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How to do matrix or table multiplication?

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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3 Answers

Answer by Walter Roberson
on 6 Sep 2019
 Accepted Answer

resultTable = kron(IntakeTable,ones(1,size(ExhaustTable,2))) + repmat(ExhaustTable,1,size(IntakeTable,2));

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Answer by 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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Thank you@ Bjorn Gustavsson

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Answer by Adam Danz
on 6 Sep 2019
Edited by Adam Danz
on 6 Sep 2019

resultTable = repmat(ExhaustTable,1,3) + repelem(IntakeTable,1,3)
Or, if the number of columns vary,
resultTable = repmat(ExhaustTable,1,size(IntakeTable,2)) + repelem(IntakeTable,1,size(ExhaustTable,2))

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