I want to edit this code to plot a time domain graph for the LPF, HPF, BPF filtered audio signal, how can I do it?

%Part 1 - (a, b, c)
[x, fs] = audioread('audio.wav')
x = x(:, 1);
n = length(x)
t = (0:n-1)/fs
n/fs
%Figure 1 - Time domain representation
figure(1)
plot(t, x)
grid on 
xlabel('Time(s)')
ylabel('Amplitude')
title('Time domain ')
%Figure 2 - Spectrogram 
figure(2)
spectrogram(x, 1024, 512, 1024, fs, 'yaxis')
title('Spectrogram')
%Figure 3 - Power spectrum density
figure(3)
w = hanning(n, 'periodic');
periodogram(x, w, n, fs, 'power')
title('power spectrum density')
%Play the audio
sound(x,fs)
%Part 2 - d
% define filters
freq = linspace(1000,(fs/2),500);
% 1 - LPF FIR / cutoff frequency 3 KHz
N = 64;
fc_lp = 3000;
B_lp = fir1(N,2*fc_lp/fs);
h=freqz(B_lp,1,freq,fs);
m_lp=20*log10(abs(h));
% 2 - BPF FIR / cutoff frequencies 2 and 5 KHz
N = 64;
fc_low = 2000;
fc_high = 5000;
B_bp = fir1(N,2*[fc_low fc_high]/fs);
h=freqz(B_bp,1,freq,fs);
m_bp=20*log10(abs(h));
% 3 - HPF  FIR /  cutoff frequency 4 KHz
N = 64;
fc_high = 4000;
B_hp = fir1(N,2*fc_high/fs,'high');
h=freqz(B_hp,1,freq,fs);
m_hp=20*log10(abs(h));
% apply filters on audio file
%LPF
x_lp = filter(B_lp,1,x); % filtered by LPF
figure(4)

figure(5)
spectrogram(x_lp, 1024, 512, 1024, fs, 'yaxis')
title('Spectrogram - LPF filtered signal')
figure(6)
w = hanning(n, 'periodic');
periodogram(x, w, n, fs, 'power')
title('LPF power spectrum density')
%BPF
x_bp = filter(B_bp,1,x); % filtered by BPF
figure(7)

figure(8)
spectrogram(x_bp, 1024, 512, 1024, fs, 'yaxis')
title('Spectrogram - BPF filtered signal')
figure(9)

x_hp = filter(B_hp,1,x); % filtered by HPF
figure(10)

figure(12)

[Walter Roberson]

http://www.mathworks.com/matlabcentral/answers/6200-tutorial-how-to-ask-a-question-on-answers-and-get-a-fast-answer

[Faisal Alrafaei]

i think the question is clear, what do you not understand?

[Walter Roberson]

You did not ask a question. You made a statement. You want to edit the code to do some particular thing. So go ahead and edit the code to do that.

Your code already claims to produce time domain graphs.

[Faisal Alrafaei]

i apologize i edited the question

[Walter Roberson]

Your titles in your code implies that your code already plots some of those things. What difference is there between what the code currently produces and the output you want?

(Remember, we do not have your data so we cannot run your code.)

[Faisal Alrafaei]

the time domain graph i have in my code is for the signal before filtering, i want the time domain graph for the signal after filtering in the 3 filters LPF, HPF and BPF

[Walter Roberson]

You already have

figure(5)
spectrogram(x_lp, 1024, 512, 1024, fs, 'yaxis')
title('Spectrogram - LPF filtered signal')

so it is not obvious what else you are looking for?

If you want to plot just the signal, then do that,

plot(t, x_lp)

with appropriate titles and figure numbers and so on.

[Faisal Alrafaei]

ok thank you