Maybe I'm using cells incorrectly, but to test I am multiplying a 4x4 matrix / array with the 4x4 identity. It should return the original matrix / array. However, I get an error message that won't allow me to perform the operation.
"??? Undefined function or method 'mtimes' for input arguments of type 'cell'.
This is irritating.

I wanted to use this as a check for my homework but I can't. Is there anyway around this error?
Thanks!