Forums > MaxMSP

random distributions

January 30, 2010 | 10:20 am

hi,
i’d like to create a list of random numbers with an exponential distribution in a range (i.e. 100 – 1000).
i was looking at the randdist object from cnmat, in particular the exponential or the exppow options,
but neither seem to do what i want. unless i’m doing it wrong, is there a better approach to acheive what i want somewhere?
many thanks,,


January 30, 2010 | 5:31 pm

As long as you express the random in a linear domain, and do the scaling afterwards, it will all work out well. Is this what you have in mind:

– Pasted Max Patch, click to expand. –

?

_
johan


January 30, 2010 | 8:35 pm

check out the beta distribution with randist. it will return values in the range 0-1., which you can scale – you can adjust the parameters a and b to get a range of different distributions, see here:

http://www.xycoon.com/beta.htm

———————————————
http://www.olilarkin.co.uk / http://olilarkin.blogspot.com


January 31, 2010 | 2:23 am

hi,
thanks for the help. seems i forgot about the scaling objects in max (silly).
the following comes close to the sound i was after,
which was to be the same as the sc3 command
x = { Ringz.ar(PinkNoise.ar(0.5), {exprand(300, 20000)}.dup(100)).mean}.play;
for some reason the sc3 version sounds "brighter", for lack of a better word,
any ideas why?
cheers again,,

– Pasted Max Patch, click to expand. –

January 31, 2010 | 8:34 am

Brighter would mean more higher frequencies. What if you’d draw random numbers as note values and then scale them to frequencies with mtof? It could also mean louder higher frequencies.

_
johan


Viewing 5 posts - 1 through 5 (of 5 total)