(Originally posted on Doug's MATLAB Video Tutorials blog.)

If you push a button in a MATLAB UI and this starts a long calculation, what do you want to have happen if the user pushes the button a second time? Interuptable property and BusyAction property of a UICONTROL dictate the behavior. This video shows the different interactions and also shows a nice technique for seeing the results. A persistent value in MATLAB is used to keep count between runs.