If the error you receive is that 'origin' is not a valid or recognized value for the XAxisLocation property, you may be using a release older than release R2015b which is when that value was added as an option for the XAxisLocation property. The alternative for earlier releases is to use PlotAxisAtOrigin.
Note that the labels of the last tick marks disappear when setting the axes location to the origin using
ax.XAxisLocation = 'origin'; ax.YAxisLocation = 'origin';
For a discussion on this problem refer to here. I have yet to find a solution to this problem that will respect axes labeling of font size from a main program such as
set(ax,'FontSize',20);
You can manually insert the tick labels using the text() function but they will not change using the above command. I would prefer MathWorks change the 'origin' feature to respect the same tick labeling as appears when using 'bottom' or 'top'.
