《DSP using MATLAB》Problem 2.18

function [y, H] = conv_tp(h, x)
	% Linear Convolution using Toeplitz Matrix 
	% ----------------------------------------------------
	% [y,H] = conv_tp(h, x)
	%  y    = output sequence in column vector form 
	%  H    = Toeplitz matrix corresponding to sequence h so that y = Hx 
	%  h    = Impulse response sequence in length(h)*1 column vector form 
	%  x    = input sequence in length(x)*1 column vector form 
	%
for i = 1:length(h)
	c(i) = h(i);
end

for j=(length(h)+1):(length(x)+length(h)-1)
    c(j)=0;
end


r(1)=h(1);

for k=2:length(x)
    r(k)=0;
end

H=toeplitz(c,r)
y=H*x;
end

%% ------------------------------------------------------------------------
%%            Output Info about this m-file
fprintf(‘\n***********************************************************\n‘);
fprintf(‘        <DSP using MATLAB> Problem 2.18 \n\n‘);

banner();
%% ------------------------------------------------------------------------

nx1 = [0:4]; x1 = [1, 2, 3, 4, 5];  
nh1 = [0:3]; h1 = [6, 7, 8, 9];

[y1, H] = conv_tp(h1‘, x1‘);


y1