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Topic: Special matrix multiplication
Replies: 18   Last Post: Mar 22, 2012 5:12 AM

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 Milos Milenkovic Posts: 189 Registered: 4/4/09
Special matrix multiplication
Posted: Feb 4, 2012 6:59 AM

Dear,
suppose that we have two matrices, where each element has three values like follows:

A=[(a1,b1,c1), (a2,b2,c2); (a3,b3,c3), (a4,b4,c4)]
B=[(d1,e1,f1), (d2,e2,f2); (d3,e3,f3), (d4,e4,f4)]

Now, I have to multiply these two matrices, and that is matrix C=A*B

C=[ c11=(a1,b1,c1)*(d1,e1,f1)+(a2,b2,c2)*(d3,e3,f3), c12=(a1,b1,c1)*(d2,e2,f2)+(a2,b2,c2)*(d4,e4,f4); c21=(a3,b3,c3)*(d1,e1,f1)+(a4,b4,c4)*(d3,e3,f3), c22=(a3,b3,c3)*(d2,e2,f2)+(a4,b4,c4)*(d4,e4,f4)]

where the most important here is the low for multiplying these three-value numbers is:

(ai,bi,ci)*(di,ei,fi) = (bi*di+ei*(ai-bi), bi*ei , ei*ci+bi(fi-ei))

Please, how to do this, I have a dozen of this matrices with 700x700 in dimension approximately.
Best,
Milos