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Signal Processing

  1. Dec 12, 2007 #1
    Hi,

    I am pretty new to Matlab and am trying to reduce the noise of a particular signal. I found this pdf online and found it to be helpful. However, I am having trouble figuring out what the freq=(0:79)/(2*n*dt) means. More specifically the 0:79 bit. Any help would be much appreciated.

    Referring to: http://www.math.uic.edu/~jan/mcs320s07/matlec7.pdf
     
  2. jcsd
  3. Dec 12, 2007 #2

    marcusl

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    (0:79) defines a string of the numbers from 0 to 79. The line defines "freq" as these numbers divided by the denominator.
     
  4. Dec 12, 2007 #3
    Thanks for the reply. I apologize that my question wasn't clear. I meant why are they choosing 80 samples?
     
  5. Dec 12, 2007 #4

    marcusl

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    I think it's just a choice of convenience. If you plotted all 401 points in the spectrum, the peaks at bins 2 and 4 would be indistinguishable from the y axis. He's just zooming in on the region of interest.
     
  6. Dec 12, 2007 #5
    that's exactly what i figured. thank you.
     
  7. Dec 12, 2007 #6

    vky

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    Hi, jus came across this thresd, noticed your matlab lecture notes seems very handy. I'm wondering if I would be able to get my hands on the set of notes your using. Wil be much apreciated if so. Thanks.
     
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