QMcBeaver: QMCLineSearchStepLengthSelectionFactory.cpp Source File

00001 //            QMcBeaver
00002 //
00003 //         Constructed by 
00004 //
00005 //     Michael Todd Feldmann 
00006 //              and 
00007 //   David Randall "Chip" Kent IV
00008 //
00009 // Copyright 2000.  All rights reserved.
00010 //
00011 // drkent@users.sourceforge.net mtfeldmann@users.sourceforge.net
00012 
00013 #include "QMCLineSearchStepLengthSelectionFactory.h"
00014 #include "QMCMikesBracketingStepLengthSelector.h"
00015 #include "QMCWolfeStepLengthSelector.h"
00016 #include "QMCValueStepLength.h"
00017 #include "QMCLinearizeStepLength.h"
00018 
00019 QMCLineSearchStepLengthSelectionAlgorithm * 
00020   QMCLineSearchStepLengthSelectionFactory::factory(string & Type)
00021 {
00022   QMCLineSearchStepLengthSelectionAlgorithm * algorithm = 0;
00023 
00024   double value = 0;
00025 
00026   char ** ptr = 0;
00027   value = strtod(Type.c_str(), ptr);
00028 
00029   if( Type == "MikesBracketing" )
00030     {
00031       algorithm = new QMCMikesBracketingStepLengthSelector();
00032     }
00033   else if( Type == "Wolfe" )
00034     {
00035       algorithm = new QMCWolfeStepLengthSelector();
00036     }
00037   else if( Type == "Linearize" )
00038     {
00039       algorithm = new QMCLinearizeStepLength();
00040     }
00041   else if( Type == "None" )
00042     {
00043       algorithm = new QMCValueStepLength(1.0);
00044     }
00045   else if( fabs(value) > 1.0e-10 )
00046     {
00047       algorithm = new QMCValueStepLength(value);
00048     }
00049   else
00050     {
00051       cerr << "ERROR: Unknown line search step length selection algorithm (" 
00052            << Type
00053            << ") being assigned in QMCLineSearchStepLengthSelectionFactory!" 
00054            << endl;
00055       exit(0);
00056     }
00057 
00058   return algorithm;
00059 }