Children, Regions, and Timestamps

Hierarchy, cross-section queries

Children, Regions, and Timestamps

Timelines nest inside one another. A timestamp is a cross-section that shows where you are in every active child at a given root coordinate.

from pathlib import Path

from timetoalign.loader.score.partitura import PartituraLoader

Load a Structured Score

DATA_DIR = Path(".").resolve().parents[1] / "tests" / "data" / "vienna_1x22"

loader = PartituraLoader()
loader.load(DATA_DIR / "Chopin_op10_no3.musicxml")
tl = loader.create_timeline(uid="chopin_etude")
tl

ContinuousLogicalTimeline[chopin_etude] (547 events, 4 children, 3 cmaps)
                      0 ________________________________ 41.5 quarters
  ├─ notes            0 ________________________________ 41.5 (498 events)
  ├─ measures         0 ________________________________ 41.5 (22 events)
  ├─ controls         0 ______________________________   40 (22 events)
  └─ annotations      0 _________________________        32.5 (5 events)

Measures as Regions

The loader’s EventStore contains measure intervals. We can filter notes by coordinate bounds.

measures = loader.store.measures.to_dataframe()
m2 = measures.iloc[1]
{
    "measure": 2,
    "start": float(m2.start),
    "end": float(m2.end),
}

{'measure': 2, 'start': 0.5, 'end': 2.5}

tl.get_child("notes").get_events(
    event_type="Note", min_coord=float(m2.start), max_coord=float(m2.end)
).to_dataframe().head()

	id	name	temporal_type	event_type	start	end	duration	duration_float	mc	mn	...	specific_pitch	tpc	octave	velocity	gracenote	chord_id	voice	staff	part_id
0	notes:note:000002	E4	interval	Note	1/2	1.00	1/2	0.50	2	2	...	{'gpc_int': 2, 'gpc_str': 'E', 'acc': 0, 'spc_...	4	4	64	NaN	NaN	1	1	P1
1	notes:note:000003	G♯3	interval	Note	1/2	0.75	1/4	0.25	2	2	...	{'gpc_int': 4, 'gpc_str': 'G', 'acc': 1, 'spc_...	8	3	64	NaN	NaN	3	1	P1
2	notes:note:000004	E2	interval	Note	1/2	0.75	1/4	0.25	2	2	...	{'gpc_int': 2, 'gpc_str': 'E', 'acc': 0, 'spc_...	4	2	64	NaN	NaN	4	2	P1
3	notes:note:000005	E2	interval	Note	1/2	1.50	1	1.00	2	2	...	{'gpc_int': 2, 'gpc_str': 'E', 'acc': 0, 'spc_...	4	2	64	NaN	NaN	7	2	P1
4	notes:note:000006	B3	interval	Note	3/4	1.00	1/4	0.25	2	2	...	{'gpc_int': 6, 'gpc_str': 'B', 'acc': 0, 'spc_...	5	3	64	NaN	NaN	3	1	P1

5 rows × 23 columns

Timestamps: Cross-Section Queries

At root coordinate X, what is the local coordinate inside each active child timeline?

timestamps_df = tl.get_timestamps()
timestamps_df.head(10)

	axis (quarters)	chopin_etude (quarters)	notes (quarters)	measures (quarters)	controls (quarters)	annotations (quarters)	quarters_to_ticks (ticks)	quarters_to_measures (measures)	raw_quarters (quarters)
id
notes:note:000001	0	0	0	0	0	0	0	1	-1/2
notes:note:000002	1/2	1/2	1/2	1/2	1/2	1/2	240	2	0
notes:note:000006	3/4	3/4	3/4	3/4	3/4	3/4	360	17/8	1/4
notes:note:000008	1	1	1	1	1	1	480	9/4	1/2
notes:note:000010	5/4	5/4	5/4	5/4	5/4	5/4	600	19/8	3/4
notes:note:000013	3/2	3/2	3/2	3/2	3/2	3/2	720	5/2	1
notes:note:000018	7/4	7/4	7/4	7/4	7/4	7/4	840	21/8	5/4
notes:note:000020	2	2	2	2	2	2	960	11/4	3/2
notes:note:000021	9/4	9/4	9/4	9/4	9/4	9/4	1080	23/8	7/4
notes:note:000023	5/2	5/2	5/2	5/2	5/2	5/2	1200	3	2

NaN means the coordinate falls outside that child’s extent.

Next: Timeline Groups