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diff --git a/trunk/src/common/include/gudhi/distance_functions.h b/trunk/src/common/include/gudhi/distance_functions.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):       Clément Maria
+ *
+ *    Copyright (C) 2014  INRIA
+ *
+ *    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 DISTANCE_FUNCTIONS_H_
+#define DISTANCE_FUNCTIONS_H_
+
+#include <cmath>  // for std::sqrt
+#include <type_traits>  // for std::decay
+#include <iterator>  // for std::begin, std::end
+
+namespace Gudhi {
+
+/** @file
+ * @brief Global distance functions
+ */
+
+/** @brief Compute the Euclidean distance between two Points given by a range of coordinates. The points are assumed to
+ * have the same dimension. */
+class Euclidean_distance {
+ public:
+  template< typename Point >
+  auto operator()(const Point& p1, const Point& p2) const -> typename std::decay<decltype(*std::begin(p1))>::type {
+    auto it1 = p1.begin();
+    auto it2 = p2.begin();
+    typename Point::value_type dist = 0.;
+    for (; it1 != p1.end(); ++it1, ++it2) {
+      typename Point::value_type tmp = (*it1) - (*it2);
+      dist += tmp*tmp;
+    }
+    return std::sqrt(dist);
+  }
+};
+
+}  // namespace Gudhi
+
+#endif  // DISTANCE_FUNCTIONS_H_