A valid state attribute should be either a character vector, a cell array or a valid MATLAB structure

please answer this question

[Adam]

You haven't asked a question.

[Guillaume]

And presuming that the question title is an error message (coming from what ?), what is the difficulty in understanding it? Check your state attribute (whatever that is) and make sure that it is either a character vector, a cell array, or a valid structure (as per the documentation of whatever function you're using).