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

Charles Henry czhenry at gmail.com
Thu Sep 4 23:53:51 CEST 2008

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). :-)
> rgrds, PP

Yes, your method would work pretty well.  The individual samples of
the noise are correlated with each other (thermal noise is not white).
 But when you take a single sample at a given time without knowing the
previous values, that correlation can be ignored, and you would
generate a completely independent random number, drawn from the
distribution of the noise.  The only problem is if the noise is very
narrowly distributed, so that you only recieve one of a few possible
choices of the seed value.

Compared to using time/date:  the noise we can assume is distributed
about 0 with a Gaussian (continuous) or approximately a Binomial
(discrete) distribution.  On the other hand, time/date are distributed
uniformly.  You would have a greater variance of seed values from
using time/date than by using noise from adc~, and thus, a lesser
degree of correlation between instances.

I like your idea, because you really get a completely independent
random variable--but I would try to convince you that, for a large
number of instances, you would see some correlations in the sequences.


More information about the Pd-list mailing list