fg_08_09.m

英文书《Digital Signal Processing with Examples in MATLAB》附带的MATLAB实例

% fg_08_09    MSE contour plot
N=150; m=1;
phi=cos(2*pi*[0:12]/12);
Phiff=[phi(1) phi(2); phi(2) phi(1)];
phifd=[phi(m+1); phi(m+2)];
b=Phiff\phifd;
min_mse=phi(1)-phifd'*b;

db=1.99;
b0=linspace(b(1)-db,b(1)+db,N);
b1=linspace(b(2)-db,b(2)+db,N);
mse=zeros(N,N);
for i=1:N,
   for j=1:N,
      mse(i,j)=1+[b0(i) b1(j)]*Phiff*[b0(i); b1(j)]-2*[b0(i) b1(j)]*phifd;
   end
end
sp_fig(1,5.5,5);
set(gca,'fontsize',14);
v=[.05 .15 .4 .8 1.8];
[c,h]=contour(b0,b1,mse,v,'b'); grid;
set(h,'linewidth',1.2);
clabel(c);
line([b(1) b(1)],[-5 5],'color','r','linewidth',1.5);
line([-2 4],[b(2) b(2)],'color','r','linewidth',1.5);
xlabel('b_0'); ylabel('b_1');
axis square;