icinga2/components/livestatus/stdaggregator.cpp

46 lines
2.0 KiB
C++

/******************************************************************************
* Icinga 2 *
* Copyright (C) 2012-2013 Icinga Development Team (http://www.icinga.org/) *
* *
* 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. *
******************************************************************************/
#include "livestatus/stdaggregator.h"
#include <math.h>
using namespace livestatus;
StdAggregator::StdAggregator(const String& attr)
: m_StdSum(0), m_StdQSum(0), m_StdCount(0)
{
m_StdAttr = attr;
}
void StdAggregator::Apply(const Table::Ptr& table, const Value& row)
{
Column column = table->GetColumn(m_StdAttr);
Value value = column.ExtractValue(row);
m_StdSum += value;
m_StdQSum += pow(value, 2);
m_StdCount++;
}
double StdAggregator::GetResult(void) const
{
return sqrt((m_StdQSum - (1 / m_StdCount) * pow(m_StdSum, 2)) / (m_StdCount - 1));
}