Hello.I need to execute some matlab files on mathematica Online version...please assist me
On a computer, you can call MATLAB from Mathematica using MATLink
http://matlink.org/
but that isn't going to help for Mathematica online.
Indeed, and it requires MATLAB installed.
I'm afraid this isn't possible in the Wolfram Programming Cloud/Mathematica Online, since Mathematica and MATLAB are two incompatible systems.