The section's letter, assigned in order of first appearance: the opening material is A, the first material unlike it is B, and a later restatement of A is A again. Past Z the letters double (AA, AB), the way spreadsheet columns do. No functional name — verse, chorus, bridge — is ever inferred.
First beat of the section; negative when it opens with a pickup.
End of the section, exclusive.
The section's length in bars.
Index, in the returned array, of the first section carrying this label; the section's own index when it is that first appearance.
How alike this section and its first occurrence are, in [0, 1]; 1 on the first occurrence itself. The mean over the units the section was merged from, each scored against the unit it matched.
How the section came to carry its label.
A span of music labelled by which earlier span it restates.