[PD] better tabread4~

[Matt Barber]

>
> You can see that a lot of terms cancel.  So, we can also change the
> type of problem and work backwards, setting the spectrum and working
> backwards to find the corresponding impulse response, and
> interpolation polynomial.
>


Chuck, thanks for the explanation!  One question about this -- would
working back from the spectrum possibly mean that you wouldn't
necessarily match any of the points (would this mean you could say the
impulse response would not have a value of 1 at t=0)?  This would be
an interesting proposition, and maybe it might help temper the
tendency of polynomial interpolation to deliver values >1 or <-1 when
the curve has a maximum or minimum between samples?  I'm not sure if
that would be the result, but I like the sentiment.  =o)

Anyway, thanks again.

Matt