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Optimization Code

  1. Aug 19, 2005 #1
    OK, here is the situation.

    I am supposed to write optimization code in Matlab to determine which of two missions an airplane should perform. There are three total, but one of them has been decided on. So I need to determine which of the other two I should do.

    The problem is that I have never written this type of code before, so I have no clue what to do.

    Could someone give me a good resource I can use as a starting point to writing this code?
  2. jcsd
  3. Aug 19, 2005 #2
    um i think you need to put parameters/variables/criterion that your using so that people can be more descriptive. ie is it a airplane path like TSP/Hcycles problem?
  4. Aug 19, 2005 #3
    ok, I need to minimize the weight as much as i can.

    one mission involved flying up to 10 liters of water, and is scored by number of laps completed ^2, ie 5 laps = 25 for score

    the other is carry 96 tennis balls for 2 minutes, and this can be any number, as long as all 96 fly. scored by 1/RAC where RAC = airframe + battery weight.

    The plane already will carry 48 tennis balls and 4 liters of water.
  5. Aug 19, 2005 #4
    There is an optimization function built in.

    What you want to do is define a goal function. The matlab function will
    minimize that goal function (If you want to maximize it, put a minus sign in front
    of it.)

    Then there are some number of unknowns. You goal function is a function of the
    unknowns and matlab will find particular values for the unknowns so that the
    goal function is a minimum.

    Try "help fminsearch"
  6. Aug 19, 2005 #5

    is fminsearch in standard matlab or is it in a toolbox?
  7. Aug 20, 2005 #6


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    ... if you have the optimization toolbox then you've a number of great tools available. Fminsearch is for unconstrained nonlinear optimization and is a standard function.
  8. Aug 20, 2005 #7
    ok thanks.

    sounds like i may want to consider using the optimization toolbox, especially because i need this code done in two weeks.
  9. Aug 20, 2005 #8


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    Science Advisor
    Gold Member

    ... and depending on the degree of nonlinearity and in case you've 'complex' constraints you may have to implement, the optimization toolbox rules.
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