how can i prelocate arrays

[James Tursa]

Please edit your question and post your code as text formatted with the CODE button. We cannot copy & paste pictures into MATLAB to try out your code. My guess is that u is a variable and not a function, so using t(i) in the indexing may be the cause of the problem.

[John D'Errico]

Yes. I think you are correct. The obvious problem is if u is a variable, are the terms like (u(t(i) + pi)). t(i) + pi will never be an exact integer.

Answer 1

[SaiDileep Kola]

Pre allocating arrays may not solve your problem, as the error msg states you are indexing array ”u” using either negative integers or fractions, check if “t(i)-3” value turns out to be a negative or fraction.