pitchList(sc1.getPitches(direction='descending')),
            '[G4, F4, E-4, D4, C4, B-3, A3, G3]')

        sc2 = scale.RagMarwa('g3')
        assert common.pitchList(sc2.getPitches(direction='ascending')
                                ) == '[G3, A-3, B3, C#4, E4, F#4, E4, G4, A-4]'
        assert common.pitchList(
            sc2.getPitches(direction='descending'
                           )) == '[A-4, G4, A-4, F#4, E4, C#4, B3, A-3, G3]'

        p1 = None
        s = stream.Stream()
        for direction in ([1] * 10) + ([-1] * 8) + ([1] * 4) + ([-1] *
                                                                3) + ([1] * 4):
            p1 = sc1.next(p1, direction)
            s.append(note.Note(p1, quarterLength=.25))
        #s.show()

        p1 = None
        s = stream.Stream()
        for direction in ([1] * 10) + ([-1] * 8) + ([1] * 4) + ([-1] *
                                                                3) + ([1] * 4):
            p1 = sc2.next(p1, direction)
            s.append(note.Note(p1, quarterLength=.25))
        #s.show()

        #==== "fig-py08" end

        #==== "fig-py09"
        #import random
        sc1 = scale.WeightedHexatonicBlues('c3')
        p = 'c3'
        s = stream.Stream()
        for n in range(32):
            p = sc1.next(p, random.choice([-1, 1]))
            n = note.Note(p, quarterLength=random.choice([.5, .25, .25]))
            s.append(n)