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Matlab help...!

Discussion in 'The Lounge' started by az-k5, Apr 25, 2006.

  1. az-k5

    az-k5 1/2 ton status

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    I have a matlab assignment I am working on. It is kicking my ace.

    I need to make a phase plot of a 3x3 matrix.

    I know how to do a 2x2, but adding a Z parameter is getting me.

    2x2 file of
    [-4,-6;-1,6]

    >>f=inline('(-4*x-6*y)./(-x+6*y)','x','y')
    f =
    Inline function:
    f(x,y) = (-4*x-6*y)./(-x+6*y)

    >> dirfield(f,[-2,2,-2,2],'line')

    >> axis equal tight

    What is the trick for a 3x3?

    Thanx
     
  2. midnitewarya

    midnitewarya Sounds like a problem for future me. Premium Member

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    I think this qualifies as tech.

    Yep, eyes are burning.

    This is tech.

    FOR SHAME!
     
  3. midnitewarya

    midnitewarya Sounds like a problem for future me. Premium Member

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  4. midnitewarya

    midnitewarya Sounds like a problem for future me. Premium Member

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    I think the main prob is the function. There is no way that will work with three variables in a 3x3.
     
  5. midnitewarya

    midnitewarya Sounds like a problem for future me. Premium Member

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    All linear algebra functions work only on 2-D matrices. You can not multiply two 3-dim matrices.
     
  6. az-k5

    az-k5 1/2 ton status

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    I know that function is useless on a 3x3 as it is a manipulation of dy/dx. I don't know how to use the plot3 command for a matrix.
     
  7. midnitewarya

    midnitewarya Sounds like a problem for future me. Premium Member

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    Was this a homework problem? I think it's a trick question. To solve for a 3x3 matrix, there is no way linear funtion could work. You can do it for an array, but not in a matrix.

    I'm probalby wrong, it's just been so dern long since I even thought about this stuff.
     
  8. midnitewarya

    midnitewarya Sounds like a problem for future me. Premium Member

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    You got me stumped dude, sorry. :crazy:
     
  9. az-k5

    az-k5 1/2 ton status

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    Ya it is a lab/homework. I am not positive I am supposed to plot the 3x3's but the professor made a big deal in class last week. Oh well, I am just running the program for the eigen values and eigenvectors and calling it a night. I still need to do a double mixing tank problem in the morning (god damn I love the week before the end of the semister).
     
  10. midnitewarya

    midnitewarya Sounds like a problem for future me. Premium Member

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    Brain hurting...flashbacks of studying and deadlines...must drink beer...

    I remember my final for that class. We had to make solitare. In three hours. It seems easy....

    I got a "B". I couldn't get the rows to lock, and you could cheat like crazy.

    Seems like forever ago...
     
  11. justhorsinaround

    justhorsinaround 3/4 ton status

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    You should really think of Jenn and just call ya yutz.

    You know the smart physics/science/astronomy gal I shack up with?
     

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