How can I call a function every three time steps?

I want to call my function every three time steps.

So, at tt = 3,6,9,12,...,tmax I want to call [G] = myfunction(r, Gamma); inside the if statement. And at tt = 1,2,4,5,7,8,... the if statement should be executed but without calling the function.

for tt = 1:tmax
    if
        ...
    end
end

I would appreciate your thoughts and ideas.

Thanks

Answer 1

[DGM]

Something like this:

for tt=1:20
	if ~mod(tt,3)
		% do special stuff in this case
		disp('tt is a multiple of 3')
	end
	
	% do normal stuff every time
end

[Asaf McRock]

Thank you so much.