Can u help me with this question about Fourier?

Use MATLAB to verify that the product time and bandwidth of a discrete time square wave is approximately independent of the number of nonzero values in each period when the duration is defined as the number of nonzero values in the square wave and the bandwidth is defined as the width of the main lobe. Set a period of the square wave as

x[n] = {1, 0 <= n < M {0, M <=n <= 999

Evaluate the bandwidth by first using the fft and abs commands to obtain the magnitude spectrum and then count the number of DTFS (Discrete-Time Fourier Series) coefficients in the main lobe to M = 10, 20, 40, 100, and 200.

[Jan]

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