From 4bc5fb5783ffccdfadced01a31a548978fada9ec Mon Sep 17 00:00:00 2001
From: Jake Lishman <jake.lishman@ibm.com>
Date: Thu, 11 Nov 2021 21:43:10 +0000
Subject: [PATCH] Fix ZeroDivisionError in qiskit_backend_overview (#7260)

---
 qiskit/tools/jupyter/backend_overview.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/qiskit/tools/jupyter/backend_overview.py b/qiskit/tools/jupyter/backend_overview.py
index 876b9fc9a5c3..33053c35ed65 100644
--- a/qiskit/tools/jupyter/backend_overview.py
+++ b/qiskit/tools/jupyter/backend_overview.py
@@ -199,7 +199,8 @@ def backend_widget(backend):
                         if param["value"] != 1.0:
                             sum_cx_err += param["value"]
                             num_cx += 1
-        avg_cx_err = round(sum_cx_err / (num_cx), 4)
+        if num_cx > 0:
+            avg_cx_err = round(sum_cx_err / num_cx, 4)
 
     cx_widget = widgets.HTML(value=f"<h5>{avg_cx_err}</h5>", layout=widgets.Layout())