music21.features.native¶

Original music21 feature extractors.

ChordBassMotionFeature¶

class music21.features.native.ChordBassMotionFeature(dataOrStream=None, **keywords)¶

A twelve element feature that reports the fraction of all chord motion of music21.harmony.Harmony objects that move up by i-half-steps. (a half-step motion down would be stored in i = 11). i = 0 is always 0.0 since consecutive chords on the same pitch are ignored (unless there are 0 or 1 harmonies, in which case it is 1)

Sample test on Dylan’s Blowing In The Wind (not included), showing all motion is 3rds, 6ths, or especially 4ths and 5ths.

s = corpus.parse(‘demos/BlowinInTheWind’) fe = features.native.ChordBassMotionFeature(s) fe.extract().vector

[0.0, 0.0, 0.0, 0.0416…, 0.0416…, 0.166…, 0.0, 0.54166…, 0.0, 0.0, 0.2083… 0.0]

For comparison, the Beatles Here Comes the Sun has more tone motion

[0.0, 0.05…, 0.14…, 0.03…, 0.06…, 0.3…, 0.008…, 0.303…,: 0.0, 0.0, 0.07…, 0.008…]

Post 1990s music has a lot more semitone motion.

ChordBassMotionFeature bases

FeatureExtractor

ChordBassMotionFeature methods

ChordBassMotionFeature.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

ComposerPopularity¶

class music21.features.native.ComposerPopularity(dataOrStream=None, **keywords)¶: REMOVED in v7 because Google’s repsonse no longer includes result counts. Empty class still here so that id won’t be reused, but it’s been removed from this module’s list of features.

ComposerPopularity bases

FeatureExtractor

ComposerPopularity methods

Methods inherited from FeatureExtractor:

DiminishedSeventhSimultaneityPrevalence¶

class music21.features.native.DiminishedSeventhSimultaneityPrevalence(dataOrStream=None, **keywords)¶

Percentage of all simultaneities that are diminished seventh chords.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.DiminishedSeventhSimultaneityPrevalence(s)
>>> fe.extract().vector
[0.0]

DiminishedSeventhSimultaneityPrevalence bases

FeatureExtractor

DiminishedSeventhSimultaneityPrevalence methods

DiminishedSeventhSimultaneityPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

DiminishedTriadSimultaneityPrevalence¶

class music21.features.native.DiminishedTriadSimultaneityPrevalence(dataOrStream=None, **keywords)¶

Percentage of all simultaneities that are diminished triads.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.DiminishedTriadSimultaneityPrevalence(s)
>>> fe.extract().vector
[0.019...]

DiminishedTriadSimultaneityPrevalence bases

FeatureExtractor

DiminishedTriadSimultaneityPrevalence methods

DiminishedTriadSimultaneityPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

DominantSeventhSimultaneityPrevalence¶

class music21.features.native.DominantSeventhSimultaneityPrevalence(dataOrStream=None, **keywords)¶

Percentage of all simultaneities that are dominant seventh.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.DominantSeventhSimultaneityPrevalence(s)
>>> fe.extract().vector
[0.076...]

DominantSeventhSimultaneityPrevalence bases

FeatureExtractor

DominantSeventhSimultaneityPrevalence methods

DominantSeventhSimultaneityPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

FirstBeatAttackPrevalence¶

class music21.features.native.FirstBeatAttackPrevalence(dataOrStream=None, **keywords)¶

NOT IMPLEMENTED!

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.FirstBeatAttackPrevalence(s)
>>> f = fe.extract()
>>> f.vector
[0]

TODO: Implement!

FirstBeatAttackPrevalence bases

FeatureExtractor

FirstBeatAttackPrevalence methods

Methods inherited from FeatureExtractor:

IncorrectlySpelledTriadPrevalence¶

class music21.features.native.IncorrectlySpelledTriadPrevalence(dataOrStream=None, **keywords)¶

Percentage of all triads that are spelled incorrectly.

example:

Mozart k155 movement 2 has a single instance of an incorrectly spelled triad (m. 17, where the C# of an A-major chord has a lower neighbor B# thus temporarily creating an incorrectly spelled A-minor chord).

We would expect highly chromatic music such as Reger or Wagner to have a higher percentage, or automatically rendered MIDI transcriptions (which don’t distinguish between D# and Eb).

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.IncorrectlySpelledTriadPrevalence(s)
>>> fe.extract().vector
[0.02...]

IncorrectlySpelledTriadPrevalence bases

FeatureExtractor

IncorrectlySpelledTriadPrevalence methods

IncorrectlySpelledTriadPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

LandiniCadence¶

class music21.features.native.LandiniCadence(dataOrStream=None, **keywords)¶: Return a boolean if one or more Parts end with a Landini-like cadential figure.

LandiniCadence bases

FeatureExtractor

LandiniCadence methods

LandiniCadence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

LanguageFeature¶

class music21.features.native.LanguageFeature(dataOrStream=None, **keywords)¶

language of text as a number the number is the index of text.LanguageDetector.languageCodes + 1 or 0 if there is no language.

Detect that the language of a Handel aria is Italian.

>>> s = corpus.parse('handel/rinaldo/lascia_chio_pianga')
>>> fe = features.native.LanguageFeature(s)
>>> fe.extract().vector
[3]

LanguageFeature bases

FeatureExtractor

LanguageFeature methods

LanguageFeature.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

MajorTriadSimultaneityPrevalence¶

class music21.features.native.MajorTriadSimultaneityPrevalence(dataOrStream=None, **keywords)¶

Percentage of all simultaneities that are major triads.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.MajorTriadSimultaneityPrevalence(s)
>>> fe.extract().vector
[0.46...]

MajorTriadSimultaneityPrevalence bases

FeatureExtractor

MajorTriadSimultaneityPrevalence methods

MajorTriadSimultaneityPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

MinorTriadSimultaneityPrevalence¶

class music21.features.native.MinorTriadSimultaneityPrevalence(dataOrStream=None, **keywords)¶

Percentage of all simultaneities that are minor triads.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.MinorTriadSimultaneityPrevalence(s)
>>> fe.extract().vector  # same as major in this work
[0.211...]

MinorTriadSimultaneityPrevalence bases

FeatureExtractor

MinorTriadSimultaneityPrevalence methods

MinorTriadSimultaneityPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

MostCommonNoteQuarterLength¶

class music21.features.native.MostCommonNoteQuarterLength(dataOrStream=None, **keywords)¶

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.MostCommonNoteQuarterLength(s)
>>> fe.extract().vector
[1.0]

MostCommonNoteQuarterLength bases

FeatureExtractor

MostCommonNoteQuarterLength methods

MostCommonNoteQuarterLength.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

MostCommonNoteQuarterLengthPrevalence¶

class music21.features.native.MostCommonNoteQuarterLengthPrevalence(dataOrStream=None, **keywords)¶

Fraction of notes that have the most common quarter length.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.MostCommonNoteQuarterLengthPrevalence(s)
>>> fe.extract().vector
[0.60...]

MostCommonNoteQuarterLengthPrevalence bases

FeatureExtractor

MostCommonNoteQuarterLengthPrevalence methods

MostCommonNoteQuarterLengthPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

MostCommonPitchClassSetSimultaneityPrevalence¶

class music21.features.native.MostCommonPitchClassSetSimultaneityPrevalence(dataOrStream=None, **keywords)¶

Fraction of all pitch class simultaneities that are the most common simultaneity.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.MostCommonPitchClassSetSimultaneityPrevalence(s)
>>> fe.extract().vector
[0.134...]

MostCommonPitchClassSetSimultaneityPrevalence bases

FeatureExtractor

MostCommonPitchClassSetSimultaneityPrevalence methods

MostCommonPitchClassSetSimultaneityPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

MostCommonSetClassSimultaneityPrevalence¶

class music21.features.native.MostCommonSetClassSimultaneityPrevalence(dataOrStream=None, **keywords)¶

Fraction of all set class simultaneities that the most common simultaneity occupies.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.MostCommonSetClassSimultaneityPrevalence(s)
>>> fe.extract().vector
[0.653...]
>>> s2 = corpus.parse('schoenberg/opus19', 6)
>>> fe2 = features.native.MostCommonSetClassSimultaneityPrevalence(s2)
>>> fe2.extract().vector
[0.235...]

MostCommonSetClassSimultaneityPrevalence bases

FeatureExtractor

MostCommonSetClassSimultaneityPrevalence methods

MostCommonSetClassSimultaneityPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

QualityFeature¶

class music21.features.native.QualityFeature(dataOrStream=None, **keywords)¶

Extends the jSymbolic QualityFeature to automatically find mode.

Set to 0 if the key signature indicates that a recording is major, set to 1 if it indicates that it is minor. A Music21 addition: if no key mode is found in the piece, or conflicting modes in the keys, analyze the piece to discover what mode it is most likely in.

Example: Handel, Rinaldo Aria (musicxml) is explicitly encoded as being in Major:

>>> s = corpus.parse('handel/rinaldo/lascia_chio_pianga')
>>> fe = features.native.QualityFeature(s)
>>> f = fe.extract()
>>> f.vector
[0]

now we will try it with the last movement of Schoenberg’s opus 19 which has no mode explicitly encoded in the musicxml but which our analysis routines believe (having very little to go on) fits the profile of e minor best.

>>> schoenberg19mvmt6 = corpus.parse('schoenberg/opus19', 6)
>>> fe2 = features.native.QualityFeature(schoenberg19mvmt6)
>>> f2 = fe2.extract()
>>> f2.vector
[1]

QualityFeature bases

FeatureExtractor

QualityFeature methods

QualityFeature.process() → None¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

RangeOfNoteQuarterLengths¶

class music21.features.native.RangeOfNoteQuarterLengths(dataOrStream=None, **keywords)¶

Difference between the longest and shortest quarter lengths.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.RangeOfNoteQuarterLengths(s)
>>> fe.extract().vector
[1.5]

RangeOfNoteQuarterLengths bases

FeatureExtractor

RangeOfNoteQuarterLengths methods

RangeOfNoteQuarterLengths.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

TonalCertainty¶

class music21.features.native.TonalCertainty(dataOrStream=None, **keywords)¶

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.TonalCertainty(s)
>>> f = fe.extract()
>>> f.vector
[1.26...]

>>> pitches = [56, 55, 56, 57, 58, 57, 58, 59, 60, 59, 60, 61, 62, 61,
...            62, 63, 64, 63, 64, 65, 66, 65, 66, 67]
>>> s = stream.Stream()
>>> for pitch in pitches:
...   s.append(note.Note(pitch))
>>> features.native.TonalCertainty(s).extract().vector
[0.0]

TonalCertainty bases

FeatureExtractor

TonalCertainty methods

TonalCertainty.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

TriadSimultaneityPrevalence¶

class music21.features.native.TriadSimultaneityPrevalence(dataOrStream=None, **keywords)¶

Gives the proportion of all simultaneities which form triads (major, minor, diminished, or augmented)

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.TriadSimultaneityPrevalence(s)
>>> fe.extract().vector
[0.692...]
>>> s2 = corpus.parse('schoenberg/opus19', 2)
>>> fe2 = features.native.TriadSimultaneityPrevalence(s2)
>>> fe2.extract().vector
[0.02272727...]

TriadSimultaneityPrevalence bases

FeatureExtractor

TriadSimultaneityPrevalence methods

TriadSimultaneityPrevalence.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

UniqueNoteQuarterLengths¶

class music21.features.native.UniqueNoteQuarterLengths(dataOrStream=None, **keywords)¶

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.UniqueNoteQuarterLengths(s)
>>> fe.extract().vector
[3]

UniqueNoteQuarterLengths bases

FeatureExtractor

UniqueNoteQuarterLengths methods

UniqueNoteQuarterLengths.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

UniquePitchClassSetSimultaneities¶

class music21.features.native.UniquePitchClassSetSimultaneities(dataOrStream=None, **keywords)¶

Number of unique pitch class simultaneities.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.UniquePitchClassSetSimultaneities(s)
>>> fe.extract().vector
[27]

UniquePitchClassSetSimultaneities bases

FeatureExtractor

UniquePitchClassSetSimultaneities methods

UniquePitchClassSetSimultaneities.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

UniqueSetClassSimultaneities¶

class music21.features.native.UniqueSetClassSimultaneities(dataOrStream=None, **keywords)¶

Number of unique set class simultaneities.

>>> s = corpus.parse('bwv66.6')
>>> fe = features.native.UniqueSetClassSimultaneities(s)
>>> fe.extract().vector
[14]

UniqueSetClassSimultaneities bases

FeatureExtractor

UniqueSetClassSimultaneities methods

UniqueSetClassSimultaneities.process()¶: Do processing necessary, storing result in feature.

Methods inherited from FeatureExtractor:

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Table of Contents

Table of Contents

This Page

music21.features.native¶

ChordBassMotionFeature¶

ComposerPopularity¶

DiminishedSeventhSimultaneityPrevalence¶

DiminishedTriadSimultaneityPrevalence¶

DominantSeventhSimultaneityPrevalence¶

FirstBeatAttackPrevalence¶

IncorrectlySpelledTriadPrevalence¶

LandiniCadence¶

LanguageFeature¶

MajorTriadSimultaneityPrevalence¶

MinorTriadSimultaneityPrevalence¶

MostCommonNoteQuarterLength¶

MostCommonNoteQuarterLengthPrevalence¶

MostCommonPitchClassSetSimultaneityPrevalence¶

MostCommonSetClassSimultaneityPrevalence¶

QualityFeature¶

RangeOfNoteQuarterLengths¶

TonalCertainty¶

TriadSimultaneityPrevalence¶

UniqueNoteQuarterLengths¶

UniquePitchClassSetSimultaneities¶

UniqueSetClassSimultaneities¶