Re: detecting parallel fifths and octaves in figured bass

[David Nalesnik]

Hi all,

On Fri, Jul 14, 2023 at 6:36 PM Jean Abou Samra <jean@abou-samra.fr> wrote:

Le vendredi 14 juillet 2023 à 21:08 +0000, Eef Weenink a écrit :

Maybe somebody already made a script for this:

In figured bass there are two fundamental rules: Avoid parallell octaves and or fifhts.

So it would be nice to have some scipts what checks for this. So if two voices have a distance of a fifth or octave, the next chord is checked if the same two voices have a fifth or octave too. If so, they are parallel.

Something like that was posted on the list years ago, though I don't have the time right now to test it on newer versions.

https://lists.gnu.org/archive/html/lilypond-user/2017-09/msg00449.html

Best,

Jean

This is a proof-of-concept which in the passing years has been expanded to create partwriter.com.  It is no longer written in LilyPond/Scheme - rather in JS.  It will output a LilyPond file of the results, and can be used with https://github.com/davidnalesnik/lilypond-roman-numeral-tool for Roman numeral markup in the LilyPond file.  It isn't framed as a part writing checker, instead it will output varied solutions without those errors to begin with.

Best,

David