how sum all element which are the right of diagonal. where row=colom .....i have done this much but confuse in further operation

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Abdur Rob 2020-9-26

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评论： Abdur Rob 2020-9-26

function summa = halfsum(A)
    %A = randi(n,x,y);
    [row,col] = size(A);
    
    if row == col
        for r = 1:row
            for c = 1:col
                summa = sum(A(r,c)) + sum(A(r,c));
            end
        end
    else
        fprintf('Input correct matrix.\n')
    end
end

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Image Analyst 2020-9-26

Is this homework (sounds a lot like it)? If so, tag as homework. In the meantime, check out triu() and tril(), and consider if r <= or >= c

if c >= r    % or....
if c <= r   

if you want/need to do it as a for loop.

Abdur Rob 2020-9-26

not really ,, actually i'm learning MATLAB and i found this problem from web that's why i need help

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KSSV 2020-9-26

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编辑：KSSV 2020-9-26

Read about triu.

https://in.mathworks.com/help/matlab/ref/triu.html

If A is your matrix, use:

iwant = sum(sum(triu(A)))

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KSSV 2020-9-26

Read the documentation..it is clear in the documentation.

Also you can use loops like below:

A = rand(3) ;
[m,n] = size(A) ; 
upper_diagonal = zeros([],1) ; 
count = 0 ;
for i = 1:m
  for j = 1:n
    if i<=j
      count = count+1 ; 
      upper_diagonal(count) = A(i,j) ; 
    end
  end
end