I'd say, you can't go wrong with fexpr~. Works for any kind of discrete time difference equations & has many amazing /creative uses.
Chuck On Thu, Mar 20, 2008 at 6:40 PM, Andy Farnell <[EMAIL PROTECTED]> wrote: > > I have a problem, that is partly of my own making and need to air > this on the list for advice. This isn't a rant, just a frustrating situation. > > As some of you know I have been working on a textbook for Pd for some time. > In the final stages and adding the practical exercises and the problem is > this: > > > The book is completely for vanilla Pd to keep things simple and I really > don't > want to change this. > > I have three crucial exercises that use [delta~] > > [delta~] does not exist in vanilla Pd > > [delta~] must be recreated _EXACTLY_ as the external behaves. > > It IS possible to recreate [delta~] exactly using [z~] > > [z~] does not exist in vanilla > > It is not, as far as I can see, possible to emulate [delta~] using > [rzero~] or any other signal domain method, in a way that doesn't > confuse the hell out of the reader or provide unsatisfactory results. > > I am left with these options: > > > 1) Drop three of the most interesting exercises from the textbook. > > 2) Change my policy and make the textbook require pd-extended on account of > only _one_ object! > > 3) Find a vanilla replacement for [delta~] that is simple. (less than three > objects) > > 4) Convince Miller to include [delta~] in vanilla > > 5) Convince Miller to include [z~] in vanilla > > > To the list: I'm hoping some bright spark will solve (3). Be warned, it > isn't as > simple as it seems, AFAICS. [rzero~] should provide a differentiator > response in > theory. In practice dealing with the offsets and scales ruins the whole show > and > leads to over-complex and unstable patches. Using [biquad~] is extremely > confusing > to most readers and I don't want to do this. You cannot obtain a single > sample delay > using [delwrite~] as far as I know, if you can it certainly means > [samplerate~] must > be added to all patches to make sure they run at different sr, which is > mucho annoying. > > To Miller: Please consider admitting [z~] or [delta~] (I actually prefer the > former > because it is more educational to see differentiator built from sample delay) > into the vanilla distro. This would need to be time for release quite soon. > I'm sure > it would greatly benefit Pd to do this. > > Best regards 2 all, > > Andy > > > > > > > > > > -- > Use the source > > _______________________________________________ > [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
