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a tiny function idea

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(defun and-span (n a b)
  (and (>= n a)
       (<= n b)))

(and-span 13 12 45)
=> t


(and-span 2 12 45)
=> nil

 

 

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    • By spuki
      Hallo,
      newbie here 🙂
      I'm just starting with OM and playing around with the tutorials.
      I slightly changed tutorial #4 and run into something strange.
       
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      Best,
      Sebasian
      (setf pitches (gen-repeat 5 '(c4 cs4 fs4 g4 c5 cs5))) (setf transposed-pitches (gen-repeat 5 (pitch-transpose -24 pitches))) (setf lengths (span pitches '(e))) (setf lengths-rests (length-weight lengths :weight '(2 1) :seed 12)) (setf left-lengths (reverse lengths-rests)) (setf piano-righthand       (make-omn        :length lengths-rests        :pitch pitches        :velocity'(mp))) (setf piano-lefthand       (make-omn        :length left-lengths        :pitch transposed-pitches        :velocity '(f))) (setf timesigs (get-time-signature left-lengths)) (def-score lesson-4            (:key-signature 'chromatic             :time-signature '( 5 8 )             :tempo 190             :layout (piano-layout 'piano-rh 'piano-lh))     (piano-rh    :omn piano-righthand    :channel 1    :sound 'gm    :program 'acoustic-grand-piano)     (piano-lh    :omn piano-lefthand)   )  
    • By Deb76
      Hello, 
      Somewhat stupid question but I do not find a function that would allow me to reorder a sequence of pitches.
      Let me explain, on a forum where Messiaen's limited transposition modes are discussed, I wanted to show that with Opumodus we could very easily analyze the modes and recreate them. I have no problem with those who are in total symmetry and divisible by two, but if I take the mode 3: (c4 d4 eb4 e4 gb4 g4 ab4 bb4 b4), using the function pitch-transpose-start I get in the end the mode but according to the postponement of the intervallic structure on c4 d4 ab4 is => ((c4 e4 gs4) (d4 fs4 bb4) (eb4 g4 b4)). I tried to reorder with the function pcs-normal-order the mode is reordered but with however the c4 in last position: (d4 eb4 e4 fs4 g4 gs4 bb4 b4 c4). Now, I suppose there is a function that makes it possible to obtain the right disposition. What is it ?
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    • By JulioHerrlein
      In my Dissertation, I worked a way to convert every chord and set in a modulo 12 rhythm,
      so the entire catalog of FORTE are converted to rhythms, following the steps of Babitt:
       

       
      As a hardcore serialist, Babbitt was interested in converting 12-tone rows to rhythms, in a kind of 12-tone rhythm theory.
      Below, Wuorinen show one example of a typical Babbitt idea:
       

       
      For the sake of explaining my idea of function, it's important to have in mind that for Babbitt, the order of the
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      Even voicings can be converted in longer Rhythms (the more spread the voicing, the longer the rhythm):
       

       
       
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      HERE IS THE POINT, for the sake of the new function !
       
      The note C (that I call Rhythmic Fundamental, the "root" of the rhythm) is being displaced, as
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      THE SET WRAP AROUND ITSELF, always forming 12 time-points (always twelve 16th notes),
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      THIS WAY IS MORE INTERESTING For Popular and Minimalist Repetition Music, as
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      Maybe Janusz or Stephane could find interesting to develop this kind of idea inside
       the software.
       
      All the best !
      Julio Herrlein
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