MATLAB: Matrix Multiplication, row by row multiplication and column by column multiplication

matrix multiplication

Hi there,
I was wondering what matlab function I can use to multiply a matrix by another matrix and then multiply those two matrices row by row and then column by column. Yielding a total of three matrix multiplications: regular matrix multiplication, row by row multiplication, and column by column multiplication.
 Code
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A = ([ 1 2 3; 4 5 6; 7 8 9]); 
B = ([ 2 2 2; 2 2 2 ; 2 2 2]);
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...For example...
Regular matrix multiplication: A*B = ([12 12 12; 30 30 30; 48 48 48])
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How can I write it to multiply the matrix row by row and column by column?
Row by row multiplication: RowsA*RowsB = ([12 12 12; 30 30 30; 48 48 48])
Column by column multiplication: ColsA*ColsB = ([12 12 12; 30 30 30; 48 48 48])
Thank you.

Best Answer

There is no in-built function but you can do this:
A = [ 1 2 3; 4 5 6; 7 8 9] 
B = [ 2 2 2; 2 2 2 ; 2 2 2]
A*B %regular matrix multiplication
A.*B %element wise matrix multiplication
[m,n]=size(A)
for i = 1:m
rows(i,:)=A(i,:).*B(i,:) %multiplies rows
end
for i=1:n
    columns(:,i)=A(:,i).*B(:,i) % multiplies columns
end
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