Logo ROOT   6.10/09
Reference Guide
SVKernelMatrix.cxx
Go to the documentation of this file.
1 // @(#)root/tmva $Id$
2 // Author: Andrzej Zemla
3 
4 /**********************************************************************************
5  * Project: TMVA - a Root-integrated toolkit for multivariate data analysis *
6  * Package: TMVA *
7  * Class : SVKernelMatrix *
8  * Web : http://tmva.sourceforge.net *
9  * *
10  * Description: *
11  * Implementation *
12  * *
13  * Authors (alphabetical): *
14  * Marcin Wolter <Marcin.Wolter@cern.ch> - IFJ PAN, Krakow, Poland *
15  * Andrzej Zemla <azemla@cern.ch> - IFJ PAN, Krakow, Poland *
16  * (IFJ PAN: Henryk Niewodniczanski Inst. Nucl. Physics, Krakow, Poland) *
17  * *
18  * Minor modification to improve optimisation of kernel values: *
19  * Adrian Bevan <adrian.bevan@cern.ch> - Queen Mary *
20  * University of London, UK *
21  * Tom Stevenson <thomas.james.stevenson@cern.ch> - Queen Mary *
22  * University of London, UK *
23  * *
24  * Copyright (c) 2005: *
25  * CERN, Switzerland *
26  * MPI-K Heidelberg, Germany *
27  * PAN, Krakow, Poland *
28  * *
29  * Redistribution and use in source and binary forms, with or without *
30  * modification, are permitted according to the terms listed in LICENSE *
31  * (http://tmva.sourceforge.net/LICENSE) *
32  **********************************************************************************/
33 
34 /*! \class TMVA::SVKernelMatrix
35 \ingroup TMVA
36 Kernel matrix for Support Vector Machine
37 */
38 
39 #include "TMVA/SVKernelMatrix.h"
40 
41 #include "TMVA/MsgLogger.h"
42 #include "TMVA/SVEvent.h"
43 #include "TMVA/SVKernelFunction.h"
44 #include "TMVA/Types.h"
45 
46 #include "RtypesCore.h"
47 
48 #include <iostream>
49 #include <stdexcept>
50 
51 ////////////////////////////////////////////////////////////////////////////////
52 /// constructor
53 
55  : fSize(0),
56  fKernelFunction(0),
57  fSVKernelMatrix(0),
58  fLogger( new MsgLogger("ResultsRegression", kINFO) )
59 {
60 }
61 
62 ////////////////////////////////////////////////////////////////////////////////
63 /// constructor
64 
65 TMVA::SVKernelMatrix::SVKernelMatrix( std::vector<TMVA::SVEvent*>* inputVectors, SVKernelFunction* kernelFunction )
66  : fSize(inputVectors->size()),
67  fKernelFunction(kernelFunction),
68  fLogger( new MsgLogger("SVKernelMatrix", kINFO) )
69 {
71  try{
72  for (UInt_t i = 0; i < fSize; i++) fSVKernelMatrix[i] = new Float_t[i+1];
73  }catch(...){
74  Log() << kFATAL << "Input data too large. Not enough memory to allocate memory for Support Vector Kernel Matrix. Please reduce the number of input events or use a different method."<<Endl;
75  }
76  // We compute the diagonal and one half of the off diagonal. When reading back we use
77  // the symmetry of i,j to j,i to ensure the correct values are returned.
78  for (UInt_t i = 0; i < fSize; i++) {
79  for (UInt_t j = 0; j <=i; j++) {
80  fSVKernelMatrix[i][j] = fKernelFunction->Evaluate((*inputVectors)[i], (*inputVectors)[j]);
81  }
82  }
83 }
84 
85 ////////////////////////////////////////////////////////////////////////////////
86 /// destructor
87 
89 {
90  for (UInt_t i = fSize -1; i > 0; i--) {
91  delete[] fSVKernelMatrix[i];
92  fSVKernelMatrix[i] = 0;
93  }
94  delete[] fSVKernelMatrix;
95  fSVKernelMatrix = 0;
96 }
97 
98 ////////////////////////////////////////////////////////////////////////////////
99 /// returns a row of the kernel matrix
100 
102 {
103  Float_t* fLine = NULL;
104  if (line >= fSize) {
105  return NULL;
106  }
107  else {
108  fLine = new Float_t[fSize];
109  for( UInt_t i = 0; i <line; i++)
110  fLine[i] = fSVKernelMatrix[line][i];
111  for( UInt_t i = line; i < fSize; i++)
112  fLine[i] = fSVKernelMatrix[i][line];
113  return fLine;
114  }
115 }
116 
117 ////////////////////////////////////////////////////////////////////////////////
118 /// returns an element of the kernel matrix
119 
121 {
122  if (i > j) return fSVKernelMatrix[i][j];
123  else return fSVKernelMatrix[j][i]; // it's symmetric, ;)
124 }
Kernel for Support Vector Machine.
MsgLogger & Endl(MsgLogger &ml)
Definition: MsgLogger.h:158
Float_t * GetLine(UInt_t)
returns a row of the kernel matrix
TLine * line
float Float_t
Definition: RtypesCore.h:53
#define NULL
Definition: RtypesCore.h:88
SVKernelFunction * fKernelFunction
Float_t ** fSVKernelMatrix
MsgLogger & Log() const
message logger
Float_t GetElement(UInt_t i, UInt_t j)
returns an element of the kernel matrix
~SVKernelMatrix()
destructor
unsigned int UInt_t
Definition: RtypesCore.h:42
ostringstream derivative to redirect and format output
Definition: MsgLogger.h:59
SVKernelMatrix()
constructor
Float_t Evaluate(SVEvent *ev1, SVEvent *ev2)