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Ratios to rhythm

Hi all!

Some questions related to rhythm. I try to get the OM quantification logic and how it works without using trees…
Is it possible this list: (1/16 17/24 65/48 2), where the limits, 1/16 a sixteenth note, and 2 a half note and all the middle parts been expressed as rhythm in OM?
This is a supposed rallentando from a start list of (1 2 3 4) numbers scaled to 1/16 low and 2 high.
Are there any interesting patches for rhythm to study? Any rhythm libraries?

Thank you a lot in advance!!!

Dimitris

Hi Dimitris,

Yes it is possible of course. Just put your list in the second input of a Voice and evaluate it.
For more material you can check the links found on this page:

On rhythm in om there is an interesting view here:
http://www.algorithmiccomposer.com/search/label/openmusic

and here:

Best
K

Dear Karim thank you a lot for your answer.

Unfortunately I still can not get the results I intend.

I include the patch below.

I scale the list with om-scale (1 2 3 4) from 1/16 to 2.

The scaling results into:(1/16 17/24 65/48 2).

I quantify the results and I get the first picture values, where I wanted the second picture ones:



It has to do with the way that OM-Quantify understands the values (the 2 as 8 beats instead of 2. The same goes for the in between values).
Is there any other suggestion to get the expected values?

Thank you a lot in advance!

Dimitris
2_19_Accel-Rit 2D.omp (14.7 KB)

Hi Dimitris,

I am a little confused about what you want. Is you need your symbolic representation above, you don’t need at all to quantify whatever. Beside, the proportion are the following:
(1/16 1/8 11/32 1/2) base on a whole note division, and you can “write” it directly as follows:


Now on the contrary if you need to “quantify” durations as to have an accelerando or ritardando from one duration to another, you can use this suggestion:

Notice in this example:

  1. interpolation can give you n steps to your rit. You can also benefit of a linear or nonlinear interpolation (see intepolation help)
  2. If we use ratios as multiple of a whole note and a tempo of 60, we then multiply the output of interpolation by 4000 (ms)
  3. In the quantification (omqunatify) you can choose your resolution. Here we have set it to 1/32 note. Further more, we have "augmented the measure by 5/4 since omquantify sometimes behaves weirdly and crops the last duration.

Hope this helps.

Best
K

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Hi Dimitris and Karim,

An alternative would be to go through the circular representation of rhythms available in OpenMusic, with the OM class n-cercle and associated n-cercle to Voice conversion functions. Your first hand-written example would then become:

(1/16 17/24 65/48 2) = 1/48 (3 34 65 96),

which gives you the rhythmic pattern (3 34 65 96) that can easily be translated into a circular representation. With a bit of patching, you can set it into a Voice in order to musically represent the rhythm in the most parsimonious, and interpreter-friendly way.

And just for fun, here’s how your first hand-written example looks in a circular representation:

All the best,
António

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