Track Class

The muspy.Track class is a container for music tracks. In MusPy, each track contains only one instrument.

Attributes	Description	Type	Default
program	MIDI program number	int (0-127)	0
is_drum	If it is a drum track	bool	False
name	Track name	str
notes	Musical notes	list of `muspy.Note`	[]
chords	Chords	list of `muspy.Chord`	[]
lyrics	Lyrics	list of `muspy.Lyric`	[]
annotations	Annotations	list of `muspy.Annotation`	[]

(MIDI program number is based on General MIDI specification; see here.)

class muspy.Track(program=0, is_drum=False, name=None, notes=None, chords=None, lyrics=None, annotations=None)[source]

A container for music track.

program

Program number, according to General MIDI specification [1]. Valid values are 0 to 127.

Type:: int, default: 0 (Acoustic Grand Piano)

is_drum

Whether it is a percussion track.

Type:: bool, default: False

name

Track name.

Type:: str, optional

notes

Musical notes.

Type:: list of muspy.Note, default: []

chords

Chords.

Type:: list of muspy.Chord, default: []

annotations

Annotations.

Type:: list of muspy.Annotation, default: []

lyrics

Lyrics.

Type:: list of muspy.Lyric, default: []

Note

Indexing a Track object returns the note at a certain index. That is, track[idx] returns track.notes[idx]. Length of a Track object is the number of notes. That is, len(track) returns len(track.notes).

References

adjust_time(func, attr=None, recursive=True)

Adjust the timing of time-stamped objects.

Parameters:

func (callable) – The function used to compute the new timing from the old timing, i.e., new_time = func(old_time).
attr (str, optional) – Attribute to adjust. Defaults to adjust all attributes.
recursive (bool, default: True) – Whether to apply recursively.

Return type:

Object itself.

append(obj)

Append an object to the corresponding list.

This will automatically determine the list attributes to append based on the type of the object.

Parameters:: obj – Object to append.

copy()

Return a shallow copy of the object.

This is equivalent to copy.copy(self)().

Return type:: Shallow copy of the object.

deepcopy()

Return a deep copy of the object.

This is equivalent to copy.deepcopy(self)()

Return type:: Deep copy of the object.

extend(other, deepcopy=False)

Extend the list(s) with another object or iterable.

Parameters:

other (muspy.ComplexBase or iterable) – If an object of the same type is given, extend the list attributes with the corresponding list attributes of the other object. If an iterable is given, call muspy.ComplexBase.append() for each item.
deepcopy (bool, default: False) – Whether to make deep copies of the appended objects.

Return type:

Object itself.

fix_type(attr=None, recursive=True)

Fix the types of attributes.

Parameters:

attr (str, optional) – Attribute to adjust. Defaults to adjust all attributes.
recursive (bool, default: True) – Whether to apply recursively.

Return type:

Object itself.

classmethod from_dict(dict_, strict=False, cast=False)

Return an instance constructed from a dictionary.

Instantiate an object whose attributes and the corresponding values are given as a dictionary.

Parameters:

dict (dict or mapping) – A dictionary that stores the attributes and their values as key-value pairs, e.g., {“attr1”: value1, “attr2”: value2}.
strict (bool, default: False) – Whether to raise errors for invalid input types.
cast (bool, default: False) – Whether to cast types.

Return type:

Constructed object.

is_valid(attr=None, recursive=True)

Return True if an attribute has a valid type and value.

This will recursively apply to an attribute’s attributes.

Parameters:

attr (str, optional) – Attribute to validate. Defaults to validate all attributes.
recursive (bool, default: True) – Whether to apply recursively.

Returns:

Whether the attribute has a valid type and value.

Return type:

bool

See also

muspy.Base.validate(): Raise an error if an attribute has an invalid type or value.
muspy.Base.is_valid_type(): Return True if an attribute is of a valid type.

is_valid_type(attr=None, recursive=True)

Return True if an attribute is of a valid type.

This will apply recursively to an attribute’s attributes.

Parameters:

attr (str, optional) – Attribute to validate. Defaults to validate all attributes.
recursive (bool, default: True) – Whether to apply recursively.

Returns:

Whether the attribute is of a valid type.

Return type:

bool

See also

muspy.Base.validate_type(): Raise an error if a certain attribute is of an invalid type.
muspy.Base.is_valid(): Return True if an attribute has a valid type and value.

pretty_str(skip_missing=True)

Return the attributes as a string in a YAML-like format.

Parameters:: skip_missing (bool, default: True) – Whether to skip attributes with value None or those that are empty lists.
Returns:: Stored data as a string in a YAML-like format.
Return type:: str

See also

muspy.Base.print(): Print the attributes in a YAML-like format.

print(skip_missing=True)

Print the attributes in a YAML-like format.

Parameters:: skip_missing (bool, default: True) – Whether to skip attributes with value None or those that are empty lists.

See also

muspy.Base.pretty_str(): Return the the attributes as a string in a YAML-like format.

remove_duplicate(attr=None, recursive=True)

Remove duplicate items from a list attribute.

Parameters:

attr (str, optional) – Attribute to check. Defaults to check all attributes.
recursive (bool, default: True) – Whether to apply recursively.

Return type:

Object itself.

remove_invalid(attr=None, recursive=True)

Remove invalid items from a list attribute.

Parameters:

attr (str, optional) – Attribute to validate. Defaults to validate all attributes.
recursive (bool, default: True) – Whether to apply recursively.

Return type:

Object itself.

sort(attr=None, recursive=True)

Sort a list attribute.

Parameters:

attr (str, optional) – Attribute to sort. Defaults to sort all attributes.
recursive (bool, default: True) – Whether to apply recursively.

Return type:

Object itself.

to_ordered_dict(skip_missing=True, deepcopy=True)

Return the object as an OrderedDict.

Return an ordered dictionary that stores the attributes and their values as key-value pairs.

Parameters:

skip_missing (bool, default: True) – Whether to skip attributes with value None or those that are empty lists.
deepcopy (bool, default: True) – Whether to make deep copies of the attributes.

Returns:

A dictionary that stores the attributes and their values as key-value pairs, e.g., {“attr1”: value1, “attr2”: value2}.

Return type:

OrderedDict

validate(attr=None, recursive=True)

Raise an error if an attribute has an invalid type or value.

This will apply recursively to an attribute’s attributes.

Parameters:

attr (str, optional) – Attribute to validate. Defaults to validate all attributes.
recursive (bool, default: True) – Whether to apply recursively.

Return type:

Object itself.

See also

muspy.Base.is_valid(): Return True if an attribute has a valid type and value.
muspy.Base.validate_type(): Raise an error if an attribute is of an invalid type.

validate_type(attr=None, recursive=True)

Raise an error if an attribute is of an invalid type.

This will apply recursively to an attribute’s attributes.

Parameters:

attr (str, optional) – Attribute to validate. Defaults to validate all attributes.
recursive (bool, default: True) – Whether to apply recursively.

Return type:

Object itself.

See also

muspy.Base.is_valid_type(): Return True if an attribute is of a valid type.
muspy.Base.validate(): Raise an error if an attribute has an invalid type or value.

get_end_time(is_sorted=False)[source]

Return the time of the last event.

This includes notes, chords, lyrics and annotations.

Parameters:: is_sorted (bool, default: False) – Whether all the list attributes are sorted.

clip(lower=0, upper=127)[source]

Clip the velocity of each note.

Parameters:

lower (int, default: 0) – Lower bound.
upper (int, default: 127) – Upper bound.

Return type:

Object itself.

transpose(semitone)[source]

Transpose the notes by a number of semitones.

Parameters:: semitone (int) – Number of semitones to transpose the notes. A positive value raises the pitches, while a negative value lowers the pitches.
Return type:: Object itself.

trim(end)[source]

Trim the track.

Parameters:: end (int) – End time, excluding (i.e, the max time will be end - 1).
Return type:: Object itself.