A model-tracing ITS is a system where students can enter full solutions of multi-step problems like it is shown here (this is a screenshot of Andes Physics Tutor, probably the most advanced model-tracing ITS):
Users of model-tracing ITS can check their solution steps for correctness, receive hints, receive grades for their solutions - all of that is done automatically.
This repository contains Andes Physics Tutor algorithm of dependency checking. I realized it as it was described in [1] to examine its properties.
1 - J.A.Shapiro. An Algebra Subsystem for Diagnosing Students' Input in a Physics Tutoring System
This repository requires SymPy v.0.7.2 (it won't work with SymPy 0.7.3 cause it has a different realization of matrices) Works with Python 2.7 and numpy 1.6.1