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/data/doxygen/doxygen-1.7.3/gen/CMSSW_4_2_8/src/RecoVertex/VertexTools/src/DeterministicAnnealing.cc

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00001 #include "RecoVertex/VertexTools/interface/DeterministicAnnealing.h"
00002 #include <cmath>
00003 #include <vector>
00004 #include <iostream>
00005 #include <limits>
00006 
00007 using namespace std;
00008 
00009 namespace {
00010   vector < float > temperatures;
00011 }
00012 
00013 DeterministicAnnealing::DeterministicAnnealing ( float cutoff ) :
00014   theIndex(0), theChi2cut ( cutoff*cutoff ), theIsAnnealed ( false )
00015 {
00016   temperatures.push_back(256);
00017   temperatures.push_back(64);
00018   temperatures.push_back(16);
00019   temperatures.push_back(4);
00020   temperatures.push_back(2);
00021   temperatures.push_back(1);
00022 }
00023 
00024 DeterministicAnnealing::DeterministicAnnealing( const vector < float > & sched,
00025      float cutoff ) : theIndex(0), theChi2cut ( cutoff*cutoff ), theIsAnnealed ( false )
00026 {
00027   temperatures = sched;
00028 }
00029 
00030 void DeterministicAnnealing::anneal()
00031 {
00032   if ( theIndex < ( temperatures.size() - 1 ) )
00033   {
00034     theIndex++; 
00035   } else {
00036     theIsAnnealed = true;
00037   };
00038 }
00039 
00040 double DeterministicAnnealing::weight ( double chi2 ) const
00041 {
00042   long double mphi = phi ( chi2 );
00043   /*
00044   if ( mphi < std::numeric_limits<double>::epsilon() ) return 0.;
00045   return 1. / ( 1. + phi ( theChi2cut * theChi2cut ) / mphi );
00046   */
00047   // return mphi / ( mphi + phi ( theChi2cut ) );
00048   long double newtmp = mphi / ( mphi + phi ( theChi2cut ) );
00049   if ( std::isinf(newtmp ) )
00050   {
00051     if ( chi2 < theChi2cut ) newtmp=1.;
00052     else newtmp=0.;
00053   }
00054   return newtmp;
00055 }
00056 
00057 void DeterministicAnnealing::resetAnnealing()
00058 {
00059   theIndex=0;
00060   theIsAnnealed = false;
00061 }
00062 
00063 inline double DeterministicAnnealing::phi( double chi2 ) const
00064 {
00065   return exp ( -.5 * chi2 / temperatures[theIndex] );
00066 }
00067 
00068 double DeterministicAnnealing::cutoff() const
00069 {
00070   return sqrt(theChi2cut);
00071 }
00072 
00073 double DeterministicAnnealing::currentTemp() const
00074 {
00075   return temperatures[theIndex];
00076 }
00077 
00078 double DeterministicAnnealing::initialTemp() const
00079 {
00080   return temperatures[0];
00081 }
00082 
00083 bool DeterministicAnnealing::isAnnealed() const
00084 {
00085   return theIsAnnealed;
00086 }
00087 
00088 void DeterministicAnnealing::debug() const
00089 {
00090   cout << "[DeterministicAnnealing] schedule=";
00091   for ( vector< float >::const_iterator i=temperatures.begin(); 
00092         i!=temperatures.end() ; ++i )
00093   {
00094     cout << *i << " ";
00095   };
00096   cout << endl;
00097 }