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Subject: Re: usage of " . " in these two equations !!!
Date: Wed, 18 Feb 2009 03:43:02 +0000 (UTC)
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"Kuo-Hsien" <mchangks@hotmail.com> wrote in message 
> What is the difference between these two equations? Why do we need to put a " . " behind numbers? Can you guys help me to under this usage?


The dot is read as 'element-by-element' when used like this.  Study an easy example if it is still unclear to you.

A = magic(2)
A^2
A*A
A.^2

Now, which one to use in your application will depend on what you are trying to do.




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