Check out example codes for "matlab matrix index". It will help you in understanding the concepts better.
Code Example 1
A = [16 5 9; 4 2 11; 7 14 9]; % Create matrix
A(2,3) % Extract the element in row 2, column 3
ans = 11
A(1:2,2:3) % Extract elements in rows 1 and 2, and columns 2 and 3
ans = 5 9
2 11
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