fastjet/contrib/ShapeWithPartition.hh

0001 // $Id: ShapeWithPartition.hh 859 2015-09-21 10:11:32Z gsalam $
0002 //
0003 // Copyright (c) 2012-, Matteo Cacciari, Jihun Kim, Gavin P. Salam and Gregory Soyez
0004 //
0005 //----------------------------------------------------------------------
0006 // This file is part of FastJet contrib.
0007 //
0008 // It is free software; you can redistribute it and/or modify it under
0009 // the terms of the GNU General Public License as published by the
0010 // Free Software Foundation; either version 2 of the License, or (at
0011 // your option) any later version.
0012 //
0013 // It is distributed in the hope that it will be useful, but WITHOUT
0014 // ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
0015 // or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
0016 // License for more details.
0017 //
0018 // You should have received a copy of the GNU General Public License
0019 // along with this code. If not, see <http://www.gnu.org/licenses/>.
0020 //----------------------------------------------------------------------
0021
0022 #ifndef __FASTJET_CONTRIB_SHAPE_WITH_PARTITION_HH__
0023 #define __FASTJET_CONTRIB_SHAPE_WITH_PARTITION_HH__
0024
0025 #include "fastjet/FunctionOfPseudoJet.hh"
0026
0027 FASTJET_BEGIN_NAMESPACE
0028
0029 namespace contrib{
0030
0031 //------------------------------------------------------------------------
0032 /// \class ShapeWithPartition
0033 ///
0034 /// This class describes a shape where the partitioning has been
0035 /// disconnected from the result of the shape (obtained from that
0036 /// pre-computed partition)
0037 ///
0038 /// This is meant to be a helper for operations in which we want to
0039 /// recompute the result several times while keeping the partition
0040 /// fixed (such as GenericSubtraction for which this would avoid any
0041 /// back-reaction effect)
0042 class ShapeWithPartition : public FunctionOfPseudoJet<double>{
0043 public:
0044   /// just a reminder that one has to define this too in derived classes
0045   virtual std::string description() const = 0;
0046
0047   /// compute the partition associated with a given jet.
0048   /// It is returned under the form of a composite jet.
0049   virtual PseudoJet partition(const PseudoJet &jet) const = 0;
0050
0051   /// return the result of the shape computed from a given partition
0052   virtual double result_from_partition(const PseudoJet &partit) const = 0;
0053
0054   /// the overall result of the shape. This is nothing that the
0055   /// "result_from_partition" obtained from the partition of the given
0056   /// jet.
0057   virtual double result(const PseudoJet &jet) const{
0058     return result_from_partition(partition(jet));
0059   }
0060 };
0061
0062 } // namespace contrib
0063
0064 FASTJET_END_NAMESPACE
0065
0066 #endif // __FASTJET_CONTRIB_SHAPE_WITH_PARTITION_HH__