How to do matrix or table multiplication?
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    raghavendra kandukuri
 on 6 Sep 2019
  
    
    
    
    
    Commented: raghavendra kandukuri
 on 6 Sep 2019
            Hi,
I have this two tables or matrix, where i am looking to perform the addition of 1st element in the first matrix of first row with the all element in the first row of second matrix and similarly with the second element in the first matrix of first row with the all the elements of first row in second matrix. Similarly with the second and third row elements.
Is there any easy way or formula to do this? even if the size of the matrix changes
Example:
IntakeTable =  [0 3 2 
                4 2 2 
                4 4 4 ];
ExhaustTable = [0 3 2 
                4 2 2 
                2 2 2 ];
 resultTable =[0+0 0+3 0+2 3+0 3+3 3+2 2+0 2+3 2+2
               4+4 4+2 4+2 2+4 2+2 2+2 2+4 2+2 2+2
               4+2 4+2 4+2 4+2 4+2 4+2 4+2 4+2 4+2]               
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Accepted Answer
  Walter Roberson
      
      
 on 6 Sep 2019
        resultTable = kron(IntakeTable,ones(1,size(ExhaustTable,2))) + repmat(ExhaustTable,1,size(IntakeTable,2));
More Answers (2)
  Bjorn Gustavsson
      
 on 6 Sep 2019
        Looping seems simplest and most easily readable for humans:
szI = size(IntakeTable);
szE = size(ExhaustTable);
resultTable = zeros(size(ExhaustTable,1),size(ExhaustTable,2)*size(IntakeTable))
for i1 = 1:szI(2),
  resultTable(:,(1:szE,2)+(i1-1)*szE(2)) = repmat(IntakeTable(:,i1),1,szE(2)) + ...
      ExhaustTable;
end
HTH
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