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-rw-r--r--src/Alpha_complex/doc/Intro_alpha_complex.h168
-rw-r--r--src/Alpha_complex/doc/alpha_complex_doc.ipe595
-rw-r--r--src/Alpha_complex/doc/alpha_complex_doc.pngbin0 -> 25554 bytes
-rw-r--r--src/Alpha_complex/doc/alpha_complex_doc_420.ipe514
-rw-r--r--src/Alpha_complex/doc/alpha_complex_doc_420.pngbin0 -> 80794 bytes
-rw-r--r--src/Alpha_complex/doc/alpha_complex_representation.ipe321
-rw-r--r--src/Alpha_complex/doc/alpha_complex_representation.pngbin0 -> 14606 bytes
-rw-r--r--src/Alpha_complex/example/Alpha_complex_from_off.cpp56
-rw-r--r--src/Alpha_complex/example/Alpha_complex_from_points.cpp62
-rw-r--r--src/Alpha_complex/example/CMakeLists.txt43
-rw-r--r--src/Alpha_complex/example/alphaoffreader_for_doc_32.txt22
-rw-r--r--src/Alpha_complex/example/alphaoffreader_for_doc_60.txt27
-rw-r--r--src/Alpha_complex/include/gudhi/Alpha_complex.h415
-rw-r--r--src/Alpha_complex/test/Alpha_complex_unit_test.cpp243
-rw-r--r--src/Alpha_complex/test/CMakeLists.txt45
-rw-r--r--src/Alpha_complex/test/README12
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diff --git a/src/Alpha_complex/doc/Intro_alpha_complex.h b/src/Alpha_complex/doc/Intro_alpha_complex.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): Vincent Rouvreau
+ *
+ * Copyright (C) 2015 INRIA Saclay (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 DOC_ALPHA_COMPLEX_INTRO_ALPHA_COMPLEX_H_
+#define DOC_ALPHA_COMPLEX_INTRO_ALPHA_COMPLEX_H_
+
+// needs namespace for Doxygen to link on classes
+namespace Gudhi {
+// needs namespace for Doxygen to link on classes
+namespace alphacomplex {
+
+/** \defgroup alpha_complex Alpha complex
+ *
+ * \author Vincent Rouvreau
+ *
+ * @{
+ *
+ * \section definition Definition
+ *
+ * Alpha_complex is a <a target="_blank" href="https://en.wikipedia.org/wiki/Simplicial_complex">simplicial complex</a>
+ * constructed from the finite cells of a Delaunay Triangulation.
+ *
+ * The filtration value of each simplex is computed as the square of the circumradius of the simplex if the circumsphere is empty (the simplex is then said to be Gabriel), and as the minimum of the filtration
+ * values of the codimension 1 cofaces that make it not Gabriel otherwise.
+ *
+ * All simplices that have a filtration value strictly greater than a given alpha squared value are not inserted into
+ * the complex.
+ *
+ * \image html "alpha_complex_representation.png" "Alpha-complex representation"
+ *
+ * Alpha_complex is constructing a `Simplex_tree` using <a target="_blank"
+ * href="http://doc.cgal.org/latest/Triangulation/index.html#Chapter_Triangulations">Delaunay Triangulation</a>
+ * \cite cgal:hdj-t-15b from <a target="_blank" href="http://www.cgal.org/">CGAL</a> (the Computational Geometry
+ * Algorithms Library \cite cgal:eb-15b).
+ *
+ * The complex is a template class requiring an Epick_d <a target="_blank"
+ * href="http://doc.cgal.org/latest/Kernel_d/index.html#Chapter_dD_Geometry_Kernel">dD Geometry Kernel</a>
+ * \cite cgal:s-gkd-15b from CGAL as template parameter.
+ *
+ * \remark When Alpha_complex is constructed with an infinite value of alpha, the complex is a Delaunay complex.
+ *
+ * \section pointsexample Example from points
+ *
+ * This example builds the Delaunay triangulation from the given points in a 2D static kernel, and initializes the
+ * alpha complex with it.
+ *
+ * Then, it is asked to display information about the alpha complex.
+ *
+ * \include Alpha_complex/Alpha_complex_from_points.cpp
+ *
+ * When launching:
+ *
+ * \code $> ./alphapoints
+ * \endcode
+ *
+ * the program output is:
+ *
+ * \include Alpha_complex/alphaoffreader_for_doc_60.txt
+ *
+ * \section algorithm Algorithm
+ *
+ * \subsection datastructure Data structure
+ *
+ * In order to build the alpha complex, first, a Simplex tree is built from the cells of a Delaunay Triangulation.
+ * (The filtration value is set to NaN, which stands for unknown value):
+ * \image html "alpha_complex_doc.png" "Simplex tree structure construction example"
+ *
+ * \subsection filtrationcomputation Filtration value computation algorithm
+ *
+ * \f{algorithm}{
+ * \caption{Filtration value computation algorithm}\label{alpha}
+ * \begin{algorithmic}
+ * \For{i : dimension $\rightarrow$ 0}
+ * \ForAll{$\sigma$ of dimension i}
+ * \If {filtration($\sigma$) is NaN}
+ * \State filtration($\sigma$) = $\alpha^2(\sigma)$
+ * \EndIf
+ * \ForAll{$\tau$ face of $\sigma$} \Comment{propagate alpha filtration value}
+ * \If {filtration($\tau$) is not NaN}
+ * \State filtration($\tau$) = min (filtration($\tau$), filtration($\sigma$))
+ * \Else
+ * \If {$\tau$ is not Gabriel for $\sigma$}
+ * \State filtration($\tau$) = filtration($\sigma$)
+ * \EndIf
+ * \EndIf
+ * \EndFor
+ * \EndFor
+ * \EndFor
+ * \State make\_filtration\_non\_decreasing()
+ * \State prune\_above\_filtration()
+ * \end{algorithmic}
+ * \f}
+ *
+ * \subsubsection dimension2 Dimension 2
+ *
+ * From the example above, it means the algorithm looks into each triangle ([0,1,2], [0,2,4], [1,2,3], ...),
+ * computes the filtration value of the triangle, and then propagates the filtration value as described
+ * here :
+ * \image html "alpha_complex_doc_420.png" "Filtration value propagation example"
+ *
+ * \subsubsection dimension1 Dimension 1
+ *
+ * Then, the algorithm looks into each edge ([0,1], [0,2], [1,2], ...),
+ * computes the filtration value of the edge (in this case, propagation will have no effect).
+ *
+ * \subsubsection dimension0 Dimension 0
+ *
+ * Finally, the algorithm looks into each vertex ([0], [1], [2], [3], [4], [5] and [6]) and
+ * sets the filtration value (0 in case of a vertex - propagation will have no effect).
+ *
+ * \subsubsection nondecreasing Non decreasing filtration values
+ *
+ * As the squared radii computed by CGAL are an approximation, it might happen that these alpha squared values do not quite define a proper filtration (i.e. non-decreasing with respect to inclusion).
+ * We fix that up by calling `Simplex_tree::make_filtration_non_decreasing()`.
+ *
+ * \subsubsection pruneabove Prune above given filtration value
+ *
+ * The simplex tree is pruned from the given maximum alpha squared value (cf. `Simplex_tree::prune_above_filtration()`).
+ * In the following example, the value is given by the user as argument of the program.
+ *
+ *
+ * \section offexample Example from OFF file
+ *
+ * This example builds the Delaunay triangulation in a dynamic kernel, and initializes the alpha complex with it.
+ *
+ *
+ * Then, it is asked to display information about the alpha complex.
+ *
+ * \include Alpha_complex/Alpha_complex_from_off.cpp
+ *
+ * When launching:
+ *
+ * \code $> ./alphaoffreader ../../data/points/alphacomplexdoc.off 32.0
+ * \endcode
+ *
+ * the program output is:
+ *
+ * \include Alpha_complex/alphaoffreader_for_doc_32.txt
+ *
+ * \copyright GNU General Public License v3.
+ * \verbatim Contact: gudhi-users@lists.gforge.inria.fr \endverbatim
+ */
+/** @} */ // end defgroup alpha_complex
+
+} // namespace alphacomplex
+
+} // namespace Gudhi
+
+#endif // DOC_ALPHA_COMPLEX_INTRO_ALPHA_COMPLEX_H_
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diff --git a/src/Alpha_complex/doc/alpha_complex_representation.png b/src/Alpha_complex/doc/alpha_complex_representation.png
new file mode 100644
index 00000000..7b81cd69
--- /dev/null
+++ b/src/Alpha_complex/doc/alpha_complex_representation.png
Binary files differ
diff --git a/src/Alpha_complex/example/Alpha_complex_from_off.cpp b/src/Alpha_complex/example/Alpha_complex_from_off.cpp
new file mode 100644
index 00000000..963ef5ca
--- /dev/null
+++ b/src/Alpha_complex/example/Alpha_complex_from_off.cpp
@@ -0,0 +1,56 @@
+#include <gudhi/Alpha_complex.h>
+#include <CGAL/Epick_d.h>
+
+#include <iostream>
+#include <string>
+
+void usage(int nbArgs, char * const progName) {
+ std::cerr << "Error: Number of arguments (" << nbArgs << ") is not correct\n";
+ std::cerr << "Usage: " << progName << " filename.off alpha_square_max_value [ouput_file.txt]\n";
+ std::cerr << " i.e.: " << progName << " ../../data/points/alphacomplexdoc.off 60.0\n";
+ exit(-1); // ----- >>
+}
+
+int main(int argc, char **argv) {
+ if ((argc != 3) && (argc != 4)) usage(argc, (argv[0] - 1));
+
+ std::string off_file_name(argv[1]);
+ double alpha_square_max_value = atof(argv[2]);
+
+ // ----------------------------------------------------------------------------
+ // Init of an alpha complex from an OFF file
+ // ----------------------------------------------------------------------------
+ typedef CGAL::Epick_d< CGAL::Dynamic_dimension_tag > Kernel;
+ Gudhi::alphacomplex::Alpha_complex<Kernel> alpha_complex_from_file(off_file_name, alpha_square_max_value);
+
+ std::streambuf* streambufffer;
+ std::ofstream ouput_file_stream;
+
+ if (argc == 4) {
+ ouput_file_stream.open(std::string(argv[3]));
+ streambufffer = ouput_file_stream.rdbuf();
+ } else {
+ streambufffer = std::cout.rdbuf();
+ }
+
+ std::ostream output_stream(streambufffer);
+
+ // ----------------------------------------------------------------------------
+ // Display information about the alpha complex
+ // ----------------------------------------------------------------------------
+ output_stream << "Alpha complex is of dimension " << alpha_complex_from_file.dimension() <<
+ " - " << alpha_complex_from_file.num_simplices() << " simplices - " <<
+ alpha_complex_from_file.num_vertices() << " vertices." << std::endl;
+
+ output_stream << "Iterator on alpha complex simplices in the filtration order, with [filtration value]:" << std::endl;
+ for (auto f_simplex : alpha_complex_from_file.filtration_simplex_range()) {
+ output_stream << " ( ";
+ for (auto vertex : alpha_complex_from_file.simplex_vertex_range(f_simplex)) {
+ output_stream << vertex << " ";
+ }
+ output_stream << ") -> " << "[" << alpha_complex_from_file.filtration(f_simplex) << "] ";
+ output_stream << std::endl;
+ }
+ ouput_file_stream.close();
+ return 0;
+}
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..cd17af1e
--- /dev/null
+++ b/src/Alpha_complex/example/Alpha_complex_from_points.cpp
@@ -0,0 +1,62 @@
+#include <CGAL/Epick_d.h>
+#include <gudhi/Alpha_complex.h>
+
+#include <iostream>
+#include <string>
+#include <vector>
+#include <limits> // for numeric limits
+
+typedef CGAL::Epick_d< CGAL::Dimension_tag<2> > Kernel;
+typedef Kernel::Point_d Point;
+typedef std::vector<Point> Vector_of_points;
+
+void usage(int nbArgs, char * const progName) {
+ std::cerr << "Error: Number of arguments (" << nbArgs << ") is not correct\n";
+ std::cerr << "Usage: " << progName << " [alpha_square_max_value]\n";
+ std::cerr << " i.e.: " << progName << " 60.0\n";
+ exit(-1); // ----- >>
+}
+
+int main(int argc, char **argv) {
+ if ((argc != 1) && (argc != 2)) usage(argc, (argv[0] - 1));
+
+ // Delaunay complex if alpha_square_max_value is not given by the user.
+ double alpha_square_max_value = std::numeric_limits<double>::infinity();
+ if (argc == 2)
+ alpha_square_max_value = atof(argv[1]);
+
+ // ----------------------------------------------------------------------------
+ // Init of a list of points
+ // ----------------------------------------------------------------------------
+ Vector_of_points points;
+ points.push_back(Point(1.0, 1.0));
+ points.push_back(Point(7.0, 0.0));
+ points.push_back(Point(4.0, 6.0));
+ points.push_back(Point(9.0, 6.0));
+ points.push_back(Point(0.0, 14.0));
+ points.push_back(Point(2.0, 19.0));
+ points.push_back(Point(9.0, 17.0));
+
+ // ----------------------------------------------------------------------------
+ // Init of an alpha complex from the list of points
+ // ----------------------------------------------------------------------------
+ Gudhi::alphacomplex::Alpha_complex<Kernel> alpha_complex_from_points(points, alpha_square_max_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;
+}
diff --git a/src/Alpha_complex/example/CMakeLists.txt b/src/Alpha_complex/example/CMakeLists.txt
new file mode 100644
index 00000000..f1346867
--- /dev/null
+++ b/src/Alpha_complex/example/CMakeLists.txt
@@ -0,0 +1,43 @@
+cmake_minimum_required(VERSION 2.6)
+project(GUDHIAlphaShapesExample)
+
+# need CGAL 4.7
+# cmake -DCGAL_DIR=~/workspace/CGAL-4.7-Ic-41 ../../..
+if(CGAL_FOUND)
+ if (NOT CGAL_VERSION VERSION_LESS 4.7.0)
+ message(STATUS "CGAL version: ${CGAL_VERSION}.")
+
+ find_package(Eigen3 3.1.0)
+ if (EIGEN3_FOUND)
+ message(STATUS "Eigen3 version: ${EIGEN3_VERSION}.")
+ include( ${EIGEN3_USE_FILE} )
+
+ add_executable ( alphapoints Alpha_complex_from_points.cpp )
+ target_link_libraries(alphapoints ${Boost_SYSTEM_LIBRARY} ${CGAL_LIBRARY})
+ add_executable ( alphaoffreader Alpha_complex_from_off.cpp )
+ target_link_libraries(alphaoffreader ${Boost_SYSTEM_LIBRARY} ${CGAL_LIBRARY})
+ if (TBB_FOUND)
+ target_link_libraries(alphapoints ${TBB_RELEASE_LIBRARY})
+ target_link_libraries(alphaoffreader ${TBB_RELEASE_LIBRARY})
+ endif()
+
+ add_test(alphapoints ${CMAKE_CURRENT_BINARY_DIR}/alphapoints)
+ # Do not forget to copy test files in current binary dir
+ file(COPY "${CMAKE_SOURCE_DIR}/data/points/alphacomplexdoc.off" DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/)
+ add_test(alphaoffreader_doc_60 ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader alphacomplexdoc.off 60.0 ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_result_60.txt)
+ add_test(alphaoffreader_doc_32 ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader alphacomplexdoc.off 32.0 ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_result_32.txt)
+ if (DIFF_PATH)
+ # Do not forget to copy test results files in current binary dir
+ file(COPY "alphaoffreader_for_doc_32.txt" DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/)
+ file(COPY "alphaoffreader_for_doc_60.txt" DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/)
+
+ add_test(alphaoffreader_doc_60_diff_files ${DIFF_PATH} ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_result_60.txt ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_for_doc_60.txt)
+ add_test(alphaoffreader_doc_32_diff_files ${DIFF_PATH} ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_result_32.txt ${CMAKE_CURRENT_BINARY_DIR}/alphaoffreader_for_doc_32.txt)
+ endif()
+ else()
+ message(WARNING "Eigen3 not found. Version 3.1.0 is required for Alpha shapes feature.")
+ endif()
+ else()
+ message(WARNING "CGAL version: ${CGAL_VERSION} is too old to compile Alpha shapes feature. Version 4.6.0 is required.")
+ endif ()
+endif()
diff --git a/src/Alpha_complex/example/alphaoffreader_for_doc_32.txt b/src/Alpha_complex/example/alphaoffreader_for_doc_32.txt
new file mode 100644
index 00000000..13183e86
--- /dev/null
+++ b/src/Alpha_complex/example/alphaoffreader_for_doc_32.txt
@@ -0,0 +1,22 @@
+Alpha complex is of dimension 2 - 20 simplices - 7 vertices.
+Iterator on alpha complex simplices in the filtration order, with [filtration value]:
+ ( 0 ) -> [0]
+ ( 1 ) -> [0]
+ ( 2 ) -> [0]
+ ( 3 ) -> [0]
+ ( 4 ) -> [0]
+ ( 5 ) -> [0]
+ ( 6 ) -> [0]
+ ( 3 2 ) -> [6.25]
+ ( 5 4 ) -> [7.25]
+ ( 2 0 ) -> [8.5]
+ ( 1 0 ) -> [9.25]
+ ( 3 1 ) -> [10]
+ ( 2 1 ) -> [11.25]
+ ( 3 2 1 ) -> [12.5]
+ ( 2 1 0 ) -> [12.9959]
+ ( 6 5 ) -> [13.25]
+ ( 4 2 ) -> [20]
+ ( 6 4 ) -> [22.7367]
+ ( 6 5 4 ) -> [22.7367]
+ ( 6 3 ) -> [30.25]
diff --git a/src/Alpha_complex/example/alphaoffreader_for_doc_60.txt b/src/Alpha_complex/example/alphaoffreader_for_doc_60.txt
new file mode 100644
index 00000000..71f29a00
--- /dev/null
+++ b/src/Alpha_complex/example/alphaoffreader_for_doc_60.txt
@@ -0,0 +1,27 @@
+Alpha complex is of dimension 2 - 25 simplices - 7 vertices.
+Iterator on alpha complex simplices in the filtration order, with [filtration value]:
+ ( 0 ) -> [0]
+ ( 1 ) -> [0]
+ ( 2 ) -> [0]
+ ( 3 ) -> [0]
+ ( 4 ) -> [0]
+ ( 5 ) -> [0]
+ ( 6 ) -> [0]
+ ( 3 2 ) -> [6.25]
+ ( 5 4 ) -> [7.25]
+ ( 2 0 ) -> [8.5]
+ ( 1 0 ) -> [9.25]
+ ( 3 1 ) -> [10]
+ ( 2 1 ) -> [11.25]
+ ( 3 2 1 ) -> [12.5]
+ ( 2 1 0 ) -> [12.9959]
+ ( 6 5 ) -> [13.25]
+ ( 4 2 ) -> [20]
+ ( 6 4 ) -> [22.7367]
+ ( 6 5 4 ) -> [22.7367]
+ ( 6 3 ) -> [30.25]
+ ( 6 2 ) -> [36.5]
+ ( 6 3 2 ) -> [36.5]
+ ( 6 4 2 ) -> [37.2449]
+ ( 4 0 ) -> [59.7107]
+ ( 4 2 0 ) -> [59.7107]
diff --git a/src/Alpha_complex/include/gudhi/Alpha_complex.h b/src/Alpha_complex/include/gudhi/Alpha_complex.h
new file mode 100644
index 00000000..ca2b68ca
--- /dev/null
+++ b/src/Alpha_complex/include/gudhi/Alpha_complex.h
@@ -0,0 +1,415 @@
+/* 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): Vincent Rouvreau
+ *
+ * Copyright (C) 2015 INRIA Saclay (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 ALPHA_COMPLEX_H_
+#define ALPHA_COMPLEX_H_
+
+// to construct a simplex_tree from Delaunay_triangulation
+#include <gudhi/graph_simplicial_complex.h>
+#include <gudhi/Simplex_tree.h>
+#include <gudhi/Debug_utils.h>
+// to construct Alpha_complex from a OFF file of points
+#include <gudhi/Points_off_io.h>
+
+#include <stdlib.h>
+#include <math.h> // isnan, fmax
+
+#include <CGAL/Delaunay_triangulation.h>
+#include <CGAL/Epick_d.h>
+#include <CGAL/Spatial_sort_traits_adapter_d.h>
+
+#include <iostream>
+#include <vector>
+#include <string>
+#include <limits> // NaN
+#include <map>
+#include <utility> // std::pair
+#include <stdexcept>
+#include <numeric> // for std::iota
+
+namespace Gudhi {
+
+namespace alphacomplex {
+
+/**
+ * \class Alpha_complex Alpha_complex.h gudhi/Alpha_complex.h
+ * \brief Alpha complex data structure.
+ *
+ * \ingroup alpha_complex
+ *
+ * \details
+ * The data structure can be constructed from a CGAL Delaunay triangulation (for more informations on CGAL Delaunay
+ * triangulation, please refer to the corresponding chapter in page http://doc.cgal.org/latest/Triangulation/) or from
+ * an OFF file (cf. Points_off_reader).
+ *
+ * Please refer to \ref alpha_complex for examples.
+ *
+ * The complex is a template class requiring an Epick_d <a target="_blank"
+ * href="http://doc.cgal.org/latest/Kernel_d/index.html#Chapter_dD_Geometry_Kernel">dD Geometry Kernel</a>
+ * \cite cgal:s-gkd-15b from CGAL as template, default value is <a target="_blank"
+ * href="http://doc.cgal.org/latest/Kernel_d/classCGAL_1_1Epick__d.html">CGAL::Epick_d</a>
+ * < <a target="_blank" href="http://doc.cgal.org/latest/Kernel_23/classCGAL_1_1Dynamic__dimension__tag.html">
+ * CGAL::Dynamic_dimension_tag </a> >
+ *
+ * \remark When Alpha_complex is constructed with an infinite value of alpha, the complex is a Delaunay complex.
+ *
+ */
+template<class Kernel = CGAL::Epick_d<CGAL::Dynamic_dimension_tag>>
+class Alpha_complex : public Simplex_tree<> {
+ public:
+ // Add an int in TDS to save point index in the structure
+ typedef CGAL::Triangulation_data_structure<CGAL::Dynamic_dimension_tag,
+ CGAL::Triangulation_vertex<Kernel, std::ptrdiff_t>,
+ CGAL::Triangulation_full_cell<Kernel> > TDS;
+ /** \brief A Delaunay triangulation of a set of points in \f$ \mathbb{R}^D\f$.*/
+ typedef CGAL::Delaunay_triangulation<Kernel, TDS> Delaunay_triangulation;
+
+ /** \brief A point in Euclidean space.*/
+ typedef typename Kernel::Point_d Point_d;
+ /** \brief Geometric traits class that provides the geometric types and predicates needed by Delaunay
+ * triangulations.*/
+ typedef Kernel Geom_traits;
+
+ private:
+ // From Simplex_tree
+ // Type required to insert into a simplex_tree (with or without subfaces).
+ typedef std::vector<Vertex_handle> Vector_vertex;
+
+ // Simplex_result is the type returned from simplex_tree insert function.
+ typedef typename std::pair<Simplex_handle, bool> Simplex_result;
+
+ typedef typename Kernel::Compute_squared_radius_d Squared_Radius;
+ typedef typename Kernel::Side_of_bounded_sphere_d Is_Gabriel;
+ typedef typename Kernel::Point_dimension_d Point_Dimension;
+
+ // Type required to compute squared radius, or side of bounded sphere on a vector of points.
+ typedef typename std::vector<Point_d> Vector_of_CGAL_points;
+
+ // Vertex_iterator type from CGAL.
+ typedef typename Delaunay_triangulation::Vertex_iterator CGAL_vertex_iterator;
+
+ // size_type type from CGAL.
+ typedef typename Delaunay_triangulation::size_type size_type;
+
+ // Map type to switch from simplex tree vertex handle to CGAL vertex iterator.
+ typedef typename std::map< Vertex_handle, CGAL_vertex_iterator > Vector_vertex_iterator;
+
+ private:
+ /** \brief Vertex iterator vector to switch from simplex tree vertex handle to CGAL vertex iterator.
+ * Vertex handles are inserted sequentially, starting at 0.*/
+ Vector_vertex_iterator vertex_handle_to_iterator_;
+ /** \brief Pointer on the CGAL Delaunay triangulation.*/
+ Delaunay_triangulation* triangulation_;
+ /** \brief Kernel for triangulation_ functions access.*/
+ Kernel kernel_;
+
+ public:
+ /** \brief Alpha_complex constructor from an OFF file name.
+ * Uses the Delaunay_triangulation_off_reader to construct the Delaunay triangulation required to initialize
+ * the Alpha_complex.
+ *
+ * Duplicate points are inserted once in the Alpha_complex. This is the reason why the vertices may be not contiguous.
+ *
+ * @param[in] off_file_name OFF file [path and] name.
+ * @param[in] max_alpha_square maximum for alpha square value. Default value is +\f$\infty\f$.
+ */
+ Alpha_complex(const std::string& off_file_name,
+ Filtration_value max_alpha_square = std::numeric_limits<Filtration_value>::infinity())
+ : triangulation_(nullptr) {
+ Gudhi::Points_off_reader<Point_d> off_reader(off_file_name);
+ if (!off_reader.is_valid()) {
+ std::cerr << "Alpha_complex - Unable to read file " << off_file_name << "\n";
+ exit(-1); // ----- >>
+ }
+
+ init_from_range(off_reader.get_point_cloud(), max_alpha_square);
+ }
+
+ /** \brief Alpha_complex constructor from a list of points.
+ *
+ * Duplicate points are inserted once in the Alpha_complex. This is the reason why the vertices may be not contiguous.
+ *
+ * @param[in] points Range of points to triangulate. Points must be in Kernel::Point_d
+ * @param[in] max_alpha_square maximum for alpha square value. Default value is +\f$\infty\f$.
+ *
+ * The type InputPointRange must be a range for which std::begin and
+ * std::end return input iterators on a Kernel::Point_d.
+ *
+ * @post Compare num_simplices with InputPointRange points number (not the same in case of duplicate points).
+ */
+ template<typename InputPointRange >
+ Alpha_complex(const InputPointRange& points,
+ Filtration_value max_alpha_square = std::numeric_limits<Filtration_value>::infinity())
+ : triangulation_(nullptr) {
+ init_from_range(points, max_alpha_square);
+ }
+
+ /** \brief Alpha_complex destructor.
+ *
+ * @warning Deletes the Delaunay triangulation.
+ */
+ ~Alpha_complex() {
+ delete triangulation_;
+ }
+
+ // Forbid copy/move constructor/assignment operator
+ Alpha_complex(const Alpha_complex& other) = delete;
+ Alpha_complex& operator= (const Alpha_complex& other) = delete;
+ Alpha_complex (Alpha_complex&& other) = delete;
+ Alpha_complex& operator= (Alpha_complex&& other) = delete;
+
+ /** \brief get_point returns the point corresponding to the vertex given as parameter.
+ *
+ * @param[in] vertex Vertex handle of the point to retrieve.
+ * @return The point found.
+ * @exception std::out_of_range In case vertex is not found (cf. std::vector::at).
+ */
+ Point_d get_point(Vertex_handle vertex) const {
+ return vertex_handle_to_iterator_.at(vertex)->point();
+ }
+
+ private:
+ template<typename InputPointRange >
+ void init_from_range(const InputPointRange& points, Filtration_value max_alpha_square) {
+ auto first = std::begin(points);
+ auto last = std::end(points);
+ if (first != last) {
+ // point_dimension function initialization
+ Point_Dimension point_dimension = kernel_.point_dimension_d_object();
+
+ // Delaunay triangulation is point dimension.
+ triangulation_ = new Delaunay_triangulation(point_dimension(*first));
+
+ std::vector<Point_d> points(first, last);
+
+ // Creates a vector {0, 1, ..., N-1}
+ std::vector<std::ptrdiff_t> indices(boost::counting_iterator<std::ptrdiff_t>(0),
+ boost::counting_iterator<std::ptrdiff_t>(points.size()));
+
+ // Sort indices considering CGAL spatial sort
+ typedef CGAL::Spatial_sort_traits_adapter_d<Kernel, Point_d*> Search_traits_d;
+ spatial_sort(indices.begin(), indices.end(), Search_traits_d(&(points[0])));
+
+ typename Delaunay_triangulation::Full_cell_handle hint;
+ for (auto index : indices) {
+ typename Delaunay_triangulation::Vertex_handle pos = triangulation_->insert(points[index], hint);
+ // Save index value as data to retrieve it after insertion
+ pos->data() = index;
+ hint = pos->full_cell();
+ }
+ init(max_alpha_square);
+ }
+ }
+
+ /** \brief Initialize the Alpha_complex from the Delaunay triangulation.
+ *
+ * @param[in] max_alpha_square maximum for alpha square value.
+ *
+ * @warning Delaunay triangulation must be already constructed with at least one vertex and dimension must be more
+ * than 0.
+ *
+ * Initialization can be launched once.
+ */
+ void init(Filtration_value max_alpha_square) {
+ if (triangulation_ == nullptr) {
+ std::cerr << "Alpha_complex init - Cannot init from a NULL triangulation\n";
+ return; // ----- >>
+ }
+ if (triangulation_->number_of_vertices() < 1) {
+ std::cerr << "Alpha_complex init - Cannot init from a triangulation without vertices\n";
+ return; // ----- >>
+ }
+ if (triangulation_->maximal_dimension() < 1) {
+ std::cerr << "Alpha_complex init - Cannot init from a zero-dimension triangulation\n";
+ return; // ----- >>
+ }
+ if (num_vertices() > 0) {
+ std::cerr << "Alpha_complex init - Cannot init twice\n";
+ return; // ----- >>
+ }
+
+ set_dimension(triangulation_->maximal_dimension());
+
+ // --------------------------------------------------------------------------------------------
+ // double map to retrieve simplex tree vertex handles from CGAL vertex iterator and vice versa
+ // Loop on triangulation vertices list
+ for (CGAL_vertex_iterator vit = triangulation_->vertices_begin(); vit != triangulation_->vertices_end(); ++vit) {
+ if (!triangulation_->is_infinite(*vit)) {
+#ifdef DEBUG_TRACES
+ std::cout << "Vertex insertion - " << vit->data() << " -> " << vit->point() << std::endl;
+#endif // DEBUG_TRACES
+ vertex_handle_to_iterator_.emplace(vit->data(), vit);
+ }
+ }
+ // --------------------------------------------------------------------------------------------
+
+ // --------------------------------------------------------------------------------------------
+ // Simplex_tree construction from loop on triangulation finite full cells list
+ for (auto cit = triangulation_->finite_full_cells_begin(); cit != triangulation_->finite_full_cells_end(); ++cit) {
+ Vector_vertex vertexVector;
+#ifdef DEBUG_TRACES
+ std::cout << "Simplex_tree insertion ";
+#endif // DEBUG_TRACES
+ for (auto vit = cit->vertices_begin(); vit != cit->vertices_end(); ++vit) {
+ if (*vit != nullptr) {
+#ifdef DEBUG_TRACES
+ std::cout << " " << (*vit)->data();
+#endif // DEBUG_TRACES
+ // Vector of vertex construction for simplex_tree structure
+ vertexVector.push_back((*vit)->data());
+ }
+ }
+#ifdef DEBUG_TRACES
+ std::cout << std::endl;
+#endif // DEBUG_TRACES
+ // Insert each simplex and its subfaces in the simplex tree - filtration is NaN
+ insert_simplex_and_subfaces(vertexVector, std::numeric_limits<double>::quiet_NaN());
+ }
+ // --------------------------------------------------------------------------------------------
+
+ // --------------------------------------------------------------------------------------------
+ // ### For i : d -> 0
+ for (int decr_dim = dimension(); decr_dim >= 0; decr_dim--) {
+ // ### Foreach Sigma of dim i
+ for (auto f_simplex : skeleton_simplex_range(decr_dim)) {
+ int f_simplex_dim = dimension(f_simplex);
+ if (decr_dim == f_simplex_dim) {
+ Vector_of_CGAL_points pointVector;
+#ifdef DEBUG_TRACES
+ std::cout << "Sigma of dim " << decr_dim << " is";
+#endif // DEBUG_TRACES
+ for (auto vertex : simplex_vertex_range(f_simplex)) {
+ pointVector.push_back(get_point(vertex));
+#ifdef DEBUG_TRACES
+ std::cout << " " << vertex;
+#endif // DEBUG_TRACES
+ }
+#ifdef DEBUG_TRACES
+ std::cout << std::endl;
+#endif // DEBUG_TRACES
+ // ### If filt(Sigma) is NaN : filt(Sigma) = alpha(Sigma)
+ if (isnan(filtration(f_simplex))) {
+ Filtration_value alpha_complex_filtration = 0.0;
+ // No need to compute squared_radius on a single point - alpha is 0.0
+ if (f_simplex_dim > 0) {
+ // squared_radius function initialization
+ Squared_Radius squared_radius = kernel_.compute_squared_radius_d_object();
+
+ alpha_complex_filtration = squared_radius(pointVector.begin(), pointVector.end());
+ }
+ assign_filtration(f_simplex, alpha_complex_filtration);
+#ifdef DEBUG_TRACES
+ std::cout << "filt(Sigma) is NaN : filt(Sigma) =" << filtration(f_simplex) << std::endl;
+#endif // DEBUG_TRACES
+ }
+ propagate_alpha_filtration(f_simplex, decr_dim);
+ }
+ }
+ }
+ // --------------------------------------------------------------------------------------------
+
+ // --------------------------------------------------------------------------------------------
+ // As Alpha value is an approximation, we have to make filtration non decreasing while increasing the dimension
+ bool modified_filt = make_filtration_non_decreasing();
+ // Remove all simplices that have a filtration value greater than max_alpha_square
+ // Remark: prune_above_filtration does not require initialize_filtration to be done before.
+ modified_filt |= prune_above_filtration(max_alpha_square);
+ if (modified_filt) {
+ initialize_filtration();
+ }
+ // --------------------------------------------------------------------------------------------
+ }
+
+ template<typename Simplex_handle>
+ void propagate_alpha_filtration(Simplex_handle f_simplex, int decr_dim) {
+ // ### Foreach Tau face of Sigma
+ for (auto f_boundary : boundary_simplex_range(f_simplex)) {
+#ifdef DEBUG_TRACES
+ std::cout << " | --------------------------------------------------\n";
+ std::cout << " | Tau ";
+ for (auto vertex : simplex_vertex_range(f_boundary)) {
+ std::cout << vertex << " ";
+ }
+ std::cout << "is a face of Sigma\n";
+ std::cout << " | isnan(filtration(Tau)=" << isnan(filtration(f_boundary)) << std::endl;
+#endif // DEBUG_TRACES
+ // ### If filt(Tau) is not NaN
+ if (!isnan(filtration(f_boundary))) {
+ // ### filt(Tau) = fmin(filt(Tau), filt(Sigma))
+ Filtration_value alpha_complex_filtration = fmin(filtration(f_boundary), filtration(f_simplex));
+ assign_filtration(f_boundary, alpha_complex_filtration);
+#ifdef DEBUG_TRACES
+ std::cout << " | filt(Tau) = fmin(filt(Tau), filt(Sigma)) = " << filtration(f_boundary) << std::endl;
+#endif // DEBUG_TRACES
+ // ### Else
+ } else {
+ // No need to compute is_gabriel for dimension <= 2
+ // i.e. : Sigma = (3,1) => Tau = 1
+ if (decr_dim > 1) {
+ // insert the Tau points in a vector for is_gabriel function
+ Vector_of_CGAL_points pointVector;
+#ifdef DEBUG_TRACES
+ Vertex_handle vertexForGabriel = Vertex_handle();
+#endif // DEBUG_TRACES
+ for (auto vertex : simplex_vertex_range(f_boundary)) {
+ pointVector.push_back(get_point(vertex));
+ }
+ // Retrieve the Sigma point that is not part of Tau - parameter for is_gabriel function
+ Point_d point_for_gabriel;
+ for (auto vertex : simplex_vertex_range(f_simplex)) {
+ point_for_gabriel = get_point(vertex);
+ if (std::find(pointVector.begin(), pointVector.end(), point_for_gabriel) == pointVector.end()) {
+#ifdef DEBUG_TRACES
+ // vertex is not found in Tau
+ vertexForGabriel = vertex;
+#endif // DEBUG_TRACES
+ // No need to continue loop
+ break;
+ }
+ }
+ // is_gabriel function initialization
+ Is_Gabriel is_gabriel = kernel_.side_of_bounded_sphere_d_object();
+ bool is_gab = is_gabriel(pointVector.begin(), pointVector.end(), point_for_gabriel)
+ != CGAL::ON_BOUNDED_SIDE;
+#ifdef DEBUG_TRACES
+ std::cout << " | Tau is_gabriel(Sigma)=" << is_gab << " - vertexForGabriel=" << vertexForGabriel << std::endl;
+#endif // DEBUG_TRACES
+ // ### If Tau is not Gabriel of Sigma
+ if (false == is_gab) {
+ // ### filt(Tau) = filt(Sigma)
+ Filtration_value alpha_complex_filtration = filtration(f_simplex);
+ assign_filtration(f_boundary, alpha_complex_filtration);
+#ifdef DEBUG_TRACES
+ std::cout << " | filt(Tau) = filt(Sigma) = " << filtration(f_boundary) << std::endl;
+#endif // DEBUG_TRACES
+ }
+ }
+ }
+ }
+ }
+};
+
+} // namespace alphacomplex
+
+} // namespace Gudhi
+
+#endif // ALPHA_COMPLEX_H_
diff --git a/src/Alpha_complex/test/Alpha_complex_unit_test.cpp b/src/Alpha_complex/test/Alpha_complex_unit_test.cpp
new file mode 100644
index 00000000..80b39924
--- /dev/null
+++ b/src/Alpha_complex/test/Alpha_complex_unit_test.cpp
@@ -0,0 +1,243 @@
+/* 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): Vincent Rouvreau
+ *
+ * Copyright (C) 2015 INRIA Saclay (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/>.
+ */
+
+#define BOOST_TEST_DYN_LINK
+#define BOOST_TEST_MODULE "alpha_complex"
+#include <boost/test/unit_test.hpp>
+
+#include <CGAL/Delaunay_triangulation.h>
+#include <CGAL/Epick_d.h>
+
+#include <cmath> // float comparison
+#include <limits>
+#include <string>
+#include <vector>
+
+#include <gudhi/Alpha_complex.h>
+
+// Use dynamic_dimension_tag for the user to be able to set dimension
+typedef CGAL::Epick_d< CGAL::Dynamic_dimension_tag > Kernel_d;
+// The triangulation uses the default instantiation of the TriangulationDataStructure template parameter
+
+BOOST_AUTO_TEST_CASE(ALPHA_DOC_OFF_file) {
+ // ----------------------------------------------------------------------------
+ //
+ // Init of an alpha-complex from a OFF file
+ //
+ // ----------------------------------------------------------------------------
+ std::string off_file_name("alphacomplexdoc.off");
+ double max_alpha_square_value = 60.0;
+ std::cout << "========== OFF FILE NAME = " << off_file_name << " - alpha²=" <<
+ max_alpha_square_value << "==========" << std::endl;
+
+ Gudhi::alphacomplex::Alpha_complex<Kernel_d> alpha_complex_from_file(off_file_name, max_alpha_square_value);
+
+ const int DIMENSION = 2;
+ std::cout << "alpha_complex_from_file.dimension()=" << alpha_complex_from_file.dimension() << std::endl;
+ BOOST_CHECK(alpha_complex_from_file.dimension() == DIMENSION);
+
+ const int NUMBER_OF_VERTICES = 7;
+ std::cout << "alpha_complex_from_file.num_vertices()=" << alpha_complex_from_file.num_vertices() << std::endl;
+ BOOST_CHECK(alpha_complex_from_file.num_vertices() == NUMBER_OF_VERTICES);
+
+ const int NUMBER_OF_SIMPLICES = 25;
+ std::cout << "alpha_complex_from_file.num_simplices()=" << alpha_complex_from_file.num_simplices() << std::endl;
+ BOOST_CHECK(alpha_complex_from_file.num_simplices() == NUMBER_OF_SIMPLICES);
+
+}
+
+BOOST_AUTO_TEST_CASE(ALPHA_DOC_OFF_file_filtered) {
+ // ----------------------------------------------------------------------------
+ //
+ // Init of an alpha-complex from a OFF file
+ //
+ // ----------------------------------------------------------------------------
+ std::string off_file_name("alphacomplexdoc.off");
+ double max_alpha_square_value = 59.0;
+ std::cout << "========== OFF FILE NAME = " << off_file_name << " - alpha²=" <<
+ max_alpha_square_value << "==========" << std::endl;
+
+ // Use of the default dynamic kernel
+ Gudhi::alphacomplex::Alpha_complex<> alpha_complex_from_file(off_file_name, max_alpha_square_value);
+
+ const int DIMENSION = 2;
+ std::cout << "alpha_complex_from_file.dimension()=" << alpha_complex_from_file.dimension() << std::endl;
+ BOOST_CHECK(alpha_complex_from_file.dimension() == DIMENSION);
+
+ const int NUMBER_OF_VERTICES = 7;
+ std::cout << "alpha_complex_from_file.num_vertices()=" << alpha_complex_from_file.num_vertices() << std::endl;
+ BOOST_CHECK(alpha_complex_from_file.num_vertices() == NUMBER_OF_VERTICES);
+
+ const int NUMBER_OF_SIMPLICES = 23;
+ std::cout << "alpha_complex_from_file.num_simplices()=" << alpha_complex_from_file.num_simplices() << std::endl;
+ BOOST_CHECK(alpha_complex_from_file.num_simplices() == NUMBER_OF_SIMPLICES);
+}
+
+bool are_almost_the_same(float a, float b) {
+ return std::fabs(a - b) < std::numeric_limits<float>::epsilon();
+}
+
+// Use dynamic_dimension_tag for the user to be able to set dimension
+typedef CGAL::Epick_d< CGAL::Dimension_tag<4> > Kernel_s;
+typedef Kernel_s::Point_d Point;
+typedef std::vector<Point> Vector_of_points;
+
+
+bool is_point_in_list(Vector_of_points points_list, Point point) {
+ for (auto& point_in_list : points_list) {
+ if (point_in_list == point) {
+ return true; // point found
+ }
+ }
+ return false; // point not found
+}
+
+BOOST_AUTO_TEST_CASE(Alpha_complex_from_points) {
+ // ----------------------------------------------------------------------------
+ // 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
+ // ----------------------------------------------------------------------------
+ Gudhi::alphacomplex::Alpha_complex<Kernel_s> alpha_complex_from_points(points);
+
+ std::cout << "========== Alpha_complex_from_points ==========" << std::endl;
+
+ // Another way to check num_simplices
+ std::cout << "Iterator on alpha complex simplices in the filtration order, with [filtration value]:" << std::endl;
+ int num_simplices = 0;
+ for (auto f_simplex : alpha_complex_from_points.filtration_simplex_range()) {
+ num_simplices++;
+ 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;
+ }
+ BOOST_CHECK(num_simplices == 15);
+ std::cout << "alpha_complex_from_points.num_simplices()=" << alpha_complex_from_points.num_simplices() << std::endl;
+ BOOST_CHECK(alpha_complex_from_points.num_simplices() == 15);
+
+ std::cout << "alpha_complex_from_points.dimension()=" << alpha_complex_from_points.dimension() << std::endl;
+ BOOST_CHECK(alpha_complex_from_points.dimension() == 4);
+ std::cout << "alpha_complex_from_points.num_vertices()=" << alpha_complex_from_points.num_vertices() << std::endl;
+ BOOST_CHECK(alpha_complex_from_points.num_vertices() == 4);
+
+ for (auto f_simplex : alpha_complex_from_points.filtration_simplex_range()) {
+ switch (alpha_complex_from_points.dimension(f_simplex)) {
+ case 0:
+ BOOST_CHECK(are_almost_the_same(alpha_complex_from_points.filtration(f_simplex), 0.0));
+ break;
+ case 1:
+ BOOST_CHECK(are_almost_the_same(alpha_complex_from_points.filtration(f_simplex), 1.0/2.0));
+ break;
+ case 2:
+ BOOST_CHECK(are_almost_the_same(alpha_complex_from_points.filtration(f_simplex), 2.0/3.0));
+ break;
+ case 3:
+ BOOST_CHECK(are_almost_the_same(alpha_complex_from_points.filtration(f_simplex), 3.0/4.0));
+ break;
+ default:
+ BOOST_CHECK(false); // Shall not happen
+ break;
+ }
+ }
+
+ Point p0 = alpha_complex_from_points.get_point(0);
+ std::cout << "alpha_complex_from_points.get_point(0)=" << p0 << std::endl;
+ BOOST_CHECK(4 == p0.dimension());
+ BOOST_CHECK(is_point_in_list(points, p0));
+
+ Point p1 = alpha_complex_from_points.get_point(1);
+ std::cout << "alpha_complex_from_points.get_point(1)=" << p1 << std::endl;
+ BOOST_CHECK(4 == p1.dimension());
+ BOOST_CHECK(is_point_in_list(points, p1));
+
+ Point p2 = alpha_complex_from_points.get_point(2);
+ std::cout << "alpha_complex_from_points.get_point(2)=" << p2 << std::endl;
+ BOOST_CHECK(4 == p2.dimension());
+ BOOST_CHECK(is_point_in_list(points, p2));
+
+ Point p3 = alpha_complex_from_points.get_point(3);
+ std::cout << "alpha_complex_from_points.get_point(3)=" << p3 << std::endl;
+ BOOST_CHECK(4 == p3.dimension());
+ BOOST_CHECK(is_point_in_list(points, p3));
+
+ // Test to the limit
+ BOOST_CHECK_THROW (alpha_complex_from_points.get_point(4), std::out_of_range);
+ BOOST_CHECK_THROW (alpha_complex_from_points.get_point(-1), std::out_of_range);
+ BOOST_CHECK_THROW (alpha_complex_from_points.get_point(1234), std::out_of_range);
+
+ // Test after prune_above_filtration
+ bool modified = alpha_complex_from_points.prune_above_filtration(0.6);
+ if (modified) {
+ alpha_complex_from_points.initialize_filtration();
+ }
+ BOOST_CHECK(modified);
+
+ // Another way to check num_simplices
+ std::cout << "Iterator on alpha complex simplices in the filtration order, with [filtration value]:" << std::endl;
+ num_simplices = 0;
+ for (auto f_simplex : alpha_complex_from_points.filtration_simplex_range()) {
+ num_simplices++;
+ 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;
+ }
+ BOOST_CHECK(num_simplices == 10);
+ std::cout << "alpha_complex_from_points.num_simplices()=" << alpha_complex_from_points.num_simplices() << std::endl;
+ BOOST_CHECK(alpha_complex_from_points.num_simplices() == 10);
+
+ std::cout << "alpha_complex_from_points.dimension()=" << alpha_complex_from_points.dimension() << std::endl;
+ BOOST_CHECK(alpha_complex_from_points.dimension() == 4);
+ std::cout << "alpha_complex_from_points.num_vertices()=" << alpha_complex_from_points.num_vertices() << std::endl;
+ BOOST_CHECK(alpha_complex_from_points.num_vertices() == 4);
+
+ for (auto f_simplex : alpha_complex_from_points.filtration_simplex_range()) {
+ switch (alpha_complex_from_points.dimension(f_simplex)) {
+ case 0:
+ BOOST_CHECK(are_almost_the_same(alpha_complex_from_points.filtration(f_simplex), 0.0));
+ break;
+ case 1:
+ BOOST_CHECK(are_almost_the_same(alpha_complex_from_points.filtration(f_simplex), 1.0/2.0));
+ break;
+ default:
+ BOOST_CHECK(false); // Shall not happen
+ break;
+ }
+ }
+
+}
diff --git a/src/Alpha_complex/test/CMakeLists.txt b/src/Alpha_complex/test/CMakeLists.txt
new file mode 100644
index 00000000..e24588d7
--- /dev/null
+++ b/src/Alpha_complex/test/CMakeLists.txt
@@ -0,0 +1,45 @@
+cmake_minimum_required(VERSION 2.6)
+project(GUDHIAlphaComplexTest)
+
+if (GCOVR_PATH)
+ # for gcovr to make coverage reports - Corbera Jenkins plugin
+ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fprofile-arcs -ftest-coverage")
+endif()
+if (GPROF_PATH)
+ # for gprof to make coverage reports - Jenkins
+ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -pg")
+endif()
+
+# need CGAL 4.7
+# cmake -DCGAL_DIR=~/workspace/CGAL-4.7-Ic-41 ../../..
+if(CGAL_FOUND)
+ if (NOT CGAL_VERSION VERSION_LESS 4.7.0)
+ message(STATUS "CGAL version: ${CGAL_VERSION}.")
+
+ find_package(Eigen3 3.1.0)
+ if (EIGEN3_FOUND)
+ message(STATUS "Eigen3 version: ${EIGEN3_VERSION}.")
+ include( ${EIGEN3_USE_FILE} )
+ include_directories (BEFORE "../../include")
+
+ add_executable ( AlphaComplexUT Alpha_complex_unit_test.cpp )
+ target_link_libraries(AlphaComplexUT ${Boost_SYSTEM_LIBRARY} ${CGAL_LIBRARY} ${Boost_UNIT_TEST_FRAMEWORK_LIBRARY})
+ if (TBB_FOUND)
+ target_link_libraries(AlphaComplexUT ${TBB_RELEASE_LIBRARY})
+ endif()
+
+ # Do not forget to copy test files in current binary dir
+ file(COPY "${CMAKE_SOURCE_DIR}/data/points/alphacomplexdoc.off" DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/)
+
+ add_test(AlphaComplexUT ${CMAKE_CURRENT_BINARY_DIR}/AlphaComplexUT
+ # XML format for Jenkins xUnit plugin
+ --log_format=XML --log_sink=${CMAKE_SOURCE_DIR}/AlphaComplexUT.xml --log_level=test_suite --report_level=no)
+
+ else()
+ message(WARNING "Eigen3 not found. Version 3.1.0 is required for Alpha complex feature.")
+ endif()
+ else()
+ message(WARNING "CGAL version: ${CGAL_VERSION} is too old to compile Alpha complex feature. Version 4.6.0 is required.")
+ endif ()
+endif()
+
diff --git a/src/Alpha_complex/test/README b/src/Alpha_complex/test/README
new file mode 100644
index 00000000..45b87d91
--- /dev/null
+++ b/src/Alpha_complex/test/README
@@ -0,0 +1,12 @@
+To compile:
+***********
+
+cmake .
+make
+
+To launch with details:
+***********************
+
+./AlphaComplexUnitTest --report_level=detailed --log_level=all
+
+ ==> echo $? returns 0 in case of success (non-zero otherwise)