• pseudo
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    18 hours ago

    That matrix of zeros with one in diagonal is called the matrix of identity.
    It is famous because when doing multiplication on matrix or vector, it acts likes 1 on “normal” number:
    x times 1 is x anyMatrix times Identity is anyMatrix.

      • pseudo
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        18 hours ago

        You are right. I will correct it.

          • pseudo
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            14 hours ago

            I need to freshen up on my linear algebra. I don’t remember on which sense it goes but I think if you swap the factors, you’ll have to you transpose the matrix x to keep the same result.

      • MBM@lemmings.world
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        18 hours ago

        Huh? Identity times anyMatrix is also anyMatrix. The matrix just has to have the right dimensions