You have tools to do the DTFT (dtft, magnitude_response, etc...).  What I
am after is for you to see that the DFT is a "sampled" version of the DFT.
The "hold on" MATLAB command superimposes the N points of the DFT unto the
DTFT plot (which is continuous in frequency).

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Q: How do I get the radar file into MATLAB?
A: type:

        load radar
        who

and you'll see the vector's name, length, etc...

If you are using C, you'll need to write some code to read floats from a file
and put them in an array.  The floats are tab-delimited.
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Values for the DTFT for Prob. 1 are on p. 52 of your text.  Since our
signal values are 0.2 as opposed to the values in the book which are 1, you
should expect the plot to be 1/5 that of the plot in the book.
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