New in version 2.0.
Change diatonic interval-class segment dic_seg to chord quality string:
abjad> from abjad.tools import tonalitytools
abjad> dic_seg = pitchtools.InversionEquivalentDiatonicIntervalClassSegment([
... pitchtools.InversionEquivalentDiatonicIntervalClass('major', 3),
... pitchtools.InversionEquivalentDiatonicIntervalClass('minor', 3),])
abjad> tonalitytools.diatonic_interval_class_segment_to_chord_quality_string(dic_seg)
'major'
Todo
Implement diatonic_interval_class_set_to_chord_quality_string().