# MATLAB: How to create a 2-D plot to validate filter characteristics

anaylsisaudiodafxdsp

I am running a test signal (white noise) through filter so that i can validate the frequency response and magnitude.
Below is the code I'm using to test the filter
%Test 1Fs = 44100x = randn(1,44100); % Signal = randn (fs*dur,1) shall generate 1 channel signal with certain sampling frequency and duration[b1,a1]=fourbandEQ(30,0,1,  300,0,1,   1000,0,1,   5000,0,1,  Fs);y = filter (b1,a1,x); % y = filter(b,a,X) Y is output signal, X is input signal, b is array of%denominator coefficients , a is numerator

Fn = Fs/2;tf = fft(y)./fft(x);Fv = linspace(0, 1, length(tf)/2+1)*Fn;Ix = 1:length(Fv);figure(1)subplot(2,1,1)plot(Fv, abs(tf(Ix)))gridylabel('Amplitude')subplot(2,1,2)plot(Fv, angle(tf(Ix)))gridxlabel('Frequency')ylabel('Phase')