On Sun, Sep 21, 2008 at 8:56 AM, Claude Heiland-Allen <[EMAIL PROTECTED]> wrote: > Damian Stewart wrote: >> >> Charles Henry wrote: >> >>> There is no zero at z=0. I'm not sure about this one--but it seems as >>> though it's impossible to have a zero at z=0? > > a zero at z=0 is a delay of 1 sample, so in: > > y = a x(0) + b x(-1) + c x(-2) + d y(-1) + e y(-2) > > there is a zero at z=0 if a == 0, > and two zeros at z=0 if a == 0 and b == 0 > > (iirc)
z^-1 is the unit delay operator.... so, Y(z)=z*X(z) means y(n) = x(n+1) while this is not impossible... it's non-causal. For real-time filtering, you can't already know the sample that comes next. I've been thinking about it for a little while now. I hope we can figure it out Chuck _______________________________________________ [email protected] mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list
