%% Plot Poles and Zeros of Fourth-Order Filter
% Create a fourth-order IIR digital filter with a cutoff frequency of 0.6. Plot the poles and zeros of this filter.

[b,a] = ellip(4,.5,20,.6);
zplane(b,a)

%
% Quantize the filter by passing a fixed-point input through the filter algorithm. Plot the quantized and unquantized poles and zeros associated with this filter.

iirFilt = dsp.IIRFilter('Numerator',b,'Denominator',a);
in = fi(randn(15,6),1,15,3);
out = iirFilt(in);
zplane(iirFilt)

% Copyright 2012 The MathWorks, Inc.