I noticed that new versions of MATLAB change functionality of previous versions, so that my old programs do not work with new versions! It is very bad. It means that old text books are not true anymore. Few examples: 1. The command diff('sin(x)') returned 'cos(x)' in the past, before v. 2014. 2. The v. 2017 is, again, different. It says "EZPLOT is not recommended. Use FPLOT or FIMPLICID instead"
I am sure that MathWorks should be responsible for its previous versions!