modifying the FME post-processing objective without creating and dele…

…ting it every iteration
emma58 · Dec 2, 2024 · 45691f7 · 45691f7
1 parent 518b161
commit 45691f7
Showing 1 changed file with 4 additions and 7 deletions.
diff --git a/pyomo/contrib/fme/fourier_motzkin_elimination.py b/pyomo/contrib/fme/fourier_motzkin_elimination.py
@@ -730,12 +730,9 @@ def post_process_fme_constraints(
                 continue
             # deactivate the constraint
             projected_constraints[i].deactivate()
-            m.del_component(obj)
-            # make objective to maximize its infeasibility
-            obj = Objective(
-                expr=projected_constraints[i].body - projected_constraints[i].lower
-            )
-            m.add_component(obj_name, obj)
+            # Our constraint looks like: 0 <= a^Tx - b, so make objective to
+            # maximize its infeasibility
+            obj.expr = projected_constraints[i].body - projected_constraints[i].lower
             results = solver_factory.solve(m)
             if results.solver.termination_condition == TerminationCondition.unbounded:
                 obj_val = -float('inf')
@@ -753,13 +750,13 @@ def post_process_fme_constraints(
                 obj_val = value(obj)
             # if we couldn't make it infeasible, it's useless
             if obj_val >= tolerance:
-                m.del_component(projected_constraints[i])
                 del projected_constraints[i]
             else:
                 projected_constraints[i].activate()
 
         # clean up
         m.del_component(obj)
+        del obj
         for obj in active_objs:
             obj.activate()
         # undo relax integrality