[11] | 1 | //STARTHEADER
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| 2 | // $Id: ClosestPair2DBase.hh,v 1.1 2008-11-06 14:32:09 ovyn Exp $
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| 3 | //
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| 4 | // Copyright (c) 2005-2006, Matteo Cacciari and Gavin Salam
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| 5 | //
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| 6 | //----------------------------------------------------------------------
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| 7 | // This file is part of FastJet.
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| 8 | //
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| 9 | // FastJet is free software; you can redistribute it and/or modify
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| 10 | // it under the terms of the GNU General Public License as published by
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| 11 | // the Free Software Foundation; either version 2 of the License, or
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| 12 | // (at your option) any later version.
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| 13 | //
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| 14 | // The algorithms that underlie FastJet have required considerable
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| 15 | // development and are described in hep-ph/0512210. If you use
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| 16 | // FastJet as part of work towards a scientific publication, please
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| 17 | // include a citation to the FastJet paper.
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| 18 | //
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| 19 | // FastJet is distributed in the hope that it will be useful,
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| 20 | // but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 21 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 22 | // GNU General Public License for more details.
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| 23 | //
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| 24 | // You should have received a copy of the GNU General Public License
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| 25 | // along with FastJet; if not, write to the Free Software
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| 26 | // Foundation, Inc.:
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| 27 | // 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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| 28 | //----------------------------------------------------------------------
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| 29 | //ENDHEADER
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| 30 |
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| 31 | #ifndef __FASTJET_CLOSESTPAIR2DBASE__HH__
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| 32 | #define __FASTJET_CLOSESTPAIR2DBASE__HH__
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| 33 |
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| 34 | #include<vector>
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| 35 | #include "Utilities/Fastjet/include/fastjet/internal/base.hh"
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| 36 |
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| 37 | FASTJET_BEGIN_NAMESPACE // defined in fastjet/internal/base.hh
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| 38 |
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| 39 | //----------------------------------------------------------------------
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| 40 | /// class for representing 2d coordinates and carrying out some basic
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| 41 | /// operations on them
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| 42 | class Coord2D {
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| 43 | public:
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| 44 | double x, y;
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| 45 |
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| 46 | Coord2D() {};
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| 47 |
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| 48 | Coord2D(double a, double b): x(a), y(b) {};
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| 49 |
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| 50 | /// return the vector difference between two coordinates
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| 51 | Coord2D operator-(const Coord2D & other) const {
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| 52 | return Coord2D(x - other.x, y - other.y);};
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| 53 |
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| 54 | /// return the vector sum between two coordinates
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| 55 | Coord2D operator+(const Coord2D & other) const {
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| 56 | return Coord2D(x + other.x, y + other.y);};
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| 57 |
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| 58 | /// return the product of the coordinate with the factor
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| 59 | Coord2D operator*(double factor) const {return Coord2D(factor*x,factor*y);};
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| 60 | friend Coord2D operator*(double factor, const Coord2D & coord) {
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| 61 | return Coord2D(factor*coord.x,factor*coord.y);
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| 62 | }
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| 63 |
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| 64 | /// division of each component of coordinate
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| 65 | Coord2D operator/(double divisor) const {
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| 66 | return Coord2D(x / divisor, y / divisor);};
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| 67 |
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| 68 | /// return the squared distance between two coordinates
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| 69 | friend double distance2(const Coord2D & a, const Coord2D & b) {
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| 70 | double dx = a.x - b.x, dy = a.y-b.y;
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| 71 | return dx*dx+dy*dy;
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| 72 | };
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| 73 | /// return the squared distance between two coordinates
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| 74 | double distance2(const Coord2D & b) const {
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| 75 | double dx = x - b.x, dy = y-b.y;
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| 76 | return dx*dx+dy*dy;
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| 77 | };
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| 78 | };
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| 79 |
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| 80 |
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| 81 | //----------------------------------------------------------------------
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| 82 | /// abstract base class for finding closest pairs in 2D
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| 83 | class ClosestPair2DBase {
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| 84 | public:
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| 85 | /// provides the IDs of the closest pair as well as the squared
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| 86 | /// distance between them
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| 87 | virtual void closest_pair(unsigned int & ID1, unsigned int & ID2,
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| 88 | double & distance2) const = 0;
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| 89 |
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| 90 | /// removes the entry labelled by ID from the object;
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| 91 | virtual void remove(unsigned int ID) = 0;
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| 92 |
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| 93 | /// inserts the position into the closest pair structure and returns the
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| 94 | /// ID that has been allocated for the object.
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| 95 | virtual unsigned int insert(const Coord2D & position) = 0;
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| 96 |
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| 97 | /// replaces the specified ID1 and ID2 with something at a new position
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| 98 | /// assuming that ID1 and ID2 are in sequence wrt position; it returns
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| 99 | /// the ID of the new object...
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| 100 | virtual unsigned int replace(unsigned int ID1, unsigned int ID2,
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| 101 | const Coord2D & position) {
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| 102 | remove(ID1);
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| 103 | remove(ID2);
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| 104 | unsigned new_ID = insert(position);
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| 105 | return(new_ID);
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| 106 | };
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| 107 |
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| 108 | /// replaces IDs_to_remove with points at the new_positions
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| 109 | /// indicating the IDs allocated to the new points in new_IDs
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| 110 | virtual void replace_many(const std::vector<unsigned int> & IDs_to_remove,
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| 111 | const std::vector<Coord2D> & new_positions,
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| 112 | std::vector<unsigned int> & new_IDs) {
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| 113 | for(unsigned i = 0; i < IDs_to_remove.size(); i++) {
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| 114 | remove(IDs_to_remove[i]);}
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| 115 | new_IDs.resize(0);
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| 116 | for(unsigned i = 0; i < new_positions.size(); i++) {
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| 117 | new_IDs.push_back(insert(new_positions[i]));}
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| 118 | }
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| 119 |
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| 120 | virtual unsigned int size() = 0;
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| 121 |
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| 122 | virtual ~ClosestPair2DBase() {};
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| 123 |
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| 124 | };
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| 125 |
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| 126 |
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| 127 | FASTJET_END_NAMESPACE
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| 128 |
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| 129 | #endif // __FASTJET_CLOSESTPAIR2DBASE__HH__
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