Efficiently assigning class property in a quadruple loop?

Is there a better way to assign values to a very complicated object with multiple nested classes and properties? I have the following piece of code in a quadruple loop right now, but it is a serious bottleneck in my code. Is there a better way of handling something like this?

for ind_1 = 1:N1
    for ind_2 = 1:N2
        for ind_3 = 1:N3
            for ind_4 = 1:N4
                if any(myLogicalVector)
                    obj.prop(ind_1).interaction(ind_2,ind_3,ind_4).interaction_flag = someFixedValue1;
                else
                    obj.prop(ind_1).interaction(ind_2,ind_3,ind_4).interaction_flag = someFixedValue2; 
                end
            end
        end
    end
end

Answer 1

[Matt J]

You've not told us the dependence of myLogicalVector and someFixedValue* on the loop variables, which is probably super-important to know here. At minimum, though, this could be reduced to a double loop.

for i = 1:N1
    
    interaction=obj.prop(i).interaction;
    
    for j=1:N2*N3*N4

                if any(myLogicalVector)
                    interaction(j).interaction_flag = someFixedValue1;
                else
                    interaction(j).interaction_flag = someFixedValue2; 
                end

    end
    
   obj.prop(i).interaction=interaction;
end

[Matt J]

The best way to achieve performance gains would probably be to redesign the data structure itself. For example, I speculate that you do not need to have an N2xN3xN4 array of "interaction" property values. Instead, have "interaction" be a scalar property which holds an N2 x N3 x N4 array of interaction flags. If you can do that, the above could be reduced to,

for i = 1:N1
    

    
    obj.prop(i).interaction.interaction_flag(logicalIndex)=someFixedValue1;
    
    obj.prop(i).interaction.interaction_flag(~logicalIndex)=someFixedValue2;

end