fulldiff.m

Symbolically computes full time derivative of given function and time dependant variables. It's an expansion of the partial derivative functionality of DIFF. Chain rule application automatically creates necessary higher order derivatives. Only base dependent variable need to be input, eg {x y}, dx and dy, etc. are assumed time dependant and d2x and d2y are created if required. This is motivated by the combination of partial derivative and full derivative required to compute Lagrange?s equations of motion.