test/matching_test.cc
author Peter Kovacs <kpeter@inf.elte.hu>
Tue, 15 Mar 2011 19:32:21 +0100
changeset 1047 ddd3c0d3d9bf
parent 949 61120524af27
child 1173 d216e1c8b3fa
permissions -rw-r--r--
Implement the scaling Price Refinement heuristic in CostScaling (#417)
instead of Early Termination.

These two heuristics are similar, but the newer one is faster
and not only makes it possible to skip some epsilon phases, but
it can improve the performance of the other phases, as well.
     1 /* -*- mode: C++; indent-tabs-mode: nil; -*-
     2  *
     3  * This file is a part of LEMON, a generic C++ optimization library.
     4  *
     5  * Copyright (C) 2003-2010
     6  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     7  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     8  *
     9  * Permission to use, modify and distribute this software is granted
    10  * provided that this copyright notice appears in all copies. For
    11  * precise terms see the accompanying LICENSE file.
    12  *
    13  * This software is provided "AS IS" with no warranty of any kind,
    14  * express or implied, and with no claim as to its suitability for any
    15  * purpose.
    16  *
    17  */
    18 
    19 #include <iostream>
    20 #include <sstream>
    21 #include <vector>
    22 #include <queue>
    23 #include <cstdlib>
    24 
    25 #include <lemon/matching.h>
    26 #include <lemon/smart_graph.h>
    27 #include <lemon/concepts/graph.h>
    28 #include <lemon/concepts/maps.h>
    29 #include <lemon/lgf_reader.h>
    30 #include <lemon/math.h>
    31 
    32 #include "test_tools.h"
    33 
    34 using namespace std;
    35 using namespace lemon;
    36 
    37 GRAPH_TYPEDEFS(SmartGraph);
    38 
    39 
    40 const int lgfn = 3;
    41 const std::string lgf[lgfn] = {
    42   "@nodes\n"
    43   "label\n"
    44   "0\n"
    45   "1\n"
    46   "2\n"
    47   "3\n"
    48   "4\n"
    49   "5\n"
    50   "6\n"
    51   "7\n"
    52   "@edges\n"
    53   "     label  weight\n"
    54   "7 4  0      984\n"
    55   "0 7  1      73\n"
    56   "7 1  2      204\n"
    57   "2 3  3      583\n"
    58   "2 7  4      565\n"
    59   "2 1  5      582\n"
    60   "0 4  6      551\n"
    61   "2 5  7      385\n"
    62   "1 5  8      561\n"
    63   "5 3  9      484\n"
    64   "7 5  10     904\n"
    65   "3 6  11     47\n"
    66   "7 6  12     888\n"
    67   "3 0  13     747\n"
    68   "6 1  14     310\n",
    69 
    70   "@nodes\n"
    71   "label\n"
    72   "0\n"
    73   "1\n"
    74   "2\n"
    75   "3\n"
    76   "4\n"
    77   "5\n"
    78   "6\n"
    79   "7\n"
    80   "@edges\n"
    81   "     label  weight\n"
    82   "2 5  0      710\n"
    83   "0 5  1      241\n"
    84   "2 4  2      856\n"
    85   "2 6  3      762\n"
    86   "4 1  4      747\n"
    87   "6 1  5      962\n"
    88   "4 7  6      723\n"
    89   "1 7  7      661\n"
    90   "2 3  8      376\n"
    91   "1 0  9      416\n"
    92   "6 7  10     391\n",
    93 
    94   "@nodes\n"
    95   "label\n"
    96   "0\n"
    97   "1\n"
    98   "2\n"
    99   "3\n"
   100   "4\n"
   101   "5\n"
   102   "6\n"
   103   "7\n"
   104   "@edges\n"
   105   "     label  weight\n"
   106   "6 2  0      553\n"
   107   "0 7  1      653\n"
   108   "6 3  2      22\n"
   109   "4 7  3      846\n"
   110   "7 2  4      981\n"
   111   "7 6  5      250\n"
   112   "5 2  6      539\n",
   113 };
   114 
   115 void checkMaxMatchingCompile()
   116 {
   117   typedef concepts::Graph Graph;
   118   typedef Graph::Node Node;
   119   typedef Graph::Edge Edge;
   120   typedef Graph::EdgeMap<bool> MatMap;
   121 
   122   Graph g;
   123   Node n;
   124   Edge e;
   125   MatMap mat(g);
   126 
   127   MaxMatching<Graph> mat_test(g);
   128   const MaxMatching<Graph>&
   129     const_mat_test = mat_test;
   130 
   131   mat_test.init();
   132   mat_test.greedyInit();
   133   mat_test.matchingInit(mat);
   134   mat_test.startSparse();
   135   mat_test.startDense();
   136   mat_test.run();
   137 
   138   const_mat_test.matchingSize();
   139   const_mat_test.matching(e);
   140   const_mat_test.matching(n);
   141   const MaxMatching<Graph>::MatchingMap& mmap =
   142     const_mat_test.matchingMap();
   143   e = mmap[n];
   144   const_mat_test.mate(n);
   145 
   146   MaxMatching<Graph>::Status stat =
   147     const_mat_test.status(n);
   148   const MaxMatching<Graph>::StatusMap& smap =
   149     const_mat_test.statusMap();
   150   stat = smap[n];
   151   const_mat_test.barrier(n);
   152 }
   153 
   154 void checkMaxWeightedMatchingCompile()
   155 {
   156   typedef concepts::Graph Graph;
   157   typedef Graph::Node Node;
   158   typedef Graph::Edge Edge;
   159   typedef Graph::EdgeMap<int> WeightMap;
   160 
   161   Graph g;
   162   Node n;
   163   Edge e;
   164   WeightMap w(g);
   165 
   166   MaxWeightedMatching<Graph> mat_test(g, w);
   167   const MaxWeightedMatching<Graph>&
   168     const_mat_test = mat_test;
   169 
   170   mat_test.init();
   171   mat_test.start();
   172   mat_test.run();
   173 
   174   const_mat_test.matchingWeight();
   175   const_mat_test.matchingSize();
   176   const_mat_test.matching(e);
   177   const_mat_test.matching(n);
   178   const MaxWeightedMatching<Graph>::MatchingMap& mmap =
   179     const_mat_test.matchingMap();
   180   e = mmap[n];
   181   const_mat_test.mate(n);
   182 
   183   int k = 0;
   184   const_mat_test.dualValue();
   185   const_mat_test.nodeValue(n);
   186   const_mat_test.blossomNum();
   187   const_mat_test.blossomSize(k);
   188   const_mat_test.blossomValue(k);
   189 }
   190 
   191 void checkMaxWeightedPerfectMatchingCompile()
   192 {
   193   typedef concepts::Graph Graph;
   194   typedef Graph::Node Node;
   195   typedef Graph::Edge Edge;
   196   typedef Graph::EdgeMap<int> WeightMap;
   197 
   198   Graph g;
   199   Node n;
   200   Edge e;
   201   WeightMap w(g);
   202 
   203   MaxWeightedPerfectMatching<Graph> mat_test(g, w);
   204   const MaxWeightedPerfectMatching<Graph>&
   205     const_mat_test = mat_test;
   206 
   207   mat_test.init();
   208   mat_test.start();
   209   mat_test.run();
   210 
   211   const_mat_test.matchingWeight();
   212   const_mat_test.matching(e);
   213   const_mat_test.matching(n);
   214   const MaxWeightedPerfectMatching<Graph>::MatchingMap& mmap =
   215     const_mat_test.matchingMap();
   216   e = mmap[n];
   217   const_mat_test.mate(n);
   218 
   219   int k = 0;
   220   const_mat_test.dualValue();
   221   const_mat_test.nodeValue(n);
   222   const_mat_test.blossomNum();
   223   const_mat_test.blossomSize(k);
   224   const_mat_test.blossomValue(k);
   225 }
   226 
   227 void checkMatching(const SmartGraph& graph,
   228                    const MaxMatching<SmartGraph>& mm) {
   229   int num = 0;
   230 
   231   IntNodeMap comp_index(graph);
   232   UnionFind<IntNodeMap> comp(comp_index);
   233 
   234   int barrier_num = 0;
   235 
   236   for (NodeIt n(graph); n != INVALID; ++n) {
   237     check(mm.status(n) == MaxMatching<SmartGraph>::EVEN ||
   238           mm.matching(n) != INVALID, "Wrong Gallai-Edmonds decomposition");
   239     if (mm.status(n) == MaxMatching<SmartGraph>::ODD) {
   240       ++barrier_num;
   241     } else {
   242       comp.insert(n);
   243     }
   244   }
   245 
   246   for (EdgeIt e(graph); e != INVALID; ++e) {
   247     if (mm.matching(e)) {
   248       check(e == mm.matching(graph.u(e)), "Wrong matching");
   249       check(e == mm.matching(graph.v(e)), "Wrong matching");
   250       ++num;
   251     }
   252     check(mm.status(graph.u(e)) != MaxMatching<SmartGraph>::EVEN ||
   253           mm.status(graph.v(e)) != MaxMatching<SmartGraph>::MATCHED,
   254           "Wrong Gallai-Edmonds decomposition");
   255 
   256     check(mm.status(graph.v(e)) != MaxMatching<SmartGraph>::EVEN ||
   257           mm.status(graph.u(e)) != MaxMatching<SmartGraph>::MATCHED,
   258           "Wrong Gallai-Edmonds decomposition");
   259 
   260     if (mm.status(graph.u(e)) != MaxMatching<SmartGraph>::ODD &&
   261         mm.status(graph.v(e)) != MaxMatching<SmartGraph>::ODD) {
   262       comp.join(graph.u(e), graph.v(e));
   263     }
   264   }
   265 
   266   std::set<int> comp_root;
   267   int odd_comp_num = 0;
   268   for (NodeIt n(graph); n != INVALID; ++n) {
   269     if (mm.status(n) != MaxMatching<SmartGraph>::ODD) {
   270       int root = comp.find(n);
   271       if (comp_root.find(root) == comp_root.end()) {
   272         comp_root.insert(root);
   273         if (comp.size(n) % 2 == 1) {
   274           ++odd_comp_num;
   275         }
   276       }
   277     }
   278   }
   279 
   280   check(mm.matchingSize() == num, "Wrong matching");
   281   check(2 * num == countNodes(graph) - (odd_comp_num - barrier_num),
   282          "Wrong matching");
   283   return;
   284 }
   285 
   286 void checkWeightedMatching(const SmartGraph& graph,
   287                    const SmartGraph::EdgeMap<int>& weight,
   288                    const MaxWeightedMatching<SmartGraph>& mwm) {
   289   for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) {
   290     if (graph.u(e) == graph.v(e)) continue;
   291     int rw = mwm.nodeValue(graph.u(e)) + mwm.nodeValue(graph.v(e));
   292 
   293     for (int i = 0; i < mwm.blossomNum(); ++i) {
   294       bool s = false, t = false;
   295       for (MaxWeightedMatching<SmartGraph>::BlossomIt n(mwm, i);
   296            n != INVALID; ++n) {
   297         if (graph.u(e) == n) s = true;
   298         if (graph.v(e) == n) t = true;
   299       }
   300       if (s == true && t == true) {
   301         rw += mwm.blossomValue(i);
   302       }
   303     }
   304     rw -= weight[e] * mwm.dualScale;
   305 
   306     check(rw >= 0, "Negative reduced weight");
   307     check(rw == 0 || !mwm.matching(e),
   308           "Non-zero reduced weight on matching edge");
   309   }
   310 
   311   int pv = 0;
   312   for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) {
   313     if (mwm.matching(n) != INVALID) {
   314       check(mwm.nodeValue(n) >= 0, "Invalid node value");
   315       pv += weight[mwm.matching(n)];
   316       SmartGraph::Node o = graph.target(mwm.matching(n));
   317       check(mwm.mate(n) == o, "Invalid matching");
   318       check(mwm.matching(n) == graph.oppositeArc(mwm.matching(o)),
   319             "Invalid matching");
   320     } else {
   321       check(mwm.mate(n) == INVALID, "Invalid matching");
   322       check(mwm.nodeValue(n) == 0, "Invalid matching");
   323     }
   324   }
   325 
   326   int dv = 0;
   327   for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) {
   328     dv += mwm.nodeValue(n);
   329   }
   330 
   331   for (int i = 0; i < mwm.blossomNum(); ++i) {
   332     check(mwm.blossomValue(i) >= 0, "Invalid blossom value");
   333     check(mwm.blossomSize(i) % 2 == 1, "Even blossom size");
   334     dv += mwm.blossomValue(i) * ((mwm.blossomSize(i) - 1) / 2);
   335   }
   336 
   337   check(pv * mwm.dualScale == dv * 2, "Wrong duality");
   338 
   339   return;
   340 }
   341 
   342 void checkWeightedPerfectMatching(const SmartGraph& graph,
   343                           const SmartGraph::EdgeMap<int>& weight,
   344                           const MaxWeightedPerfectMatching<SmartGraph>& mwpm) {
   345   for (SmartGraph::EdgeIt e(graph); e != INVALID; ++e) {
   346     if (graph.u(e) == graph.v(e)) continue;
   347     int rw = mwpm.nodeValue(graph.u(e)) + mwpm.nodeValue(graph.v(e));
   348 
   349     for (int i = 0; i < mwpm.blossomNum(); ++i) {
   350       bool s = false, t = false;
   351       for (MaxWeightedPerfectMatching<SmartGraph>::BlossomIt n(mwpm, i);
   352            n != INVALID; ++n) {
   353         if (graph.u(e) == n) s = true;
   354         if (graph.v(e) == n) t = true;
   355       }
   356       if (s == true && t == true) {
   357         rw += mwpm.blossomValue(i);
   358       }
   359     }
   360     rw -= weight[e] * mwpm.dualScale;
   361 
   362     check(rw >= 0, "Negative reduced weight");
   363     check(rw == 0 || !mwpm.matching(e),
   364           "Non-zero reduced weight on matching edge");
   365   }
   366 
   367   int pv = 0;
   368   for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) {
   369     check(mwpm.matching(n) != INVALID, "Non perfect");
   370     pv += weight[mwpm.matching(n)];
   371     SmartGraph::Node o = graph.target(mwpm.matching(n));
   372     check(mwpm.mate(n) == o, "Invalid matching");
   373     check(mwpm.matching(n) == graph.oppositeArc(mwpm.matching(o)),
   374           "Invalid matching");
   375   }
   376 
   377   int dv = 0;
   378   for (SmartGraph::NodeIt n(graph); n != INVALID; ++n) {
   379     dv += mwpm.nodeValue(n);
   380   }
   381 
   382   for (int i = 0; i < mwpm.blossomNum(); ++i) {
   383     check(mwpm.blossomValue(i) >= 0, "Invalid blossom value");
   384     check(mwpm.blossomSize(i) % 2 == 1, "Even blossom size");
   385     dv += mwpm.blossomValue(i) * ((mwpm.blossomSize(i) - 1) / 2);
   386   }
   387 
   388   check(pv * mwpm.dualScale == dv * 2, "Wrong duality");
   389 
   390   return;
   391 }
   392 
   393 
   394 int main() {
   395 
   396   for (int i = 0; i < lgfn; ++i) {
   397     SmartGraph graph;
   398     SmartGraph::EdgeMap<int> weight(graph);
   399 
   400     istringstream lgfs(lgf[i]);
   401     graphReader(graph, lgfs).
   402       edgeMap("weight", weight).run();
   403 
   404     bool perfect;
   405     {
   406       MaxMatching<SmartGraph> mm(graph);
   407       mm.run();
   408       checkMatching(graph, mm);
   409       perfect = 2 * mm.matchingSize() == countNodes(graph);
   410     }
   411 
   412     {
   413       MaxWeightedMatching<SmartGraph> mwm(graph, weight);
   414       mwm.run();
   415       checkWeightedMatching(graph, weight, mwm);
   416     }
   417 
   418     {
   419       MaxWeightedMatching<SmartGraph> mwm(graph, weight);
   420       mwm.init();
   421       mwm.start();
   422       checkWeightedMatching(graph, weight, mwm);
   423     }
   424 
   425     {
   426       MaxWeightedPerfectMatching<SmartGraph> mwpm(graph, weight);
   427       bool result = mwpm.run();
   428 
   429       check(result == perfect, "Perfect matching found");
   430       if (perfect) {
   431         checkWeightedPerfectMatching(graph, weight, mwpm);
   432       }
   433     }
   434 
   435     {
   436       MaxWeightedPerfectMatching<SmartGraph> mwpm(graph, weight);
   437       mwpm.init();
   438       bool result = mwpm.start();
   439 
   440       check(result == perfect, "Perfect matching found");
   441       if (perfect) {
   442         checkWeightedPerfectMatching(graph, weight, mwpm);
   443       }
   444     }
   445   }
   446 
   447   return 0;
   448 }