bquadmax_update

Algebraic solution to extrema in a frequency response of a digital biquad filter.

The code implements a fully equation based solution for the (possibly) two extremal frequencies and their magnitudes in a digital biquad filter. Optional code at the end allows verification via the Fvtool.

This code has been put into C code with equvilent results and is offered as way to test biquad responses when plotting isn't an option.