Date: Jan 19, 2013 1:36 AM
Author: Greg Heath
Subject: Re: The DFT of a Rectangular Window & The Effects of Zero Padding a Signal
"PUPR" wrote in message <kdc5ko$l5m$1@newscl01ah.mathworks.com>...

> Hello, I'm new at MatLab. I need help solving the following examples. I use the command "doc" to access the library, but I'm not shore if it is correct how I implement the commands. I try to solve the first example:

>

> 1) Plot the 4-point magnitude DFT of the following pulse w[n] = [0,1,2,3]

> (Use the FFT command in MATLAB.)

>

> dft_data = [0,1,2,3];

> FF_T=fft(dft_data);

> m = abs (FF_T);

> stem(m);

>

> 2) Conveniently zero pad the signal in order to plot the 8-point DFT, the 16-point DFT and the 128-point DFT.

Try

help fft

Greg