DCML>RNTXT conversion (bug). Metric distortions due to empty labels #82
Description
Hi @MarkGotham and @malcolmsailor,
The m21 stream of Tchaikovsky op37a08 has a metric bump in m. 5 whose offset comes an eighth early:
{0.0} <music21.metadata.Metadata object at 0x7f402fad6d40>
{0.0} <music21.stream.Part 0x7f40dccc9d20>
{0.0} <music21.stream.Measure 0 offset=0.0>
{0.0} <music21.key.Key of b minor>
{0.0} <music21.meter.TimeSignature 6/8>
{0.0} <music21.roman.RomanNumeral i6 in b minor>
{1.0} <music21.stream.Measure 1 offset=1.0>
{0.0} <music21.roman.RomanNumeral i in b minor>
{1.0} <music21.roman.RomanNumeral #viio6 in b minor>
{2.0} <music21.roman.RomanNumeral VI6 in b minor>
{4.0} <music21.stream.Measure 2 offset=4.0>
{0.0} <music21.roman.RomanNumeral VI6 in b minor>
{1.0} <music21.roman.RomanNumeral V6 in b minor>
{2.0} <music21.roman.RomanNumeral vo6 in b minor>
{7.0} <music21.stream.Measure 3 offset=7.0>
{0.0} <music21.roman.RomanNumeral vo6 in b minor>
{1.0} <music21.roman.RomanNumeral IV6 in b minor>
{2.0} <music21.roman.RomanNumeral #viio2 in b minor>
{10.0} <music21.stream.Measure 4 offset=10.0>
{0.0} <music21.roman.RomanNumeral V[no5][add6] in b minor>
{1.0} <music21.roman.RomanNumeral #viio64 in b minor>
{1.5} <music21.roman.RomanNumeral i in b minor>
{12.5} <music21.stream.Measure 5 offset=12.5>
{0.0} <music21.roman.RomanNumeral VI in b minor>
{1.0} <music21.roman.RomanNumeral iv65 in b minor>
{1.5} <music21.roman.RomanNumeral Ger6 in b minor>
Inspecting the rntext reveals an empty label at the end of m. 4:
The problem is caused by non-harmony labels such as { and seems to be happening systematically, e.g.:
The problem can easily be avoided by skipping all rows that have an empty value in the column chord while converting, e.g.