用Matlab编码将向量实现到矩阵

Question

Hey I am using a FIR filter on a signal. And I want to make the HF variable a matrix that contains the values of L in the variable hf. Like this:

HF = [hf1, hf2, hf3, hf4, hf5];

So that I can use the matrix HF in a subplot there I can get a view over the plots of each hf vector.

As you can see I got a tip of writing HF = [HF, hf]; that should implement the vector of hf to the matrix HF. But I can't get it to work.

Here is the code that I am using:

w0 = 9*pi/80;
for L = [5,10,50,100,1000]
   n = 1:L;
   dum = (sin(w0.*n))./(pi.*n);
   h = [fliplr(dum),w0/pi,dum];
   % stem(h);

   hfft = fft([h,zeros(1,(4096-length(h)))]);
   hf = log10(hfft.*conj(hfft)/(Fs*7)/2);

   HF = [HF,hf];
   %figure(7)
   %plot(hf(1:2048));
   %pause
end

r = 3;
c = 2;
Plotnb = 1;
for i=1:r
    for j=1:c
        subplot(r,c,Plotnb)
        plot(HF(:,Plotnb)); % Picks out the right column.
        Plotnb=Plotnb+1;
    end
end

% y2=conv(x,h);
% sound(y2,Fs);

Any tips would be much appreciated!

Thanks for the help
Daniel

Answer 1

Almost there, you just need to add

HF = [];

before entering the for loop. If you don't do that, the program fails on HF = [HF,hf]; because you are trying to concatenate hf with something that does not exist yet.