Add an example showing how to use different options for Simplex_tree.

It has a few FIXMEs for things that are already in progress elsewhere and should be fixed before the release.


git-svn-id: svn+ssh://scm.gforge.inria.fr/svnroot/gudhi/branches/ST-options@750 636b058d-ea47-450e-bf9e-a15bfbe3eedb

Former-commit-id: dda65a6af3112dc14843d764881c22a04ff4b90e

2 files changed, 77 insertions, 3 deletions

diff --git a/src/Simplex_tree/example/CMakeLists.txt b/src/Simplex_tree/example/CMakeLists.txt
index 1a3cdfbf..2f924490 100644
--- a/src/Simplex_tree/example/CMakeLists.txt
+++ b/src/Simplex_tree/example/CMakeLists.txt
@@ -7,15 +7,18 @@ add_test(simplex_tree_from_file_3 ${CMAKE_CURRENT_BINARY_DIR}/simplex_tree_from_
 
 add_executable ( simple_simplex_tree simple_simplex_tree.cpp )
 add_test(simple_simplex_tree ${CMAKE_CURRENT_BINARY_DIR}/simple_simplex_tree)
-   
+
+add_executable ( mini_simplex_tree mini_simplex_tree.cpp )
+add_test(mini_simplex_tree ${CMAKE_CURRENT_BINARY_DIR}/mini_simplex_tree)
+
 
 # An example with Simplex-tree using CGAL alpha_shapes_3
 if(GMP_FOUND AND CGAL_FOUND)
    message("CGAL_lib = ${CGAL_LIBRARIES_DIR}")
-   message("GMP_LIBRARIES = ${GMP_LIBRARIES}")   
+   message("GMP_LIBRARIES = ${GMP_LIBRARIES}")
    INCLUDE_DIRECTORIES(${GMP_INCLUDE_DIR})
    INCLUDE_DIRECTORIES(${CGAL_INCLUDE_DIRS})
    add_executable ( simplex_tree_from_alpha_shapes_3 simplex_tree_from_alpha_shapes_3.cpp )
    target_link_libraries(simplex_tree_from_alpha_shapes_3 ${GMP_LIBRARIES} ${CGAL_LIBRARY})
    add_test(simplex_tree_from_alpha_shapes_3 ${CMAKE_CURRENT_BINARY_DIR}/simplex_tree_from_alpha_shapes_3 ${CMAKE_SOURCE_DIR}/data/points/bunny_5000)
-endif()  
+endif()
diff --git a/src/Simplex_tree/example/mini_simplex_tree.cpp b/src/Simplex_tree/example/mini_simplex_tree.cpp
new file mode 100644
index 00000000..a7e4c27d
--- /dev/null
+++ b/src/Simplex_tree/example/mini_simplex_tree.cpp
@@ -0,0 +1,71 @@
+/*    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/>.
+ */
+
+// FIXME: remove the first include
+#include <gudhi/graph_simplicial_complex.h>
+#include <gudhi/Simplex_tree.h>
+#include <iostream>
+#include <initializer_list>
+
+using namespace Gudhi;
+
+struct MyOptions : Simplex_tree_options_full_featured {
+  // Not doing persistence, so we don't need those
+  static constexpr bool store_key = false;
+  static constexpr bool store_filtration = false;
+  // I have few vertices
+  typedef short Vertex_handle;
+};
+typedef Simplex_tree<MyOptions> ST;
+
+// Dictionary should be private, but for now this is the easiest way.
+static_assert(sizeof(ST::Dictionary::value_type) < sizeof(Simplex_tree<>::Dictionary::value_type),
+    "Not storing the filtration and key should save some space");
+
+int main() {
+  ST st;
+
+  /* Complex to build. */
+  /*    1              */
+  /*    o              */
+  /*   /X\             */
+  /*  o---o---o        */
+  /*  2   0   3        */
+
+  // FIXME: Replace std::vector<short> with auto
+  std::vector<short> triangle012 = {0, 1, 2};
+  std::vector<short> edge03 = {0, 3};
+  st.insert_simplex_and_subfaces(triangle012);
+  st.insert_simplex_and_subfaces(edge03);
+  // FIXME: Remove this line
+  st.set_dimension(2);
+
+  std::vector<short> edge02 = {0, 2};
+  ST::Simplex_handle e = st.find(edge02);
+  assert(st.filtration(e) == 0); // We are not using filtrations so everything has value 0
+  for(ST::Simplex_handle t : st.cofaces_simplex_range(e, 1)) // Only coface is 012
+    {
+      for(ST::Vertex_handle v : st.simplex_vertex_range(t)) // v in { 0, 1, 2 }
+        std::cout << v;
+      std::cout << '\n';
+    }
+}