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terekita

gen-repeat w. omn lists

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Hello, newbie question:

 

I'd like to take an omn list and simply repeat each measure 3 times. If I start with the following code:

(setf r-transitions1
      '((e (e 1)(-e 3))
        (-e (e 3)(-e 1))))

(setf marked
      (gen-markov-from-transitions r-transitions1 :size 120))

;;conform to timesignature in omn format
(setf r1 (length-span (gen-repeat 20 '8/8) marked :omn t))

;;define the time signatures
(setf timesigs (get-time-signature r1))

;;stream of pitches
(setf pitches '(c4 eb4 f4 g4 bb4 c5 eb5))

(setf pitches (chord-interval-add '(12) pitches))

;;by spanning r1 onto pitches, pitches will repeat as needed
(setf pitches (span r1 pitches))

(setf rh (make-omn 
           :length r1
           :pitch pitches))

and then try something like:

(setf rrh (gen-repeat 3 rh))

;or

(setf rrh (gen-repeat '(3) rh))

neither gives me what I'm looking for.

However, I notice that if I evaluate

 

(setf rrh (gen-repeat 3 (list (first rh))))

then I get the correct result for the first measure.

 

Therefore, doing something like this gets me what I was looking for:

 

(setf rrh (gen-divide 8 (flatten
      (mapcar #'(lambda (n) (gen-repeat 3 (list n))) rh))))

 

But surely there's a better/simpler way to repeat bars in omn format.

 

If anyone has insights, I'd be most appreciative.

 

thanks, Michael

 

 

 

 

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As I've played around I hit on this, which works if the repetition is always the same number (it would obviously be nice to do this with cycles of numbers, etc)...and of course, I continue to be sure there's some much easier way to do this that I don't know about yet...

;;this helper function returns a list of lists one level deep
(defun remove-nested (lst)
  (if (endp lst) 'nil
    (append (car lst)
            (remove-nested (cdr lst)))))

;;x is number of repetitions per bar
(defun repeat-omn (lst x)
  (remove-nested 
    (mapcar #'(lambda (n) 
                (gen-repeat x (list n)))
            lst)))

(setf rrh (repeat-omn rh 3))

 

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(setf r-transitions1 '((e (e 1) (-e 3)) (-e (e 3) (-e 1))))
(setf marked (gen-markov-from-transitions r-transitions1 :size 120))
(setf r1 (length-span (gen-repeat 20 1) marked :omn t))
(setf pitches '(c4 eb4 f4 g4 bb4 c5 eb5))
(setf chords (chord-interval-add '(12) pitches))
(setf rh (make-omn :length r1 :pitch chords))
(setf rrh (omn-to-time-signature (gen-repeat '(3) rh) '(4 4)))

or

(setf rrh (assemble-seq (mapcar #'(lambda (x) (gen-repeat 3 (list x))) rh)))

 

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