How do I create a game update in a while loop

I have this project for class to make a game and for this game I wanted to add an update feature where every 1/30 seconds it completes a "tick." Basically running a while loop where it starts a timer at the begining, runs some functions, and then waits for the timer to hit 1/30 seconds before looping again to keep the game smooth. I've looked into the timer function but haven't been able to get it to work and I was hoping for some help.

Answer 1

[Steven Lord]

numPasses = 0;
expectedDuration = seconds(1/30);
while numPasses < 5
dt = datetime('now');
n = 0;
while datetime('now')-dt < expectedDuration
    drawnow
    n = n + 1;
end
elapsed = datetime('now')-dt;
numPasses = numPasses + 1;
fprintf("Ended pass %d after 1/%1.6g seconds and %d executions of the loop body.\n", ...
    numPasses, 1./seconds(elapsed), n)
fprintf("\tExpected time: %1.6g s\n\t  Actual time: %1.6g s.\n", ...
    seconds(expectedDuration), seconds(elapsed))
end

Ended pass 1 after 1/29.873 seconds and 484 executions of the loop body.

	Expected time: 0.0333333 s
	  Actual time: 0.033475 s.

Ended pass 2 after 1/29.8739 seconds and 980 executions of the loop body.

	Expected time: 0.0333333 s
	  Actual time: 0.033474 s.

Ended pass 3 after 1/29.873 seconds and 1033 executions of the loop body.

	Expected time: 0.0333333 s
	  Actual time: 0.033475 s.

Ended pass 4 after 1/29.8134 seconds and 804 executions of the loop body.

	Expected time: 0.0333333 s
	  Actual time: 0.033542 s.

Ended pass 5 after 1/29.7336 seconds and 1047 executions of the loop body.

	Expected time: 0.0333333 s
	  Actual time: 0.033632 s.

There is a bit of overhead from the datetime call in the while loop condition that may make this technique unsuitable for your (fairly quick) 1/30 second loop, but the expected versus actual times look pretty close.