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Reference Guide
TActivationIdentity.h
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1// @(#)root/tmva $Id$
2// Author: Matt Jachowski
3
4/**********************************************************************************
5 * Project: TMVA - a Root-integrated toolkit for multivariate data analysis *
6 * Package: TMVA *
7 * Class : TMVA::TActivationIdentity *
8 * Web : http://tmva.sourceforge.net *
9 * *
10 * Description: *
11 * Identity activation function for TNeuron *
12 * *
13 * Authors (alphabetical): *
14 * Matt Jachowski <jachowski@stanford.edu> - Stanford University, USA *
15 * *
16 * Copyright (c) 2005: *
17 * CERN, Switzerland *
18 * *
19 * Redistribution and use in source and binary forms, with or without *
20 * modification, are permitted according to the terms listed in LICENSE *
21 * (http://tmva.sourceforge.net/LICENSE) *
22 **********************************************************************************/
23
24#ifndef ROOT_TMVA_TActivationIdentity
25#define ROOT_TMVA_TActivationIdentity
26
27//////////////////////////////////////////////////////////////////////////
28// //
29// TActivationIdentity //
30// //
31// Identity activation function for TNeuron //
32// //
33//////////////////////////////////////////////////////////////////////////
34
35#include "TString.h"
36
37#include "TMVA/TActivation.h"
38
39namespace TMVA {
40
42
43 public:
44
47
48 // evaluate the activation function
49 virtual Double_t Eval(Double_t arg) { return arg; } // f(x) = x
50
51 // evaluate the derivative of the activation function
53 return 1; // f'(x) = 1
54 }
55
56 // minimum of the range of the activation function
57 virtual Double_t GetMin() { return 0; } // these should never be called
58
59 // maximum of the range of the activation function
60 virtual Double_t GetMax() { return 1; } // these should never be called
61
62 // expression for activation function
63 virtual TString GetExpression() { return "x\t1"; }
64
65 // writer of function code
66 virtual void MakeFunction(std::ostream& fout, const TString& fncName);
67
68 private:
69
70 ClassDef(TActivationIdentity,0); // Identity activation function for TNeuron
71 };
72
73} // namespace TMVA
74
75#endif
double Double_t
Definition: RtypesCore.h:55
#define ClassDef(name, id)
Definition: Rtypes.h:326
Identity activation function for TNeuron.
virtual TString GetExpression()
virtual Double_t EvalDerivative(Double_t)
virtual Double_t Eval(Double_t arg)
virtual void MakeFunction(std::ostream &fout, const TString &fncName)
writes the identity function source code
Interface for TNeuron activation function classes.
Definition: TActivation.h:42
Basic string class.
Definition: TString.h:131
create variable transformations