Given a finitely presented graded commutative differential algebra (GCDA), we
present a method to compute its minimal model up to a specified degree, together
with a map that is a quasi-isomorphism up to the given degree. The method works
by adding generators one by one. It terminates if and only if the minimal model is
finitely generated up to the given degree. A specific implementation of the method is
given.
The method allows us to develop and implement two criteria for
-formality, one
necessary and one sufficient. These criteria can be checked effectively, and have been able to determine
the
-formality
for every example that we have tested.