Re: "Generative music" and "Algorithmic composition"

[Philip Rhoades]

Paul,


On 2014-01-16 07:22, Paul Morris wrote:
> SoundsFromSound wrote
> > Paul, that is a great little bit of code! Thank you for sharing 
> > that...I'm
> > going to play around with it later today. :)
>
> Glad you like it, but David Kastrup gets the credit for it:
> http://lists.gnu.org/archive/html/lilypond-user/2014-01/msg00638.html
>
> I just changed it from a set of 12 chromatic notes to those in C major 
> and
> added \transpose.  Maybe it's worth adding it to the LSR... hmmm... 
> looks
> like there's already a random note generator there:
> http://lsr.dsi.unimi.it/LSR/Item?id=274
>
> It generates notes in the current key from (middle) c' up to g''
> Here it is after running convert-ly (from 2.14.0 to 2.18.0):
>
> \version "2.18.0"
> \score {
>   {
>     $(let ((random-state (seed->random-state (current-time))))
>        (make-sequential-music
>         (map (lambda (x)
>                (let ((idx (random 12 random-state)))
>                  (make-event-chord
>                   (list
>                    (make-music 'NoteEvent
>                      'duration (ly:make-duration 2 0 1/1)
>                      'pitch (ly:make-pitch
>                              (quotient idx 7)
>                              (remainder idx 7)
>                              0))))))
>           (make-list 24))))
>   }
> }


maybe we (and by "we" I mean "you" - at least initially) could enhance 
this little bit of code to do what my Ruby script was doing? - and if 
more people got interested it could develop into something more 
sophisticated with some music theory behind it?  So the first step would 
be a Scheme script that would:

- start with a single random note in a particular key

- most of the time, derive the next note from the current note by 
selecting a note (in the same key) within [+/-]1 of the value of the 
current note

- on some occasions (20% of the time?), selected a note within [+/-]2 of 
the value of the current note

- more rarely (5% of the time?) jump to another completely random note

What do you think?

Regards,

Phil.
--
Philip Rhoades

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