Parameters
double lowStopbandFreq
Lower stopband corner frequency (in Hz).
double lowPassbandFreq
Lower passband corner frequency (in Hz).
double highPassbandFreq
Higher passband corner frequency (in Hz).
double highStopbandFreq
Higher stopband corner frequency (in Hz).
double passbandRipple
Maximum allowed passband ripple.
double stopbandAttenuation
Minimum required stopband attenuation.
Return
ValueTuple<Double[], Double[]>
IIR coefficients.