How to break out of a while loop inside a function block ?

I'm trying to break out of a while loop when a key is pressed and I've achieved this through the following code snippet -

 keep = 1; 
 h = figure('KeyPressFcn','keep=0');
 while keep
  pause(0.01)
 end
 close(h)

I need to incorporate this into a GUI. But when this exact same code snippet is inserted into a function block, I'm no longer able to break out of the loop. Here's a code for the same -

 function calibrate()
 keep = 1;
 h = figure('KeyPressFcn','keep=0');
 while keep
  pause(0.01)
 end
 close(h)

How do I get this to work ?

Thanks !

[Muthu Annamalai]

Please use {} Code editor feature to make your code more readable to others.

Answer 1

[Jon]

The search function is your friend. See https://ch.mathworks.com/matlabcentral/newsreader/view_thread/315080 for someone with the same problem, and an explanation and solution.

[Prashanth Krishnan]

Thanks Jon! This worked like a dream.

[Camile van der Heijden]

Unfortunately, the newsreader link Jon referred to is no longer available. I would love to know what it said though. Does it involve using flag variables?

Answer 2

[Muthu Annamalai]

Changing your code to,

       keep = true;
       h = figure('KeyPressFcn',@() keep= ~keep ); 
       while keep 
          pause(0.01) 
          sprintf('keep = %d',keep);
       end 
       close(h)

may work. If this doesn't work, make keep an instance of a handle class.

[Prashanth Krishnan]

Sorry but it didn't work..