The relative module

Utilities and functions to manipulate music written in relative pitches.

class Rel2abs(processor=None, first_pitch_absolute=None)

Bases: Edit

Convert \relative music to absolute.

Removes the \relative command and makes all pitches absolute.

processor: a PitchProcessor; a default one is used if none is specified.

first_pitch_absolute: if True, the first pitch in a \relative expression is considered to be absolute, when a startpitch is not given. This is LilyPond >= 2.18 behaviour. If False, the first pitch in a \relative expression is considered to be relative to c’, if no startpitch is given. This is LilyPond < 2.18 behaviour. If not specified, the function looks at the LilyPond version from the document. If the version can’t be determined, defaults to False, the old behaviour.

You may change these attributes after instantiation.

processor

The PitchProcessor; a default one is used if None is specified.

first_pitch_absolute

Whether to consider the first pitch in a \relative expression absolute if a start pitch is not used (by default dependent on LilyPond version).

edit_range(r)

Do the pitch conversion.

rel2abs(music)

Convenience function to convert relative music to absolute in music.

The music may be a parce document or cursor, a node range or an element node.

class Abs2rel(processor=None, start_pitch=True, first_pitch_absolute=None)

Bases: Edit

Convert music in absolute notation to \relative notation.

The topmost MusicList ({ … } or << … >>) that has child notes gets a Relative parent node.

processor: a PitchProcessor; a default one is used if none is specified.

start_pitch: if True, a starting pitch is written after the \relative command.

start_pitch: if False, the first_pitch_absolute attribute determines the meaning of the first pitch in the new Relative expression. If first_pitch_absolute is True, the first pitch in the \relative expression is considered to be absolute, when a startpitch is not given. This is LilyPond >= 2.18 behaviour. If False, the first pitch in a \relative expression is considered to be relative to c’, if no start pitch is given. This is LilyPond < 2.18 behaviour. If not specified, the function looks at the LilyPond version from the document. If the version can’t be determined, defaults to False, the old behaviour.

You may change these attributes after instantiation.

processor

The PitchProcessor; a default one is used if None is specified.

start_pitch

Whether to write a starting pitch after the \relative command.

first_pitch_absolute

Whether to consider the first pitch in a \relative expression absolute if a start pitch is not used (by default dependent on LilyPond version).

edit_range(r)

Do the pitch conversion.

make_relative(node)

Make al notes and pitched rests in the specified MusicList or SimultaneousMusicList node relative.

Returns a Relative node with the modified music list appended.

Replace the node in its parent with the returned node if desired.

abs2rel(music)

Convenience function to convert absolute music to relative.

The music may be a parce document or cursor, a node range or an element node.