From c1f18689af280918800463873ec3eee9607d2c95 Mon Sep 17 00:00:00 2001
From: Hang Yu <hyu12@tesla.com>
Date: Mon, 3 Oct 2022 13:47:29 -0700
Subject: [PATCH] Move sys._update_params(params) ahead of TimeResponseData
 return when ntates==0

---
 control/iosys.py | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/control/iosys.py b/control/iosys.py
index ce717c0fb..437c73d09 100644
--- a/control/iosys.py
+++ b/control/iosys.py
@@ -1779,6 +1779,9 @@ def input_output_response(
     else:
         noutputs = sys.noutputs
 
+    # Update the parameter values
+    sys._update_params(params)
+    
     #
     # Define a function to evaluate the input at an arbitrary time
     #
@@ -1816,9 +1819,6 @@ def ufun(t):
             output_labels=sys.output_index, input_labels=sys.input_index,
             transpose=transpose, return_x=return_x, squeeze=squeeze)
 
-    # Update the parameter values
-    sys._update_params(params)
-
     # Create a lambda function for the right hand side
     def ivp_rhs(t, x):
         return sys._rhs(t, x, ufun(t))