Matlab -> variable name update inside a function

Question

Does anyone know how to update the name of variable "X" in a function?

For instance I have X[i] and I want to obtain X[i+1]. How do I firstly declare the initial variable and how do I update the name of it (in this case the index).

Edit 1: Better explanation.

I have some computation as output in the form of different size arrays. I want to name the matrix as depending on an index, for instance: array[i]=output(corresponding to the i index) array[j]=output(corresponding to the j index)

So, basically, I want to assign index dependent names to some variables but not manually.

Thanks!