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diff --git a/src/GudhUI/utils/Edge_contractor.h b/src/GudhUI/utils/Edge_contractor.h
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+/*    This file is part of the Gudhi Library - https://gudhi.inria.fr/ - which is released under MIT.
+ *    See file LICENSE or go to https://gudhi.inria.fr/licensing/ for full license details.
+ *    Author(s):       David Salinas
+ *
+ *    Copyright (C) 2014 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+#ifndef UTILS_EDGE_CONTRACTOR_H_
+#define UTILS_EDGE_CONTRACTOR_H_
+
+
+#include <gudhi/Skeleton_blocker_contractor.h>
+#include <gudhi/Contraction/Edge_profile.h>
+#include <gudhi/Contraction/policies/Cost_policy.h>
+
+#include <vector>
+
+/**
+ * Iteratively puts every vertex at the center of its neighbors
+ */
+template<typename SkBlComplex> class Edge_contractor {
+ private:
+  SkBlComplex& complex_;
+  unsigned num_contractions_;
+
+  /**
+   * @brief return a cost corresponding to the squared length of the edge
+   */
+  template< typename EdgeProfile> class Length_cost : public contraction::Cost_policy<EdgeProfile> {
+   public:
+    typedef typename contraction::Cost_policy<EdgeProfile>::Cost_type Cost_type;
+    typedef typename EdgeProfile::Point Point;
+
+    Cost_type operator()(const EdgeProfile& profile, const boost::optional<Point>& placement) const override {
+      Cost_type res;
+      if (!placement)
+        return res;
+      return Geometry_trait::Squared_distance_d()(profile.p0(), profile.p1());  // not working??
+    }
+  };
+
+  /**
+   * @brief return a cost corresponding to the squared length of the edge
+   */
+  template< typename EdgeProfile> class Middle_placement : public contraction::Placement_policy<EdgeProfile> {
+   public:
+    typedef typename contraction::Placement_policy<EdgeProfile>::Placement_type Placement_type;
+    typedef typename EdgeProfile::Point Point;
+
+    Placement_type operator()(const EdgeProfile& profile) const override {
+      std::vector<double> mid_coords(profile.p0().dimension(), 0);
+      for (int i = 0; i < profile.p0().dimension(); ++i) {
+        mid_coords[i] = (profile.p0()[i] + profile.p1()[i]) / 2.;
+      }
+      return Point(profile.p0().dimension(), mid_coords.begin(), mid_coords.end());
+    }
+  };
+
+ public:
+  typedef typename SkBlComplex::Vertex_handle Vertex_handle;
+  typedef typename SkBlComplex::Edge_handle Edge_handle;
+
+  /**
+   * @brief Modify complex to be the expansion of the k-nearest neighbor
+   * symetric graph.
+   */
+  Edge_contractor(SkBlComplex& complex, unsigned num_contractions) :
+      complex_(complex), num_contractions_(num_contractions) {
+    typedef typename contraction::Edge_profile<Complex> Profile;
+    num_contractions = (std::min)(static_cast<int>(num_contractions), static_cast<int>(complex_.num_vertices() - 1));
+    typedef typename contraction::Skeleton_blocker_contractor<Complex> Contractor;
+    Contractor contractor(complex_,
+                          new Length_cost<contraction::Edge_profile < Complex >> (),
+                          new Middle_placement<contraction::Edge_profile < Complex >> (),
+                          contraction::make_link_valid_contraction<Profile>(),
+                          contraction::make_remove_popable_blockers_visitor<Profile>());
+    contractor.contract_edges(num_contractions);
+  }
+};
+
+#endif  // UTILS_EDGE_CONTRACTOR_H_