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Subject: Re: if d = x^2, and x=[0,0;1,0] then why is eval(d) not equal to
Date: Sat, 27 Mar 2010 23:54:06 +0000 (UTC)
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Don Robison <joe_blow_281@hotmail.com> wrote in message <1396842502.455793.1269723085870.JavaMail.root@gallium.mathforum.org>...
> Hello us.  This is Don Robison.  Thank you for your help, but the code does not return x^2.  I need to evaluate a symbolic expression such as x^i*y^i*z^k, and have the matrix multiplied by itself i,j,k times.  The code you gave seems to just return xd without taking it to the second power.
> 
> the input must be a trinomial with any power, the output must be that a sum of matrices that have been multiplied by themselves as many times as the exponent in the term.
> 
> the output I am looking for in this particular instance would be [0,0;0,0] or xd^2.

  Actually [0,0;0,0] is the correct answer!  The matrix product of that matrix by itself is all zeros.

Roger Stafford