granicus.if.org Git - icinga2/blob - lib/livestatus/stdaggregator.cpp

   1 /******************************************************************************
   2  * Icinga 2                                                                   *
   3  * Copyright (C) 2012-2018 Icinga Development Team (https://www.icinga.com/)  *
   4  *                                                                            *
   5  * This program is free software; you can redistribute it and/or              *
   6  * modify it under the terms of the GNU General Public License                *
   7  * as published by the Free Software Foundation; either version 2             *
   8  * of the License, or (at your option) any later version.                     *
   9  *                                                                            *
  10  * This program is distributed in the hope that it will be useful,            *
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  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the              *
  13  * GNU General Public License for more details.                               *
  14  *                                                                            *
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  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.             *
  18  ******************************************************************************/
  19
  20 #include "livestatus/stdaggregator.hpp"
  21 #include <math.h>
  22
  23 using namespace icinga;
  24
  25 StdAggregator::StdAggregator(String attr)
  26         : m_StdAttr(std::move(attr))
  27 { }
  28
  29 StdAggregatorState *StdAggregator::EnsureState(AggregatorState **state)
  30 {
  31         if (!*state)
  32                 *state = new StdAggregatorState();
  33
  34         return static_cast<StdAggregatorState *>(*state);
  35 }
  36
  37 void StdAggregator::Apply(const Table::Ptr& table, const Value& row, AggregatorState **state)
  38 {
  39         Column column = table->GetColumn(m_StdAttr);
  40
  41         Value value = column.ExtractValue(row);
  42
  43         StdAggregatorState *pstate = EnsureState(state);
  44
  45         pstate->StdSum += value;
  46         pstate->StdQSum += pow(value, 2);
  47         pstate->StdCount++;
  48 }
  49
  50 double StdAggregator::GetResultAndFreeState(AggregatorState *state) const
  51 {
  52         StdAggregatorState *pstate = EnsureState(&state);
  53         double result = sqrt((pstate->StdQSum - (1 / pstate->StdCount) * pow(pstate->StdSum, 2)) / (pstate->StdCount - 1));
  54         delete pstate;
  55
  56         return result;
  57 }