1 files changed, 37 insertions, 0 deletions
diff --git a/sumofsquares/mixins/sosexprmixin.py b/sumofsquares/mixins/sosexprmixin.py
new file mode 100644
index 0000000..d0c0d17
--- /dev/null
+++ b/sumofsquares/mixins/sosexprmixin.py
@@ -0,0 +1,37 @@
+import abc
+import polymatrix
+
+from sumofsquares.sosconstraint.abc import SOSConstraint
+from sumofsquares.sosconstraint.initsosconstraint import init_sos_constraint
+from sumofsquares.mixins.getsosconstraintmixin import GetSOSConstraintMixin
+from sumofsquares.sosexprbase.abc import SOSExprBase
+
+
+class SOSExprMixin(GetSOSConstraintMixin, abc.ABC):
+    @property
+    @abc.abstractmethod
+    def underlying(self) -> SOSExprBase:
+        ...
+
+    @property
+    def expr(self) -> polymatrix.Expression:
+        return self.underlying.expr
+
+    @property
+    def variables(self) -> polymatrix.Expression:
+        return self.underlying.variables
+
+    @property
+    def dependence(self) -> polymatrix.Expression:
+        return self.underlying.dependence
+
+    @property
+    def sos_matrix(self) -> polymatrix.Expression:
+        return self.underlying.sos_matrix
+
+    @property
+    def sos_constraints(self) -> tuple[SOSConstraint]:
+        return (init_sos_constraint(
+            dependence=self.dependence,
+            constraint=self.underlying.sos_matrix_as_vector,
+        ),)