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diff --git a/src/Gudhi_stat/include/gudhi/permutation_test.h b/src/Gudhi_stat/include/gudhi/permutation_test.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):       Pawel Dlotko
+ *
+ *    Copyright (C) 2015  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 PERMUTATION_TEST_H
+#define PERMUTATION_TEST_H
+
+
+//concretizations
+#include <vector>
+#include <iostream>
+#include <cstdlib>
+#include <algorithm>
+#include <gudhi/read_persitence_from_file.h>
+
+
+namespace Gudhi 
+{
+namespace Gudhi_stat 
+{
+
+template <typename Representation_of_persistence>
+double permutation_test( const std::vector<Representation_of_persistence*>& data_1 , const std::vector<Representation_of_persistence*>& data_2 , size_t number_of_permutations , double exponent = 1 )
+{	
+	bool dbg = false;
+	try
+	{
+		Representation_of_persistence av_1;// = new Representation_of_persistence;		
+		av_1.compute_average( data_1 );						
+		Representation_of_persistence av_2;// = new Representation_of_persistence;			
+	    av_2.compute_average( data_2 );	
+	    double initial_distance = av_1.distance( av_2 , exponent );
+		
+		
+		double counter = 0;
+		
+		
+		//TODO -- TBB. QUestion, why it uses memory. Where is the leak??
+		for  ( size_t i = 0 ; i != number_of_permutations ; ++i )
+		{					
+			std::vector<Representation_of_persistence*> all_data;
+			all_data.insert(all_data.end() , data_1.begin() , data_1.end() );
+			all_data.insert(all_data.end() , data_2.begin() , data_2.end() );
+			std::random_shuffle( all_data.begin() , all_data.end() );
+			
+			std::vector<Representation_of_persistence*> first_part(&all_data[0],&all_data[data_1.size()]);
+			std::vector<Representation_of_persistence*> second_part(&all_data[data_1.size()],&all_data[all_data.size()]);
+		
+		
+			Representation_of_persistence av_1;// = new Representation_of_persistence;		
+			Representation_of_persistence av_2;// = new Representation_of_persistence;	
+				
+			av_1.compute_average( first_part );					
+			av_2.compute_average( second_part );			
+			double distance_after_permutations = av_1.distance( av_2 , exponent );			
+			//delete av_1;
+			//delete av_2;
+			if ( distance_after_permutations > initial_distance )++counter;
+			if ( dbg )
+			{
+				std::cerr << "Permutation number : " << i << std::endl;
+				std::cerr << "distance_after_permutations : " << distance_after_permutations << std::endl;
+				std::cerr << "initial_distance : " << initial_distance << std::endl;
+				std::cerr << "counter : " << counter << std::endl;
+			}			
+		}
+		return counter / (double)number_of_permutations;
+	}
+	catch (...)
+	{
+		std::cout << "The data structure do not support the operations that are neccessay for a permutation test (averaging, distances) \n";
+	}
+	return 0;
+}//permutation_test
+
+}//Gudhi_stat
+}//Gudhi
+
+#endif