Use TIMER to call a function

I have a function called watch which accepts clock() as input. I would like this function to run every second, so I created a timer sec to call that function

function watch(time)
disp(time)
end

sec = timer;
set(sec,'ExecutionMode','fixedRate','TimerFcn',{@watch,clock()});
start(sec)

But the code produces the following error:

Error while evaluating TimerFcn for timer 'timer-14' 
Too many input arguments.

What is the correct way of calling the watch function? Using R2017b

Thanks.

Answer 1

[Walter Roberson]

function watch(~, ~, time)

Note that this will always give you the same time. When you create a callback such as [@watch,clock()} then those arguments are evaluated at the time the callback is constructed, so the time of callback construction is what is going to be recorded in the callback.

You should consider,

sec = timer;
set(sec,'ExecutionMode', 'fixedRate', 'TimerFcn', @(varargin) disp(datetime()));
start(sec)