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-rw-r--r--src/Nerve_GIC/doc/COPYRIGHT19
-rw-r--r--src/Nerve_GIC/doc/GIC.jpgbin0 -> 457905 bytes
-rw-r--r--src/Nerve_GIC/doc/GIC.pdfbin0 -> 26073 bytes
-rw-r--r--src/Nerve_GIC/doc/Intro_graph_induced_complex.h214
-rw-r--r--src/Nerve_GIC/doc/coordGICvisu.pdfbin0 -> 20745 bytes
-rw-r--r--src/Nerve_GIC/doc/coordGICvisu2.jpgbin0 -> 1259868 bytes
-rw-r--r--src/Nerve_GIC/doc/funcGICvisu.jpgbin0 -> 71647 bytes
-rw-r--r--src/Nerve_GIC/doc/gicvisu.jpgbin0 -> 167192 bytes
-rw-r--r--src/Nerve_GIC/doc/gicvoronoivisu.jpgbin0 -> 37785 bytes
-rw-r--r--src/Nerve_GIC/doc/nerve.pngbin0 -> 45129 bytes
-rw-r--r--src/Nerve_GIC/doc/nervevisu.jpgbin0 -> 127619 bytes
-rw-r--r--src/Nerve_GIC/example/CMakeLists.txt29
-rw-r--r--src/Nerve_GIC/example/CoordGIC.cpp88
-rw-r--r--src/Nerve_GIC/example/FuncGIC.cpp88
-rw-r--r--src/Nerve_GIC/example/GIC.cpp90
-rwxr-xr-xsrc/Nerve_GIC/example/KeplerMapperVisuFromTxtFile.py70
-rw-r--r--src/Nerve_GIC/example/Nerve.cpp90
-rw-r--r--src/Nerve_GIC/example/Nerve.txt43
-rw-r--r--src/Nerve_GIC/example/VoronoiGIC.cpp86
-rwxr-xr-xsrc/Nerve_GIC/example/km.py390
-rw-r--r--src/Nerve_GIC/example/km.py.COPYRIGHT26
-rw-r--r--src/Nerve_GIC/include/gudhi/GIC.h975
-rw-r--r--src/Nerve_GIC/test/CMakeLists.txt14
-rw-r--r--src/Nerve_GIC/test/data/cloud6
-rw-r--r--src/Nerve_GIC/test/data/cover3
-rw-r--r--src/Nerve_GIC/test/data/graph3
-rw-r--r--src/Nerve_GIC/test/test_GIC.cpp78
27 files changed, 2312 insertions, 0 deletions
diff --git a/src/Nerve_GIC/doc/COPYRIGHT b/src/Nerve_GIC/doc/COPYRIGHT
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+The files of this directory are part of the Gudhi Library. The Gudhi library
+(Geometric Understanding in Higher Dimensions) is a generic C++ library for
+computational topology.
+
+Author(s): Mathieu Carrière
+
+Copyright (C) 2017 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/>.
diff --git a/src/Nerve_GIC/doc/GIC.jpg b/src/Nerve_GIC/doc/GIC.jpg
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diff --git a/src/Nerve_GIC/doc/GIC.pdf b/src/Nerve_GIC/doc/GIC.pdf
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diff --git a/src/Nerve_GIC/doc/Intro_graph_induced_complex.h b/src/Nerve_GIC/doc/Intro_graph_induced_complex.h
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@@ -0,0 +1,214 @@
+/* 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): Mathieu Carriere
+ *
+ * Copyright (C) 2017 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 DOC_COVER_COMPLEX_INTRO_COVER_COMPLEX_H_
+#define DOC_COVER_COMPLEX_INTRO_COVER_COMPLEX_H_
+
+namespace Gudhi {
+
+namespace cover_complex {
+
+/** \defgroup cover_complex Cover complex
+ *
+ * \author Mathieu Carrière
+ *
+ * @{
+ *
+ * Visualizations of the simplicial complexes can be done with either
+ * neato (from <a target="_blank" href="http://www.graphviz.org/">graphviz</a>),
+ * <a target="_blank" href="http://www.geomview.org/">geomview</a>,
+ * <a target="_blank" href="https://github.com/MLWave/kepler-mapper">KeplerMapper</a>.
+ * Input point clouds are assumed to be <a target="_blank" href="http://www.geomview.org/docs/html/OFF.html">OFF files</a>.
+ *
+ * \section covers Covers
+ *
+ * Nerves and Graph Induced Complexes require a cover C of the input point cloud P,
+ * that is a set of subsets of P whose union is P itself.
+ * Very often, this cover is obtained from the preimage of a family of intervals covering
+ * the image of some scalar-valued function f defined on P. This family is parameterized
+ * by its resolution, which can be either the number or the length of the intervals,
+ * and its gain, which is the overlap percentage between consecutive intervals (ordered by their first values).
+ *
+ * \section nerves Nerves
+ *
+ * \subsection nervedefinition Nerve definition
+ *
+ * Assume you are given a cover C of your point cloud P. Then, the Nerve of this cover
+ * is the simplicial complex that has one k-simplex per k-fold intersection of cover elements.
+ * See also <a target="_blank" href="https://en.wikipedia.org/wiki/Nerve_of_a_covering"> Wikipedia </a>.
+ *
+ * \image html "nerve.png" "Nerve of a double torus"
+ *
+ * \subsection nerveexample Example
+ *
+ * This example builds the Nerve of a point cloud sampled on a 3D human shape (human.off).
+ * The cover C comes from the preimages of intervals (10 intervals with gain 0.3)
+ * covering the height function (coordinate 2),
+ * which are then refined into their connected components using the triangulation of the .OFF file.
+ *
+ * \include Nerve_GIC/Nerve.cpp
+ *
+ * When launching:
+ *
+ * \code $> ./Nerve ../../../../data/points/human.off 2 10 0.3 --v
+ * \endcode
+ *
+ * the program output is:
+ *
+ * \include Nerve_GIC/Nerve.txt
+ *
+ * The program also writes a file SC.txt. The first three lines in this file are the location of the input point cloud and the function used to compute the cover.
+ * The fourth line contains the number of vertices nv and edges ne of the Nerve.
+ * The next nv lines represent the vertices. Each line contains the vertex ID,
+ * the number of data points it contains, and their average color function value.
+ * Finally, the next ne lines represent the edges, characterized by the ID of their vertices.
+ *
+ * Using KeplerMapper, one can obtain the following visualization:
+ *
+ * \image html "nervevisu.jpg" "Visualization with KeplerMapper"
+ *
+ * \section gic Graph Induced Complexes (GIC)
+ *
+ * \subsection gicdefinition GIC definition
+ *
+ * Again, assume you are given a cover C of your point cloud P. Moreover, assume
+ * you are also given a graph G built on top of P. Then, for any clique in G
+ * whose nodes all belong to different elements of C, the GIC includes a corresponding
+ * simplex, whose dimension is the number of nodes in the clique minus one.
+ * See \cite Dey13 for more details.
+ *
+ * \image html "GIC.jpg" "GIC of a point cloud."
+ *
+ * \subsection gicexamplevor Example with cover from Voronoï
+ *
+ * This example builds the GIC of a point cloud sampled on a 3D human shape (human.off).
+ * We randomly subsampled 100 points in the point cloud, which act as seeds of
+ * a geodesic Voronoï diagram. Each cell of the diagram is then an element of C.
+ * The graph G (used to compute both the geodesics for Voronoï and the GIC)
+ * comes from the triangulation of the human shape. Note that the resulting simplicial complex is in dimension 3
+ * in this example.
+ *
+ * \include Nerve_GIC/VoronoiGIC.cpp
+ *
+ * When launching:
+ *
+ * \code $> ./VoronoiGIC ../../../../data/points/human.off 700 --v
+ * \endcode
+ *
+ * the program outputs SC.off. Using e.g.
+ *
+ * \code $> geomview SC.off
+ * \endcode
+ *
+ * one can obtain the following visualization:
+ *
+ * \image html "gicvoronoivisu.jpg" "Visualization with Geomview"
+ *
+ * \subsection functionalGICdefinition Functional GIC
+ *
+ * If one restricts to the cliques in G whose nodes all belong to preimages of consecutive
+ * intervals (assuming the cover of the height function is minimal, i.e. no more than
+ * two intervals can intersect at a time), the GIC is of dimension one, i.e. a graph.
+ * We call this graph the functional GIC. See \cite Carriere16 for more details.
+ *
+ * \subsection functionalGICexample Example
+ *
+ * Functional GIC comes with automatic selection of the Rips threshold,
+ * the resolution and the gain of the function cover. See \cite Carriere17c for more details. In this example,
+ * we compute the functional GIC of a Klein bottle embedded in R^5,
+ * where the graph G comes from a Rips complex with automatic threshold,
+ * and the cover C comes from the preimages of intervals covering the first coordinate,
+ * with automatic resolution and gain. Note that automatic threshold, resolution and gain
+ * can be computed as well for the Nerve.
+ *
+ * \include Nerve_GIC/CoordGIC.cpp
+ *
+ * When launching:
+ *
+ * \code $> ./CoordGIC ../../../../data/points/KleinBottle5D.off 0 --v
+ * \endcode
+ *
+ * the program outputs SC.dot. Using e.g.
+ *
+ * \code $> neato SC.dot -Tpdf -o SC.pdf
+ * \endcode
+ *
+ * one can obtain the following visualization:
+ *
+ * \image html "coordGICvisu2.jpg" "Visualization with Neato"
+ *
+ * where nodes are colored by the filter function values and, for each node, the first number is its ID
+ * and the second is the number of data points that its contain.
+ *
+ * We also provide an example on a set of 72 pictures taken around the same object (lucky_cat.off).
+ * The function is now the first eigenfunction given by PCA, whose values
+ * are written in a file (lucky_cat_PCA1). Threshold, resolution and gain are automatically selected as before.
+ *
+ * \include Nerve_GIC/FuncGIC.cpp
+ *
+ * When launching:
+ *
+ * \code $> ./FuncGIC ../../../../data/points/COIL_database/lucky_cat.off ../../../../data/points/COIL_database/lucky_cat_PCA1 --v
+ * \endcode
+ *
+ * the program outputs again SC.dot which gives the following visualization after using neato:
+ *
+ * \image html "funcGICvisu.jpg" "Visualization with neato"
+ *
+ * \copyright GNU General Public License v3.
+ * \verbatim Contact: gudhi-users@lists.gforge.inria.fr \endverbatim
+ */
+/** @} */ // end defgroup cover_complex
+
+} // namespace cover_complex
+
+} // namespace Gudhi
+
+#endif // DOC_COVER_COMPLEX_INTRO_COVER_COMPLEX_H_
+
+
+/* * \subsection gicexample Example with cover from function
+ *
+ * This example builds the GIC of a point cloud sampled on a 3D human shape (human.off).
+ * The cover C comes from the preimages of intervals (with length 0.075 and gain 0)
+ * covering the height function (coordinate 2),
+ * and the graph G comes from a Rips complex built with threshold 0.075.
+ * Note that if the gain is too big, the number of cliques increases a lot,
+ * which make the computation time much larger.
+ *
+ * \include Nerve_GIC/GIC.cpp
+ *
+ * When launching:
+ *
+ * \code $> ./GIC ../../../../data/points/human.off 0.075 2 0.075 0 --v
+ * \endcode
+ *
+ * the program outputs SC.txt, which can be visualized with python and firefox as before:
+ *
+ * \image html "gicvisu.jpg" "Visualization with KeplerMapper"
+ * */
+
+
+/* * Using e.g.
+ *
+ * \code $> python KeplerMapperVisuFromTxtFile.py && firefox SC.html
+ * \endcode */
diff --git a/src/Nerve_GIC/doc/coordGICvisu.pdf b/src/Nerve_GIC/doc/coordGICvisu.pdf
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diff --git a/src/Nerve_GIC/doc/gicvoronoivisu.jpg b/src/Nerve_GIC/doc/gicvoronoivisu.jpg
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diff --git a/src/Nerve_GIC/doc/nerve.png b/src/Nerve_GIC/doc/nerve.png
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diff --git a/src/Nerve_GIC/example/CMakeLists.txt b/src/Nerve_GIC/example/CMakeLists.txt
new file mode 100644
index 00000000..461b6db2
--- /dev/null
+++ b/src/Nerve_GIC/example/CMakeLists.txt
@@ -0,0 +1,29 @@
+cmake_minimum_required(VERSION 2.6)
+project(Nerve_GIC_examples)
+
+add_executable ( Nerve Nerve.cpp )
+add_executable ( CoordGIC CoordGIC.cpp )
+add_executable ( FuncGIC FuncGIC.cpp )
+add_executable ( VoronoiGIC VoronoiGIC.cpp )
+
+if (TBB_FOUND)
+ target_link_libraries(Nerve ${TBB_LIBRARIES})
+ target_link_libraries(CoordGIC ${TBB_LIBRARIES})
+ target_link_libraries(FuncGIC ${TBB_LIBRARIES})
+ target_link_libraries(VoronoiGIC ${TBB_LIBRARIES})
+endif()
+
+file(COPY KeplerMapperVisuFromTxtFile.py km.py DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/)
+
+add_test(NAME Nerve_GIC_example_nerve COMMAND $<TARGET_FILE:Nerve>
+ "${CMAKE_SOURCE_DIR}/data/points/human.off" "2" "10" "0.3")
+
+add_test(NAME Nerve_GIC_example_VoronoiGIC COMMAND $<TARGET_FILE:VoronoiGIC>
+ "${CMAKE_SOURCE_DIR}/data/points/human.off" "100")
+
+add_test(NAME Nerve_GIC_example_CoordGIC COMMAND $<TARGET_FILE:CoordGIC>
+ "${CMAKE_SOURCE_DIR}/data/points/tore3D_1307.off" "0")
+
+add_test(NAME Nerve_GIC_example_FuncGIC COMMAND $<TARGET_FILE:FuncGIC>
+ "${CMAKE_SOURCE_DIR}/data/points/COIL_database/lucky_cat.off"
+ "${CMAKE_SOURCE_DIR}/data/points/COIL_database/lucky_cat_PCA1")
diff --git a/src/Nerve_GIC/example/CoordGIC.cpp b/src/Nerve_GIC/example/CoordGIC.cpp
new file mode 100644
index 00000000..f23e3f55
--- /dev/null
+++ b/src/Nerve_GIC/example/CoordGIC.cpp
@@ -0,0 +1,88 @@
+/* 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): Mathieu Carrière
+ *
+ * Copyright (C) 2017 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/>.
+ */
+
+#include <gudhi/GIC.h>
+
+void usage(int nbArgs, char * const progName) {
+ std::cerr << "Error: Number of arguments (" << nbArgs << ") is not correct\n";
+ std::cerr << "Usage: " << progName << " filename.off coordinate [--v] \n";
+ std::cerr << " i.e.: " << progName << " ../../../../data/points/human.off 2 --v \n";
+ exit(-1); // ----- >>
+}
+
+int main(int argc, char **argv) {
+ if ((argc != 3) && (argc != 4)) usage(argc, argv[0]);
+
+ using Point = std::vector<float>;
+
+ std::string off_file_name(argv[1]);
+ int coord = atoi(argv[2]);
+ bool verb = 0; if(argc == 4) verb = 1;
+
+ // -----------------------------------------
+ // Init of a functional GIC from an OFF file
+ // -----------------------------------------
+
+ Gudhi::cover_complex::Cover_complex<Point> GIC;
+ GIC.set_verbose(verb);
+
+ bool check = GIC.read_point_cloud(off_file_name);
+
+ if(!check) std::cout << "Incorrect OFF file." << std::endl;
+ else{
+
+ GIC.set_type("GIC");
+
+ GIC.set_color_from_coordinate(coord);
+ GIC.set_function_from_coordinate(coord);
+
+ GIC.set_graph_from_automatic_rips(Gudhi::Euclidean_distance());
+ GIC.set_automatic_resolution(); GIC.set_gain();
+ GIC.set_cover_from_function();
+
+ GIC.find_simplices();
+
+ GIC.plot_DOT();
+
+ Gudhi::Simplex_tree<> stree; GIC.create_complex(stree);
+
+ // --------------------------------------------
+ // Display information about the functional GIC
+ // --------------------------------------------
+
+ if(verb){
+ std::cout << "Functional GIC is of dimension " << stree.dimension() <<
+ " - " << stree.num_simplices() << " simplices - " <<
+ stree.num_vertices() << " vertices." << std::endl;
+
+ std::cout << "Iterator on functional GIC simplices" << std::endl;
+ for (auto f_simplex : stree.filtration_simplex_range()) {
+ for (auto vertex : stree.simplex_vertex_range(f_simplex)) {
+ std::cout << vertex << " ";
+ }
+ std::cout << std::endl;
+ }
+ }
+ }
+
+ return 0;
+}
diff --git a/src/Nerve_GIC/example/FuncGIC.cpp b/src/Nerve_GIC/example/FuncGIC.cpp
new file mode 100644
index 00000000..1601ddab
--- /dev/null
+++ b/src/Nerve_GIC/example/FuncGIC.cpp
@@ -0,0 +1,88 @@
+/* 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): Mathieu Carrière
+ *
+ * Copyright (C) 2017 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/>.
+ */
+
+#include <gudhi/GIC.h>
+
+void usage(int nbArgs, char * const progName) {
+ std::cerr << "Error: Number of arguments (" << nbArgs << ") is not correct\n";
+ std::cerr << "Usage: " << progName << " filename.off function [--v] \n";
+ std::cerr << " i.e.: " << progName << " ../../../../data/points/COIL_database/lucky_cat.off ../../../../data/points/COIL_database/lucky_cat_PCA1 --v \n";
+ exit(-1); // ----- >>
+}
+
+int main(int argc, char **argv) {
+ if ((argc != 3) && (argc != 4)) usage(argc, argv[0]);
+
+ using Point = std::vector<float>;
+
+ std::string off_file_name(argv[1]);
+ std::string func_file_name = argv[2];
+ bool verb = 0; if(argc == 4) verb = 1;
+
+ // -----------------------------------------
+ // Init of a functional GIC from an OFF file
+ // -----------------------------------------
+
+ Gudhi::cover_complex::Cover_complex<Point> GIC;
+ GIC.set_verbose(verb);
+
+ bool check = GIC.read_point_cloud(off_file_name);
+
+ if(!check) std::cout << "Incorrect OFF file." << std::endl;
+ else{
+
+ GIC.set_type("GIC");
+
+ GIC.set_color_from_file(func_file_name);
+ GIC.set_function_from_file(func_file_name);
+
+ GIC.set_graph_from_automatic_rips(Gudhi::Euclidean_distance());
+ GIC.set_automatic_resolution(); GIC.set_gain();
+ GIC.set_cover_from_function();
+
+ GIC.find_simplices();
+
+ GIC.plot_DOT();
+
+ Gudhi::Simplex_tree<> stree; GIC.create_complex(stree);
+
+ // --------------------------------------------
+ // Display information about the functional GIC
+ // --------------------------------------------
+
+ if(verb){
+ std::cout << "Functional GIC is of dimension " << stree.dimension() <<
+ " - " << stree.num_simplices() << " simplices - " <<
+ stree.num_vertices() << " vertices." << std::endl;
+
+ std::cout << "Iterator on functional GIC simplices" << std::endl;
+ for (auto f_simplex : stree.filtration_simplex_range()) {
+ for (auto vertex : stree.simplex_vertex_range(f_simplex)) {
+ std::cout << vertex << " ";
+ }
+ std::cout << std::endl;
+ }
+ }
+ }
+
+ return 0;
+}
diff --git a/src/Nerve_GIC/example/GIC.cpp b/src/Nerve_GIC/example/GIC.cpp
new file mode 100644
index 00000000..cdfe73a7
--- /dev/null
+++ b/src/Nerve_GIC/example/GIC.cpp
@@ -0,0 +1,90 @@
+/* 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): Mathieu Carrière
+ *
+ * Copyright (C) 2017 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/>.
+ */
+
+#include <gudhi/GIC.h>
+
+void usage(int nbArgs, char * const progName) {
+ std::cerr << "Error: Number of arguments (" << nbArgs << ") is not correct\n";
+ std::cerr << "Usage: " << progName << " filename.off threshold coordinate resolution gain [--v] \n";
+ std::cerr << " i.e.: " << progName << " ../../../../data/points/human.off 0.075 2 0.075 0 --v \n";
+ exit(-1); // ----- >>
+}
+
+int main(int argc, char **argv) {
+ if ((argc != 6) && (argc != 7)) usage(argc, argv[0]);
+
+ using Point = std::vector<float>;
+
+ std::string off_file_name(argv[1]);
+ double threshold = atof(argv[2]);
+ int coord = atoi(argv[3]);
+ double resolution = atof(argv[4]);
+ double gain = atof(argv[5]);
+ bool verb = 0; if(argc == 7) verb = 1;
+
+ // ----------------------------------------------------------------------------
+ // Init of a graph induced complex from an OFF file
+ // ----------------------------------------------------------------------------
+
+ Gudhi::graph_induced_complex::Graph_induced_complex<Point> GIC;
+ GIC.set_verbose(verb);
+
+ bool check = GIC.read_point_cloud(off_file_name);
+
+ if(!check) std::cout << "Incorrect OFF file." << std::endl;
+ else{
+
+ GIC.set_color_from_coordinate(coord);
+ GIC.set_function_from_coordinate(coord);
+
+ GIC.set_graph_from_rips(threshold, Gudhi::Euclidean_distance());
+
+ GIC.set_resolution_with_interval_length(resolution); GIC.set_gain(gain);
+ GIC.set_cover_from_function();
+
+ GIC.find_GIC_simplices();
+
+ GIC.plot_TXT_for_KeplerMapper();
+
+ Gudhi::Simplex_tree<> stree; GIC.create_complex(stree);
+
+ // ----------------------------------------------------------------------------
+ // Display information about the graph induced complex
+ // ----------------------------------------------------------------------------
+
+ if(verb){
+ std::cout << "Graph induced complex is of dimension " << stree.dimension() <<
+ " - " << stree.num_simplices() << " simplices - " <<
+ stree.num_vertices() << " vertices." << std::endl;
+
+ std::cout << "Iterator on graph induced complex simplices" << std::endl;
+ for (auto f_simplex : stree.filtration_simplex_range()) {
+ for (auto vertex : stree.simplex_vertex_range(f_simplex)) {
+ std::cout << vertex << " ";
+ }
+ std::cout << std::endl;
+ }
+ }
+ }
+
+ return 0;
+}
diff --git a/src/Nerve_GIC/example/KeplerMapperVisuFromTxtFile.py b/src/Nerve_GIC/example/KeplerMapperVisuFromTxtFile.py
new file mode 100755
index 00000000..406264ba
--- /dev/null
+++ b/src/Nerve_GIC/example/KeplerMapperVisuFromTxtFile.py
@@ -0,0 +1,70 @@
+import km
+import numpy as np
+from collections import defaultdict
+
+"""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): Mathieu Carriere
+
+ Copyright (C) 2017 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/>.
+"""
+
+__author__ = "Mathieu Carriere"
+__copyright__ = "Copyright (C) 2017 INRIA"
+__license__ = "GPL v3"
+
+network = {}
+mapper = km.KeplerMapper(verbose=0)
+data = np.zeros((3,3))
+projected_data = mapper.fit_transform( data, projection="sum", scaler=None )
+
+f = open('SC.txt','r')
+nodes = defaultdict(list)
+links = defaultdict(list)
+custom = defaultdict(list)
+
+dat = f.readline()
+lens = f.readline()
+color = f.readline();
+param = [float(i) for i in f.readline().split(" ")]
+
+nums = [int(i) for i in f.readline().split(" ")]
+num_nodes = nums[0]
+num_edges = nums[1]
+
+for i in range(0,num_nodes):
+ point = [float(j) for j in f.readline().split(" ")]
+ nodes[ str(int(point[0])) ] = [ int(point[0]), point[1], int(point[2]) ]
+ links[ str(int(point[0])) ] = []
+ custom[ int(point[0]) ] = point[1]
+
+m = min([custom[i] for i in range(0,num_nodes)])
+M = max([custom[i] for i in range(0,num_nodes)])
+
+for i in range(0,num_edges):
+ edge = [int(j) for j in f.readline().split(" ")]
+ links[ str(edge[0]) ].append( str(edge[1]) )
+ links[ str(edge[1]) ].append( str(edge[0]) )
+
+network["nodes"] = nodes
+network["links"] = links
+network["meta"] = lens
+
+mapper.visualize(network, color_function = color, path_html="SC.html", title=dat,
+graph_link_distance=30, graph_gravity=0.1, graph_charge=-120, custom_tooltips=custom, width_html=0,
+height_html=0, show_tooltips=True, show_title=True, show_meta=True, res=param[0],gain=param[1], minimum=m,maximum=M)
diff --git a/src/Nerve_GIC/example/Nerve.cpp b/src/Nerve_GIC/example/Nerve.cpp
new file mode 100644
index 00000000..71f12f5d
--- /dev/null
+++ b/src/Nerve_GIC/example/Nerve.cpp
@@ -0,0 +1,90 @@
+/* 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): Mathieu Carrière
+ *
+ * Copyright (C) 2017 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/>.
+ */
+
+#include <gudhi/GIC.h>
+
+void usage(int nbArgs, char * const progName) {
+ std::cerr << "Error: Number of arguments (" << nbArgs << ") is not correct\n";
+ std::cerr << "Usage: " << progName << " filename.off coordinate resolution gain [--v] \n";
+ std::cerr << " i.e.: " << progName << " ../../data/points/human.off 2 10 0.3 --v \n";
+ exit(-1); // ----- >>
+}
+
+int main(int argc, char **argv) {
+ if ((argc != 5) && (argc != 6)) usage(argc, argv[0]);
+
+ using Point = std::vector<float>;
+
+ std::string off_file_name(argv[1]);
+ int coord = atoi(argv[2]);
+ int resolution = atoi(argv[3]);
+ double gain = atof(argv[4]);
+ bool verb = 0; if(argc == 6) verb = 1;
+
+ // --------------------------------
+ // Init of a Nerve from an OFF file
+ // --------------------------------
+
+ Gudhi::cover_complex::Cover_complex<Point> SC;
+ SC.set_verbose(verb);
+
+ bool check = SC.read_point_cloud(off_file_name);
+
+ if(!check) std::cout << "Incorrect OFF file." << std::endl;
+ else{
+
+ SC.set_type("Nerve");
+
+ SC.set_color_from_coordinate(coord);
+ SC.set_function_from_coordinate(coord);
+
+ SC.set_graph_from_OFF();
+ SC.set_resolution_with_interval_number(resolution); SC.set_gain(gain);
+ SC.set_cover_from_function();
+
+ SC.find_simplices();
+
+ SC.write_info();
+
+ Gudhi::Simplex_tree<> stree; SC.create_complex(stree);
+
+ // ----------------------------------------------------------------------------
+ // Display information about the graph induced complex
+ // ----------------------------------------------------------------------------
+
+ if(verb){
+ std::cout << "Nerve is of dimension " << stree.dimension() <<
+ " - " << stree.num_simplices() << " simplices - " <<
+ stree.num_vertices() << " vertices." << std::endl;
+
+ std::cout << "Iterator on Nerve simplices" << std::endl;
+ for (auto f_simplex : stree.filtration_simplex_range()) {
+ for (auto vertex : stree.simplex_vertex_range(f_simplex)) {
+ std::cout << vertex << " ";
+ }
+ std::cout << std::endl;
+ }
+ }
+ }
+
+ return 0;
+}
diff --git a/src/Nerve_GIC/example/Nerve.txt b/src/Nerve_GIC/example/Nerve.txt
new file mode 100644
index 00000000..2a861c5f
--- /dev/null
+++ b/src/Nerve_GIC/example/Nerve.txt
@@ -0,0 +1,43 @@
+Nerve is of dimension 1 - 41 simplices - 21 vertices.
+Iterator on Nerve simplices
+0
+1
+2
+2 0
+3
+3 1
+4
+4 3
+5
+5 2
+6
+6 4
+7
+7 5
+8
+9
+9 6
+10
+10 7
+11
+12
+12 8
+13
+13 9
+13 10
+14
+14 11
+15
+15 13
+16
+16 12
+17
+17 14
+18
+18 15
+18 16
+18 17
+19
+19 18
+20
+20 19
diff --git a/src/Nerve_GIC/example/VoronoiGIC.cpp b/src/Nerve_GIC/example/VoronoiGIC.cpp
new file mode 100644
index 00000000..8ce64819
--- /dev/null
+++ b/src/Nerve_GIC/example/VoronoiGIC.cpp
@@ -0,0 +1,86 @@
+/* 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): Mathieu Carrière
+ *
+ * Copyright (C) 2017 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/>.
+ */
+
+#include <gudhi/GIC.h>
+
+void usage(int nbArgs, char * const progName) {
+ std::cerr << "Error: Number of arguments (" << nbArgs << ") is not correct\n";
+ std::cerr << "Usage: " << progName << " filename.off N [--v] \n";
+ std::cerr << " i.e.: " << progName << " ../../../../data/points/human.off 100 --v \n";
+ exit(-1); // ----- >>
+}
+
+int main(int argc, char **argv) {
+ if ((argc != 3) && (argc != 4)) usage(argc, argv[0]);
+
+ using Point = std::vector<float>;
+
+ std::string off_file_name(argv[1]);
+ int m = atoi(argv[2]);
+ bool verb = 0; if(argc == 4) verb = 1;
+
+ // ----------------------------------------------------------------------------
+ // Init of a graph induced complex from an OFF file
+ // ----------------------------------------------------------------------------
+
+ Gudhi::cover_complex::Cover_complex<Point> GIC;
+ GIC.set_verbose(verb);
+
+ bool check = GIC.read_point_cloud(off_file_name);
+
+ if(!check) std::cout << "Incorrect OFF file." << std::endl;
+ else{
+
+ GIC.set_type("GIC");
+
+ GIC.set_color_from_coordinate();
+
+ GIC.set_graph_from_OFF();
+ GIC.set_cover_from_Voronoi(Gudhi::Euclidean_distance(),m);
+
+ GIC.find_simplices();
+
+ GIC.plot_OFF();
+
+ Gudhi::Simplex_tree<> stree; GIC.create_complex(stree);
+
+ // ----------------------------------------------------------------------------
+ // Display information about the graph induced complex
+ // ----------------------------------------------------------------------------
+
+ if(verb){
+ std::cout << "Graph induced complex is of dimension " << stree.dimension() <<
+ " - " << stree.num_simplices() << " simplices - " <<
+ stree.num_vertices() << " vertices." << std::endl;
+
+ std::cout << "Iterator on graph induced complex simplices" << std::endl;
+ for (auto f_simplex : stree.filtration_simplex_range()) {
+ for (auto vertex : stree.simplex_vertex_range(f_simplex)) {
+ std::cout << vertex << " ";
+ }
+ std::cout << std::endl;
+ }
+ }
+ }
+
+ return 0;
+}
diff --git a/src/Nerve_GIC/example/km.py b/src/Nerve_GIC/example/km.py
new file mode 100755
index 00000000..53024aab
--- /dev/null
+++ b/src/Nerve_GIC/example/km.py
@@ -0,0 +1,390 @@
+from __future__ import division
+import numpy as np
+from collections import defaultdict
+import json
+import itertools
+from sklearn import cluster, preprocessing, manifold
+from datetime import datetime
+import sys
+
+class KeplerMapper(object):
+ # With this class you can build topological networks from (high-dimensional) data.
+ #
+ # 1) Fit a projection/lens/function to a dataset and transform it.
+ # For instance "mean_of_row(x) for x in X"
+ # 2) Map this projection with overlapping intervals/hypercubes.
+ # Cluster the points inside the interval
+ # (Note: we cluster on the inverse image/original data to lessen projection loss).
+ # If two clusters/nodes have the same members (due to the overlap), then:
+ # connect these with an edge.
+ # 3) Visualize the network using HTML and D3.js.
+ #
+ # functions
+ # ---------
+ # fit_transform: Create a projection (lens) from a dataset
+ # map: Apply Mapper algorithm on this projection and build a simplicial complex
+ # visualize: Turns the complex dictionary into a HTML/D3.js visualization
+
+ def __init__(self, verbose=2):
+ self.verbose = verbose
+
+ self.chunk_dist = []
+ self.overlap_dist = []
+ self.d = []
+ self.nr_cubes = 0
+ self.overlap_perc = 0
+ self.clusterer = False
+
+ def fit_transform(self, X, projection="sum", scaler=preprocessing.MinMaxScaler()):
+ # Creates the projection/lens from X.
+ #
+ # Input: X. Input features as a numpy array.
+ # Output: projected_X. original data transformed to a projection (lens).
+ #
+ # parameters
+ # ----------
+ # projection: Projection parameter is either a string,
+ # a scikit class with fit_transform, like manifold.TSNE(),
+ # or a list of dimension indices.
+ # scaler: if None, do no scaling, else apply scaling to the projection
+ # Default: Min-Max scaling
+
+ self.scaler = scaler
+ self.projection = str(projection)
+
+ # Detect if projection is a class (for scikit-learn)
+ #if str(type(projection))[1:6] == "class": #TODO: de-ugly-fy
+ # reducer = projection
+ # if self.verbose > 0:
+ # try:
+ # projection.set_params(**{"verbose":self.verbose})
+ # except:
+ # pass
+ # print("\n..Projecting data using: \n\t%s\n"%str(projection))
+ # X = reducer.fit_transform(X)
+
+ # Detect if projection is a string (for standard functions)
+ if isinstance(projection, str):
+ if self.verbose > 0:
+ print("\n..Projecting data using: %s"%(projection))
+ # Stats lenses
+ if projection == "sum": # sum of row
+ X = np.sum(X, axis=1).reshape((X.shape[0],1))
+ if projection == "mean": # mean of row
+ X = np.mean(X, axis=1).reshape((X.shape[0],1))
+ if projection == "median": # mean of row
+ X = np.median(X, axis=1).reshape((X.shape[0],1))
+ if projection == "max": # max of row
+ X = np.max(X, axis=1).reshape((X.shape[0],1))
+ if projection == "min": # min of row
+ X = np.min(X, axis=1).reshape((X.shape[0],1))
+ if projection == "std": # std of row
+ X = np.std(X, axis=1).reshape((X.shape[0],1))
+
+ if projection == "dist_mean": # Distance of x to mean of X
+ X_mean = np.mean(X, axis=0)
+ X = np.sum(np.sqrt((X - X_mean)**2), axis=1).reshape((X.shape[0],1))
+
+ # Detect if projection is a list (with dimension indices)
+ if isinstance(projection, list):
+ if self.verbose > 0:
+ print("\n..Projecting data using: %s"%(str(projection)))
+ X = X[:,np.array(projection)]
+
+ # Scaling
+ if scaler is not None:
+ if self.verbose > 0:
+ print("\n..Scaling with: %s\n"%str(scaler))
+ X = scaler.fit_transform(X)
+
+ return X
+
+ def map(self, projected_X, inverse_X=None, clusterer=cluster.DBSCAN(eps=0.5,min_samples=3), nr_cubes=10, overlap_perc=0.1):
+ # This maps the data to a simplicial complex. Returns a dictionary with nodes and links.
+ #
+ # Input: projected_X. A Numpy array with the projection/lens.
+ # Output: complex. A dictionary with "nodes", "links" and "meta information"
+ #
+ # parameters
+ # ----------
+ # projected_X projected_X. A Numpy array with the projection/lens. Required.
+ # inverse_X Numpy array or None. If None then the projection itself is used for clustering.
+ # clusterer Scikit-learn API compatible clustering algorithm. Default: DBSCAN
+ # nr_cubes Int. The number of intervals/hypercubes to create.
+ # overlap_perc Float. The percentage of overlap "between" the intervals/hypercubes.
+
+ start = datetime.now()
+
+ # Helper function
+ def cube_coordinates_all(nr_cubes, nr_dimensions):
+ # Helper function to get origin coordinates for our intervals/hypercubes
+ # Useful for looping no matter the number of cubes or dimensions
+ # Example: if there are 4 cubes per dimension and 3 dimensions
+ # return the bottom left (origin) coordinates of 64 hypercubes,
+ # as a sorted list of Numpy arrays
+ # TODO: elegance-ify...
+ l = []
+ for x in range(nr_cubes):
+ l += [x] * nr_dimensions
+ return [np.array(list(f)) for f in sorted(set(itertools.permutations(l,nr_dimensions)))]
+
+ nodes = defaultdict(list)
+ links = defaultdict(list)
+ complex = {}
+ self.nr_cubes = nr_cubes
+ self.clusterer = clusterer
+ self.overlap_perc = overlap_perc
+
+ if self.verbose > 0:
+ print("Mapping on data shaped %s using dimensions\n"%(str(projected_X.shape)))
+
+ # If inverse image is not provided, we use the projection as the inverse image (suffer projection loss)
+ if inverse_X is None:
+ inverse_X = projected_X
+
+ # We chop up the min-max column ranges into 'nr_cubes' parts
+ self.chunk_dist = (np.max(projected_X, axis=0) - np.min(projected_X, axis=0))/nr_cubes
+
+ # We calculate the overlapping windows distance
+ self.overlap_dist = self.overlap_perc * self.chunk_dist
+
+ # We find our starting point
+ self.d = np.min(projected_X, axis=0)
+
+ # Use a dimension index array on the projected X
+ # (For now this uses the entire dimensionality, but we keep for experimentation)
+ di = np.array([x for x in range(projected_X.shape[1])])
+
+ # Prefix'ing the data with ID's
+ ids = np.array([x for x in range(projected_X.shape[0])])
+ projected_X = np.c_[ids,projected_X]
+ inverse_X = np.c_[ids,inverse_X]
+
+ # Subdivide the projected data X in intervals/hypercubes with overlap
+ if self.verbose > 0:
+ total_cubes = len(cube_coordinates_all(nr_cubes,projected_X.shape[1]))
+ print("Creating %s hypercubes."%total_cubes)
+
+ for i, coor in enumerate(cube_coordinates_all(nr_cubes,di.shape[0])):
+ # Slice the hypercube
+ hypercube = projected_X[ np.invert(np.any((projected_X[:,di+1] >= self.d[di] + (coor * self.chunk_dist[di])) &
+ (projected_X[:,di+1] < self.d[di] + (coor * self.chunk_dist[di]) + self.chunk_dist[di] + self.overlap_dist[di]) == False, axis=1 )) ]
+
+ if self.verbose > 1:
+ print("There are %s points in cube_%s / %s with starting range %s"%
+ (hypercube.shape[0],i,total_cubes,self.d[di] + (coor * self.chunk_dist[di])))
+
+ # If at least one sample inside the hypercube
+ if hypercube.shape[0] > 0:
+ # Cluster the data point(s) in the cube, skipping the id-column
+ # Note that we apply clustering on the inverse image (original data samples) that fall inside the cube.
+ inverse_x = inverse_X[[int(nn) for nn in hypercube[:,0]]]
+
+ clusterer.fit(inverse_x[:,1:])
+
+ if self.verbose > 1:
+ print("Found %s clusters in cube_%s\n"%(np.unique(clusterer.labels_[clusterer.labels_ > -1]).shape[0],i))
+
+ #Now for every (sample id in cube, predicted cluster label)
+ for a in np.c_[hypercube[:,0],clusterer.labels_]:
+ if a[1] != -1: #if not predicted as noise
+ cluster_id = str(coor[0])+"_"+str(i)+"_"+str(a[1])+"_"+str(coor)+"_"+str(self.d[di] + (coor * self.chunk_dist[di])) # TODO: de-rudimentary-ify
+ nodes[cluster_id].append( int(a[0]) ) # Append the member id's as integers
+ else:
+ if self.verbose > 1:
+ print("Cube_%s is empty.\n"%(i))
+
+ # Create links when clusters from different hypercubes have members with the same sample id.
+ candidates = itertools.combinations(nodes.keys(),2)
+ for candidate in candidates:
+ # if there are non-unique members in the union
+ if len(nodes[candidate[0]]+nodes[candidate[1]]) != len(set(nodes[candidate[0]]+nodes[candidate[1]])):
+ links[candidate[0]].append( candidate[1] )
+
+ # Reporting
+ if self.verbose > 0:
+ nr_links = 0
+ for k in links:
+ nr_links += len(links[k])
+ print("\ncreated %s edges and %s nodes in %s."%(nr_links,len(nodes),str(datetime.now()-start)))
+
+ complex["nodes"] = nodes
+ complex["links"] = links
+ complex["meta"] = self.projection
+
+ return complex
+
+ def visualize(self, complex, color_function="", path_html="mapper_visualization_output.html", title="My Data",
+ graph_link_distance=30, graph_gravity=0.1, graph_charge=-120, custom_tooltips=None, width_html=0,
+ height_html=0, show_tooltips=True, show_title=True, show_meta=True, res=0,gain=0,minimum=0,maximum=0):
+ # Turns the dictionary 'complex' in a html file with d3.js
+ #
+ # Input: complex. Dictionary (output from calling .map())
+ # Output: a HTML page saved as a file in 'path_html'.
+ #
+ # parameters
+ # ----------
+ # color_function string. Not fully implemented. Default: "" (distance to origin)
+ # path_html file path as string. Where to save the HTML page.
+ # title string. HTML page document title and first heading.
+ # graph_link_distance int. Edge length.
+ # graph_gravity float. "Gravity" to center of layout.
+ # graph_charge int. charge between nodes.
+ # custom_tooltips None or Numpy Array. You could use "y"-label array for this.
+ # width_html int. Width of canvas. Default: 0 (full width)
+ # height_html int. Height of canvas. Default: 0 (full height)
+ # show_tooltips bool. default:True
+ # show_title bool. default:True
+ # show_meta bool. default:True
+
+ # Format JSON for D3 graph
+ json_s = {}
+ json_s["nodes"] = []
+ json_s["links"] = []
+ k2e = {} # a key to incremental int dict, used for id's when linking
+
+ for e, k in enumerate(complex["nodes"]):
+ # Tooltip and node color formatting, TODO: de-mess-ify
+ if custom_tooltips is not None:
+ tooltip_s = "<h2>Cluster %s</h2>"%k + " ".join(str(custom_tooltips[complex["nodes"][k][0]]).split(" "))
+ if maximum == minimum:
+ tooltip_i = 0
+ else:
+ tooltip_i = int(30*(custom_tooltips[complex["nodes"][k][0]]-minimum)/(maximum-minimum))
+ json_s["nodes"].append({"name": str(k), "tooltip": tooltip_s, "group": 2 * int(np.log(complex["nodes"][k][2])), "color": tooltip_i})
+ else:
+ tooltip_s = "<h2>Cluster %s</h2>Contains %s members."%(k,len(complex["nodes"][k]))
+ json_s["nodes"].append({"name": str(k), "tooltip": tooltip_s, "group": 2 * int(np.log(len(complex["nodes"][k]))), "color": str(k.split("_")[0])})
+ k2e[k] = e
+ for k in complex["links"]:
+ for link in complex["links"][k]:
+ json_s["links"].append({"source": k2e[k], "target":k2e[link],"value":1})
+
+ # Width and height of graph in HTML output
+ if width_html == 0:
+ width_css = "100%"
+ width_js = 'document.getElementById("holder").offsetWidth-20'
+ else:
+ width_css = "%spx" % width_html
+ width_js = "%s" % width_html
+ if height_html == 0:
+ height_css = "100%"
+ height_js = 'document.getElementById("holder").offsetHeight-20'
+ else:
+ height_css = "%spx" % height_html
+ height_js = "%s" % height_html
+
+ # Whether to show certain UI elements or not
+ if show_tooltips == False:
+ tooltips_display = "display: none;"
+ else:
+ tooltips_display = ""
+
+ if show_meta == False:
+ meta_display = "display: none;"
+ else:
+ meta_display = ""
+
+ if show_title == False:
+ title_display = "display: none;"
+ else:
+ title_display = ""
+
+ with open(path_html,"wb") as outfile:
+ html = """<!DOCTYPE html>
+ <meta charset="utf-8">
+ <meta name="generator" content="KeplerMapper">
+ <title>%s | KeplerMapper</title>
+ <link href='https://fonts.googleapis.com/css?family=Roboto:700,300' rel='stylesheet' type='text/css'>
+ <style>
+ * {margin: 0; padding: 0;}
+ html { height: 100%%;}
+ body {background: #111; height: 100%%; font: 100 16px Roboto, Sans-serif;}
+ .link { stroke: #999; stroke-opacity: .333; }
+ .divs div { border-radius: 50%%; background: red; position: absolute; }
+ .divs { position: absolute; top: 0; left: 0; }
+ #holder { position: relative; width: %s; height: %s; background: #111; display: block;}
+ h1 { %s padding: 20px; color: #fafafa; text-shadow: 0px 1px #000,0px -1px #000; position: absolute; font: 300 30px Roboto, Sans-serif;}
+ h2 { text-shadow: 0px 1px #000,0px -1px #000; font: 700 16px Roboto, Sans-serif;}
+ .meta { position: absolute; opacity: 0.9; width: 220px; top: 80px; left: 20px; display: block; %s background: #000; line-height: 25px; color: #fafafa; border: 20px solid #000; font: 100 16px Roboto, Sans-serif;}
+ div.tooltip { position: absolute; width: 380px; display: block; %s padding: 20px; background: #000; border: 0px; border-radius: 3px; pointer-events: none; z-index: 999; color: #FAFAFA;}
+ }
+ </style>
+ <body>
+ <div id="holder">
+ <h1>%s</h1>
+ <p class="meta">
+ <b>Lens</b><br>%s<br><br>
+ <b>Length of intervals</b><br>%s<br><br>
+ <b>Overlap percentage</b><br>%s%%<br><br>
+ <b>Color Function</b><br>%s
+ </p>
+ </div>
+ <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.5.5/d3.min.js"></script>
+ <script>
+ var width = %s,
+ height = %s;
+ var color = d3.scale.ordinal()
+ .domain(["0","1", "2", "3", "4", "5", "6", "7", "8", "9", "10", "11", "12", "13","14","15","16","17","18","19","20","21","22","23","24","25","26","27","28","29","30"])
+ .range(["#FF0000","#FF1400","#FF2800","#FF3c00","#FF5000","#FF6400","#FF7800","#FF8c00","#FFa000","#FFb400","#FFc800","#FFdc00","#FFf000","#fdff00","#b0ff00","#65ff00","#17ff00","#00ff36","#00ff83","#00ffd0","#00e4ff","#00c4ff","#00a4ff","#00a4ff","#0084ff","#0064ff","#0044ff","#0022ff","#0002ff","#0100ff","#0300ff","#0500ff"]);
+ var force = d3.layout.force()
+ .charge(%s)
+ .linkDistance(%s)
+ .gravity(%s)
+ .size([width, height]);
+ var svg = d3.select("#holder").append("svg")
+ .attr("width", width)
+ .attr("height", height);
+
+ var div = d3.select("#holder").append("div")
+ .attr("class", "tooltip")
+ .style("opacity", 0.0);
+
+ var divs = d3.select('#holder').append('div')
+ .attr('class', 'divs')
+ .attr('style', function(d) { return 'overflow: hidden; width: ' + width + 'px; height: ' + height + 'px;'; });
+
+ graph = %s;
+ force
+ .nodes(graph.nodes)
+ .links(graph.links)
+ .start();
+ var link = svg.selectAll(".link")
+ .data(graph.links)
+ .enter().append("line")
+ .attr("class", "link")
+ .style("stroke-width", function(d) { return Math.sqrt(d.value); });
+ var node = divs.selectAll('div')
+ .data(graph.nodes)
+ .enter().append('div')
+ .on("mouseover", function(d) {
+ div.transition()
+ .duration(200)
+ .style("opacity", .9);
+ div .html(d.tooltip + "<br/>")
+ .style("left", (d3.event.pageX + 100) + "px")
+ .style("top", (d3.event.pageY - 28) + "px");
+ })
+ .on("mouseout", function(d) {
+ div.transition()
+ .duration(500)
+ .style("opacity", 0);
+ })
+ .call(force.drag);
+
+ node.append("title")
+ .text(function(d) { return d.name; });
+ force.on("tick", function() {
+ link.attr("x1", function(d) { return d.source.x; })
+ .attr("y1", function(d) { return d.source.y; })
+ .attr("x2", function(d) { return d.target.x; })
+ .attr("y2", function(d) { return d.target.y; });
+ node.attr("cx", function(d) { return d.x; })
+ .attr("cy", function(d) { return d.y; })
+ .attr('style', function(d) { return 'width: ' + (d.group * 2) + 'px; height: ' + (d.group * 2) + 'px; ' + 'left: '+(d.x-(d.group))+'px; ' + 'top: '+(d.y-(d.group))+'px; background: '+color(d.color)+'; box-shadow: 0px 0px 3px #111; box-shadow: 0px 0px 33px '+color(d.color)+', inset 0px 0px 5px rgba(0, 0, 0, 0.2);'})
+ ;
+ });
+ </script>"""%(title,width_css, height_css, title_display, meta_display, tooltips_display, title,complex["meta"],res,gain*100,color_function,width_js,height_js,graph_charge,graph_link_distance,graph_gravity,json.dumps(json_s))
+ outfile.write(html.encode("utf-8"))
+ if self.verbose > 0:
+ print("\nWrote d3.js graph to '%s'"%path_html)
diff --git a/src/Nerve_GIC/example/km.py.COPYRIGHT b/src/Nerve_GIC/example/km.py.COPYRIGHT
new file mode 100644
index 00000000..bef7b121
--- /dev/null
+++ b/src/Nerve_GIC/example/km.py.COPYRIGHT
@@ -0,0 +1,26 @@
+km.py is a fork of https://github.com/MLWave/kepler-mapper.
+Only the visualization part has been kept (Mapper part has been removed).
+
+This file has te following Copyright :
+
+The MIT License (MIT)
+
+Copyright (c) 2015 Triskelion - HJ van Veen - info@mlwave.com
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/src/Nerve_GIC/include/gudhi/GIC.h b/src/Nerve_GIC/include/gudhi/GIC.h
new file mode 100644
index 00000000..ca8727a0
--- /dev/null
+++ b/src/Nerve_GIC/include/gudhi/GIC.h
@@ -0,0 +1,975 @@
+/* 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: Mathieu Carriere
+ *
+ * Copyright (C) 2017 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 GIC_H_
+#define GIC_H_
+
+#include <gudhi/Debug_utils.h>
+#include <gudhi/graph_simplicial_complex.h>
+#include <gudhi/reader_utils.h>
+#include <gudhi/Simplex_tree.h>
+#include <gudhi/Rips_complex.h>
+#include <gudhi/Points_off_io.h>
+#include <gudhi/distance_functions.h>
+
+#include <iostream>
+#include <vector>
+#include <map>
+#include <string>
+#include <limits> // for numeric_limits
+#include <utility> // for pair<>
+#include <algorithm> // for std::max
+#include <random>
+#include <cassert>
+
+namespace Gudhi {
+
+namespace cover_complex {
+
+using Simplex_tree = Gudhi::Simplex_tree<>;
+using Filtration_value = Simplex_tree::Filtration_value;
+using Rips_complex = Gudhi::rips_complex::Rips_complex<Filtration_value>;
+
+
+/**
+ * \class Cover_complex
+ * \brief Cover complex data structure.
+ *
+ * \ingroup cover_complex
+ *
+ * \details
+ * The data structure is a simplicial complex, representing a
+ * Graph Induced simplicial Complex (GIC) or a Nerve,
+ * and whose simplices are computed with a cover C of a point
+ * cloud P, which often comes from the preimages of intervals
+ * covering the image of a function f defined on P.
+ * These intervals are parameterized by their resolution
+ * (either their length or their number)
+ * and their gain (percentage of overlap).
+ * To compute a GIC, one also needs a graph G built on top of P,
+ * whose cliques with vertices belonging to different elements of C
+ * correspond to the simplices of the GIC.
+ *
+ */
+template<typename Point>
+class Cover_complex {
+
+ private:
+ //Graph_induced_complex(std::map<int, double> fun){func = fun;}
+ bool verbose = false; // whether to display information.
+ std::vector<Point> point_cloud;
+ std::vector<std::vector<int> > one_skeleton;
+ typedef int Cover_t; // elements of cover C are indexed by integers.
+ std::vector<std::vector<Cover_t> > simplices;
+ std::map<int, std::vector<Cover_t> > cover;
+ std::map<Cover_t, std::vector<int> > cover_back;
+ int maximal_dim; // maximal dimension of output simplicial complex.
+ int data_dimension; // dimension of input data.
+ int n; // number of points.
+ std::map<Cover_t,int> cover_fct; // integer-valued function that allows to state if two elements of the cover are consecutive or not.
+ std::map<Cover_t,std::pair<int,double> > cover_color; // size and coloring of the vertices of the output simplicial complex.
+ Simplex_tree st;
+
+ std::map<int,std::vector<int> > adjacency_matrix;
+ std::vector<std::vector<double> > distances;
+
+ int resolution_int = -1;
+ double resolution_double = -1;
+ double gain = -1;
+ double rate_constant = 10; // Constant in the subsampling.
+ double rate_power = 0.001; // Power in the subsampling.
+ int mask = 0; // Ignore nodes containing less than mask points.
+
+ std::map<int, double> func;
+ std::map<int, double> func_color;
+ std::vector<int> voronoi_subsamples;
+ std::string cover_name;
+ std::string point_cloud_name;
+ std::string color_name;
+ std::string type; // Nerve or GIC
+ bool functional_cover = false; // whether we use a cover with preimages of a function or not
+
+ // Point comparator
+ struct Less{
+ Less(std::map<int, double> func){Fct = func;}
+ std::map<int, double> Fct;
+ bool operator()(int a, int b){if(Fct[a] == Fct[b]) return a < b; else return Fct[a] < Fct[b];}
+ };
+
+ // DFS
+ private:
+ void dfs(std::map<int,std::vector<int> >& G, int p, std::vector<int>& cc, std::map<int,bool>& visit){
+ cc.push_back(p);
+ visit[p] = true; int neighb = G[p].size();
+ for (int i = 0; i < neighb; i++)
+ if ( visit.find(G[p][i]) != visit.end() )
+ if( !(visit[G[p][i]]) )
+ dfs(G,G[p][i],cc,visit);
+ }
+
+ // Find random number in [0,1].
+ double GetUniform(){
+ static std::default_random_engine re;
+ static std::uniform_real_distribution<double> Dist(0,1);
+ return Dist(re);
+ }
+
+ // Subsample points.
+ void SampleWithoutReplacement(int populationSize, int sampleSize, std::vector<int> & samples){
+ int t = 0; int m = 0; double u;
+ while (m < sampleSize){
+ u = GetUniform();
+ if ( (populationSize - t)*u >= sampleSize - m )
+ t++;
+ else{samples[m] = t; t++; m++;}
+ }
+ }
+
+ private:
+ void fill_adjacency_matrix_from_st(){
+ std::vector<int> empty;
+ for(int i = 0; i < n; i++) adjacency_matrix[i] = empty;
+ for (auto simplex : st.complex_simplex_range()) {
+ if(st.dimension(simplex) == 1){
+ std::vector<int> vertices;
+ for(auto vertex : st.simplex_vertex_range(simplex)) vertices.push_back(vertex);
+ adjacency_matrix[vertices[0]].push_back(vertices[1]); adjacency_matrix[vertices[1]].push_back(vertices[0]);
+ }
+ }
+ }
+
+ public:
+ /** \brief Specifies whether the type of the output simplicial complex.
+ *
+ * @param[in] t string (either "GIC" or "Nerve").
+ *
+ */
+ void set_type(const std::string & t){type = t;}
+
+ public:
+ /** \brief Specifies whether the program should display information or not.
+ *
+ * @param[in] verb boolean (true = display info, false = do not display info).
+ *
+ */
+ void set_verbose(bool verb = false){verbose = verb;}
+
+ public:
+ /** \brief Sets the constants used to subsample the data set. These constants are
+ * explained in \cite Carriere17c.
+ *
+ * @param[in] constant double.
+ * @param[in] power double.
+ *
+ */
+ void set_subsampling(double constant, double power){rate_constant = constant; rate_power = power;}
+
+ public:
+ /** \brief Sets the mask, which is a threshold integer such that nodes in the complex that contain a number of data points which is less than or equal to
+ * this threshold are not displayed.
+ *
+ * @param[in] nodemask integer.
+ *
+ */
+ void set_mask(int nodemask){mask = nodemask;}
+
+ public:
+ /** \brief Reads and stores the input point cloud.
+ *
+ * @param[in] off_file_name name of the input .OFF or .nOFF file.
+ *
+ */
+ bool read_point_cloud(const std::string & off_file_name){
+
+ point_cloud_name = off_file_name; std::ifstream input(off_file_name); std::string line;
+
+ char comment = '#';
+ while(comment == '#'){getline(input, line); if(!line.empty() && !std::all_of(line.begin(),line.end(),isspace)) comment = line[line.find_first_not_of(' ')];}
+ if(std::strcmp((char*) line.c_str(),"nOFF")==0){
+ comment = '#'; while(comment == '#'){getline(input, line); if(!line.empty() && !std::all_of(line.begin(),line.end(),isspace)) comment = line[line.find_first_not_of(' ')];}
+ std::stringstream stream(line); stream >> data_dimension;
+ }
+ else data_dimension = 3;
+
+ comment = '#'; int numedges, numfaces, i, num;
+ while(comment == '#'){getline(input, line); if(!line.empty() && !std::all_of(line.begin(),line.end(),isspace)) comment = line[line.find_first_not_of(' ')];}
+ std::stringstream stream(line); stream >> n; stream >> numfaces; stream >> numedges;
+
+ i = 0; while(i < n){
+ getline(input, line);
+ if(!line.empty() && line[line.find_first_not_of(' ')] != '#' && !std::all_of(line.begin(),line.end(),isspace)){
+ std::vector<double> point; std::istringstream iss(line);
+ point.assign(std::istream_iterator<double>(iss), std::istream_iterator<double>());
+ point_cloud.emplace_back(point.begin(),point.begin()+data_dimension); i++;
+ }
+ }
+
+ i = 0; while(i < numfaces){
+ getline(input, line);
+ if(!line.empty() && line[line.find_first_not_of(' ')] != '#' && !std::all_of(line.begin(),line.end(),isspace)){
+ std::vector<int> simplex; std::istringstream iss(line);
+ simplex.assign(std::istream_iterator<int>(iss), std::istream_iterator<int>());
+ num = simplex[0]; std::vector<int> edge(2);
+ for(int j = 1; j <= num; j++){ for(int k = j+1; k <= num; k++){ edge[0] = simplex[j]; edge[1] = simplex[k]; one_skeleton.push_back(edge); } }
+ i++;
+ }
+ }
+
+ return input.is_open();
+ }
+
+ // *******************************************************************************************************************
+ // Graphs.
+ // *******************************************************************************************************************
+
+ public: // Set graph from file.
+ /** \brief Creates a graph G from a file containing the edges.
+ *
+ * @param[in] graph_file_name name of the input graph file.
+ * The graph file contains one edge per line,
+ * each edge being represented by the IDs of its two nodes.
+ *
+ */
+ void set_graph_from_file(const std::string & graph_file_name){
+ int neighb; std::ifstream input(graph_file_name);
+ std::string line; int edge[2]; int n = 0;
+ while(std::getline(input,line)){
+ std::stringstream stream(line); stream >> edge[0];
+ while(stream >> neighb){edge[1] = neighb; st.insert_simplex_and_subfaces(edge);}
+ n++;
+ }
+
+ fill_adjacency_matrix_from_st();
+
+ }
+
+
+ public: // Set graph from OFF file.
+ /** \brief Creates a graph G from the triangulation given by the input .OFF file.
+ *
+ */
+ void set_graph_from_OFF(){
+
+ int num_edges = one_skeleton.size();
+ if(num_edges > 0){
+ for(int i = 0; i < num_edges; i++) st.insert_simplex_and_subfaces(one_skeleton[i]);
+ fill_adjacency_matrix_from_st();
+ }
+ else std::cout << "No triangulation read in OFF file!" << std::endl;
+
+ }
+
+ public: // Set graph from Rips complex.
+ /** \brief Creates a graph G from a Rips complex.
+ *
+ * @param[in] threshold threshold value for the Rips complex.
+ * @param[in] distance distance used to compute the Rips complex.
+ *
+ */
+ template<typename Distance> void set_graph_from_rips(double threshold, Distance distance){
+
+ Rips_complex rips_complex_from_points(point_cloud, threshold, distance);
+ rips_complex_from_points.create_complex(st, 1);
+ fill_adjacency_matrix_from_st();
+
+ }
+
+
+
+ public: // Pairwise distances.
+ /** \private \brief Computes all pairwise distances.
+ */
+ template<typename Distance> void compute_pairwise_distances(Distance ref_distance){
+
+ double d; std::vector<double> zeros(n); for(int i = 0; i < n; i++) distances.push_back(zeros);
+ std::string distance = point_cloud_name; distance.append("_dist");
+ std::ifstream input(distance.c_str(), std::ios::out | std::ios::binary);
+
+ if(input.good()){
+ if(verbose) std::cout << "Reading distances..." << std::endl;
+ for(int i = 0; i < n; i++){
+ for (int j = i; j < n; j++){
+ input.read((char*) &d,8); distances[i][j] = d; distances[j][i] = d;
+ }
+ }
+ input.close();
+ }
+
+ else{
+ if(verbose) std::cout << "Computing distances..." << std::endl;
+ input.close(); std::ofstream output(distance, std::ios::out | std::ios::binary);
+ for(int i = 0; i < n; i++){
+ int state = (int) floor( 100*(i*1.0+1)/n ) %10;
+ if( state == 0 && verbose) std::cout << "\r" << state << "%" << std::flush;
+ for (int j = i; j < n; j++){
+ double dis = ref_distance(point_cloud[i],point_cloud[j]);
+ distances[i][j] = dis; distances[j][i] = dis;
+ output.write((char*) &dis,8);
+ }
+ }
+ output.close(); if(verbose) std::cout << std::endl;
+ }
+
+ }
+
+ public: // Automatic tuning of Rips complex.
+ /** \brief Creates a graph G from a Rips complex whose threshold value is automatically tuned with subsampling---see \cite Carriere17c.
+ *
+ * @param[in] distance distance between data points.
+ * @param[in] N number of subsampling iteration (the default reasonable value is 100, but there is no guarantee on how to choose it).
+ * @result delta threshold used for computing the Rips complex.
+ *
+ */
+ template<typename Distance> double set_graph_from_automatic_rips(Distance distance, int N = 100){
+
+ int m = floor(n/ std::exp((1+rate_power)*std::log(std::log(n)/std::log(rate_constant))) );
+ m = std::min(m,n-1);
+ std::vector<int> samples(m); double delta = 0;
+
+ if(verbose) std::cout << n << " points in R^" << data_dimension << std::endl;
+ if(verbose) std::cout << "Subsampling " << m << " points" << std::endl;
+
+ if(distances.size() == 0) compute_pairwise_distances(distance);
+
+ //#pragma omp parallel for
+ for (int i = 0; i < N; i++){
+
+ SampleWithoutReplacement(n,m,samples);
+ double hausdorff_dist = 0;
+ for (int j = 0; j < n; j++){
+ double mj = distances[j][samples[0]]; for (int k = 1; k < m; k++) mj = std::min(mj, distances[j][samples[k]]);
+ hausdorff_dist = std::max(hausdorff_dist, mj);
+ }
+ delta += hausdorff_dist/N;
+
+ }
+
+ if(verbose) std::cout << "delta = " << delta << std::endl;
+ Rips_complex rips_complex_from_points(point_cloud, delta, distance);
+ rips_complex_from_points.create_complex(st, 1);
+ fill_adjacency_matrix_from_st();
+
+ return delta;
+
+ }
+
+
+ // *******************************************************************************************************************
+ // Functions.
+ // *******************************************************************************************************************
+
+ public: // Set function from file.
+ /** \brief Creates the function f from a file containing the function values.
+ *
+ * @param[in] func_file_name name of the input function file.
+ *
+ */
+ void set_function_from_file(const std::string & func_file_name){
+ int vertex_id = 0; std::ifstream input(func_file_name); std::string line; double f;
+ while(std::getline(input,line)){
+ std::stringstream stream(line); stream >> f;
+ func.emplace(vertex_id, f); vertex_id++;
+ }
+ functional_cover = true;
+ cover_name = func_file_name;
+ }
+
+ public: // Set function from kth coordinate
+ /** \brief Creates the function f from the k-th coordinate of the point cloud P.
+ *
+ * @param[in] k coordinate to use (start at 0).
+ *
+ */
+ void set_function_from_coordinate(int k){
+ for(int i = 0; i < n; i++) func.emplace(i,point_cloud[i][k]);
+ char coordinate[100]; sprintf(coordinate, "coordinate %d", k);
+ functional_cover = true;
+ cover_name = coordinate;
+ }
+
+ public: // Set function from vector.
+ /** \brief Creates the function f from a vector stored in memory.
+ *
+ * @param[in] function input vector of values.
+ *
+ */
+ template<class InputRange> void set_function_from_range(InputRange const & function){
+ functional_cover = true;
+ int index = 0; for(auto v : function){func.emplace(index, v); index++;}
+ }
+
+ // *******************************************************************************************************************
+ // Covers.
+ // *******************************************************************************************************************
+
+ public: // Automatic tuning of resolution.
+ /** \brief Computes the optimal length of intervals
+ * (i.e. the smallest interval length avoiding discretization artifacts---see \cite Carriere17c) for a functional cover.
+ *
+ * @result reso interval length used to compute the cover.
+ *
+ */
+ double set_automatic_resolution(){
+
+ if(!functional_cover){std::cout << "Cover needs to come from the preimages of a function." << std::endl; return 0;}
+ if(type != "Nerve" && type != "GIC"){std::cout << "Type of complex needs to be specified." << std::endl; return 0;}
+
+ double reso = 0;
+
+ if(type == "GIC"){
+ for (auto simplex : st.complex_simplex_range()) {
+ if(st.dimension(simplex) == 1){
+ std::vector<int> vertices;
+ for(auto vertex : st.simplex_vertex_range(simplex)) vertices.push_back(vertex);
+ reso = std::max(reso, std::abs(func[vertices[0]] - func[vertices[1]]));
+ }
+ }
+ if(verbose) std::cout << "resolution = " << reso << std::endl;
+ resolution_double = reso;
+ }
+
+ if(type == "Nerve"){
+ for (auto simplex : st.complex_simplex_range()) {
+ if(st.dimension(simplex) == 1){
+ std::vector<int> vertices;
+ for(auto vertex : st.simplex_vertex_range(simplex)) vertices.push_back(vertex);
+ reso = std::max(reso, (std::abs(func[vertices[0]] - func[vertices[1]]))/gain);
+ }
+ }
+ if(verbose) std::cout << "resolution = " << reso << std::endl;
+ resolution_double = reso;
+ }
+
+ return reso;
+
+ }
+
+ public:
+ /** \brief Sets a length of intervals from a value stored in memory.
+ *
+ * @param[in] reso length of intervals.
+ *
+ */
+ void set_resolution_with_interval_length(double reso){resolution_double = reso;}
+ /** \brief Sets a number of intervals from a value stored in memory.
+ *
+ * @param[in] reso number of intervals.
+ *
+ */
+ void set_resolution_with_interval_number(int reso){resolution_int = reso;}
+ /** \brief Sets a gain from a value stored in memory (default value 0.3).
+ *
+ * @param[in] g gain.
+ *
+ */
+ void set_gain(double g = 0.3){gain = g;}
+
+
+ public: // Set cover with preimages of function.
+ /** \brief Creates a cover C from the preimages of the function f.
+ *
+ */
+ void set_cover_from_function(){
+
+ if(resolution_double == -1 && resolution_int == -1){ std::cout << "Number and/or length of intervals not specified" << std::endl; return; }
+ if(gain == -1){ std::cout << "Gain not specified" << std::endl; return; }
+
+ // Read function values and compute min and max
+ std::map<int, double>::iterator it;
+ double maxf, minf; minf = std::numeric_limits<float>::max(); maxf = std::numeric_limits<float>::min();
+ for(it = func.begin(); it != func.end(); it++){minf = std::min(minf, it->second); maxf = std::max(maxf, it->second);}
+ int n = func.size(); if(verbose) std::cout << "Min function value = " << minf << " and Max function value = " << maxf << std::endl;
+
+ // Compute cover of im(f)
+ std::vector<std::pair<double,double> > intervals; int res;
+
+ if(resolution_double == -1){ // Case we use an integer for the number of intervals.
+ double incr = (maxf-minf)/resolution_int; double x = minf; double alpha = (incr*gain)/(2-2*gain);
+ double y = minf + incr + alpha; std::pair<double, double> interm(x,y); intervals.push_back(interm);
+ for(int i = 1; i < resolution_int-1; i++){
+ x = minf + i*incr - alpha;
+ y = minf + (i+1)*incr + alpha;
+ std::pair<double, double> inter(x,y); intervals.push_back(inter);
+ }
+ x = minf + (resolution_int-1)*incr - alpha; y = maxf;
+ std::pair<double, double> interM(x,y); intervals.push_back(interM); res = intervals.size();
+ if(verbose)
+ for(int i = 0; i < res; i++) std::cout << "Interval " << i << " = [" << intervals[i].first << ", " << intervals[i].second << "]" << std::endl;
+ }
+
+ else{
+ if(resolution_int == -1){ // Case we use a double for the length of the intervals.
+ double x = minf; double y = x + resolution_double;
+ while(y <= maxf && maxf - (y-gain*resolution_double) >= resolution_double){
+ std::pair<double, double> inter(x,y); intervals.push_back(inter);
+ x = y - gain*resolution_double;
+ y = x + resolution_double;
+ }
+ std::pair<double, double> interM(x,maxf); intervals.push_back(interM); res = intervals.size();
+ if(verbose)
+ for(int i = 0; i < res; i++) std::cout << "Interval " << i << " = [" << intervals[i].first << ", " << intervals[i].second << "]" << std::endl;
+ }
+
+ else{ // Case we use an integer and a double for the length of the intervals.
+ double x = minf; double y = x + resolution_double; int count = 0;
+ while(count < resolution_int && y <= maxf && maxf - (y-gain*resolution_double) >= resolution_double){
+ std::pair<double, double> inter(x,y); intervals.push_back(inter); count++;
+ x = y - gain*resolution_double;
+ y = x + resolution_double;
+ }
+ res = intervals.size();
+ if(verbose)
+ for(int i = 0; i < res; i++) std::cout << "Interval " << i << " = [" << intervals[i].first << ", " << intervals[i].second << "]" << std::endl;
+ }
+ }
+
+ // Sort points according to function values
+ std::vector<int> points(n); for(int i = 0; i < n; i++) points[i] = i;
+ std::sort(points.begin(),points.end(),Less(this->func));
+ int id = 0; int pos = 0;
+
+ for(int i = 0; i < res; i++){
+
+ // Find points in the preimage
+ std::map<int,std::vector<int> > prop;
+ std::pair<double, double> inter1 = intervals[i];
+ int tmp = pos;
+
+ if(i != res-1){
+
+ if(i != 0){
+ std::pair<double, double> inter3 = intervals[i-1];
+ while(func[points[tmp]] < inter3.second && tmp != n){
+ prop[points[tmp]] = adjacency_matrix[points[tmp]];
+ tmp++;
+ }
+ }
+
+ std::pair<double, double> inter2 = intervals[i+1];
+ while(func[points[tmp]] < inter2.first && tmp != n){
+ prop[points[tmp]] = adjacency_matrix[points[tmp]];
+ tmp++;
+ }
+
+ pos = tmp;
+ while(func[points[tmp]] < inter1.second && tmp != n){
+ prop[points[tmp]] = adjacency_matrix[points[tmp]];
+ tmp++;
+ }
+
+ }
+
+ else{
+
+ std::pair<double, double> inter3 = intervals[i-1];
+ while(func[points[tmp]] < inter3.second && tmp != n){
+ prop[points[tmp]] = adjacency_matrix[points[tmp]];
+ tmp++;
+ }
+
+ while(tmp != n){
+ prop[points[tmp]] = adjacency_matrix[points[tmp]];
+ tmp++;
+ }
+
+ }
+
+ // Compute the connected components with DFS
+ std::map<int,bool> visit; if(verbose) std::cout << "Preimage of interval " << i << std::endl;
+ for(std::map<int, std::vector<int> >::iterator it = prop.begin(); it != prop.end(); it++)
+ visit[it->first] = false;
+ if (!(prop.empty())){
+ for(std::map<int, std::vector<int> >::iterator it = prop.begin(); it != prop.end(); it++){
+ if ( !(visit[it->first]) ){
+ std::vector<int> cc; cc.clear();
+ dfs(prop,it->first,cc,visit); int cci = cc.size(); if(verbose) std::cout << "one CC with " << cci << " points, ";
+ double average_col = 0;
+ for(int j = 0; j < cci; j++){cover[cc[j]].push_back(id); cover_back[id].push_back(cc[j]); average_col += func_color[cc[j]]/cci;}
+ cover_fct[id] = i; cover_color[id] = std::pair<int,double>(cci,average_col);
+ id++;
+ }
+ }
+ }
+ if(verbose) std::cout << std::endl;
+ }
+
+ maximal_dim = id-1;
+
+ }
+
+ public: // Set cover from file.
+ /** \brief Creates the cover C from a file containing the cover elements of each point (the order has to be the same
+ * as in the input file!).
+ *
+ * @param[in] cover_file_name name of the input cover file.
+ *
+ */
+ void set_cover_from_file(const std::string & cover_file_name){
+ int vertex_id = 0; Cover_t cov; std::vector<Cover_t> cov_elts, cov_number;
+ std::ifstream input(cover_file_name); std::string line;
+ while(std::getline(input,line)){
+ cov_elts.clear(); std::stringstream stream(line);
+ while(stream >> cov){
+ cov_elts.push_back(cov); cov_number.push_back(cov);
+ cover_fct[cov] = cov; cover_color[cov].second += func_color[vertex_id]; cover_color[cov].first++; cover_back[cov].push_back(vertex_id);
+ }
+ cover[vertex_id] = cov_elts; vertex_id++;
+ }
+ std::vector<Cover_t>::iterator it;
+ std::sort(cov_number.begin(),cov_number.end()); it = std::unique(cov_number.begin(),cov_number.end());
+ cov_number.resize(std::distance(cov_number.begin(),it)); maximal_dim = cov_number.size()-1;
+ for(int i = 0; i <= maximal_dim; i++) cover_color[i].second /= cover_color[i].first;
+ cover_name = cover_file_name;
+ }
+
+ public: // Set cover from Voronoi
+ /** \brief Creates the cover C from the Voronoï cells of a subsampling of the point cloud.
+ *
+ * @param[in] distance distance between the points.
+ * @param[in] m number of points in the subsample.
+ *
+ */
+ template<typename Distance> void set_cover_from_Voronoi(Distance distance, int m = 100){
+
+ voronoi_subsamples.resize(m); SampleWithoutReplacement(n,m,voronoi_subsamples);
+ if(distances.size() == 0) compute_pairwise_distances(distance);
+ std::vector<double> mindist(n); for(int j = 0; j < n; j++) mindist[j] = std::numeric_limits<double>::max();
+
+ // Compute the geodesic distances to subsamples with Dijkstra
+ for(int i = 0; i < m; i++){
+ if(verbose) std::cout << "Computing geodesic distances to seed " << i << "..." << std::endl;
+ int seed = voronoi_subsamples[i];
+ std::vector<double> dist(n); std::vector<int> process(n);
+ for(int j = 0; j < n; j++){ dist[j] = std::numeric_limits<double>::max(); process[j] = j; }
+ dist[seed] = 0; int curr_size = process.size(); int min_point, min_index; double min_dist;
+ std::vector<int> neighbors; int num_neighbors;
+
+ while(curr_size > 0){
+ min_dist = std::numeric_limits<double>::max(); min_index = -1; min_point = -1;
+ for(int j = 0; j < curr_size; j++){
+ if(dist[process[j]] < min_dist){
+ min_point = process[j]; min_dist = dist[process[j]]; min_index = j;
+ }
+ }
+ assert(min_index != -1); process.erase(process.begin() + min_index);
+ assert(min_point != -1); neighbors = adjacency_matrix[min_point]; num_neighbors = neighbors.size();
+ for(int j = 0; j < num_neighbors; j++){
+ double d = dist[min_point] + distances[min_point][neighbors[j]];
+ dist[neighbors[j]] = std::min(dist[neighbors[j]], d);
+ }
+ curr_size = process.size();
+ }
+
+ for(int j = 0; j < n; j++)
+ if(mindist[j] > dist[j]){
+ mindist[j] = dist[j];
+ if(cover[j].size() == 0) cover[j].push_back(i);
+ else cover[j][0] = i;
+ }
+ }
+
+ for(int i = 0; i < n; i++){ cover_back[cover[i][0]].push_back(i); cover_color[cover[i][0]].second += func_color[i]; cover_color[cover[i][0]].first++; }
+ for(int i = 0; i < m; i++) cover_color[i].second /= cover_color[i].first;
+ maximal_dim = m-1; cover_name = "Voronoi";
+
+ }
+
+ public: // return subset of data corresponding to a node
+ /** \brief Returns the data subset corresponding to a specific node of the created complex.
+ *
+ * @param[in] c ID of the node.
+ * @result cover_back(c) vector of IDs of data points.
+ *
+ */
+ const std::vector<int> & subpopulation(Cover_t c){
+ return cover_back[c];
+ }
+
+ // *******************************************************************************************************************
+ // Visualization.
+ // *******************************************************************************************************************
+
+ public: // Set color from file.
+ /** \brief Computes the function used to color the nodes of the simplicial complex from a file containing the function values.
+ *
+ * @param[in] color_file_name name of the input color file.
+ *
+ */
+ void set_color_from_file(const std::string & color_file_name){
+ int vertex_id = 0; std::ifstream input(color_file_name); std::string line; double f;
+ while(std::getline(input,line)){
+ std::stringstream stream(line); stream >> f;
+ func_color.emplace(vertex_id, f); vertex_id++;
+ }
+ color_name = color_file_name;
+ }
+
+ public: // Set color from kth coordinate
+ /** \brief Computes the function used to color the nodes of the simplicial complex from the k-th coordinate.
+ *
+ * @param[in] k coordinate to use (start at 0).
+ *
+ */
+ void set_color_from_coordinate(int k = 0){
+ for(int i = 0; i < n; i++) func_color.emplace(i, point_cloud[i][k]);
+ color_name = "coordinate "; color_name.append(std::to_string(k));
+ }
+
+ public: // Set color from vector.
+ /** \brief Computes the function used to color the nodes of the simplicial complex from a vector stored in memory.
+ *
+ * @param[in] color input vector of values.
+ *
+ */
+ void set_color_from_vector(std::vector<double> color){
+ for(unsigned int i = 0; i < color.size(); i++) func_color.emplace(i, color[i]);
+ }
+
+ public: // Create a .dot file that can be compiled with neato to produce a .pdf file.
+ /** \brief Creates a .dot file called SC.dot for neato (part of the graphviz package) once the simplicial complex is computed to get a visualization
+ * of its 1-skeleton in a .pdf file.
+ */
+ void plot_DOT(){
+ char mapp[11] = "SC.dot"; std::ofstream graphic(mapp); graphic << "graph GIC {" << std::endl;
+ double maxv, minv; maxv = std::numeric_limits<double>::min(); minv = std::numeric_limits<double>::max();
+ for (std::map<Cover_t,std::pair<int,double> >::iterator iit = cover_color.begin(); iit != cover_color.end(); iit++){
+ maxv = std::max(maxv, iit->second.second); minv = std::min(minv, iit->second.second);
+ }
+ int k = 0; std::vector<int> nodes; nodes.clear();
+ for (std::map<Cover_t,std::pair<int,double> >::iterator iit = cover_color.begin(); iit != cover_color.end(); iit++){
+ if(iit->second.first > mask){
+ nodes.push_back(iit->first);
+ graphic << iit->first << "[shape=circle fontcolor=black color=black label=\"" \
+ << iit->first << ":" << iit->second.first << "\" style=filled fillcolor=\"" \
+ << (1-(maxv-iit->second.second)/(maxv-minv))*0.6 << ", 1, 1\"]" << std::endl;
+ k++;
+ }
+ }
+ int ke = 0; int num_simplices = simplices.size();
+ for (int i = 0; i < num_simplices; i++)
+ if (simplices[i].size() == 2)
+ if (cover_color[simplices[i][0]].first > mask && cover_color[simplices[i][1]].first > mask){
+ graphic << " " << simplices[i][0] << " -- " << simplices[i][1] << " [weight=15];" << std::endl; ke++;}
+ graphic << "}"; graphic.close();
+ std::cout << "SC.dot generated. It can be visualized with e.g. neato." << std::endl;
+ }
+
+ public: // Create a .txt file that can be compiled with KeplerMapper.
+ /** \brief Creates a .txt file called SC.txt describing the 1-skeleton, which can then be plotted with e.g. KeplerMapper.
+ */
+ void write_info(){
+
+ int num_simplices = simplices.size(); int num_edges = 0;
+ char mapp[11] = "SC.txt"; std::ofstream graphic(mapp);
+ for (int i = 0; i < num_simplices; i++)
+ if (simplices[i].size() == 2)
+ if (cover_color[simplices[i][0]].first > mask && cover_color[simplices[i][1]].first > mask)
+ num_edges++;
+
+ graphic << point_cloud_name << std::endl;
+ graphic << cover_name << std::endl;
+ graphic << color_name << std::endl;
+ graphic << resolution_double << " " << gain << std::endl;
+ graphic << cover_color.size() << " " << num_edges << std::endl;
+
+ for (std::map<Cover_t,std::pair<int,double> >::iterator iit = cover_color.begin(); iit != cover_color.end(); iit++)
+ graphic << iit->first << " " << iit->second.second << " " << iit->second.first << std::endl;
+
+ for (int i = 0; i < num_simplices; i++)
+ if (simplices[i].size() == 2)
+ if (cover_color[simplices[i][0]].first > mask && cover_color[simplices[i][1]].first > mask)
+ graphic << simplices[i][0] << " " << simplices[i][1] << std::endl;
+ graphic.close();
+ std::cout << "SC.txt generated. It can be visualized with e.g. python KeplerMapperVisuFromTxtFile.py and firefox." << std::endl;
+ }
+
+
+ public: // Create a .off file that can be visualized (e.g. with Geomview).
+ /** \brief Creates a .off file called SC.off for 3D visualization, which contains the 2-skeleton of the GIC.
+ * This function assumes that the cover has been computed with Voronoi. If data points are in 1D or 2D,
+ * the remaining coordinates of the points embedded in 3D are set to 0.
+ */
+ void plot_OFF(){
+
+ assert(cover_name == "Voronoi");
+ char gic[11] = "SC.off"; std::ofstream graphic(gic);
+ graphic << "OFF" << std::endl; int m = voronoi_subsamples.size(); int numedges = 0; int numfaces = 0;
+ std::vector<std::vector<int> > edges, faces; int numsimplices = simplices.size();
+ for (int i = 0; i < numsimplices; i++) {
+ if(simplices[i].size() == 2){ numedges++; edges.push_back(simplices[i]); }
+ if(simplices[i].size() == 3){ numfaces++; faces.push_back(simplices[i]); }
+ }
+ graphic << m << " " << numedges + numfaces << std::endl;
+ for(int i = 0; i < m; i++){
+ if(data_dimension <= 3){
+ for(int j = 0; j < data_dimension; j++) graphic << point_cloud[voronoi_subsamples[i]][j] << " ";
+ for(int j = data_dimension; j < 3; j++) graphic << 0 << " ";
+ graphic << std::endl;
+ }
+ else for(int j = 0; j < 3; j++) graphic << point_cloud[voronoi_subsamples[i]][j] << " ";
+ }
+ for(int i = 0; i < numedges; i++) graphic << 2 << " " << edges[i][0] << " " << edges[i][1] << std::endl;
+ for(int i = 0; i < numfaces; i++) graphic << 3 << " " << faces[i][0] << " " << faces[i][1] << " " << faces[i][2] << std::endl;
+ graphic.close();
+ std::cout << "SC.off generated. It can be visualized with e.g. geomview." << std::endl;
+
+ }
+
+ // *******************************************************************************************************************
+ // *******************************************************************************************************************
+
+
+ public:
+ /** \brief Creates the simplicial complex.
+ *
+ * @param[in] complex SimplicialComplexForRips to be created.
+ *
+ */
+ template<typename SimplicialComplexForRips>
+ void create_complex(SimplicialComplexForRips & complex) {
+ unsigned int dimension = 0;
+ for(auto const& simplex : simplices){
+ complex.insert_simplex_and_subfaces(simplex);
+ if(dimension < simplex.size()-1) dimension = simplex.size()-1;
+ }
+ complex.set_dimension(dimension);
+ }
+
+ public:
+ /** \brief Computes the simplices of the simplicial complex.
+ */
+ void find_simplices(){
+
+ if(type != "Nerve" && type != "GIC"){std::cout << "Type of complex needs to be specified." << std::endl; return;}
+
+ if(type == "Nerve"){
+ for(std::map<int,std::vector<Cover_t> >::iterator it = cover.begin(); it!=cover.end(); it++) simplices.push_back(it->second);
+ std::vector<std::vector<Cover_t> >::iterator it;
+ std::sort(simplices.begin(),simplices.end()); it = std::unique(simplices.begin(),simplices.end());
+ simplices.resize(std::distance(simplices.begin(),it));
+ }
+
+ if(type == "GIC"){
+
+ if(functional_cover){
+
+ // Computes the simplices in the GIC by looking at all the edges of the graph and adding the
+ // corresponding edges in the GIC if the images of the endpoints belong to consecutive intervals.
+
+ if (gain >= 0.5)
+ throw std::invalid_argument("the output of this function is correct ONLY if the cover is minimal, i.e. the gain is less than 0.5.");
+
+ int v1, v2;
+
+ // Loop on all points.
+ for(std::map<int,std::vector<Cover_t> >::iterator it = cover.begin(); it != cover.end(); it++){
+
+ int vid = it->first; std::vector<int> neighbors = adjacency_matrix[vid]; int num_neighb = neighbors.size();
+
+ // Find cover of current point (vid).
+ if(cover[vid].size() == 2) v1 = std::min(cover[vid][0],cover[vid][1]); else v1 = cover[vid][0];
+ std::vector<int> node(1); node[0] = v1; simplices.push_back(node);
+
+ // Loop on neighbors.
+ for(int i = 0; i < num_neighb; i++){
+
+ int neighb = neighbors[i];
+
+ // Find cover of neighbor (neighb).
+ if(cover[neighb].size() == 2) v2 = std::max(cover[neighb][0],cover[neighb][1]); else v2 = cover[neighb][0];
+
+ // If neighbor is in next interval, add edge.
+ if(cover_fct[v2] == cover_fct[v1] + 1){
+ std::vector<int> edge(2); edge[0] = v1; edge[1] = v2;
+ simplices.push_back(edge);
+ }
+ }
+ }
+ std::vector<std::vector<Cover_t> >::iterator it;
+ std::sort(simplices.begin(),simplices.end()); it = std::unique(simplices.begin(),simplices.end());
+ simplices.resize(std::distance(simplices.begin(),it));
+
+ }
+
+ else{
+
+ // Find IDs of edges to remove
+ std::vector<int> simplex_to_remove; int simplex_id = 0;
+ for (auto simplex : st.complex_simplex_range()) {
+ if(st.dimension(simplex) == 1){
+ std::vector<std::vector<Cover_t> > comp;
+ for(auto vertex : st.simplex_vertex_range(simplex)) comp.push_back(cover[vertex]);
+ if(comp[0].size() == 1 && comp[0] == comp[1]) simplex_to_remove.push_back(simplex_id);
+ }
+ simplex_id++;
+ }
+
+ // Remove edges
+ if(simplex_to_remove.size() > 1){
+ int current_id = 1;
+ auto simplex = st.complex_simplex_range().begin(); int num_rem = 0;
+ for(int i = 0; i < simplex_id-1; i++){
+ int j = i+1; auto simplex_tmp = simplex; simplex_tmp++;
+ if(j == simplex_to_remove[current_id]){st.remove_maximal_simplex(*simplex_tmp); current_id++; num_rem++;}
+ else simplex++;
+ } simplex = st.complex_simplex_range().begin();
+ for(int i = 0; i < simplex_to_remove[0]; i++) simplex++; st.remove_maximal_simplex(*simplex);
+ }
+
+ // Build the Simplex Tree corresponding to the graph
+ st.expansion(maximal_dim);
+
+ // Find simplices of GIC
+ simplices.clear();
+ for (auto simplex : st.complex_simplex_range()) {
+ if(!st.has_children(simplex)){
+
+ std::vector<Cover_t> simplx;
+ for (auto vertex : st.simplex_vertex_range(simplex)){
+ unsigned int sz = cover[vertex].size();
+ for(unsigned int i = 0; i < sz; i++){
+ simplx.push_back(cover[vertex][i]);
+ }
+ }
+
+ std::sort(simplx.begin(),simplx.end()); std::vector<Cover_t>::iterator it = std::unique(simplx.begin(),simplx.end());
+ simplx.resize(std::distance(simplx.begin(),it));
+ simplices.push_back(simplx);
+
+ }
+ }
+ std::vector<std::vector<Cover_t> >::iterator it;
+ std::sort(simplices.begin(),simplices.end()); it = std::unique(simplices.begin(),simplices.end());
+ simplices.resize(std::distance(simplices.begin(),it));
+
+ }
+ }
+
+ }
+
+};
+
+} // namespace cover_complex
+
+} // namespace Gudhi
+
+#endif // GIC_H_
diff --git a/src/Nerve_GIC/test/CMakeLists.txt b/src/Nerve_GIC/test/CMakeLists.txt
new file mode 100644
index 00000000..77efe043
--- /dev/null
+++ b/src/Nerve_GIC/test/CMakeLists.txt
@@ -0,0 +1,14 @@
+cmake_minimum_required(VERSION 2.6)
+project(Graph_induced_complex_tests)
+
+include(GUDHI_test_coverage)
+
+add_executable ( Graph_induced_complex_test_unit test_GIC.cpp )
+target_link_libraries(Graph_induced_complex_test_unit ${Boost_UNIT_TEST_FRAMEWORK_LIBRARY})
+if (TBB_FOUND)
+ target_link_libraries(Graph_induced_complex_test_unit ${TBB_LIBRARIES})
+endif()
+
+file(COPY data DESTINATION ${CMAKE_CURRENT_BINARY_DIR}/)
+
+gudhi_add_coverage_test(Graph_induced_complex_test_unit)
diff --git a/src/Nerve_GIC/test/data/cloud b/src/Nerve_GIC/test/data/cloud
new file mode 100644
index 00000000..4a0c170d
--- /dev/null
+++ b/src/Nerve_GIC/test/data/cloud
@@ -0,0 +1,6 @@
+nOFF
+3
+3 0 0
+0 0 0
+2 1 0
+4 0 0 \ No newline at end of file
diff --git a/src/Nerve_GIC/test/data/cover b/src/Nerve_GIC/test/data/cover
new file mode 100644
index 00000000..5f5fbe75
--- /dev/null
+++ b/src/Nerve_GIC/test/data/cover
@@ -0,0 +1,3 @@
+1
+2
+3 \ No newline at end of file
diff --git a/src/Nerve_GIC/test/data/graph b/src/Nerve_GIC/test/data/graph
new file mode 100644
index 00000000..37142800
--- /dev/null
+++ b/src/Nerve_GIC/test/data/graph
@@ -0,0 +1,3 @@
+0 1
+0 2
+1 2 \ No newline at end of file
diff --git a/src/Nerve_GIC/test/test_GIC.cpp b/src/Nerve_GIC/test/test_GIC.cpp
new file mode 100644
index 00000000..d7af7680
--- /dev/null
+++ b/src/Nerve_GIC/test/test_GIC.cpp
@@ -0,0 +1,78 @@
+/* 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): Mathieu Carrière
+ *
+ * Copyright (C) 2017 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/>.
+ */
+
+#define BOOST_TEST_DYN_LINK
+#define BOOST_TEST_MODULE "graph_induced_complex"
+
+#include <boost/test/unit_test.hpp>
+#include <cmath> // float comparison
+#include <limits>
+#include <string>
+#include <vector>
+#include <algorithm> // std::max
+#include <gudhi/GIC.h>
+#include <gudhi/distance_functions.h>
+#include <gudhi/reader_utils.h>
+
+BOOST_AUTO_TEST_CASE(check_nerve) {
+
+ using Point = std::vector<float>;
+ Gudhi::cover_complex::Cover_complex<Point> N; N.set_type("Nerve");
+ std::string cloud_file_name("data/cloud"); N.read_point_cloud(cloud_file_name);
+ std::string graph_file_name("data/graph"); N.set_graph_from_file(graph_file_name);
+ std::string cover_file_name("data/cover"); N.set_cover_from_file(cover_file_name);
+ N.find_simplices(); Gudhi::Simplex_tree<> stree; N.create_complex(stree);
+
+ BOOST_CHECK(stree.num_vertices() == 3);
+ BOOST_CHECK((stree.num_simplices()-stree.num_vertices()) == 0);
+ BOOST_CHECK(stree.dimension() == 0);
+}
+
+BOOST_AUTO_TEST_CASE(check_GIC) {
+
+ using Point = std::vector<float>;
+ Gudhi::cover_complex::Cover_complex<Point> GIC; GIC.set_type("GIC");
+ std::string cloud_file_name("data/cloud"); GIC.read_point_cloud(cloud_file_name);
+ std::string graph_file_name("data/graph"); GIC.set_graph_from_file(graph_file_name);
+ std::string cover_file_name("data/cover"); GIC.set_cover_from_file(cover_file_name);
+ GIC.find_simplices(); Gudhi::Simplex_tree<> stree; GIC.create_complex(stree);
+
+ BOOST_CHECK(stree.num_vertices() == 3);
+ BOOST_CHECK((stree.num_simplices()-stree.num_vertices()) == 4);
+ BOOST_CHECK(stree.dimension() == 2);
+}
+
+
+BOOST_AUTO_TEST_CASE(check_voronoiGIC) {
+
+ using Point = std::vector<float>;
+ Gudhi::cover_complex::Cover_complex<Point> GIC; GIC.set_type("GIC");
+ std::string cloud_file_name("data/cloud"); GIC.read_point_cloud(cloud_file_name);
+ std::string graph_file_name("data/graph"); GIC.set_graph_from_file(graph_file_name);
+ GIC.set_cover_from_Voronoi(Gudhi::Euclidean_distance(),2);
+ GIC.find_simplices(); Gudhi::Simplex_tree<> stree; GIC.create_complex(stree);
+
+ BOOST_CHECK(stree.num_vertices() == 2);
+ BOOST_CHECK((stree.num_simplices()-stree.num_vertices()) == 1);
+ BOOST_CHECK(stree.dimension() == 1);
+}
+