Another grammar in doc string fix.

Mark · Mark · commit c57b928528df · 2022-06-13T17:08:48.000-05:00
diff --git a/control/passivity.py b/control/passivity.py
@@ -13,7 +13,7 @@
 
 def is_passive(sys):
     '''
-    Indicates if a linear time invarient system is passive
+    Indicates if a linear time invariant system is passive
 
     Constructs a linear matrix inequality and a feasibility optimization
     such that if a solution exists, the system is passive.
