《DSP using MATLAB》Problem 2.17

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%%            Output Info about this m-file
fprintf(‘\n***********************************************************\n‘);
fprintf(‘        <DSP using MATLAB> Problem 2.17 \n\n‘);

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

[y1, ny1] = conv_m(x1, nx1, h1, nh1);

ny1
y1

figure(‘NumberTitle‘, ‘off‘, ‘Name‘, ‘Problem 2.17‘)
set(gcf,‘Color‘,[1,1,1])                  % 改变坐标外围背景颜色

subplot(3,1,1); stem(nx1, x1); title(‘x1 sequence‘);
xlabel(‘n‘); ylabel(‘x(n)‘) ;
grid on
subplot(3,1,2); stem(nh1, h1); title(‘h1 sequence‘);
xlabel(‘n‘); ylabel(‘h1(n)‘);
grid on;
subplot(3,1,3); stem(ny1, y1); title(‘y1=x1*h1 sequence‘);
xlabel(‘n‘); ylabel(‘y1(n)‘);
grid on;