SinwaveConvolution.m

clc; #... Clear command line
clear all; #... Clear variables
close all; #... Clear figures

n = 0:1/80:1; #... Sampling frequency = 80 Hz
h = 5*sin(2*pi*4*n);
x = 7*sin(2*pi*3*n);

z = []; #... To store values of x*h
for i = 1:length(x)
  xh = h.*x(i); #... Multiply x(i) with all values of h
  z = [z; xh]; #... Store xh in the next row of z
endfor

[r c] = size(z); #... Row & column of z
ans = zeros(1,r+c-1); #... Convolution result will be stored here

for i = 1:r
  for j = 1:c
    ans(i+j-1) = ans(i+j-1)+z(i,j);
  endfor
endfor

z1 = 2; #... 0©th index of x
z2 = 3; #... 0©th index of h
index = (z1+z2-1); #... 0©th index of ans
n = -(index-1):length(ans)-index; #... time(n)

disp(ans);
plot(n, ans);