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Matrix Division?

  1. Jun 29, 2008 #1
    As far as I know, matrices cannot be divided, you have to multiply one matrix by the inverse of the other...I believe.

    However, I am converting MatLab code into ANSI C and MatLab apparently divides two matrices. An example is the following...

    >>A=[1.5708 1.5708];
    B=[0.4937 0.7652];
    A/B

    ans =

    2.3846


    I have no idea how MatLab generated this answer. I try to find the inverse of the second matrix, but since it is a non-square matrix, MatLab denies my request. Can anyone aid me in figuring out how such an answer was calculated? Thank you in advance.
     
  2. jcsd
  3. Jun 29, 2008 #2

    cristo

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  4. Jun 29, 2008 #3
    I looked through that as well, but it says that it is equal to A*inverse(B)...but like I said, I cannot calculate the inverse of B. MatLab itself won't do it for me if I write the command line, so I don't see how it completes the matrix division calculation without finding the inverse of B.

    It also says that it is equivalent to A/B = (B'\A')'. But again, You have to divide two matrices, only here, it is the conjugate transposes of the two. So even if I find the conj. transposes of the two (which will basically move the rows into columns), I still cannot find out how they got 2.3846 as an answer.
     
  5. Jun 29, 2008 #4

    cristo

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    Presumably you need to decipher:
    It's too late here for me to get my head around that, but someone else will probably come along who can.
     
  6. Jun 30, 2008 #5
  7. Jun 30, 2008 #6
    THANKS!

    I had a look at this before, but I didn't really understand it, so I looked for simpler explanations. It took my stupid self about 30 minutes to fully comprehend what it was saying. I really had to read slowly. lol. It is very brief, but rightfully so. Not much more explaining needed once you get it. Thanks a bunch.
     
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