MATLAB: What is function of [ ] in this code

freqz

Here is the code

h1336=[];
L=50;
fs=8000;
fb=1336;
h1336 = (2/L)*cos(2*pi*fb*(0:L-1)/fs);
[H,F] = freqz(h1336,1,[],fs);

What does this bracket [ ] do in freqz command

Best Answer

It says "use the default value for the input N, the number of frequency points".

in freqz() that is 512.

[H,F] = freqz(h1336,1,[],fs);

is the same as:

[H,F] = freqz(h1336,1,512,fs);

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So that it is legal MATLAB indexing, however, I would say to avoid the for loop entirely. This is cleaner MATLAB.

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