mus: add comment on truly incremental (fast) solvers for mus
@@ -25,6 +25,7 @@ def mus(soft, hard=[], solver="ortools"):
:param: soft: soft constraints, list of expressions
:param: hard: hard constraints, optional, list of expressions
:param: solver: name of a solver, see SolverLookup.solvernames()
+ "z3" and "gurobi" are incremental, "ortools" restarts the solver
"""
# order so that constraints with many variables are tried and removed first
candidates = sorted(soft, key=lambda c: -len(get_variables(c)))
