revise readme

README.md

@@ -36,4 +36,7 @@ Open the file "filesread.m" and set all paths at the top of this file. The rest
 (4) Converting `.csv` files to NetCDF files:
 
 There is some files in utils directory in this repository. The utils are used to
-read `.csv` files and save them in `.nc` format.
+read `.csv` files and save them in `.nc` format. 
+
+> An example NetCDF file is stored in the project directory to show the desired
+  structure of variables in one file.