THERMOCALC is a thermodynamic calculation program (Powell & Holland 1988) that uses an internally-consistent thermodynamic dataset (Holland & Powell, 1998, 2011) to undertake thermobarometry and phase diagram calculations for metamorphic rocks. However, using thermocalc to create a diagram is quite laborious; each curve must be calculated by hand and the Schreinemaker’s analysis must be done manually. The curves must be built up one by one, and manually combined.
PyPSbuilder is developed with idea to make this tedious process much easier and more enjoyable while keeping the concept to force users really understand the Phase Rule, Schreinemaker’s analysis, and how variance changes across field boundaries.
You can see pyPSbuilder in action in following tutorial http://pypsbuilder.readthedocs.io/en/latest/tutorial.html.