Question

Write your own matlab code to perform matrix multiplication. Recall that to multiply two matrices, the inner dimensions must be the same. Write this as a function with input arguments the matrices to be multiplied and output argument the resultant matrix, use "assert" statement(s) to check that the input arguments are valid and print an error message if they are not. Test with A=[1,2,3;4,5,6] and B=[7,8;9,10;11,12] showing results for: (a) A*B, (b) B*A, and (c) A*A.

Answer 1

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clc
function mul=matrix_mul(A,B)
row_A=size(A,1);
col_A=size(A,2);
row_B=size(B,1);
col_B=size(B,2);
assert(col_A==row_B,'Not Valid Argument.') %assetion
mul=zeros(row_A,col_B);
for i=1:row_A
for j=1:col_B
for k=1:col_A
mul(i,j) = mul(i,j)+ A(i,k) * B(k,j);
end
end
end
  
end

A=[1,2,3;4,5,6];
B=[7,8;9,10;11,12];
result_AB=matrix_mul(A,B) %function result A*B
matlab_result_AB=A*B %matlab result A*B

result_BA=matrix_mul(B,A)
matlab_result_BA=B*A

result_AA=matrix_mul(A,A)

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