We fetch the open file count by reading the values present in the file '/proc/sys/fs/file-nr'
We do not show a decimal value, unless the values returned have one. To avoid this, please edit the plugin script file as the following:
Open the plugin file and replace the line data["open_files"] = open_files to data["open_files"] = int(open_files)
Let us know for other queries, if any.