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Matrix Dot Product

  • To: mathgroup at smc.vnet.net
  • Subject: [mg52159] Matrix Dot Product
  • From: "MacDonald, Calum \(MAT\)" <C.A.MacDonald at gcal.ac.uk>
  • Date: Sat, 13 Nov 2004 04:40:07 -0500 (EST)
  • Sender: owner-wri-mathgroup at wolfram.com

Hi

I was wondering if someone could please help me with a command for
calculating the dot product of two (NxN) matrices. 

For example, for  two (2x2) matrices, A and B, we define the dot product
as:

A(1,1)*B(1,1) + A(2,1)*B(2,1) + A(1,2)*B(1,2) + A(2,2)*B(2,2)

i.e. we multiply corresponding entries of the matrices and sum these
values.

It is easy to write this in a loop but for large matrices the
calculation is rather slow.

Is there a Mathematica function that I can call that will allow me to do
this faster?

Thanks

Calum




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