%%This function is written to calculate the covolution of continous signals.
%% in the function arguments, cconv(x,h), note that :
%%     x    : input signal
%%     h    : impulse response of the system.
%%     Note : for any signals x(t) and h(t) and convolution of them 
%%               y(t)=x(t)*h(t),you should set the axises range and time range
%%               in lines : 20,24,27,31,


  %% *****************************************************************************
  %% *                       by : Davood Shaghaghi                               *
  %% * Electrical Engineering Department, Hamedan University of Technology(HUT)  * 
  %% *                 Email: davood.shaghaghi@gmail.com                         * 
  %% *                           April 14, 2010                                  *
  %% *              Copying is permitted with source citation!                   *
  %% *****************************************************************************
function []=cconv(x,h)
tic
syms t T
t=-3:.1:6.5;
f= subs(x,T).*subs(h,t-T);
y=int(f,T,-inf,inf);
subplot(3,1,1)
ezplot(x,[-1.5 1.5])
title('input signal,x(t)')
subplot(3,1,2)
ezplot(h)
title('impulse response,h(t)')
subplot(3,1,3)
plot(t,y);
axis([-3 3 -1 1])
title('output signal,y(t)')
shg
beep
toc/60
end