1 // Ceres Solver - A fast non-linear least squares minimizer 2 // Copyright 2013 Google Inc. All rights reserved. 3 // http://code.google.com/p/ceres-solver/ 4 // 5 // Redistribution and use in source and binary forms, with or without 6 // modification, are permitted provided that the following conditions are met: 7 // 8 // * Redistributions of source code must retain the above copyright notice, 9 // this list of conditions and the following disclaimer. 10 // * Redistributions in binary form must reproduce the above copyright notice, 11 // this list of conditions and the following disclaimer in the documentation 12 // and/or other materials provided with the distribution. 13 // * Neither the name of Google Inc. nor the names of its contributors may be 14 // used to endorse or promote products derived from this software without 15 // specific prior written permission. 16 // 17 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 18 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 21 // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22 // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23 // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24 // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25 // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27 // POSSIBILITY OF SUCH DAMAGE. 28 // 29 // Author: Sameer Agarwal (sameeragarwal (at) google.com) 30 31 // This include must come before any #ifndef check on Ceres compile options. 32 #include "ceres/internal/port.h" 33 34 #ifndef CERES_NO_SUITESPARSE 35 36 #include "ceres/single_linkage_clustering.h" 37 38 #include "ceres/collections_port.h" 39 #include "ceres/graph.h" 40 #include "gtest/gtest.h" 41 42 namespace ceres { 43 namespace internal { 44 45 TEST(SingleLinkageClustering, GraphHasTwoComponents) { 46 Graph<int> graph; 47 const int kNumVertices = 6; 48 for (int i = 0; i < kNumVertices; ++i) { 49 graph.AddVertex(i); 50 } 51 // Graph structure: 52 // 53 // 0-1-2-3 4-5 54 graph.AddEdge(0, 1, 1.0); 55 graph.AddEdge(1, 2, 1.0); 56 graph.AddEdge(2, 3, 1.0); 57 graph.AddEdge(4, 5, 1.0); 58 59 SingleLinkageClusteringOptions options; 60 HashMap<int, int> membership; 61 ComputeSingleLinkageClustering(options, graph, &membership); 62 EXPECT_EQ(membership.size(), kNumVertices); 63 64 EXPECT_EQ(membership[1], membership[0]); 65 EXPECT_EQ(membership[2], membership[0]); 66 EXPECT_EQ(membership[3], membership[0]); 67 EXPECT_NE(membership[4], membership[0]); 68 EXPECT_NE(membership[5], membership[0]); 69 EXPECT_EQ(membership[4], membership[5]); 70 } 71 72 TEST(SingleLinkageClustering, ComponentWithWeakLink) { 73 Graph<int> graph; 74 const int kNumVertices = 6; 75 for (int i = 0; i < kNumVertices; ++i) { 76 graph.AddVertex(i); 77 } 78 // Graph structure: 79 // 80 // 0-1-2-3 4-5 81 graph.AddEdge(0, 1, 1.0); 82 graph.AddEdge(1, 2, 1.0); 83 graph.AddEdge(2, 3, 1.0); 84 85 // This component should break up into two. 86 graph.AddEdge(4, 5, 0.5); 87 88 SingleLinkageClusteringOptions options; 89 HashMap<int, int> membership; 90 ComputeSingleLinkageClustering(options, graph, &membership); 91 EXPECT_EQ(membership.size(), kNumVertices); 92 93 EXPECT_EQ(membership[1], membership[0]); 94 EXPECT_EQ(membership[2], membership[0]); 95 EXPECT_EQ(membership[3], membership[0]); 96 EXPECT_NE(membership[4], membership[0]); 97 EXPECT_NE(membership[5], membership[0]); 98 EXPECT_NE(membership[4], membership[5]); 99 } 100 101 TEST(SingleLinkageClustering, ComponentWithWeakLinkAndStrongLink) { 102 Graph<int> graph; 103 const int kNumVertices = 6; 104 for (int i = 0; i < kNumVertices; ++i) { 105 graph.AddVertex(i); 106 } 107 // Graph structure: 108 // 109 // 0-1-2-3 4-5 110 graph.AddEdge(0, 1, 1.0); 111 graph.AddEdge(1, 2, 1.0); 112 graph.AddEdge(2, 3, 0.5); // Weak link 113 graph.AddEdge(0, 3, 1.0); 114 115 // This component should break up into two. 116 graph.AddEdge(4, 5, 1.0); 117 118 SingleLinkageClusteringOptions options; 119 HashMap<int, int> membership; 120 ComputeSingleLinkageClustering(options, graph, &membership); 121 EXPECT_EQ(membership.size(), kNumVertices); 122 123 EXPECT_EQ(membership[1], membership[0]); 124 EXPECT_EQ(membership[2], membership[0]); 125 EXPECT_EQ(membership[3], membership[0]); 126 EXPECT_EQ(membership[4], membership[5]); 127 } 128 129 } // namespace internal 130 } // namespace ceres 131 132 #endif // CERES_NO_SUITESPARSE 133
