linear and circular convolution

%syms p q % needed only when poly2sym() is used
run_loop=1;
while run_loop==1
x=input('enter 1st sequence');
h=input('enter 2nd sequence');
x_str=char(int2str(x));
h_str=char(int2str(h));
%x_str=char(poly2sym(x,p)); %this returns the sequence as a polynomial
%h_str=char(poly2sym(h,q));
N1=length(x);
N2=length(h);
%N=max(N1,N2)
N=(N1+N2-1) % circular convolution using N=max(N1,N2) will result in aliasing of (N2-1) points if N1 not=N2
y=conv(x,h)
yc=cconv(x,h,N)

n=0:1:N1-1;
subplot(2,2,1);
stem(n,x)
xlabel('No. of samples');
ylabel('amplitude');
title(['First sequence:',x_str]);

n=0:1:N2-1;
subplot(2,2,2);
stem(n,h)
xlabel('No. of samples');
ylabel('amplitude');
title(['Second sequence:',h_str]);

n=0:1:(N1+N2)-2;
subplot(2,2,3);
stem(n,y)
xlabel('No. of samples');
ylabel('amplitude');
title('Sequence for linear convolution');

n=0:1:N-1;
subplot(2,2,4);
stem(n,yc)
xlabel('No. of samples');
ylabel('amplitude');
title('Sequence for circular convolution');
run_loop=input('continue with another convolution? 1(YES), 0(NO):')
end