MATLAB: Why do I have an error on the length function

Question

hi, I have a file of 70080 lines of which I want to obtain the autocorrelation graph, why do I get this error? I state that previously it worked, can anyone help me?

Also, can anyone give me clues as to what autocorrelation indicates? what is it for?

Answer 1

You do not have an error on the length function. You have an error on the lenght function.

length  <- what you want
lenght  <- what you have