Shuffling and fading harmonics

In this example, we will use some of auxjad’s classes to manipulate some musical material using the auxjad.Shuffler and auxjad.Fader classes.

First, we start by importing both abjad and auxjad.

>>> import abjad
>>> import auxjad

Let’s now create a container with some arbitrary material to be manipulated. Let’s use the class auxjad.ArtificialHarmonic as well as some chords and rests.

>>> container = abjad.Container([
...     auxjad.ArtificialHarmonic(r"<ef' af'>4"),
...     auxjad.ArtificialHarmonic(r"<b e'>8."),
...     auxjad.ArtificialHarmonic(r"<g c'>16", is_parenthesized=True),
...     abjad.Rest(r"r4"),
...     abjad.Chord([-5, 8, 9], (1, 8)),
...     auxjad.ArtificialHarmonic(r"<d' a'>8", is_parenthesized=True),
... ])
>>> abjad.show(container)

The spelling of the chord <g af' a'> could be improved. This can be done by using auxjad.mutate.respell_augmented_unisons(). Auxjad automatically adds this mutation as an extension method to abjad.mutate so it can also be accessed using abjad.mutate.respell_augmented_unisons().

>>> abjad.mutate.respell_augmented_unisons(container[:])
>>> abjad.show(container)

Let’s now use this material as input for auxjad.Shuffler. This class will randomly shuffle the logical ties of the input container.

>>> shuffler = auxjad.Shuffler(container,
...                            disable_rewrite_meter=True,
...                            )

We can now use the method shuffle_n() to generate some measures of shuffled logical ties.

>>> staff = abjad.Staff()
>>> notes = shuffler.shuffle_n(4)
>>> staff.append(notes)
>>> abjad.show(staff)

We can now grab the last window output by shuffler and use it as the input container of a auxjad.Fader. When its property mode is set to 'out', it will remove a logical tie one by one at each iteration. Note how auxjad.Fader removes the notes of chords one by one, but consider an auxjad.ArtificialHarmonic as a single note.

>>> container = abjad.Container(shuffler.current_window)
>>> fader = auxjad.Fader(container, mode='out')
>>> notes = fader.output_all()
>>> staff.append(notes)
>>> abjad.show(staff)

Notice that the time signature has been repeated. While the method output_all() takes care of repeated time signatures, dynamics, and clefs, consecutive calls may result in repetitions. But we can simply use auxjad.mutate.remove_repeated_time_signatures() to take care of that for us. This function is also available as the extension method abjad.mutate.remove_repeated_time_signatures(), which Auxjad automatically adds to abjad.mutate. To finalise the score, let’s remove the last empty measure and add a final bar line.

>>> abjad.mutate.remove_repeated_time_signatures(staff[:])
>>> staff.pop(-1)
>>> score = abjad.Score([staff])
>>> score.add_final_bar_line()
>>> abjad.show(score)