icinga2/lib/livestatus/stdaggregator.cpp

58 lines
2.3 KiB
C++

/******************************************************************************
* Icinga 2 *
* Copyright (C) 2012-2017 Icinga Development Team (https://www.icinga.com/) *
* *
* 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.hpp"
#include <math.h>
using namespace icinga;
StdAggregator::StdAggregator(const String& attr)
: m_StdAttr(attr)
{ }
StdAggregatorState *StdAggregator::EnsureState(AggregatorState **state)
{
if (!*state)
*state = new StdAggregatorState();
return static_cast<StdAggregatorState *>(*state);
}
void StdAggregator::Apply(const Table::Ptr& table, const Value& row, AggregatorState **state)
{
Column column = table->GetColumn(m_StdAttr);
Value value = column.ExtractValue(row);
StdAggregatorState *pstate = EnsureState(state);
pstate->StdSum += value;
pstate->StdQSum += pow(value, 2);
pstate->StdCount++;
}
double StdAggregator::GetResultAndFreeState(AggregatorState *state) const
{
StdAggregatorState *pstate = EnsureState(&state);
double result = sqrt((pstate->StdQSum - (1 / pstate->StdCount) * pow(pstate->StdSum, 2)) / (pstate->StdCount - 1));
delete pstate;
return result;
}