App Designer - Adding two variables halts process

I have a timer which ticks every 0.5s. It calls a function which adds two numbers, the sum of which is assigned to one of those numbers.

E.g.

x = x + y;

For some reason however, nothing will run after this line. Nothing. It just stops. I get rid of this and everything below works fine. What is going on?

I have a function that is supposed to be called after this line which never gets called if I have this addition above it. I remove the addition, the function then calls. I need the addition but having it just breaks it.

[Geoff Hayes]

@Byron Piper - can you show us the callback function and the code that is called? Are you sure there are no errors in the console window? Are x and y just floating-point variables or are they some other data type?

Answer 1

[Abhishek Chakram]

Hi Byron Piper,

It is my understanding that you are facing difficulty setting up a timer and it’s callback in the App Designer. Here is a sample code for the same:

% Initialize variables
x = 5; % Initial value of x
y = 3; % Initial value of y

% Create and start the timer
t = timer('ExecutionMode', 'fixedRate', 'Period', 0.5, 'TimerFcn', @timerCallback);
start(t);

% Timer callback function
function timerCallback(~, ~)
    % Add y to x and assign the sum back to x
    x = x + y;

    % Call a function after the addition
    myFunction(x);
end

% Function called after the addition
function myFunction(value)
    disp(['The value after addition is: ' num2str(value)]);
end

in this example a timer is created which executes a callback ‘timerCallback‘ that updates the value of x. You can add this [AJ1] to code to any buttonPushedCallback or startupFcn callback.

Best Regards,

Abhishek Chakram