The Note object

Everything you can do with a Note, using as an example gvn:14.1.3.1.1.

Constructor

• Note("gvn:14.1.3.1.1") makes a note from a short URN.
• Note("urn:cite2:zst:gvn:14.1.3.1.1") makes the same note from the full URN.
• Note("gvn:14.1") works too. The missing values default to length 1, no arsis and no hyphen.
• Note("gcn:1") makes the rest. Its sharpening is None.
• An invalid URN raises ValueError. That covers a pitch not in the table, a length outside 1–5, an arsis or hyphen value other than 0 or 1, and badly formed URNs.

Properties of a Note

• n.collection gives 'gvn'.
• n.base gives 14.
• n.sharpening gives 1, meaning no sharp. 2 is the first sharp and 3 the second.
• n.length gives 3. 1 means no length sign; 2 to 5 are diseme, triseme, tetraseme and pentaseme.
• n.arsis gives True.
• n.hyphen gives True.
• n.unicode gives 'Ι', the written symbol. It depends only on the pitch.
• n.name gives "vocal d′".

Identity

• n.urn gives 'gvn:14.1.3.1.1'. It always includes all five values.
• n.full_urn gives 'urn:cite2:zst:gvn:14.1.3.1.1'.
• str(n) gives the same as n.urn.
• repr(n) gives Note('gvn:14.1.3.1.1').

Vocal or instrumental

• n.vocal gives True.
• n.instrumental gives False.

Comparison

• == compares all six values, so Note("gvn:11.1") == Note("gvn:11.1.1.0.0") is True.
• Notes can go in sets and be dictionary keys.
• Notes can’t be changed after creation; assigning to an attribute raises AttributeError.

Working with lists of notes

• parse_notes(s) turns a notation-edition string into a flat list of Note objects.
• parse_note_groups(s) gives one list per syllable, with notes joined by ~ kept together.
• groups_to_unicode(groups) turns those groups back into a Unicode string, with spaces between groups.
• In an alignment, each syllable’s note_group holds its Note objects.

TBD

• The Unicode string shows only the pitch symbol. Length, arsis and hyphen aren’t drawn in it.
• Notes can’t be sorted by pitch.