Update control/passivity.py

Mark-Yeatman · bnavigator · web-flow · commit cd7ec0fce4cc · 2022-06-13T14:56:35.000-05:00
Co-authored-by: Ben Greiner &lt;code@bnavigator.de&gt;
diff --git a/control/passivity.py b/control/passivity.py
@@ -24,7 +24,7 @@ def is_passive(sys):
     '''
     if cvx is None:
         print("cvxopt required for passivity module")
-        raise ModuleNotFoundError
+        raise ModuleNotFoundError("cvxopt required for passivity module")
 
     A = sys.A
     B = sys.B
