[pd] [noise~],[expr~], questions

[Damian Stewart]

hard off wrote:
> sorry, i have a few questions today, i know it's bad from to ask them
> all in one thread, but i don't want to start too many threads.
> 
> 
> question 1)
> how do you multiply a signal by a power of n ?  can you do it with expr~?

do you mean take a signal to the nth power?

to square a signal (ie signal^2) do this:

[osc~]
|\
| \
[*~]
|
[dac~]

to cube the signal, take the output of the [*~] above and pass it through 
another [*~] which takes the original signal [osc~] as its other input.

> question 2)
> is there a list of the functions that i can use with expr~ (and expr)
> ?  i have seen many of these functions in other peoples patches, but
> can't find them in pd's documentation.

i'd be interested in this myself..

> question 3)
> i want to insert a percentage of random noise into a signal.  ie, for
> every oscillation of an [osc~]  i want 25% of the samples to be
> converted into noise.  the level and position of the noise should be
> random, but 25% of the samples in each oscillation must be be
> converted into noise.
> any idea how to do that?

i'm not sure i understand what you mean by 25%. do you mean you want to mix 
an osc~ signal and a noise signal with the noise being 25% of the amplitude 
of the osc~ signal? or do you want to have an osc~ signal interspersed with 
noise such that the noise occurs 25% of the time and the osc~ the other 75%?


-- 
Damian Stewart
+64 27 305 4107

f r e y
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