How to use while loop in matrix?

Hello, i have this question:

A=zeros(5,8);

Let A(i,j) be the (i,j)th element of A, where i=1,2,,..5 and j=1,2,...8. Use a while loop to replace each element of A in the following way.

If i>j set A(i,j)=4*i-2j.

If i<=j set A(i,j)=i^2-3j.

For now i try this code to solve

B=zeros(5,8);
k=1;
l=1;
while not(l==9)
        if k>l
            B(k,l)=4*k-2*l;
        else
            B(k,l)=k^2-3*l;
        end
        l=l+1;
end
B

I get the result for only first row and I dont know how to make this calculations for the other rows with while func. I know how to do with for loop but I couldnt figure it out to do iteration in while func.

Thanks for helping. :)

Answer 1

[Ameer Hamza]

Here is a solution without for-loop

A = zeros(5,8);
[i, j] = ndgrid(1:size(A,1), 1:size(A,2));
A = (4*i-2*j).*(i>j) + (i.^2-3*j).*(i<=j);

Result

>> A
A =
    -2    -5    -8   -11   -14   -17   -20   -23
     6    -2    -5    -8   -11   -14   -17   -20
    10     8     0    -3    -6    -9   -12   -15
    14    12    10     4     1    -2    -5    -8
    18    16    14    12    10     7     4     1