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/
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29 // Author: sameeragarwal@google.com (Sameer Agarwal)
30 
31 #ifndef CERES_INTERNAL_SINGLE_LINKAGE_CLUSTERING_H_
32 #define CERES_INTERNAL_SINGLE_LINKAGE_CLUSTERING_H_
33 
34 // This include must come before any #ifndef check on Ceres compile options.
35 #include "ceres/internal/port.h"
36 
37 #ifndef CERES_NO_SUITESPARSE
38 
39 #include "ceres/collections_port.h"
40 #include "ceres/graph.h"
41 
42 namespace ceres {
43 namespace internal {
44 
45 struct SingleLinkageClusteringOptions {
SingleLinkageClusteringOptionsSingleLinkageClusteringOptions46   SingleLinkageClusteringOptions()
47       : min_similarity(0.99) {
48   }
49 
50   // Graph edges with edge weight less than min_similarity are ignored
51   // during the clustering process.
52   double min_similarity;
53 };
54 
55 // Compute a partitioning of the vertices of the graph using the
56 // single linkage clustering algorithm. Edges with weight less than
57 // SingleLinkageClusteringOptions::min_similarity will be ignored.
58 //
59 // membership upon return will contain a mapping from the vertices of
60 // the graph to an integer indicating the identity of the cluster that
61 // it belongs to.
62 //
63 // The return value of this function is the number of clusters
64 // identified by the algorithm.
65 int ComputeSingleLinkageClustering(
66     const SingleLinkageClusteringOptions& options,
67     const Graph<int>& graph,
68     HashMap<int, int>* membership);
69 
70 }  // namespace internal
71 }  // namespace ceres
72 
73 #endif  // CERES_NO_SUITESPARSE
74 #endif  // CERES_INTERNAL_SINGLE_LINKAGE_CLUSTERING_H_
75