Runge-Kutta is for integrating functions that you know a formula for. So, at least in terms of signals in Pd, there's nothing better than the simple recursion formula (x is input, y is output): y[n] = y[n-1] + x[n]
Now, you may also want to scale by the sample rate y=integral(0 to t, x*dt) Then, it's just y[n] = y[n-1] + x[n]/44100 (or whatever sample rate) In z-transform terms we get: Y(z) * (1 - z^-1) = X(z) or Y(z) = X(z) / (1 - z^-1) which tells us we have a single real pole at z=1 So, the object I think you want is just [rpole~ 1] And you can apply the scaling by the samplerate as needed. for messages, I don't know. To integrate them over time, you would have each value multiplied by the time in between messages. Chuck On Wed, Aug 17, 2011 at 4:10 PM, Jeppi Jeppi <[email protected]> wrote: > Hi all! > I would like to know whether there is any object or abstraction available to > perform numerical integration (at control or audio rate, whatever) for Pd. > Any examples around there? > Thanks in advance! > Josep M > _______________________________________________ > [email protected] mailing list > UNSUBSCRIBE and account-management -> > http://lists.puredata.info/listinfo/pd-list > > _______________________________________________ [email protected] mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
