diff --git a/Demo/DEMO_matplotlib.py b/Demo/DEMO_matplotlib.py
index 5803b5c..f2e31d7 100644
--- a/Demo/DEMO_matplotlib.py
+++ b/Demo/DEMO_matplotlib.py
@@ -1,3 +1,4 @@
+#program for matplotlib
 # import os
 import numpy as np
 import numpy.random as rd