.. _moduleCorpus.base:

music21.corpus.base
===================

.. WARNING: DO NOT EDIT THIS FILE: AUTOMATICALLY GENERATED. Edit the .py file directly

.. module:: music21.corpus.base


The music21 corpus includes a collection of freely distributable
music in MusicXML, Humdrum, and other representations. The corpus
package is an interface for easily working with this data.

To see a complete listing of the works in the music21 corpus,
visit  :ref:`referenceCorpus`.  Note that music21 does not own
most of the music in the corpus -- it has been licensed to us (or
in a free license).  It may not be free in all parts of the world,
but to the best of our knowledge is true for the US.




.. function:: parse(workName, movementNumber=None, number=None, extList=None, forceSource=False)


    The most important method call for corpus.

    Similar to the :meth:`~music21.converter.parse` method of converter (which takes in
    a filepath on the local hard drive), this
    method searches the corpus (including the virtual corpus)
    for a work fitting the workName description and
    returns a :class:`music21.stream.Stream`.

    If `movementNumber` is defined, and a movement is included in the corpus, that movement will be returned.

    If `number` is defined, and the work is a collection with multiple components, that work number will be returned.
    For instance, some of our ABC documents contain dozens of folk songs within a single file.

    Advanced: if `forceSource` is True, the original file will always be loaded freshly and pickled (e.g., pre-parsed) files
    will be ignored.  This should not be needed if the file has been changed, since the filetime of the file and
    the filetime of the pickled version are compared.  But it might be needed if the music21 parsing routine has changed.

    Example, get a chorale by Bach.  Note that the source type does not need to be
    specified, nor does the name Bach even (since it's the only piece with the title BWV 66.6)



    >>> from music21 import *
    >>> bachChorale = corpus.parse('bwv66.6')
    >>> len(bachChorale.parts)
    4

    After parsing, the file path within the corpus is stored as `.corpusFilePath`



    >>> bachChorale.corpusFilepath
    'bach/bwv66.6.mxl'



.. function:: getWork(workName, movementNumber=None, extList=None)

    Search the corpus, then the virtual corpus, for a work, and return a file path or URL. This method will return either a list of file paths or, if there is a single match, a single file path. If no matches are found an Exception is raised.



    >>> from music21 import *
    >>> import os
    >>> a = corpus.getWork('opus74no2', 4)
    >>> a.endswith(os.path.sep.join(['haydn', 'opus74no2', 'movement4.mxl']))
    True
    ⁠ 
    >>> a = corpus.getWork(['haydn', 'opus74no2', 'movement4.xml'])
    >>> a.endswith(os.path.sep.join(['haydn', 'opus74no2', 'movement4.mxl']))
    True




.. function:: addPath(fp)


    Add a directory path to the Local Corpus on a
    *temporary* basis, i.e., just for the current Python
    session. All directories contained within the provided
    directory will be searched for files with file extensions
    matching the currently readable file types. Any number of
    file paths can be added one at a time.

    An error will be raised if the file path does not exist,
    is already defined as a temporary, or is already being
    searched by being defined with the
    :class:`~music21.environment.Environment` 'localCorpusSettings' setting.

    To permanently add a path to the list of stored local corpus paths,
    set the 'localCorpusPath' or 'localCorpusSettings' setting of
    the :class:`~music21.environment.UserSettings` object.



    >>> from music21 import *
    >>> coprus.addPath('~/Documents')

    alternatively, add a directory permanently (see link above
    for more details):



    >>> from music21 import *
    >>> us = environment.UserSettings()
    >>> us['localCorpusPath'] = 'd:/desktop/'

    (then best is to restart music21)




.. function:: cacheMetadata(domainList=['local'])


.. function:: compressAllXMLFiles(deleteOriginal=False)


    Takes all filenames in corpus.paths and runs :meth:`music21.corpus.base.compressXML` on each.
    If the musicXML files are compressed, the originals are deleted from the system.



.. function:: compressXML(filename, deleteOriginal=False)


    Takes a filename, and if the filename corresponds to a musicXML file with an .xml extension,
    creates a corresponding compressed .mxl file in the same directory. If deleteOriginal is set
    to True, the original musicXML file is deleted from the system.



.. function:: getBachChorales(extList='xml')

    Return the file name of all Bach chorales.

    By default, only Bach Chorales in xml format are returned, because the quality of
    the encoding and our parsing of those is superior.



    >>> from music21 import *
    >>> a = corpus.getBachChorales()
    >>> len(a) > 400
    True
    >>> a = corpus.getBachChorales('krn')
    >>> len(a) > 10
    False
    >>> a = corpus.getBachChorales('xml')
    >>> len(a) > 400
    True



.. function:: getBeethovenStringQuartets(extList=None)


    Return a list of all Beethoven String Quartet filenames.



    >>> from music21 import *
    >>> a = corpus.getBeethovenStringQuartets()
    >>> len(a) > 10
    True
    >>> a = corpus.getBeethovenStringQuartets('krn')
    >>> len(a) < 10 and len(a) > 0
    True
    >>> a = corpus.getBeethovenStringQuartets('xml')
    >>> len(a) > 400
    False



.. function:: getComposer(composerName, extList=None)


    Return all filenames in the corpus that match a composer's
    or a collection's name. An `extList`, if provided, defines
    which extensions are returned. An `extList` of None (default) returns
    all extensions.

    Note that xml and mxl are treated equivalently.



    >>> from music21 import *
    >>> a = corpus.getComposer('beethoven')
    >>> len(a) > 10
    True
    >>> a = corpus.getComposer('mozart')
    >>> len(a) > 10
    True
    >>> a = corpus.getComposer('bach', 'krn')
    >>> len(a) < 10
    True
    >>> a = corpus.getComposer('bach', 'xml')
    >>> len(a) > 10
    True



.. function:: getComposerDir(composerName)


    Given the name of a composer, get the path
    to the top-level directory of that composer



    >>> from music21 import *
    >>> import os
    >>> a = corpus.getComposerDir('beethoven')
    >>> a.endswith(os.path.join('corpus', os.sep, 'beethoven'))
    True
    >>> a = corpus.getComposerDir('bach')
    >>> a.endswith(os.path.join('corpus', os.sep, 'bach'))
    True
    >>> a = corpus.getComposerDir('mozart')
    >>> a.endswith(os.path.join('corpus', os.sep, 'mozart'))
    True



.. function:: getCorePaths(extList=None, expandExtensions=True)

    Get all paths in the corpus that match a known extension, or an extenion
    provided by an argument.

    If `expandExtensions` is True, a format for an extension, and related extensions, will replaced by all known input extensions. This is convenient when an input format might match for multiple extensions.



    >>> from music21 import *
    ⁠ 
    >>> a = corpus.getCorePaths()
    >>> len(a) # the current number of paths; update when adding to corpus
    2231



    >>> a = corpus.getCorePaths('krn')
    >>> len(a) >= 4
    True
    ⁠ 
    >>> a = corpus.getCorePaths('abc')
    >>> len(a) >= 10
    True




.. function:: getHandelMessiah(extList='md')


    Return a list of the filenames of all parts of Handel's Messiah.



    >>> from music21 import *
    >>> a = corpus.getHandelMessiah()
    >>> len(a)
    43



.. function:: getLocalPaths(extList=None, expandExtensions=True)


    Access files in additional directories supplied by the user and defined in environment settings. If additional paths are added on a per-session basis witht the :func:`~music21.corpus.addPath` function, these paths are also retuned with this method.



.. function:: getMonteverdiMadrigals(extList='xml')


    Return a list of the filenames of all Monteverdi madrigals.



    >>> from music21 import *
    >>> a = corpus.getMonteverdiMadrigals()
    >>> len(a) > 40
    True



.. function:: getPaths(extList=None, expandExtensions=True, domain=['core', 'virtual', 'local'])


    Get paths from core, virtual, and/or local domains.
    This is the public interface for getting all corpus
    paths with one function.



.. function:: getVirtualPaths(extList=None, expandExtensions=True)

    Get all paths in the virtual corpus that match a known extension. An extension of None will return all known extensions.



    >>> from music21 import *
    >>> len(corpus.getVirtualPaths()) > 6
    True



.. function:: getVirtualWorkList(workName, movementNumber=None, extList=None)

    Given a work name, search all virtual works and return a list of URLs for any matches.



    >>> from music21 import *
    >>> corpus.getVirtualWorkList('bach/bwv1007/prelude')
    ['http://kern.ccarh.org/cgi-bin/ksdata?l=cc/bach/cello&file=bwv1007-01.krn&f=xml']
    ⁠ 
    >>> corpus.getVirtualWorkList('junk')
    []



.. function:: getWorkList(workName, movementNumber=None, extList=None)


    Search the corpus and return a list of filenames of works,
    always in a list.

    If no matches are found, an empty list is returned.



    >>> from music21 import *
    >>> len(corpus.getWorkList('beethoven/opus18no1'))
    8
    >>> len(corpus.getWorkList('beethoven/opus18no1', 1))
    2
    >>> len(corpus.getWorkList('beethoven/opus18no1', 1, '.krn'))
    1
    >>> len(corpus.getWorkList('beethoven/opus18no1', 1, '.xml'))
    1
    >>> len(corpus.getWorkList('beethoven/opus18no1', 0, '.xml'))
    0
    >>> len(corpus.getWorkList('handel/hwv56', '1-02', '.md'))
    1
    >>> len(corpus.getWorkList('handel/hwv56', (2,1), '.md'))
    1
    ⁠ 
    >>> len(corpus.getWorkList('bach/artOfFugue_bwv1080', 2, '.md'))
    1




.. function:: getWorkReferences(sort=True)

    Return a data dictionary for all works in the corpus and (optionally) the virtual corpus. Returns a list of reference dictionaries, each each dictionary for a each composer. A 'works' dictionary for each composer provides references to dictionaries for all associated works.

    This is used in the generation of corpus documentation



    >>> from music21 import *
    >>> post = corpus.getWorkReferences()



.. function:: parseWork(*arguments, **keywords)

    This function exists for backwards compatibility. All calls should use :func:`~music21.corpus.parse` instead.



.. function:: search(query, field=None, domain=['core', 'virtual', 'local'], extList=None)

    Search all stored metadata and return a list of file paths; to
    return a list of parsed Streams, use searchParse().

    The `domain` parameter can be used to specify one of three corpora:
    core (included with music21), virtual (defined in music21 but hosted
    online), and local (hosted on the user's system (not yet implemented)).

    This method uses stored metadata and thus, on first usage, will
    incur a performance penalty during metadata loading.



