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    <p>For an "infinite" loop that can still be easily stopped when a certain condition is met, you can set up your <a href="https://www.mathworks.com/help/matlab/ref/while.html" rel="nofollow noreferrer">while condition</a> to be a <a href="https://www.mathworks.com/help/matlab/logical-operations.html" rel="nofollow noreferrer">logical variable</a> (i.e. flag) that can be updated within your loop:</p> <pre><code>keepLooping = true; % A flag that starts as true while keepLooping % Read, process, and plot your data here keepLooping = ...; % Here you would update the value of keepLooping based % on some condition end </code></pre> <p>A while loop can also be terminated if a <a href="https://www.mathworks.com/help/matlab/ref/break.html" rel="nofollow noreferrer"><code>break</code></a> or <a href="https://www.mathworks.com/help/matlab/ref/return.html" rel="nofollow noreferrer"><code>return</code></a> command is encountered within the loop.</p> <p><br> <strong>EXAMPLE:</strong></p> <p>As an example of some of the GUI-based ways you can stop a loop, here is a program that creates a simple GUI that continuously increments and displays a counter once every second using a while loop. The GUI has two ways to stop the loop: a <a href="https://www.mathworks.com/help/matlab/ref/uicontrol.html" rel="nofollow noreferrer">push button</a> or pressing <kbd>q</kbd> while the figure window has focus (using the <a href="https://www.mathworks.com/help/matlab/ref/matlab.ui.figure-properties.html#property_d119e285730" rel="nofollow noreferrer"><code>'KeyPressFcn'</code> property</a> of the figure to run code when a key is pressed). Just save this code in an m-file somewhere on the MATLAB path and run it to test the example:</p> <pre><code>function stop_watch hFigure = figure('Position', [200 200 120 70], ... % Create a figure window 'MenuBar', 'none', ... 'KeyPressFcn', @stop_keypress); hText = uicontrol(hFigure, 'Style', 'text', ... % Create the counter text 'Position', [20 45 80 15], ... 'String', '0', ... 'HorizontalAlignment', 'center'); hButton = uicontrol(hFigure, 'Style', 'pushbutton', ... % Create the button 'Position', [20 10 80 25], ... 'String', 'Stop', ... 'HorizontalAlignment', 'center', ... 'Callback', @stop_button); counter = -1; keepLooping = true; while keepLooping % Loop while keepLooping is true counter = counter+1; % Increment counter set(hText, 'String', int2str(counter)); % Update the counter text pause(1); % Pause for 1 second end %---Begin nested functions--- function stop_keypress(hObject, eventData) if strcmp(eventData.Key, 'q') % If q key is pressed, set keepLooping = false; % keepLooping to false end end function stop_button(hObject, eventData) keepLooping = false; % Set keepLooping to false end end </code></pre> <p>The above example makes use of <a href="https://www.mathworks.com/help/matlab/matlab_prog/nested-functions.html" rel="nofollow noreferrer">nested functions</a> so that the <code>'KeyPressFcn'</code> and button callback can access and modify the value of <code>keepLooping</code> in the workspace of the <code>stop_watch</code> function.</p>
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    1. POHow can I loop indefinitely, but stop on some condition(s)?
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    1. POHow can I loop indefinitely, but stop on some condition(s)?
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    1. CONote that this won't work without the `pause` (without `pause` it will finish the loop and then process the queued-up callback events afterwards, defeating the purpose). Note that it's the `drawnow` command which actually processes the queues, and `pause` calls `drawnow` (or does the equivalent), so it's probably better to add a `drawnow` explicitly alongside `pause`, for readability reasons.
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    2. COI ran into this issue because I was using a more accurate way to wait, based on `java.lang.Thread.sleep(..)` or `Object.wait(..)` and `java.lang.Thread.yield()`, and that is different from `pause` because these methods do not include the collateral call to `drawnow` (or equivalent).
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