Merge pull request #843 from arcondello/feature/add-CQM-to-file-load

Load CQMs saved as files with load(..) function

dimod/constrained.py

@@ -394,3 +394,7 @@ def to_file(self, *, spool_size: int = int(1e9)) -> tempfile.SpooledTemporaryFil
 
 
 CQM = ConstrainedQuadraticModel
+
+
+# register fileview loader
+load.register(CQM_MAGIC_PREFIX, ConstrainedQuadraticModel.from_file)

tests/test_serialization_fileview.py

@@ -180,6 +180,22 @@ def test_bqm(self):
         bqm = BinaryQuadraticModel({'a': -1}, {'ab': 1}, 7, 'SPIN')
         self.assertEqual(bqm, load(bqm.to_file()))
 
+    def test_cqm(self):
+        cqm = dimod.CQM()
+
+        bqm = BinaryQuadraticModel({'a': -1}, {'ab': 1}, 1.5, 'SPIN')
+        cqm.add_constraint(bqm, '<=')
+        cqm.add_constraint(bqm, '>=')  # add it again
+
+        new = load(cqm.to_file())
+
+        self.assertEqual(cqm.objective, new.objective)
+        self.assertEqual(set(cqm.constraints), set(new.constraints))
+        for label, constraint in cqm.constraints.items():
+            self.assertEqual(constraint.lhs, new.constraints[label].lhs)
+            self.assertEqual(constraint.rhs, new.constraints[label].rhs)
+            self.assertEqual(constraint.sense, new.constraints[label].sense)
+
     def test_dqm(self):
         dqm = dimod.DiscreteQuadraticModel()
         dqm.add_variable(5, 'a')