MATLAB Grader does not have a built-in way to check properties of a plot. This is partly because comparing strings is especially error prone (spaces, capitalization, spelling, extra info like units included or not, etc). The "Function or Keyword is Present" test only checks that the listed functions/keywords were used in the solution. It does not check their values or settings.
Our recommendation would be first evaluate the necessity of such assessment tests. If they are deemed necessary, we would recommend using the "Function or Keyword is Present" assessment test to check that the functions 'title', 'xlabel', and 'ylabel' were used in the learner solution rather than checking the actual values. You can see an example in the following sample problems:
- Introduction to Programming > Graphing > Projectile trajectory (plot of multiple data series)
- Introduction to Programming > Graphing > Plot a decaying cosine wave (basic plot of mathematical function)