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Matlab Nyquist Problem

  1. Dec 8, 2008 #1

    I was curious if anyone else had run into this issue.

    It seems that if you try to do a nyquist diagram when there is an s-term by itself in the denominator (a pole at zero), Matlab mistakenly tries to use that value (instead of detouring around it), and produces an incorrect plot.

    For example,

    G(s) = -----------------
    ..........(s)(s + 3)(s + 5)

    Will produce the wrong nyquist plot.


    The same website provides a new function called http://www.engin.umich.edu/group/ctm/extras/nyquist1.html" which was supposed to fix the problem, but the code has an error (it's kind of outdated), and the code is a little over my head in terms of troubleshooting.

    I know it's a long shot, but I was hoping someone else had run into this and was able to provide a solution.
    Last edited by a moderator: Apr 24, 2017
  2. jcsd
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