To resolve issues starting MATLAB on Mac OS X 10.10 (Yosemite) visit: http://www.mathworks.com/matlabcentral/answers/159016
how to integrate arduino with MATLAB? which one is easier to integrate? Simulink or code?
This page has information about what packages you need in MATLAB/Simulink for Arduino support in current/previous releases. I don't know a lot about the differences, but I think if you simply want to interface with the Arduino, you can use the MATLAB package, but if you want to implement an algorithm that you want to download onto the Arduino, Simulink is better.