MATLAB: How to write a loop in MATLAB that continues until the user presses any key

MATLABuntil

I want to run a specific routine in a loop. However I want the user to be able to exit the loop and end the routine by pressing any key on the keyboard.

Best Answer

MATLAB does not have a function that scans for keyboard activity without interrupting the event stream.
However, if your program involves a figure window, you can utilize the ‘KeyPressFcn’ property. The 'KeyPressFcn' is called when a key is pressed with an active figure window. You can set this function to change the state of a flag that ends a loop. Copy the following functions to a MATLAB file, and execute the MATLAB file.
function myLoopingFcn() 
global KEY_IS_PRESSED
KEY_IS_PRESSED = 0;
gcf
set(gcf, 'KeyPressFcn', @myKeyPressFcn)
while ~KEY_IS_PRESSED
      drawnow
      disp('looping...')
end
disp('loop ended')
function myKeyPressFcn(hObject, event)
global KEY_IS_PRESSED
KEY_IS_PRESSED  = 1;
disp('key is pressed')
The code will display "looping" in the MATLAB Command Window until a key is pressed when the figure window is active.
Related Question