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diff --git a/GudhUI/utils/Rips_builder.h b/GudhUI/utils/Rips_builder.h
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+/* This file is part of the Gudhi Library. The Gudhi library 
+ *    (Geometric Understanding in Higher Dimensions) is a generic C++ 
+ *    library for computational topology.
+ *
+ *    Author(s):       David Salinas
+ *
+ *    Copyright (C) 2014  INRIA Sophia Antipolis-Mediterranee (France)
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation, either version 3 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ * 
+ */
+
+#ifndef UTILS_RIPS_BUILDER_H_
+#define UTILS_RIPS_BUILDER_H_
+
+#include <boost/iterator/iterator_facade.hpp>
+
+#include <CGAL/Euclidean_distance.h>
+#include <CGAL/Orthogonal_k_neighbor_search.h>
+#include <CGAL/Search_traits_d.h>
+
+#include "utils/UI_utils.h"
+#include "model/Complex_typedefs.h"
+
+template<typename SkBlComplex> class Rips_builder {
+ private:
+  SkBlComplex& complex_;
+
+ public:
+  /**
+   * @brief Modify complex to be the Rips complex
+   * of its points with offset alpha.
+   */
+  Rips_builder(SkBlComplex& complex, double alpha) : complex_(complex) {
+    complex.keep_only_vertices();
+    if (alpha <= 0) return;
+    compute_edges(alpha);
+  }
+
+ private:
+  double squared_eucl_distance(const Point& p1, const Point& p2) const {
+    return Geometry_trait::Squared_distance_d()(p1, p2);
+  }
+
+  void compute_edges(double alpha) {
+    auto vertices = complex_.vertex_range();
+    for (auto p = vertices.begin(); p != vertices.end(); ++p) {
+      std::cout << *p << " ";
+      std::cout.flush();
+      for (auto q = p; ++q != vertices.end(); /**/)
+        if (squared_eucl_distance(complex_.point(*p), complex_.point(*q)) < 4 * alpha * alpha)
+          complex_.add_edge(*p, *q);
+    }
+    std::cout << std::endl;
+  }
+};
+
+#endif  // UTILS_RIPS_BUILDER_H_