MATLAB: While loop if condition

Question

Hello,

I have a while loop that I want to run if two conditions are met. I have the while loop and the first condition written out and its below.

A(1,k) = .35; %guess value for alpha^0
            
            epsi = .1; 
            sigma = 2;
            
            xad = X(:,k)+A(1,k)*D(:,k);
            
            left = fun(xad);
            
            right = fun(X(:,k))+ A(1,k)*epsi*grad_fun(X(:,k))'*D(:,k);
            
            A_2(1,j) = A(1,k); 
            
            while (left > right) || (
                
                A_2(1,j+1) = A_2(1,j)/(sigma);
                
                xad = X(:,k)+A_2(1,j+1)*D(:,k);
                
                left = fun(xad);
                
                right = F(1,k)+ (A_2(1,j+1)*epsi*D(:,k)')*D(:,k);
                
                j= j+1;
    
            end

However, I also want to add a condition for the while loop to run that if left is an imaginary number, to cycle through the loop.

Is this possible? Thank you

Answer 1

Hi Braden,

You can add these conditions in the while loop.

(~isreal(left)) % To check if left is a complex number
(imag(left) ~= 0) % If the check is only to ensure if there is an imaginary content, implies value could be complex
(imag(left) ~= 0 && real(left) == 0) % If the check is to ensure, it is only imaginary number

The usage of || or && depends on the condition, you wanted. If both the conditions to be met, then use &&. If either of conditions have to be met use ||.

Hope this helps.

Regards,

Sriram