Hi Jason,
You should be able to use the example 'Train Multiclass Linear Classification Model' on the documentation page for "fitcecoc": https://www.mathworks.com/help/stats/fitcecoc.html
This example uses categoricals, which by default are nominal, as input to "fitcecoc". See more about categoricals at the documentation page: http://www.mathworks.com/help/matlab/ref/categorical.html
You shouldn't need to set 'Coding' to achieve nominal classification.
Good luck!
