20Concepts Lesson 07 - More About Numbers

From Cycling '74 Wiki
(Difference between revisions)
Jump to: navigation, search
(Web Links)
Line 58: Line 58:
== ''Web Links'' ==
== ''Web Links'' ==
(Needed: text and links)
[http://algorithmiccomposer.com/ Algorithmic Composer Blog]
== ''Exercises'' ==
== ''Exercises'' ==

Revision as of 21:25, 5 December 2012

(Needed: Example Video)

(Needed: Overview Text)

(Needed: Fixture Patches with download)

Random Numbers


The use of chance in the arts can fall under different headings such as random, stochastic, aleatoric, or probabilistic but they all share a common theme - events which result in non-deterministic outcomes some or all of the time.

While the use of chance has been in the arts for many centuries it was not until the 20th century that the Western Art world started taking a more concerted look at the role of randomness in the arts. In music people like John Cage and Iannis Xenakis developed compositional techniques for random and probabilistic composition and performance, authors such as William Burrows experimented with cut-up techniques, Dadaist painters used various random techniques to create anti-art and later on Jackson Pollack used a mixed of intent and randomness in his Action Painting. In the contemporary arts world the use of chance is seen as a general principle that can be employed at will. In the Digital Arts the use of different random techniques is often a fundamental requirement to producing specified goals.








To meet this requirement use the urn object. Using the urn object can be thought of like putting names in a hat. After a name is randomly chosen it is also removed from the hat. This prevents the possibility of repeating the same value. When urn has exhausted all it's possibilities it needs to be reset - which is the digital equivalent of putting the names back in the hat.



The drunk object outputs what is called a random walk or a drunkard's walk. As far as I know this is a first order or simple Markov chain. Drunk takes two arguments the first being the maximum number that can be output and second the step size between consecutive numbers. For example if the drunk object has the arguments 100 and 5 then the first number output will be a random number between 0 and 99 and all subsequent numbers will be within 5 numbers +/- of the last number output.

This is useful if you need a random meandering path rather than big random jumps. A typical use would be to give drunk a maximum argument of 24 and a step size of 3 or 4 and then connect it to a MIDI output. The result will be numbers going up and down two octaves with step size no greater than three, kind of like playing runs on a piano. If you quantize the note numbers with a musical scaler it can be quite effective as a tool for simple modal improvisation.


(Needed: text)

Filtering Repetitions and Defining Boundaries

  • change
  • clip
  • rslider

(Needed: text)

Web Links

Algorithmic Composer Blog


(Needed: text and exercises)

by Darwin Grosse and Cory Metcalf