[SciPy-User] usage of symiirorder1

[Neal Becker]

Neal Becker wrote:

> symiirorder1 (and 2) are lacking in documentation.
> 
> I suggest the basic usage might be:
> 
> set a time constant k:
>         k = 0.001
>         r = symiirorder1(np.abs(error), (k**2), 1-k)
> with this choice of parameters, the filter gain will be unity

Similarly, what might be reasonable choices of parameters for symiirorder2?
Suppose I want a 2nd order filter, with bandwidth B, and damping D?  How 
does this relate to the parameters of symiirorder2?