[PD] Random - Different seed each time the patch is loaded

Charles Henry czhenry at gmail.com
Fri Sep 5 05:26:39 CEST 2008


On Thu, Sep 4, 2008 at 5:09 PM, Peter Plessas <plessas at mur.at> wrote:
> * Charles Henry <czhenry at gmail.com> [2008-09-04 23:53]:
>> On Thu, Sep 4, 2008 at 4:29 PM, Peter Plessas <plessas at mur.at> wrote:
>> > Perhaps i am getting you wrong, but if i would want different behavior
>> > each time i'd open that patch, the noise from your adc~ would do that,
>> > bc it is surely different (thermal noise, etc) every time.
>> > (provided you switched your dsp~ on in advance). :-)

> That is right, for really large numbers and critical applications the
> noise from the soundcard might not be white enough!

Actually, it's not the whiteness of the noise which is important.
Whiteness of noise simply means that the samples are not correlated
with each other with respect to time.  The key is the distribution of
a random variable, namely the instantaneous value of the noise at a
single point in time.

Since the noise values tend to be close to 0, the values are un-evenly
distributed.  I'm really just pointing to the advantage of using a
uniformly distributed random variable for choosing seeds.

Of course, now that you have me thinking about it :) ,  we could
transform our distribution for the noise into a uniform distribution,
like using the Box-Muller method backwards.




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