Swiss Original. Mirrors: DE, US, IE, TW



This module holds a collection of functions for doing advanced calculations and effects on rrd files.



Pull the data values off the rrd file and calculate the standard deviation. Nan values get ignored in this process.


Copyright 2007 by Tobias Oetiker


This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.


Tobias Oetiker <>

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