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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):       Siargey Kachanovich
+ *
+ *    Copyright (C) 2015 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+#ifndef GENERATORS_H_
+#define GENERATORS_H_
+
+#include <CGAL/Epick_d.h>
+#include <CGAL/point_generators_d.h>
+#include <CGAL/Random.h>
+
+#include <fstream>
+#include <string>
+#include <vector>
+#include <cmath>
+
+using K = CGAL::Epick_d<CGAL::Dynamic_dimension_tag>;
+using FT = K::FT;
+using Point_d = K::Point_d;
+using Point_Vector = std::vector<Point_d>;
+using Random_cube_iterator = CGAL::Random_points_in_cube_d<Point_d>;
+using Random_point_iterator = CGAL::Random_points_in_ball_d<Point_d>;
+
+/**
+ * \brief Rock age method of reading off file
+ *
+ */
+inline void
+off_reader_cust(std::string file_name, std::vector<Point_d> & points) {
+  std::ifstream in_file(file_name.c_str(), std::ios::in);
+  if (!in_file.is_open()) {
+    std::cerr << "Unable to open file " << file_name << std::endl;
+    return;
+  }
+  std::string line;
+  double x;
+  // Line OFF. No need in it
+  if (!getline(in_file, line)) {
+    std::cerr << "No line OFF\n";
+    return;
+  }
+  // Line with 3 numbers. No need
+  if (!getline(in_file, line)) {
+    std::cerr << "No line with 3 numbers\n";
+    return;
+  }
+  // Reading points
+  while (getline(in_file, line)) {
+    std::vector< double > point;
+    std::istringstream iss(line);
+    while (iss >> x) {
+      point.push_back(x);
+    }
+    points.push_back(Point_d(point));
+  }
+  in_file.close();
+}
+
+/**
+ * \brief Customized version of read_points
+ * which takes into account a possible nbP first line
+ *
+ */
+inline void
+read_points_cust(std::string file_name, Point_Vector & points) {
+  std::ifstream in_file(file_name.c_str(), std::ios::in);
+  if (!in_file.is_open()) {
+    std::cerr << "Unable to open file " << file_name << std::endl;
+    return;
+  }
+  std::string line;
+  double x;
+  while (getline(in_file, line)) {
+    std::vector< double > point;
+    std::istringstream iss(line);
+    while (iss >> x) {
+      point.push_back(x);
+    }
+    Point_d p(point.begin(), point.end());
+    if (point.size() != 1)
+      points.push_back(p);
+  }
+  in_file.close();
+}
+
+/** \brief Generate points on a grid in a cube of side 2
+ * having {+-1}^D as vertices and insert them in W.
+ * The grid has "width" points on each side. 
+ * If torus is true then it is supposed that the cube represents
+ * a flat torus, hence the opposite borders are associated.
+ * The points on border in this case are not placed twice.
+ */
+void generate_points_grid(Point_Vector& W, int width, int D, bool torus) {
+  int nb_points = 1;
+  for (int i = 0; i < D; ++i)
+    nb_points *= width;
+  for (int i = 0; i < nb_points; ++i) {
+    std::vector<double> point;
+    int cell_i = i;
+    for (int l = 0; l < D; ++l) {
+      if (torus)
+        point.push_back(-1 + (2.0 / (width - 1))*(cell_i % width));
+      else
+        point.push_back(-1 + (2.0 / width)*(cell_i % width));
+      // attention: the bottom and the right are covered too!
+      cell_i /= width;
+    }
+    W.push_back(point);
+  }
+}
+
+/** \brief Generate nbP points uniformly in a cube of side 2
+ * having {+-1}^dim as its vertices and insert them in W.
+ */
+void generate_points_random_box(Point_Vector& W, int nbP, int dim) {
+  Random_cube_iterator rp(dim, 1.0);
+  for (int i = 0; i < nbP; i++) {
+    W.push_back(*rp++);
+  }
+}
+
+/** \brief Generate nbP points uniformly on a (dim-1)-sphere
+ *  and insert them in W.
+ */
+void generate_points_sphere(Point_Vector& W, int nbP, int dim) {
+  CGAL::Random_points_on_sphere_d<Point_d> rp(dim, 1);
+  for (int i = 0; i < nbP; i++)
+    W.push_back(*rp++);
+}
+
+/** \brief Generate nbP points on a (flat) d-torus embedded in R^{2d}
+ *
+ */
+void generate_points_torus(Point_Vector& W, int nbP, int dim) {
+  CGAL::Random rand;
+  const double pi = std::acos(-1);
+  for (int i = 0; i < nbP; i++) {
+    std::vector<FT> point;
+    for (int j = 0; j < dim; j++) {
+      double alpha = rand.uniform_real(static_cast<double>(0), 2*pi);
+      point.push_back(sin(alpha));
+      point.push_back(cos(alpha));
+    }
+    W.push_back(Point_d(point));
+  }
+}
+
+#endif  // GENERATORS_H_