How to use for loop to iterate over the elements of the initial matrix and keep just the ones in the diagonal.

Hey, I have a random 3x3 matrix and i need to create a new vector (size 1x3 or 3x1) storing the diagonal using a for loop (and potentially conditions) to iterate over the elements of the initial matrix and keep just the ones in the diagonal.

So bassically i need to get the main diagonal from matrix using for loop.

%Create a 3x3 array with random number from 1 to 100
R= randi([1,100],3,3)

I would appriciate any hints on how to solve it!

Thanks in advance!

Answer 1

[Torsten]

D =[R(1,1);R(2,2);R(3,3)]

or

D = zeros(3,1);
for i=1:3
    D(i) = R(i,i);
end

What's the problem ?

[Arina Kovalova]

Thank you! That worked just fine! There is no problem Im just new to mathlab)