Merge remote-tracking branch 'lbianchi-lbl/multi-scip-testing' into m…

…ulti-scip-testing

idaes/core/util/tests/test_model_diagnostics.py

@@ -2002,23 +2002,32 @@ def test_solve_candidates_milp(self, model, scip_solver):
         dh._prepare_candidates_milp()
         dh._solve_candidates_milp()
 
+        assert dh.degenerate_set == {
+            model.con2: value(dh.candidates_milp.nu[0]),
+            model.con5: value(dh.candidates_milp.nu[1]),
+        }
+
         assert abs(value(dh.candidates_milp.nu[0])) == pytest.approx(1e-05, rel=1e-5)
         assert abs(value(dh.candidates_milp.nu[1])) == pytest.approx(1e-05, rel=1e-5)
 
-        assert value(dh.candidates_milp.y_pos[0]) == pytest.approx(0, abs=1e-5)
-        assert value(dh.candidates_milp.y_pos[1]) == pytest.approx(0, rel=1e-5)
+        # One must be positive and one must be negative, so produce will be negative
+        assert value(
+            dh.candidates_milp.nu[0] * dh.candidates_milp.nu[1]
+        ) == pytest.approx(-1e-10, rel=1e-5)
 
-        assert value(dh.candidates_milp.y_neg[0]) == pytest.approx(0, abs=1e-5)
-        assert value(dh.candidates_milp.y_neg[1]) == pytest.approx(1, abs=1e-5)
+        assert (
+            value(
+                dh.candidates_milp.y_pos[0]
+                + dh.candidates_milp.y_pos[1]
+                + dh.candidates_milp.y_neg[0]
+                + dh.candidates_milp.y_neg[1]
+            )
+            >= 1
+        )
 
         assert value(dh.candidates_milp.abs_nu[0]) == pytest.approx(1e-05, rel=1e-5)
         assert value(dh.candidates_milp.abs_nu[1]) == pytest.approx(1e-05, rel=1e-5)
 
-        assert dh.degenerate_set == {
-            model.con2: value(dh.candidates_milp.nu[0]),
-            model.con5: value(dh.candidates_milp.nu[1]),
-        }
-
     @pytest.mark.unit
     def test_prepare_ids_milp(self, model):
         dh = DegeneracyHunter2(model)