T=pi/32;
t=0:T:2*pi;
x=exp(-t).*sin(4*t);
h=(1/4)*((t>=(pi/4))-(t>=(3*pi/4)));
figure(1)
subplot(3,1,1)
plot(t,x)
subplot(3,1,2)
plot(t,h)
y=conv(x,h);
t1=0:T:4*pi-1;
subplot(3,1,3)
plot(y)