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Questions about Matrices

  1. Dec 21, 2009 #1
    Hi all ,

    I'd like your help with some actions taken with matrices .
    if A=[1 2 3 ; 4 5 6 ; 7 8 9 ] and C=[1 3 -1 ; 2 4 0 ; 6 0 1 ]

    what is the difference between A/C and A\C ?
    what does it mean A./A ? what is A. ? matlab doesn't give me an answer when I write A.

    thanx
     
  2. jcsd
  3. Dec 22, 2009 #2
    Think of A/C and A\C as more efficient ways of calculating A*inv(C) and inv(A)*C, respectively.

    A. doesn't mean anything. It's ./ that means something. ./ means divide element by element. Adding the . to an operator means to do it element by element. For example A*A is matrix multiplication while A.*A means just multiply the corresponding elements.
     
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