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diff --git a/src/Persistence_representations/include/gudhi/Betti_sequence.h b/src/Persistence_representations/include/gudhi/Betti_sequence.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):       Mathieu Carriere
+ *
+ *    Copyright (C) 2018  INRIA (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 BETTI_SEQUENCE_H_
+#define BETTI_SEQUENCE_H_
+
+// gudhi include
+#include <gudhi/read_persistence_from_file.h>
+#include <gudhi/common_persistence_representations.h>
+#include <gudhi/Debug_utils.h>
+
+// standard include
+#include <cmath>
+#include <iostream>
+#include <vector>
+#include <limits>
+#include <fstream>
+#include <sstream>
+#include <algorithm>
+#include <string>
+#include <utility>
+#include <functional>
+
+namespace Gudhi {
+namespace Persistence_representations {
+
+/**
+ * \class Betti_sequence gudhi/Betti_sequence.h
+ * \brief A class implementing Betti sequences
+ *
+ * \ingroup Persistence_representations
+ *
+ * \details
+**/
+
+class Betti_sequence {
+
+  protected:
+   Persistence_diagram diagram;
+   int res_x, nb_cv;
+   double min_x, max_x;
+
+  public:
+
+   /** \brief Betti_sequence constructor.
+    * \ingroup Betti_sequence
+    *
+    * @param[in] _diagram    persistence diagram.
+    * @param[in] _min_x      minimum value of samples.
+    * @param[in] _max_x      maximum value of samples.
+    * @param[in] _res_x      number of samples.
+    *
+    */
+   Betti_sequence(const Persistence_diagram & _diagram, double _min_x = 0.0, double _max_x = 1.0, int _res_x = 10){diagram = _diagram; min_x = _min_x; max_x = _max_x; res_x = _res_x;}
+
+   /** \brief Computes the Betti sequences of a diagram.
+    * \ingroup Betti_sequence
+    *
+    */
+   std::vector<int> vectorize() const {
+     int num_pts = diagram.size(); double step = (max_x - min_x)/(res_x - 1);
+     std::vector<int> bs(res_x); for(int i = 0; i < res_x; i++)  bs[i] = 0;
+     for(int j = 0; j < num_pts; j++){
+       double px = diagram[j].first; double py = diagram[j].second;
+       int first = std::ceil((px-min_x)/step); int last = std::ceil((py-min_x)/step);
+       for(int i = first; i < last; i++)  bs[i] += 1;
+     }
+
+     return bs;
+   }
+
+}; // class Betti_sequence
+}  // namespace Persistence_representations
+}  // namespace Gudhi
+
+#endif  // BETTI_SEQUENCE_H_