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Re: [Outer [Times, , ] ] Question

  • To: mathgroup at smc.vnet.net
  • Subject: [mg45855] Re: [Outer [Times, , ] ] Question
  • From: Mariusz Jankowski<mjankowski at usm.maine.edu>
  • Date: Tue, 27 Jan 2004 04:51:01 -0500 (EST)
  • Organization: University of Southern Maine
  • References: <bv00aa$jda$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

Remove MatrixForm from your lines m1 = ..., m2 = ... etc

Mariusz




>>> <MichaelSMcCain at cs.com> 1/25/2004 3:55:38 AM >>>
Hi:

I want to take a Column Vector and multiply it by a Row Vector to create an

"Outer" Matrix. 

In other words, I want to take a 5x1 Column Vector and multiply it by a 1x4

Row Vector and output a 5x4 Matrix.

I then want to add several of these Matrices together and obtain a "final" 
Matrix.

I tried the following:

x1 = {1, -1, -1, 1, 1};
y1 = {1, 1, -1, -1};

x2 = {-1, 1, -1, 1, -1};
y2 = {1, -1, 1, -1};

x3 = {1, 1, -1, -1, 1};
y3 = {-1, -1, 1, 1};

m1 = MatrixForm[Outer [Times, x1, y1] ]
m2 = MatrixForm[Outer [Times, x2, y2] ]
m3 = MatrixForm[Outer [Times, x3, y3] ]

mm = m1 + m2 + m3

MatrixForm[mm]

The output that I get is incorrect and does not combine into a single
Matrix.


What am I doing wrong?

Thanks,


Mike McCain
MichaelSMcCain at cs.com 




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