Hi David, > Of course you can also do > #(display (let ((res (map ly:pitch-semitones (music-pitches some-music)))) > (map - (cdr res) res))) > > Namely first convert to semitones and then do the difference.
Ah! Perhaps I was on the right path with the first part of what I gave to Mike (which used the ly:pitch-semitones function). > #(display (let ((res (map ly:pitch-semitones (music-pitches some-music)))) > (map - (cdr res) res))) > > #(define-markup-list-command (buzz layout props mus) (ly:music?) > (interpret-markup-list layout props > (map number->string > (let ((res (map ly:pitch-semitones (music-pitches mus)))) > (map - (cdr res) res))))) > > \markup \right-column \with-color #red { \buzz \some-music \vspace #3 } > \markup \right-column \with-color #red { \buzz { c' d' e' c' } } I get errors when I try to compile that: error: syntax error, unexpected MUSIC_IDENTIFIER \markup \right-column \with-color #red { \buzz \some-music \vspace #3 } … Am I missing something? I cut-and-paste your code [from email into Frescobaldi] several times… Thanks, Kieren. ________________________________ Kieren MacMillan, composer (he/him/his) ‣ website: www.kierenmacmillan.info ‣ email: i...@kierenmacmillan.info