From: Jonathon <rayomia@gmail.com>
To: Teacher2Teacher Public Discussion
Date: 2006030818:59:07
Subject: Difference between a number and matrix

	
What is the difference between a 1x1 matrix and a number.

Why when you multiply a constant by a matirx the dimensions are
irrelevant

5*[1,1,1:1,1,1:1,1,1] = [5,5,5;5,5,5;5,5,5]

but if you cannot multiply a 1x1 by anything that does not contain
either a row or a column of 1.

ex

[5] * [1,1,1;1,1,1;1,1,1] violates matrix multiplication rules

5*eye*[1,1,1;1,1,1;1,1,1]= [5,5,5;5,5,5;5,5,5]

what is the diffence
between 
5 and [5]?

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