/*
    httperf -- a tool for measuring web server performance
    Copyright (C) 2000  Hewlett-Packard Company
    Contributed by David Mosberger-Tang <davidm@hpl.hp.com>

    This file is part of httperf, a web server performance measurment
    tool.

    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., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA
*/

#ifndef stats_h
#define stats_h

#include <math.h>

#define SQUARE(f)	((f)*(f))
#define VAR(s,s2,n)	(((n) < 2) ? 0.0 : ((s2) - SQUARE(s)/(n)) / ((n) - 1))
#define STDDEV(s,s2,n)	(((n) < 2) ? 0.0 : sqrt (VAR ((s), (s2), (n))))

#endif /* stats_h */