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## Re: FW: Scalars and Matrices:

 From: Mike Miller Subject: Re: FW: Scalars and Matrices: Date: Tue, 12 Oct 1999 15:51:43 -0500 (CDT)

```Maybe someone can help me understand this.

> There can be a difference between 1x1 matrices and scalars.
>
> Consider the matrix product A*B*C where
>
> A = [1 1]     B = [1]     C=[1]
> [1]       [2]
> [3]
>
> The product A*B*C is not defined because B*C is not defined.

(I don't know what the free-floating [1], [2] and [3] are, so I'll ignore
them even though I may be making an ass of myself.)

Why is B*C not defined?  Mathematically speaking, isn't the product of a
1x1 matrix times a 1x1 matrix also a 1x1 matrix?  If it isn't, it should
be!  :-)

Is there anything more to the problem than this:  MATLAB doesn't allow use
of a 1x1 matrix.  That is, MATLAB will redefine a 1x1 matrix as a scalar,
and the user has no control over that.

Mike

--
Michael B. Miller
University of Missouri--Columbia
http://taxa.psyc.missouri.edu/~mbmiller/

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