music21.metadata.primitives

Text

class music21.metadata.primitives.Text(data='', language=None)

One unit of text data: a title, a name, or some other text data. Store the string and a language name or code. This object can be used and/or subclassed for a variety for of text storage.

>>> td = metadata.Text('concerto in d', 'en')
>>> str(td)
'concerto in d'
>>> td.language
'en'

Text bases

Text read-only properties

Read-only properties inherited from ProtoM21Object:

Text read/write properties

Text.language

Set the language of the Text stored within.

>>> t = metadata.Text('my text')
>>> t.language = 'en'
>>> t.language
'en'

Text methods

Text.getNormalizedArticle()

Return a string representation with normalized articles.

>>> td = metadata.Text('Ale is Dear, The', language='en')
>>> str(td)
'Ale is Dear, The'

>>> td.getNormalizedArticle()
'The Ale is Dear'

The language will determine whether the article is moved:

>>> td.language = 'de'
>>> td.getNormalizedArticle()
'Ale is Dear, The'

Methods inherited from ProtoM21Object:

Date

class music21.metadata.primitives.Date(*args, **keywords)

A single date value, specified by year, month, day, hour, minute, and second. Note that this class has been created, instead of using Python’s datetime, to provide greater flexibility for processing unconventional dates, ancient dates, dates with error, and date ranges.

The datetime property can be used to retrieve a datetime object when necessary.

Additionally, each value can be specified as uncertain or approximate; if None, assumed to be certain.

Data objects are fundamental components of DateSingle and related subclasses that represent single dates and date ranges.

>>> a = metadata.Date(year=1843, yearError='approximate')
>>> a.year
1843

>>> a.yearError
'approximate'

>>> a = metadata.Date(year='1843?')
>>> a.yearError
'uncertain'

Date bases

Date read-only properties

Date.datetime

Get a datetime object from a metadata.Date() object

>>> a = metadata.Date(year=1843, month=3, day=3)
>>> str(a)
'1843/03/03'

>>> a.datetime
datetime.datetime(1843, 3, 3, 0, 0)

Lack of a required date element raises an exception:

>>> a = metadata.Date(year=1843, month=3)
>>> str(a)
'1843/03/--'

>>> a.datetime
Traceback (most recent call last):
TypeError: ...argument 'day' (pos 3)...
Date.hasError

Return True if any data points have error defined:

>>> a = metadata.Date(
...     year=1843,
...     month=3,
...     day=3,
...     dayError='approximate',
...     )
>>> a.hasError
True

>>> b = metadata.Date(
...     year=1843,
...     month=3,
...     day=3,
...     minute=3,
...     )
>>> b.hasError
False
Date.hasTime

Return True if any time elements are defined:

>>> a = metadata.Date(year=1843, month=3, day=3)
>>> a.hasTime
False

>>> b = metadata.Date(year=1843, month=3, day=3, minute=3)
>>> b.hasTime
True

Read-only properties inherited from ProtoM21Object:

Date methods

static Date.errorToSymbol(value)

Convert an error string (approximate, uncertain) into a symbol.

>>> metadata.Date.errorToSymbol('approximate')
'~'

>>> metadata.Date.errorToSymbol('uncertain')
'?'
Date.load(value)

Load values by string, datetime object, or Date object:

>>> a = metadata.Date(year=1843, month=3, day=3)
>>> b = metadata.Date()
>>> b.load(a)
>>> b.year
1843
Date.loadDatetime(dt)

Load time data from a datetime object:

>>> import datetime
>>> dt = datetime.datetime(2005, 2, 1)
>>> dt
datetime.datetime(2005, 2, 1, 0, 0)

>>> m21mdDate = metadata.Date()
>>> m21mdDate.loadDatetime(dt)
>>> str(m21mdDate)
'2005/02/01'
Date.loadOther(other)

Load values based on another Date object:

>>> a = metadata.Date(year=1843, month=3, day=3)
>>> b = metadata.Date()
>>> b.loadOther(a)
>>> b.year
1843
Date.loadStr(dateStr)

Load a string date representation.

Assume year/month/day/hour:minute:second:

>>> d = metadata.Date()
>>> d.loadStr('1030?/12~/?4')
>>> d.month, d.monthError
(12, 'approximate')

>>> d.year, d.yearError
(1030, 'uncertain')

>>> d.month, d.monthError
(12, 'approximate')

>>> d.day, d.dayError
(4, 'uncertain')

>>> d = metadata.Date()
>>> d.loadStr('1834/12/4/4:50:32')
>>> d.minute, d.second
(50, 32)

Methods inherited from ProtoM21Object:

DateSingle

class music21.metadata.primitives.DateSingle(data: Any = '', relevance='certain')

Store a date, either as certain, approximate, or uncertain relevance.

The relevance attribute is limited within each DateSingle subclass depending on the design of the class. Alternative relevance types should be configured as other DateSingle subclasses.

>>> dd = metadata.DateSingle('2009/12/31', 'approximate')
>>> dd
<music21.metadata.primitives.DateSingle 2009/12/31>

>>> str(dd)
'2009/12/31'

>>> dd.relevance
'approximate'

>>> dd = metadata.DateSingle('1805/3/12', 'uncertain')
>>> str(dd)
'1805/03/12'

DateSingle bases

DateSingle read-only properties

DateSingle.datetime

Get a datetime object.

>>> a = metadata.DateSingle('1843/03/03')
>>> str(a)
'1843/03/03'

>>> a.datetime
datetime.datetime(1843, 3, 3, 0, 0)

>>> a = metadata.DateSingle('1843/03')
>>> str(a)
'1843/03/--'

Read-only properties inherited from ProtoM21Object:

DateSingle read/write properties

DateSingle.relevance

The relevance attribute takes one of three values, ‘certain’, ‘approximate’, or ‘uncertain’.

DateSingle methods

Methods inherited from ProtoM21Object:

DateRelative

class music21.metadata.primitives.DateRelative(data='', relevance='after')

Store a relative date, sometime prior or sometime after, onorbefore, or onorafter`.

>>> dd = metadata.DateRelative('2009/12/31', 'prior')
>>> str(dd)
'prior to 2009/12/31'
>>> dd.relevance = 'after'
>>> str(dd)
'after 2009/12/31'

>>> dd = metadata.DateRelative('2009/12/31', 'certain')
Traceback (most recent call last):
music21.exceptions21.MetadataException: Relevance value is not
    supported by this object: 'certain'

DateRelative bases

DateRelative read-only properties

Read-only properties inherited from DateSingle:

Read-only properties inherited from ProtoM21Object:

DateRelative read/write properties

DateRelative.relevance

The relevance attribute takes one of four values, ‘prior’, ‘after’, or ‘onorbefore’ or ‘onorafter’.

DateRelative methods

Methods inherited from ProtoM21Object:

DateBetween

class music21.metadata.primitives.DateBetween(data: Optional[Iterable[str]] = None, relevance='between')

Store a relative date, sometime between two dates:

>>> dd = metadata.DateBetween(['2009/12/31', '2010/1/28'])
>>> str(dd)
'2009/12/31 to 2010/01/28'

>>> dd = metadata.DateBetween(['2009/12/31', '2010/1/28'], 'certain')
Traceback (most recent call last):
music21.exceptions21.MetadataException: Relevance value is not
    supported by this object: 'certain'

DateBetween bases

DateBetween read-only properties

Read-only properties inherited from DateSingle:

Read-only properties inherited from ProtoM21Object:

DateBetween read/write properties

DateBetween.relevance

The relevance attribute takes only one value: ‘between’.

DateBetween methods

Methods inherited from ProtoM21Object:

DateSelection

class music21.metadata.primitives.DateSelection(data: Optional[Iterable[str]] = None, relevance='or')

Store a selection of dates, or a collection of dates that might all be possible

>>> dd = metadata.DateSelection(
...     ['2009/12/31', '2010/1/28', '1894/1/28'],
...     'or',
...     )
>>> str(dd)
'2009/12/31 or 2010/01/28 or 1894/01/28'

>>> dd = metadata.DateSelection(
...     ['2009/12/31', '2010/1/28'],
...     'certain',
...     )
Traceback (most recent call last):
music21.exceptions21.MetadataException: Relevance value is not
    supported by this object: 'certain'

DateSelection bases

DateSelection read-only properties

Read-only properties inherited from DateSingle:

Read-only properties inherited from ProtoM21Object:

DateSelection read/write properties

DateSelection.relevance

The relevance attribute takes only one value: ‘or’.

DateSelection methods

Methods inherited from ProtoM21Object:

Contributor

class music21.metadata.primitives.Contributor(*args, **keywords)

A person that contributed to a work. Can be a composer, lyricist, arranger, or other type of contributor. In MusicXML, these are “creator” elements.

>>> td = metadata.Contributor(role='composer', name='Chopin, Fryderyk')
>>> td.role
'composer'

>>> td.name
'Chopin, Fryderyk'

>>> td.relevance
'contributor'

>>> td
<music21.metadata.primitives.Contributor composer:Chopin, Fryderyk>

Contributor bases

Contributor read-only properties

Read-only properties inherited from ProtoM21Object:

Contributor read/write properties

Contributor.name

Returns the text name, or the first of many names entered.

>>> td = metadata.Contributor(
...     role='composer',
...     names=['Chopin, Fryderyk', 'Chopin, Frederick'],
...     )
>>> td.name
'Chopin, Fryderyk'

>>> td.names
['Chopin, Fryderyk', 'Chopin, Frederick']
Contributor.names

Returns all names in a list.

>>> td = metadata.Contributor(
...     role='composer',
...     names=['Chopin, Fryderyk', 'Chopin, Frederick'],
...     )
>>> td.names
['Chopin, Fryderyk', 'Chopin, Frederick']

>>> td.names = ['Czerny', 'Spohr']
>>> td.names
['Czerny', 'Spohr']
Contributor.role

The role is what part this Contributor plays in the work. Both full roll strings and roll abbreviations may be used.

>>> td = metadata.Contributor()
>>> td.role = 'composer'
>>> td.role
'composer'

In case of a Humdrum role abbreviation, the role that is set is the full name:

>>> td.role = 'lor'
>>> td.role
'orchestrator'

Roles can be created on the fly:

>>> td.role = 'court jester'
>>> td.role
'court jester'

Contributor methods

static Contributor.abbreviationToRole(abbreviation)

Convert abbreviation to role name:

>>> metadata.Contributor.abbreviationToRole('com')
'composer'

>>> metadata.Contributor.abbreviationToRole('lib')
'librettist'
Contributor.age() → Optional[music21.metadata.primitives.DateSingle]

Calculate the age at death of the Contributor, returning a datetime.timedelta object.

>>> a = metadata.Contributor(
...     name='Beethoven, Ludwig van',
...     role='composer',
...     birth='1770/12/17',
...     death='1827/3/26',
...     )

>>> a.birth
<music21.metadata.primitives.DateSingle 1770/12/17>

>>> a.age()  # the format of timedelta representation changed in 3.7
datetime.timedelta(...20552)

>>> a.age().days
20552

>>> years = a.age().days // 365
>>> years
56

If the composer is still alive, it returns the composer’s current age.

>>> shaw = metadata.Contributor(
...     name='Shaw, Caroline',
...     role='composer',
...     birth='1982/08/01',
...     )
>>> shaw_years = shaw.age().days // 365

This test will fail in 2067:

>>> 36 < shaw_years < 85
True
static Contributor.roleToAbbreviation(roleName)

Convert roleName to role abbreviation:

>>> metadata.Contributor.roleToAbbreviation('composer')
'com'

Methods inherited from ProtoM21Object:

Creator

class music21.metadata.primitives.Creator(*args, **keywords)

A person that created a work. Can be a composer, lyricist, arranger, or other type of contributor.

In MusicXML, these are “creator” elements.

>>> td = metadata.Creator(role='composer', name='Chopin, Fryderyk')
>>> td.role
'composer'

>>> td.name
'Chopin, Fryderyk'

>>> td.relevance
'creator'

Creator bases

Creator read-only properties

Read-only properties inherited from ProtoM21Object:

Creator read/write properties

Read/write properties inherited from Contributor:

Creator methods

Methods inherited from Contributor:

Methods inherited from ProtoM21Object:

Imprint

class music21.metadata.primitives.Imprint(*args, **keywords)

An object representation of imprint, or publication.

Imprint bases

Imprint read-only properties

Read-only properties inherited from ProtoM21Object:

Imprint methods

Methods inherited from ProtoM21Object: