1 files changed, 56 insertions, 0 deletions
diff --git a/src/Alpha_complex/example/Alpha_complex_from_points.cpp b/src/Alpha_complex/example/Alpha_complex_from_points.cpp
new file mode 100644
index 00000000..b160d702
--- /dev/null
+++ b/src/Alpha_complex/example/Alpha_complex_from_points.cpp
@@ -0,0 +1,56 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <CGAL/Delaunay_triangulation.h>
+#include <CGAL/Epick_d.h>
+
+#include <string>
+#include <vector>
+
+// to construct a Delaunay_triangulation from a OFF file
+#include "gudhi/Delaunay_triangulation_off_io.h"
+#include "gudhi/Alpha_complex.h"
+
+typedef CGAL::Epick_d< CGAL::Dynamic_dimension_tag > Kernel;
+typedef Kernel::Point_d Point;
+typedef std::vector<Point> Vector_of_points;
+
+int main(int argc, char **argv) {
+  // ----------------------------------------------------------------------------
+  // Init of a list of points
+  // ----------------------------------------------------------------------------
+  Vector_of_points points;
+
+  std::vector<double> coords = { 0.0, 0.0, 0.0, 1.0 };
+  points.push_back(Point(coords.begin(), coords.end()));
+  coords = { 0.0, 0.0, 1.0, 0.0 };
+  points.push_back(Point(coords.begin(), coords.end()));
+  coords = { 0.0, 1.0, 0.0, 0.0 };
+  points.push_back(Point(coords.begin(), coords.end()));
+  coords = { 1.0, 0.0, 0.0, 0.0 };
+  points.push_back(Point(coords.begin(), coords.end()));
+
+  // ----------------------------------------------------------------------------
+  // Init of an alpha complex from the list of points
+  // ----------------------------------------------------------------------------
+  double max_alpha_square_value = 1e10;
+  Gudhi::alphacomplex::Alpha_complex<Kernel> alpha_complex_from_points(3, points.size(), points.begin(), points.end(),
+                                                                       max_alpha_square_value);
+
+  // ----------------------------------------------------------------------------
+  // Display information about the alpha complex
+  // ----------------------------------------------------------------------------
+  std::cout << "Alpha complex is of dimension " << alpha_complex_from_points.dimension() <<
+      " - " << alpha_complex_from_points.num_simplices() << " simplices - " <<
+      alpha_complex_from_points.num_vertices() << " vertices." << std::endl;
+
+  std::cout << "Iterator on alpha complex simplices in the filtration order, with [filtration value]:" << std::endl;
+  for (auto f_simplex : alpha_complex_from_points.filtration_simplex_range()) {
+    std::cout << "   ( ";
+    for (auto vertex : alpha_complex_from_points.simplex_vertex_range(f_simplex)) {
+      std::cout << vertex << " ";
+    }
+    std::cout << ") -> " << "[" << alpha_complex_from_points.filtration(f_simplex) << "] ";
+    std::cout << std::endl;
+  }
+  return 0;
+}