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

   1 /* Icinga 2 | (c) 2012 Icinga GmbH | GPLv2+ */
   2
   3 #include "livestatus/stdaggregator.hpp"
   4 #include <math.h>
   5
   6 using namespace icinga;
   7
   8 StdAggregator::StdAggregator(String attr)
   9         : m_StdAttr(std::move(attr))
  10 { }
  11
  12 StdAggregatorState *StdAggregator::EnsureState(AggregatorState **state)
  13 {
  14         if (!*state)
  15                 *state = new StdAggregatorState();
  16
  17         return static_cast<StdAggregatorState *>(*state);
  18 }
  19
  20 void StdAggregator::Apply(const Table::Ptr& table, const Value& row, AggregatorState **state)
  21 {
  22         Column column = table->GetColumn(m_StdAttr);
  23
  24         Value value = column.ExtractValue(row);
  25
  26         StdAggregatorState *pstate = EnsureState(state);
  27
  28         pstate->StdSum += value;
  29         pstate->StdQSum += pow(value, 2);
  30         pstate->StdCount++;
  31 }
  32
  33 double StdAggregator::GetResultAndFreeState(AggregatorState *state) const
  34 {
  35         StdAggregatorState *pstate = EnsureState(&state);
  36         double result = sqrt((pstate->StdQSum - (1 / pstate->StdCount) * pow(pstate->StdSum, 2)) / (pstate->StdCount - 1));
  37         delete pstate;
  38
  39         return result;
  40 }