%Time Domain Verification
clc;clear;close all;
fm=50;fs=40;%Under sample(fs=40), Nyquist (fs=100), OverSampled (fs=500)
t=0:0.0001:10/fm;
y=cos(2*pi*fm*t);
subplot(3,1,1);
plot(t,y);
title('Continuous Time Signal');
xlabel('Time');
ylabel('Amplitude');
n=0:1/fs:10/fm;
ys=cos(2*pi*fm*n);
subplot(3,1,2);
plot(n,ys);
title('Sample Signal');
xlabel('Time');
ylabel('Amplitude');
yr=interp(ys,1);
subplot(3,1,3);
plot(n,yr);
title('Reconstruct Signal');
xlabel('Time');
ylabel('Amplitude');

%Frequency Domain Verification
clc;clear;close all;
fm=50;fs=40;%Under sample(fs=40), Nyquist (fs=100), OverSampled (fs=500)
n=0:1/fs:10/fm;
ys=cos(2*pi*fm*n);
x=fft(ys);
N=length(ys);
xmag=abs(x);
xmagh=xmag(1:N/2);
f=(1:N/2)*fs/N;
plot(f,xmag);
title('Frequency Domain Signal');
xlabel('Frequency');