Backmerge from trunk.

Alpha complex code review.


git-svn-id: svn+ssh://scm.gforge.inria.fr/svnroot/gudhi/branches/alphashapes@894 636b058d-ea47-450e-bf9e-a15bfbe3eedb

Former-commit-id: 702c4d667de4e7191d1050e6d855d2f79117f954

3 files changed, 146 insertions, 19 deletions

diff --git a/src/Persistent_cohomology/example/CMakeLists.txt b/src/Persistent_cohomology/example/CMakeLists.txt
index 74c2e778..8caf7d8b 100644
--- a/src/Persistent_cohomology/example/CMakeLists.txt
+++ b/src/Persistent_cohomology/example/CMakeLists.txt
@@ -5,6 +5,10 @@ project(GUDHIExPersCohom)
 add_definitions( -DBOOST_ALL_NO_LIB )
 add_definitions( -DBOOST_ALL_DYN_LINK )
 
+add_executable(plain_homology plain_homology.cpp)
+target_link_libraries(plain_homology ${Boost_SYSTEM_LIBRARY})
+add_test(plain_homology ${CMAKE_CURRENT_BINARY_DIR}/plain_homology)
+
 add_executable(persistence_from_simple_simplex_tree persistence_from_simple_simplex_tree.cpp)
 target_link_libraries(persistence_from_simple_simplex_tree ${Boost_SYSTEM_LIBRARY})
 add_test(persistence_from_simple_simplex_tree ${CMAKE_CURRENT_BINARY_DIR}/persistence_from_simple_simplex_tree 1 0)
diff --git a/src/Persistent_cohomology/example/performance_rips_persistence.cpp b/src/Persistent_cohomology/example/performance_rips_persistence.cpp
index 0e912d57..fc48d6b1 100644
--- a/src/Persistent_cohomology/example/performance_rips_persistence.cpp
+++ b/src/Persistent_cohomology/example/performance_rips_persistence.cpp
@@ -63,10 +63,11 @@ void timing_persistence(FilteredComplex & cpx
  */
 int main(int argc, char * argv[]) {
   std::chrono::time_point<std::chrono::system_clock> start, end;
-  int enlapsed_sec;
+  int elapsed_sec;
+  {
 
-  std::string filepoints = "../examples/Kl.txt";
-  Filtration_value threshold = 0.3;
+  std::string filepoints = "../../../data/points/Kl.txt";
+  Filtration_value threshold = 0.27;
   int dim_max = 3;
   int p = 2;
   int q = 1223;
@@ -81,8 +82,8 @@ int main(int argc, char * argv[]) {
   Graph_t prox_graph = compute_proximity_graph(points, threshold
                                                , euclidean_distance<Point_t>);
   end = std::chrono::system_clock::now();
-  enlapsed_sec = std::chrono::duration_cast<std::chrono::seconds>(end - start).count();
-  std::cout << "Compute Rips graph in " << enlapsed_sec << " sec.\n";
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "Compute Rips graph in " << elapsed_sec << " ms.\n";
 
   // Construct the Rips complex in a Simplex Tree
   Simplex_tree<> st;
@@ -94,8 +95,8 @@ int main(int argc, char * argv[]) {
   st.expansion(dim_max);
 
   end = std::chrono::system_clock::now();
-  enlapsed_sec = std::chrono::duration_cast<std::chrono::seconds>(end - start).count();
-  std::cout << "Compute Rips complex in " << enlapsed_sec << " sec.\n";
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "Compute Rips complex in " << elapsed_sec << " ms.\n";
   std::cout << "  - dimension           = " << st.dimension() << std::endl;
   std::cout << "  - number of simplices = " << st.num_simplices() << std::endl;
 
@@ -103,15 +104,26 @@ int main(int argc, char * argv[]) {
   start = std::chrono::system_clock::now();
   st.initialize_filtration();
   end = std::chrono::system_clock::now();
-  enlapsed_sec = std::chrono::duration_cast<std::chrono::seconds>(end - start).count();
-  std::cout << "Order the simplices of the filtration in " << enlapsed_sec << " sec.\n";
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "Order the simplices of the filtration in " << elapsed_sec << " ms.\n";
+
+  // Copy the keys inside the simplices
+  start = std::chrono::system_clock::now();
+  {
+    int count = 0;
+    for (auto sh : st.filtration_simplex_range())
+      st.assign_key(sh, count++);
+  }
+  end = std::chrono::system_clock::now();
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "Copied the keys inside the simplices in " << elapsed_sec << " ms.\n";
 
   // Convert the simplex tree into a hasse diagram
   start = std::chrono::system_clock::now();
   Hasse_complex<> hcpx(st);
   end = std::chrono::system_clock::now();
-  enlapsed_sec = std::chrono::duration_cast<std::chrono::seconds>(end - start).count();
-  std::cout << "Convert the simplex tree into a Hasse diagram in " << enlapsed_sec << " sec.\n";
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "Convert the simplex tree into a Hasse diagram in " << elapsed_sec << " ms.\n";
 
 
   std::cout << "Timings when using a simplex tree: \n";
@@ -124,6 +136,11 @@ int main(int argc, char * argv[]) {
   timing_persistence(hcpx, q);
   timing_persistence(hcpx, p, q);
 
+  start = std::chrono::system_clock::now();
+  }
+  end = std::chrono::system_clock::now();
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "Running the complex destructors in " << elapsed_sec << " ms.\n";
   return 0;
 }
 
@@ -132,19 +149,32 @@ void
 timing_persistence(FilteredComplex & cpx
                    , int p) {
   std::chrono::time_point<std::chrono::system_clock> start, end;
-  int enlapsed_sec;
-
+  int elapsed_sec;
+  {
+  start = std::chrono::system_clock::now();
   Persistent_cohomology< FilteredComplex, Field_Zp > pcoh(cpx);
+  end = std::chrono::system_clock::now();
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "  Initialize pcoh in " << elapsed_sec << " ms.\n";
   // initializes the coefficient field for homology
+  start = std::chrono::system_clock::now();
   pcoh.init_coefficients(p);
+  end = std::chrono::system_clock::now();
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "  Initialize the coefficient field in " << elapsed_sec << " ms.\n";
 
   start = std::chrono::system_clock::now();
 
   pcoh.compute_persistent_cohomology(INFINITY);
 
   end = std::chrono::system_clock::now();
-  enlapsed_sec = std::chrono::duration_cast<std::chrono::seconds>(end - start).count();
-  std::cout << "  Compute persistent homology in Z/" << p << "Z in " << enlapsed_sec << " sec.\n";
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "  Compute persistent homology in Z/" << p << "Z in " << elapsed_sec << " ms.\n";
+  start = std::chrono::system_clock::now();
+  }
+  end = std::chrono::system_clock::now();
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "  Run the persistence destructors in " << elapsed_sec << " ms.\n";
 }
 
 template< typename FilteredComplex>
@@ -153,11 +183,19 @@ timing_persistence(FilteredComplex & cpx
                    , int p
                    , int q) {
   std::chrono::time_point<std::chrono::system_clock> start, end;
-  int enlapsed_sec;
-
+  int elapsed_sec;
+  {
+  start = std::chrono::system_clock::now();
   Persistent_cohomology< FilteredComplex, Multi_field > pcoh(cpx);
+  end = std::chrono::system_clock::now();
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "  Initialize pcoh in " << elapsed_sec << " ms.\n";
   // initializes the coefficient field for homology
+  start = std::chrono::system_clock::now();
   pcoh.init_coefficients(p, q);
+  end = std::chrono::system_clock::now();
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "  Initialize the coefficient field in " << elapsed_sec << " ms.\n";
   // compute persistent homology, disgarding persistent features of life shorter than min_persistence
 
   start = std::chrono::system_clock::now();
@@ -165,7 +203,12 @@ timing_persistence(FilteredComplex & cpx
   pcoh.compute_persistent_cohomology(INFINITY);
 
   end = std::chrono::system_clock::now();
-  enlapsed_sec = std::chrono::duration_cast<std::chrono::seconds>(end - start).count();
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
   std::cout << "  Compute multi-field persistent homology in all coefficient fields Z/pZ "
-      << "with p in [" << p << ";" << q << "] in " << enlapsed_sec << " sec.\n";
+      << "with p in [" << p << ";" << q << "] in " << elapsed_sec << " ms.\n";
+  start = std::chrono::system_clock::now();
+  }
+  end = std::chrono::system_clock::now();
+  elapsed_sec = std::chrono::duration_cast<std::chrono::milliseconds>(end - start).count();
+  std::cout << "  Run the persistence destructors in " << elapsed_sec << " ms.\n";
 }
diff --git a/src/Persistent_cohomology/example/plain_homology.cpp b/src/Persistent_cohomology/example/plain_homology.cpp
new file mode 100644
index 00000000..e293e013
--- /dev/null
+++ b/src/Persistent_cohomology/example/plain_homology.cpp
@@ -0,0 +1,80 @@
+/*    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):       Marc Glisse
+ *
+ *    Copyright (C) 2015  INRIA Saclay - Ile-de-France (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/>.
+ */
+
+#include <gudhi/Simplex_tree.h>
+#include <gudhi/Persistent_cohomology.h>
+
+#include <iostream>
+
+using namespace Gudhi;
+
+struct MyOptions : Simplex_tree_options_full_featured {
+  // Implicitly use 0 as filtration value for all simplices
+  static const bool store_filtration = false;
+  // The persistence algorithm needs this
+  static const bool store_key = true;
+  // I have few vertices
+  typedef short Vertex_handle;
+};
+typedef Simplex_tree<MyOptions> ST;
+
+int main() {
+  ST st;
+
+  /* Complex to build. */
+  /*    1   3          */
+  /*    o---o          */
+  /*   /X\ /           */
+  /*  o---o   o        */
+  /*  2   0   4        */
+
+  const short triangle012[] = {0, 1, 2};
+  const short edge03[] = {0, 3};
+  const short edge13[] = {1, 3};
+  const short vertex4[] = {4};
+  st.insert_simplex_and_subfaces(triangle012);
+  st.insert_simplex_and_subfaces(edge03);
+  st.insert_simplex(edge13);
+  st.insert_simplex(vertex4);
+  // FIXME: Remove this line
+  st.set_dimension(2);
+
+  // Sort the simplices in the order of the filtration
+  st.initialize_filtration();
+
+  // Class for homology computation
+  persistent_cohomology::Persistent_cohomology<ST, persistent_cohomology::Field_Zp> pcoh(st);
+
+  // Initialize the coefficient field Z/2Z for homology
+  pcoh.init_coefficients(2);
+
+  // Compute the persistence diagram of the complex
+  pcoh.compute_persistent_cohomology();
+
+  // Print the result. The format is, on each line: 2 dim 0 inf
+  // where 2 represents the field, dim the dimension of the feature.
+  // 2  0 0 inf 
+  // 2  0 0 inf 
+  // 2  1 0 inf 
+  // means that in Z/2Z-homology, the Betti numbers are b0=2 and b1=1.
+  pcoh.output_diagram();
+}