skbl some cleaning

git-svn-id: svn+ssh://scm.gforge.inria.fr/svnroot/gudhi/trunk@420 636b058d-ea47-450e-bf9e-a15bfbe3eedb

Former-commit-id: 8dab1684f8a9b0987de5ed19863b8173cc71f2f4

2 files changed, 649 insertions, 618 deletions

diff --git a/src/Skeleton_blocker/include/gudhi/Skeleton_blocker_geometric_complex.h b/src/Skeleton_blocker/include/gudhi/Skeleton_blocker_geometric_complex.h
index e2918901..095ebbdc 100644
--- a/src/Skeleton_blocker/include/gudhi/Skeleton_blocker_geometric_complex.h
+++ b/src/Skeleton_blocker/include/gudhi/Skeleton_blocker_geometric_complex.h
@@ -37,86 +37,99 @@ namespace skbl {
  */
 template<typename SkeletonBlockerGeometricDS>
 class Skeleton_blocker_geometric_complex :
-    public Skeleton_blocker_simplifiable_complex<SkeletonBlockerGeometricDS> {
- public:
-  typedef typename SkeletonBlockerGeometricDS::GT GT;
-
-  typedef Skeleton_blocker_simplifiable_complex<SkeletonBlockerGeometricDS> SimplifiableSkeletonblocker;
-
-  typedef typename SimplifiableSkeletonblocker::Vertex_handle Vertex_handle;
-  typedef typename SimplifiableSkeletonblocker::Root_vertex_handle Root_vertex_handle;
-  typedef typename SimplifiableSkeletonblocker::Edge_handle Edge_handle;
-  typedef typename SimplifiableSkeletonblocker::Simplex_handle Simplex_handle;
-
-  typedef typename SimplifiableSkeletonblocker::Graph_vertex Graph_vertex;
-
-  typedef typename SkeletonBlockerGeometricDS::Point Point;
-
-  /**
-   * @brief Add a vertex to the complex with its associated point.
-   */
-  Vertex_handle add_vertex(const Point& point) {
-    Vertex_handle ad = SimplifiableSkeletonblocker::add_vertex();
-    (*this)[ad].point() = point;
-    return ad;
-  }
-
-  /**
-   * @brief Returns the Point associated to the vertex v.
-   */
-  const Point& point(Vertex_handle v) const {
-    assert(this->contains_vertex(v));
-    return (*this)[v].point();
-  }
-
-  /**
-   * @brief Returns the Point associated to the vertex v.
-   */
-  Point& point(Vertex_handle v) {
-    assert(this->contains_vertex(v));
-    return (*this)[v].point();
-  }
-
-  const Point& point(Root_vertex_handle global_v) const {
-    Vertex_handle local_v((*this)[global_v]);
-    assert(this->contains_vertex(local_v));
-    return (*this)[local_v].point();
-  }
-
-  Point& point(Root_vertex_handle global_v) {
-    Vertex_handle local_v((*this)[global_v]);
-    assert(this->contains_vertex(local_v));
-    return (*this)[local_v].point();
-  }
-
-  typedef Skeleton_blocker_link_complex<Skeleton_blocker_geometric_complex> Geometric_link;
-
-  /**
-   * Constructs the link of 'simplex' with points coordinates.
-   */
-  Geometric_link link(const Simplex_handle& simplex) const {
-    Geometric_link link(*this, simplex);
-    // we now add the point info
-    add_points_to_link(link);
-    return link;
-  }
-
-  /**
-   * Constructs the link of 'simplex' with points coordinates.
-   */
-  Geometric_link link(Edge_handle edge) const {
-    Geometric_link link(*this, edge);
-    // we now add the point info
-    add_points_to_link(link);
-    return link;
-  }
- private:
-  void add_points_to_link(Geometric_link& link) const {
-    for (Vertex_handle v : link.vertex_range()) {
-      Root_vertex_handle v_root(link.get_id(v));
-      link.point(v) = (*this).point(v_root);
-    }
-  }
+		public Skeleton_blocker_simplifiable_complex<SkeletonBlockerGeometricDS> {
+		public:
+	typedef typename SkeletonBlockerGeometricDS::GT GT;
+
+	typedef Skeleton_blocker_simplifiable_complex<SkeletonBlockerGeometricDS> SimplifiableSkeletonblocker;
+
+	typedef typename SimplifiableSkeletonblocker::Vertex_handle Vertex_handle;
+	typedef typename SimplifiableSkeletonblocker::Root_vertex_handle Root_vertex_handle;
+	typedef typename SimplifiableSkeletonblocker::Edge_handle Edge_handle;
+	typedef typename SimplifiableSkeletonblocker::Simplex_handle Simplex_handle;
+
+	typedef typename SimplifiableSkeletonblocker::Graph_vertex Graph_vertex;
+
+	typedef typename SkeletonBlockerGeometricDS::Point Point;
+
+	/**
+	 * @brief Add a vertex to the complex with its associated point.
+	 */
+	Vertex_handle add_vertex(const Point& point) {
+		Vertex_handle ad = SimplifiableSkeletonblocker::add_vertex();
+		(*this)[ad].point() = point;
+		return ad;
+	}
+
+	/**
+	 * @brief Returns the Point associated to the vertex v.
+	 */
+	const Point& point(Vertex_handle v) const {
+		assert(this->contains_vertex(v));
+		return (*this)[v].point();
+	}
+
+	/**
+	 * @brief Returns the Point associated to the vertex v.
+	 */
+	Point& point(Vertex_handle v) {
+		assert(this->contains_vertex(v));
+		return (*this)[v].point();
+	}
+
+	const Point& point(Root_vertex_handle global_v) const {
+		Vertex_handle local_v((*this)[global_v]);
+		assert(this->contains_vertex(local_v));
+		return (*this)[local_v].point();
+	}
+
+	Point& point(Root_vertex_handle global_v) {
+		Vertex_handle local_v((*this)[global_v]);
+		assert(this->contains_vertex(local_v));
+		return (*this)[local_v].point();
+	}
+
+	typedef Skeleton_blocker_link_complex<Skeleton_blocker_geometric_complex> Geometric_link;
+
+
+	/**
+	 * Constructs the link of 'simplex' with points coordinates.
+	 */
+	Geometric_link link(Vertex_handle v) const {
+		Geometric_link link(*this, Simplex_handle(v));
+		// we now add the point info
+		add_points_to_link(link);
+		return link;
+	}
+
+
+	/**
+	 * Constructs the link of 'simplex' with points coordinates.
+	 */
+	Geometric_link link(const Simplex_handle& simplex) const {
+		Geometric_link link(*this, simplex);
+		// we now add the point info
+		add_points_to_link(link);
+		return link;
+	}
+
+	/**
+	 * Constructs the link of 'simplex' with points coordinates.
+	 */
+	Geometric_link link(Edge_handle edge) const {
+		Geometric_link link(*this, edge);
+		// we now add the point info
+		add_points_to_link(link);
+		return link;
+	}
+
+		private:
+	void add_points_to_link(Geometric_link& link) const {
+		for (Vertex_handle v : link.vertex_range()) {
+			Root_vertex_handle v_root(link.get_id(v));
+			link.point(v) = (*this).point(v_root);
+		}
+	}
 };
 
 }  // namespace skbl
diff --git a/src/Skeleton_blocker/include/gudhi/Skeleton_blocker_simplifiable_complex.h b/src/Skeleton_blocker/include/gudhi/Skeleton_blocker_simplifiable_complex.h
index 305b8829..6685859c 100644
--- a/src/Skeleton_blocker/include/gudhi/Skeleton_blocker_simplifiable_complex.h
+++ b/src/Skeleton_blocker/include/gudhi/Skeleton_blocker_simplifiable_complex.h
@@ -1,34 +1,30 @@
-/*    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):       David Salinas
- *
- *    Copyright (C) 2014  INRIA Sophia Antipolis-Mediterranee (France)
- *
- *    This program is free software: you can redistribute it and/or modify
- *    it under the terms of the GNU General Public License as published by
- *    the Free Software Foundation, either version 3 of the License, or
- *    (at your option) any later version.
- *
- *    This program is distributed in the hope that it will be useful,
- *    but WITHOUT ANY WARRANTY; without even the implied warranty of
- *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *    GNU General Public License for more details.
- *
- *    You should have received a copy of the GNU General Public License
- *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-#ifndef SRC_SKELETON_BLOCKER_INCLUDE_GUDHI_SKELETON_BLOCKER_SIMPLIFIABLE_COMPLEX_H_
-#define SRC_SKELETON_BLOCKER_INCLUDE_GUDHI_SKELETON_BLOCKER_SIMPLIFIABLE_COMPLEX_H_
+ /*    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):       David Salinas
+  *
+  *    Copyright (C) 2014  INRIA Sophia Antipolis-Mediterranee (France)
+  *
+  *    This program is free software: you can redistribute it and/or modify
+  *    it under the terms of the GNU General Public License as published by
+  *    the Free Software Foundation, either version 3 of the License, or
+  *    (at your option) any later version.
+  *
+  *    This program is distributed in the hope that it will be useful,
+  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  *    GNU General Public License for more details.
+  *
+  *    You should have received a copy of the GNU General Public License
+  *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+  */
+#ifndef GUDHI_SKELETON_BLOCKERS_SIMPLIFIABLE_COMPLEX_H_
+#define GUDHI_SKELETON_BLOCKERS_SIMPLIFIABLE_COMPLEX_H_
 
 #include "gudhi/Skeleton_blocker/Skeleton_blocker_sub_complex.h"
 
-#include <list>
-#include <vector>
-#include <set>
-
-namespace Gudhi {
+namespace Gudhi{
 
 namespace skbl {
 
@@ -39,517 +35,539 @@ namespace skbl {
  * @extends Skeleton_blocker_complex
  */
 template<typename SkeletonBlockerDS>
-class Skeleton_blocker_simplifiable_complex : public Skeleton_blocker_complex<SkeletonBlockerDS> {
-  template<class ComplexType> friend class Skeleton_blocker_sub_complex;
-
- public:
-  typedef Skeleton_blocker_complex<SkeletonBlockerDS> SkeletonBlockerComplex;
-
-  typedef typename SkeletonBlockerComplex::Graph_edge Graph_edge;
-
-  typedef typename SkeletonBlockerComplex::boost_adjacency_iterator boost_adjacency_iterator;
-  typedef typename SkeletonBlockerComplex::Edge_handle Edge_handle;
-  typedef typename SkeletonBlockerComplex::boost_vertex_handle boost_vertex_handle;
-  typedef typename SkeletonBlockerComplex::Vertex_handle Vertex_handle;
-  typedef typename SkeletonBlockerComplex::Root_vertex_handle Root_vertex_handle;
-  typedef typename SkeletonBlockerComplex::Simplex_handle Simplex_handle;
-  typedef typename SkeletonBlockerComplex::Root_simplex_handle Root_simplex_handle;
-  typedef typename SkeletonBlockerComplex::Blocker_handle Blocker_handle;
-
-  typedef typename SkeletonBlockerComplex::Root_simplex_iterator Root_simplex_iterator;
-  typedef typename SkeletonBlockerComplex::Simplex_handle_iterator Simplex_handle_iterator;
-  typedef typename SkeletonBlockerComplex::BlockerMap BlockerMap;
-  typedef typename SkeletonBlockerComplex::BlockerPair BlockerPair;
-  typedef typename SkeletonBlockerComplex::BlockerMapIterator BlockerMapIterator;
-  typedef typename SkeletonBlockerComplex::BlockerMapConstIterator BlockerMapConstIterator;
-
-  typedef typename SkeletonBlockerComplex::Visitor Visitor;
-
-  /** @name Constructors / Destructors / Initialization
-   */
-  //@{
-  Skeleton_blocker_simplifiable_complex(int num_vertices_ = 0,
-                                        Visitor* visitor_ = NULL)
-      : Skeleton_blocker_complex<SkeletonBlockerDS>(num_vertices_, visitor_) {
-  }
-
-  /**
-   * @brief Constructor with a list of simplices
-   * @details The list of simplices must be the list
-   * of simplices of a simplicial complex, sorted with increasing dimension.
-   * todo take iterator instead
-   */
-  Skeleton_blocker_simplifiable_complex(std::list<Simplex_handle>& simplices,
-                                        Visitor* visitor_ = NULL)
-      : Skeleton_blocker_complex<SkeletonBlockerDS>(simplices, visitor_) {
-  }
-
-  virtual ~Skeleton_blocker_simplifiable_complex() {
-  }
-
-  //@}
-
-  /**
-   * Returns true iff the blocker 'sigma' is popable.
-   * To define popable, let us call 'L' the complex that
-   * consists in the current complex without the blocker 'sigma'.
-   * A blocker 'sigma' is then "popable" if the link of 'sigma'
-   * in L is reducible.
-   *
-   */
-  virtual bool is_popable_blocker(Blocker_handle sigma) const {
-    assert(this->contains_blocker(*sigma));
-    Skeleton_blocker_link_complex<Skeleton_blocker_simplifiable_complex> link_blocker_sigma;
-    build_link_of_blocker(*this, *sigma, link_blocker_sigma);
-
-    bool res = link_blocker_sigma.is_contractible() == CONTRACTIBLE;
-    return res;
-  }
-
- private:
-  /**
-   * @returns the list of blockers of the simplex
-   *
-   * @todo a enlever et faire un iterateur sur tous les blockers a la place
-   */
-  std::list<Blocker_handle> get_blockers() {
-    std::list < Blocker_handle > res;
-    for (auto blocker : this->blocker_range()) {
-      res.push_back(blocker);
-    }
-    return res;
-  }
-
- public:
-  /**
-   * Removes all the popable blockers of the complex and delete them.
-   * @returns the number of popable blockers deleted
-   */
-  void remove_popable_blockers() {
-    std::list < Vertex_handle > vertex_to_check;
-    for (auto v : this->vertex_range())
-      vertex_to_check.push_front(v);
-
-    while (!vertex_to_check.empty()) {
-      Vertex_handle v = vertex_to_check.front();
-      vertex_to_check.pop_front();
-
-      bool blocker_popable_found = true;
-      while (blocker_popable_found) {
-        blocker_popable_found = false;
-        for (auto block : this->blocker_range(v)) {
-          if (this->is_popable_blocker(block)) {
-            for (Vertex_handle nv : *block)
-              if (nv != v)
-                vertex_to_check.push_back(nv);
-            this->delete_blocker(block);
-            blocker_popable_found = true;
-            break;
-          }
-        }
-      }
-    }
-  }
-
-  /**
-   * Removes all the popable blockers of the complex passing through v and delete them.
-   */
-  void remove_popable_blockers(Vertex_handle v) {
-    bool blocker_popable_found = true;
-    while (blocker_popable_found) {
-      blocker_popable_found = false;
-      for (auto block : this->blocker_range(v)) {
-        if (is_popable_blocker(block)) {
-          this->delete_blocker(block);
-          blocker_popable_found = true;
-        }
-      }
-    }
-  }
-
-  /**
-   * Remove the star of the vertex 'v'
-   */
-  void remove_star(Vertex_handle v) {
-    // we remove the blockers that are not consistent anymore
-
-    update_blockers_after_remove_star_of_vertex_or_edge(static_cast<Simplex_handle>(v));
-
-    while (this->degree(v) > 0) {
-      Vertex_handle w(*(adjacent_vertices(v.vertex, this->skeleton).first));
-      this->remove_edge(v, w);
-    }
-    this->remove_vertex(v);
-  }
-
- private:
-  /**
-   * after removing the star of a simplex, blockers sigma that contains this simplex must be removed.
-   * Furthermore, all simplices tau of the form sigma \setminus simplex_to_be_removed must be added
-   * whenever the dimension of tau is at least 2.
-   */
-  void update_blockers_after_remove_star_of_vertex_or_edge(
-      const Simplex_handle& simplex_to_be_removed) {
-    std::list < Blocker_handle > blockers_to_update;
-    if (simplex_to_be_removed.empty())
-      return;
-
-    auto v0 = simplex_to_be_removed.first_vertex();
-    for (auto blocker : this->blocker_range(v0)) {
-      if (blocker->contains(simplex_to_be_removed))
-        blockers_to_update.push_back(blocker);
-    }
-
-    for (auto blocker_to_update : blockers_to_update) {
-      Simplex_handle sub_blocker_to_be_added;
-      bool sub_blocker_need_to_be_added = (blocker_to_update->dimension()
-          - simplex_to_be_removed.dimension()) >= 2;
-      if (sub_blocker_need_to_be_added) {
-        sub_blocker_to_be_added = *blocker_to_update;
-        sub_blocker_to_be_added.difference(simplex_to_be_removed);
-      }
-      this->delete_blocker(blocker_to_update);
-      if (sub_blocker_need_to_be_added)
-        this->add_blocker(sub_blocker_to_be_added);
-    }
-  }
-
- public:
-  /**
-   * Remove the star of the edge connecting vertices a and b.
-   * @returns the number of blocker that have been removed
-   */
-  void remove_star(Vertex_handle a, Vertex_handle b) {
-    update_blockers_after_remove_star_of_vertex_or_edge(Simplex_handle(a, b));
-    // we remove the edge
-    this->remove_edge(a, b);
-  }
-
-  /**
-   * Remove the star of the edge 'e'.
-   */
-  void remove_star(Edge_handle e) {
-    return remove_star(this->first_vertex(e), this->second_vertex(e));
-  }
-
-  /**
-   * Remove the star of the simplex 'sigma' which needs to belong to the complex
-   */
-  void remove_star(const Simplex_handle& sigma) {
-    assert(this->contains(sigma));
-    if (sigma.dimension() == 0) {
-      remove_star(sigma.first_vertex());
-    } else if (sigma.dimension() == 1) {
-      remove_star(sigma.first_vertex(), sigma.last_vertex());
-    } else {
-      remove_blocker_containing_simplex(sigma);
-      this->add_blocker(sigma);
-    }
-  }
-
-  /**
-   * @brief add a maximal simplex plus all its cofaces.
-   * @details the simplex must have dimension greater than one (otherwise use add_vertex or add_edge).
-   */
-  void add_simplex(const Simplex_handle& sigma) {
-    assert(!this->contains(sigma));
-    assert(sigma.dimension() > 1);
-    remove_blocker_include_in_simplex(sigma);
-  }
-
- private:
-  /**
-   * remove all blockers that contains sigma
-   */
-  void remove_blocker_containing_simplex(const Simplex_handle& sigma) {
-    std::vector < Blocker_handle > blockers_to_remove;
-    for (auto blocker : this->blocker_range(sigma.first_vertex())) {
-      if (blocker->contains(sigma))
-        blockers_to_remove.push_back(blocker);
-    }
-    for (auto blocker_to_update : blockers_to_remove)
-      this->delete_blocker(blocker_to_update);
-  }
-
-  /**
-   * remove all blockers that contains sigma
-   */
-  void remove_blocker_include_in_simplex(const Simplex_handle& sigma) {
-    std::vector < Blocker_handle > blockers_to_remove;
-    for (auto blocker : this->blocker_range(sigma.first_vertex())) {
-      if (sigma.contains(*blocker))
-        blockers_to_remove.push_back(blocker);
-    }
-    for (auto blocker_to_update : blockers_to_remove)
-      this->delete_blocker(blocker_to_update);
-  }
-
- public:
-  enum simplifiable_status {
-    NOT_HOMOTOPY_EQ,
-    MAYBE_HOMOTOPY_EQ,
-    HOMOTOPY_EQ
-  };
-  simplifiable_status is_remove_star_homotopy_preserving(
-      const Simplex_handle& simplex) {
-    return MAYBE_HOMOTOPY_EQ;
-  }
-
-  enum contractible_status {
-    NOT_CONTRACTIBLE,
-    MAYBE_CONTRACTIBLE,
-    CONTRACTIBLE
-  };
-  /**
-   * @brief %Test if the complex is reducible using a strategy defined in the class
-   * (by default it tests if the complex is a cone)
-   * @details Note that NO could be returned if some invariant ensures that the complex
-   * is not a point (for instance if the euler characteristic is different from 1).
-   * This function will surely have to return MAYBE in some case because the
-   * associated problem is undecidable but it in practice, it can often
-   * be solved with the help of geometry.
-   */
-  virtual contractible_status is_contractible() const {
-    if (this->is_cone())
-      return CONTRACTIBLE;
-    else
-      return MAYBE_CONTRACTIBLE;
-    // return this->is_cone();
-  }
-
-  /** @Edge contraction operations
-   */
-  //@{
-
-  /**
-   * @return If ignore_popable_blockers is true
-   * then the result is true iff the link condition at edge ab is satisfied
-   * or equivalently iff no blocker contains ab.
-   * If ignore_popable_blockers is false then the
-   * result is true iff all blocker containing ab are popable.
-   */
-  bool link_condition(Vertex_handle a, Vertex_handle b,
-                      bool ignore_popable_blockers = false) const {
-    for (auto blocker : this->const_blocker_range(a))
-      if (blocker->contains(b)) {
-        // false if ignore_popable_blockers is false
-        // otherwise the blocker has to be popable
-        return ignore_popable_blockers && is_popable_blocker(blocker);
-      }
-    return true;
-  }
-
-  /**
-   * @return If ignore_popable_blockers is true
-   * then the result is true iff the link condition at edge ab is satisfied
-   * or equivalently iff no blocker contains ab.
-   * If ignore_popable_blockers is false then the
-   * result is true iff all blocker containing ab are popable.
-   */
-  bool link_condition(Edge_handle & e,
-                      bool ignore_popable_blockers = false) const {
-    const Graph_edge& edge = (*this)[e];
-    assert(this->get_address(edge.first()));
-    assert(this->get_address(edge.second()));
-    Vertex_handle a(*this->get_address(edge.first()));
-    Vertex_handle b(*this->get_address(edge.second()));
-    return link_condition(a, b, ignore_popable_blockers);
-  }
-
- protected:
-  /**
-   * Compute simplices beta such that a.beta is an order 0 blocker
-   * that may be used to construct a new blocker after contracting ab.
-   * Suppose that the link condition Link(ab) = Link(a) inter Link(b)
-   * is satisfied.
-   */
-  void tip_blockers(Vertex_handle a, Vertex_handle b,
-                    std::vector<Simplex_handle> & buffer) const {
-    for (auto const & blocker : this->const_blocker_range(a)) {
-      Simplex_handle beta = (*blocker);
-      beta.remove_vertex(a);
-      buffer.push_back(beta);
-    }
-
-    Simplex_handle n;
-    this->add_neighbours(b, n);
-    this->remove_neighbours(a, n);
-    n.remove_vertex(a);
-
-    for (Vertex_handle y : n) {
-      Simplex_handle beta;
-      beta.add_vertex(y);
-      buffer.push_back(beta);
-    }
-  }
-
- private:
-  /**
-   * @brief "Replace" the edge 'bx' by the edge 'ax'.
-   * Assume that the edge 'bx' was present whereas 'ax' was not.
-   * Precisely, it does not replace edges, but remove 'bx' and then add 'ax'.
-   * The visitor 'on_swaped_edge' is called just after edge 'ax' had been added
-   * and just before edge 'bx' had been removed. That way, it can
-   * eventually access to information of 'ax'.
-   */
-  void swap_edge(Vertex_handle a, Vertex_handle b, Vertex_handle x) {
-    this->add_edge(a, x);
-    if (this->visitor)
-      this->visitor->on_swaped_edge(a, b, x);
-    this->remove_edge(b, x);
-  }
-
- private:
-  /**
-   * @brief removes all blockers passing through the edge 'ab'
-   */
-  void delete_blockers_around_vertex(Vertex_handle v) {
-    std::list < Blocker_handle > blockers_to_delete;
-    for (auto blocker : this->blocker_range(v)) {
-      blockers_to_delete.push_back(blocker);
-    }
-    while (!blockers_to_delete.empty()) {
-      this->remove_blocker(blockers_to_delete.back());
-      blockers_to_delete.pop_back();
-    }
-  }
-  /**
-   * @brief removes all blockers passing through the edge 'ab'
-   */
-  void delete_blockers_around_edge(Vertex_handle a, Vertex_handle b) {
-    std::list < Blocker_handle > blocker_to_delete;
-    for (auto blocker : this->blocker_range(a))
-      if (blocker->contains(b))
-        blocker_to_delete.push_back(blocker);
-    while (!blocker_to_delete.empty()) {
-      this->delete_blocker(blocker_to_delete.back());
-      blocker_to_delete.pop_back();
-    }
-  }
-
- public:
-  /**
-   * Contracts the edge.
-   * @remark If the link condition Link(ab) = Link(a) inter Link(b) is not satisfied,
-   * it removes first all blockers passing through 'ab'
-   */
-  void contract_edge(Edge_handle edge) {
-    contract_edge(this->first_vertex(edge), this->second_vertex(edge));
-  }
-
-  /**
-   * Contracts the edge connecting vertices a and b.
-   * @remark If the link condition Link(ab) = Link(a) inter Link(b) is not satisfied,
-   * it removes first all blockers passing through 'ab'
-   */
-  void contract_edge(Vertex_handle a, Vertex_handle b) {
-    assert(this->contains_vertex(a));
-    assert(this->contains_vertex(b));
-    assert(this->contains_edge(a, b));
-
-    // if some blockers passes through 'ab', we remove them.
-    if (!link_condition(a, b))
-      delete_blockers_around_edge(a, b);
-
-    std::set < Simplex_handle > blockers_to_add;
-
-    get_blockers_to_be_added_after_contraction(a, b, blockers_to_add);
-
-    delete_blockers_around_vertices(a, b);
-
-    update_edges_after_contraction(a, b);
-
-    this->remove_vertex(b);
-
-    notify_changed_edges(a);
-
-    for (auto block : blockers_to_add)
-      this->add_blocker(block);
-
-    assert(this->contains_vertex(a));
-    assert(!this->contains_vertex(b));
-  }
-
- private:
-  void get_blockers_to_be_added_after_contraction(
-      Vertex_handle a, Vertex_handle b,
-      std::set<Simplex_handle>& blockers_to_add) {
-    blockers_to_add.clear();
-
-    typedef Skeleton_blocker_link_complex<
-        Skeleton_blocker_complex<SkeletonBlockerDS> > LinkComplexType;
-
-    LinkComplexType link_a(*this, a);
-    LinkComplexType link_b(*this, b);
-
-    std::vector < Simplex_handle > vector_alpha, vector_beta;
-
-    tip_blockers(a, b, vector_alpha);
-    tip_blockers(b, a, vector_beta);
-
-    for (auto alpha = vector_alpha.begin(); alpha != vector_alpha.end();
-        ++alpha) {
-      for (auto beta = vector_beta.begin(); beta != vector_beta.end(); ++beta) {
-        Simplex_handle sigma = *alpha;
-        sigma.union_vertices(*beta);
-        Root_simplex_handle sigma_id = this->get_id(sigma);
-        if (this->contains(sigma)
-            && proper_faces_in_union<SkeletonBlockerComplex>(sigma_id, link_a,
-                                                             link_b)) {
-          // Blocker_handle blocker = new Simplex_handle(sigma);
-          sigma.add_vertex(a);
-          blockers_to_add.insert(sigma);
-        }
-      }
-    }
-  }
-
-  /**
-   * delete all blockers that passes through a or b
-   */
-  void delete_blockers_around_vertices(Vertex_handle a, Vertex_handle b) {
-    std::vector < Blocker_handle > blocker_to_delete;
-    for (auto bl : this->blocker_range(a))
-      blocker_to_delete.push_back(bl);
-    for (auto bl : this->blocker_range(b))
-      blocker_to_delete.push_back(bl);
-    while (!blocker_to_delete.empty()) {
-      this->delete_blocker(blocker_to_delete.back());
-      blocker_to_delete.pop_back();
-    }
-  }
-
-  void update_edges_after_contraction(Vertex_handle a, Vertex_handle b) {
-    // We update the set of edges
-    this->remove_edge(a, b);
-
-    // For all edges {b,x} incident to b,
-    // we remove {b,x} and add {a,x} if not already there.
-    while (this->degree(b) > 0) {
-      Vertex_handle x(*(adjacent_vertices(b.vertex, this->skeleton).first));
-      if (!this->contains_edge(a, x))
-        // we 'replace' the edge 'bx' by the edge 'ax'
-        this->swap_edge(a, b, x);
-      else
-        this->remove_edge(b, x);
-    }
-  }
-
-  void notify_changed_edges(Vertex_handle a) {
-    // We notify the visitor that all edges incident to 'a' had changed
-    boost_adjacency_iterator v, v_end;
-
-    for (tie(v, v_end) = adjacent_vertices(a.vertex, this->skeleton);
-        v != v_end; ++v)
-      if (this->visitor)
-        this->visitor->on_changed_edge(a, Vertex_handle(*v));
-  }
-
-  //@}
+class Skeleton_blocker_simplifiable_complex : public Skeleton_blocker_complex<SkeletonBlockerDS>
+{
+	template<class ComplexType> friend class Skeleton_blocker_sub_complex;
+
+public:
+
+	typedef Skeleton_blocker_complex<SkeletonBlockerDS> SkeletonBlockerComplex;
+
+	typedef typename SkeletonBlockerComplex::Graph_edge Graph_edge;
+
+	typedef typename SkeletonBlockerComplex::boost_adjacency_iterator boost_adjacency_iterator;
+	typedef typename SkeletonBlockerComplex::Edge_handle Edge_handle;
+	typedef typename SkeletonBlockerComplex::boost_vertex_handle boost_vertex_handle;
+	typedef typename SkeletonBlockerComplex::Vertex_handle Vertex_handle;
+	typedef typename SkeletonBlockerComplex::Root_vertex_handle Root_vertex_handle;
+	typedef typename SkeletonBlockerComplex::Simplex_handle Simplex_handle;
+	typedef typename SkeletonBlockerComplex::Root_simplex_handle Root_simplex_handle;
+	typedef typename SkeletonBlockerComplex::Blocker_handle Blocker_handle;
+
+
+	typedef typename SkeletonBlockerComplex::Root_simplex_iterator Root_simplex_iterator;
+	typedef typename SkeletonBlockerComplex::Simplex_handle_iterator Simplex_handle_iterator;
+	typedef typename SkeletonBlockerComplex::BlockerMap BlockerMap;
+	typedef typename SkeletonBlockerComplex::BlockerPair BlockerPair;
+	typedef typename SkeletonBlockerComplex::BlockerMapIterator BlockerMapIterator;
+	typedef typename SkeletonBlockerComplex::BlockerMapConstIterator BlockerMapConstIterator;
+
+	typedef typename SkeletonBlockerComplex::Visitor Visitor;
+
+
+	/** @name Constructors / Destructors / Initialization
+	 */
+	//@{
+	Skeleton_blocker_simplifiable_complex(int num_vertices_ = 0,Visitor* visitor_=NULL):
+		Skeleton_blocker_complex<SkeletonBlockerDS>(num_vertices_,visitor_){	}
+
+
+	/**
+	 * @brief Constructor with a list of simplices
+	 * @details The list of simplices must be the list
+	 * of simplices of a simplicial complex, sorted with increasing dimension.
+	 * todo take iterator instead
+	 */
+	Skeleton_blocker_simplifiable_complex(std::list<Simplex_handle>& simplices,Visitor* visitor_=NULL):
+		Skeleton_blocker_complex<SkeletonBlockerDS>(simplices,visitor_)
+		{}
+
+
+
+	virtual ~Skeleton_blocker_simplifiable_complex(){
+	}
+
+	//@}
+
+	/**
+	 * Returns true iff the blocker 'sigma' is popable.
+	 * To define popable, let us call 'L' the complex that
+	 * consists in the current complex without the blocker 'sigma'.
+	 * A blocker 'sigma' is then "popable" if the link of 'sigma'
+	 * in L is reducible.
+	 *
+	 */
+	virtual bool is_popable_blocker(Blocker_handle sigma) const{
+		assert(this->contains_blocker(*sigma));
+		Skeleton_blocker_link_complex<Skeleton_blocker_simplifiable_complex> link_blocker_sigma;
+		build_link_of_blocker(*this,*sigma,link_blocker_sigma);
+
+		bool res = link_blocker_sigma.is_contractible()==CONTRACTIBLE;
+		return res;
+	}
+
+
+	/**
+	 * Removes all the popable blockers of the complex and delete them.
+	 * @returns the number of popable blockers deleted
+	 */
+	void remove_popable_blockers(){
+		std::list<Vertex_handle> vertex_to_check;
+		for(auto v : this->vertex_range())
+			vertex_to_check.push_front(v);
+
+		while(!vertex_to_check.empty()){
+			Vertex_handle v = vertex_to_check.front();
+			vertex_to_check.pop_front();
+
+			bool blocker_popable_found=true;
+			while (blocker_popable_found){
+				blocker_popable_found = false;
+				for(auto block : this->blocker_range(v)){
+					if (this->is_popable_blocker(block)) {
+						for(Vertex_handle nv : *block)
+							if(nv!=v) vertex_to_check.push_back(nv);
+						this->delete_blocker(block);
+						blocker_popable_found = true;
+						break;
+					}
+				}
+			}
+		}
+	}
+
+	/**
+	 * Removes all the popable blockers of the complex passing through v and delete them.
+	 */
+	void remove_popable_blockers(Vertex_handle v){
+		bool blocker_popable_found=true;
+		while (blocker_popable_found){
+			blocker_popable_found = false;
+			for(auto block : this->blocker_range(v)){
+				if (is_popable_blocker(block)) {
+					this->delete_blocker(block);
+					blocker_popable_found = true;
+				}
+			}
+		}
+	}
+
+	/**
+	 * @brief Removes all the popable blockers of the complex passing through v and delete them.
+	 * Also remove popable blockers in the neighborhood if they became popable.
+	 *
+	 */
+	void remove_all_popable_blockers(Vertex_handle v){
+		std::list<Vertex_handle> vertex_to_check;
+		vertex_to_check.push_front(v);
+
+		while(!vertex_to_check.empty()){
+			Vertex_handle v = vertex_to_check.front();
+			vertex_to_check.pop_front();
+
+			bool blocker_popable_found=true;
+			while (blocker_popable_found){
+				blocker_popable_found = false;
+				for(auto block : this->blocker_range(v)){
+					if (this->is_popable_blocker(block)) {
+						for(Vertex_handle nv : *block)
+							if(nv!=v) vertex_to_check.push_back(nv);
+						this->delete_blocker(block);
+						blocker_popable_found = true;
+						break;
+					}
+				}
+			}
+		}
+	}
+
+	/**
+	 * Remove the star of the vertex 'v'
+	 */
+	void remove_star(Vertex_handle v){
+		// we remove the blockers that are not consistent anymore
+		update_blockers_after_remove_star_of_vertex_or_edge(Simplex_handle(v));
+		while (this->degree(v) > 0){
+			Vertex_handle w( * (adjacent_vertices(v.vertex, this->skeleton).first));
+			this->remove_edge(v,w);
+		}
+		this->remove_vertex(v);
+	}
+
+private:
+	/**
+	 * after removing the star of a simplex, blockers sigma that contains this simplex must be removed.
+	 * Furthermore, all simplices tau of the form sigma \setminus simplex_to_be_removed must be added
+	 * whenever the dimension of tau is at least 2.
+	 */
+	void update_blockers_after_remove_star_of_vertex_or_edge(const Simplex_handle& simplex_to_be_removed){
+		std::list <Blocker_handle> blockers_to_update;
+		if(simplex_to_be_removed.empty()) return;
+
+		auto v0 = simplex_to_be_removed.first_vertex();
+		for (auto blocker : this->blocker_range(v0)){
+			if(blocker->contains(simplex_to_be_removed))
+				blockers_to_update.push_back(blocker);
+		}
+
+		for(auto blocker_to_update : blockers_to_update){
+			Simplex_handle sub_blocker_to_be_added;
+			bool sub_blocker_need_to_be_added =
+					(blocker_to_update->dimension()-simplex_to_be_removed.dimension()) >= 2;
+			if(sub_blocker_need_to_be_added){
+				sub_blocker_to_be_added = *blocker_to_update;
+				sub_blocker_to_be_added.difference(simplex_to_be_removed);
+			}
+			this->delete_blocker(blocker_to_update);
+			if(sub_blocker_need_to_be_added)
+				this->add_blocker(sub_blocker_to_be_added);
+		}
+	}
+
+
+
+public:
+	/**
+	 * Remove the star of the edge connecting vertices a and b.
+	 * @returns the number of blocker that have been removed
+	 */
+	void remove_star(Vertex_handle a, Vertex_handle b){
+		update_blockers_after_remove_star_of_vertex_or_edge(Simplex_handle(a,b));
+		// we remove the edge
+		this->remove_edge(a,b);
+	}
+
+
+	/**
+	 * Remove the star of the edge 'e'.
+	 */
+	void remove_star(Edge_handle e){
+		return remove_star(this->first_vertex(e),this->second_vertex(e));
+	}
+
+	/**
+	 * Remove the star of the simplex 'sigma' which needs to belong to the complex
+	 */
+	void remove_star(const Simplex_handle& sigma){
+		assert(this->contains(sigma));
+		if (sigma.dimension()==0)
+			remove_star(sigma.first_vertex());
+		else
+			if (sigma.dimension()==1)
+				remove_star(sigma.first_vertex(),sigma.last_vertex());
+			else{
+				remove_blocker_containing_simplex(sigma);
+				this->add_blocker(sigma);
+			}
+	}
+
+	/**
+	 * @brief add a maximal simplex plus all its cofaces.
+	 * @details the simplex must have dimension greater than one (otherwise use add_vertex or add_edge).
+	 */
+	void add_simplex(const Simplex_handle& sigma){
+		assert(!this->contains(sigma));
+		assert(sigma.dimension()>1);
+		remove_blocker_include_in_simplex(sigma);
+	}
+
+private:
+	/**
+	 * remove all blockers that contains sigma
+	 */
+	void remove_blocker_containing_simplex(const Simplex_handle& sigma){
+		std::vector <Blocker_handle> blockers_to_remove;
+		for (auto blocker : this->blocker_range(sigma.first_vertex())){
+			if(blocker->contains(sigma))
+				blockers_to_remove.push_back(blocker);
+		}
+		for(auto blocker_to_update : blockers_to_remove)
+			this->delete_blocker(blocker_to_update);
+	}
+
+	/**
+	 * remove all blockers that contains sigma
+	 */
+	void remove_blocker_include_in_simplex(const Simplex_handle& sigma){
+		std::vector <Blocker_handle> blockers_to_remove;
+		for (auto blocker : this->blocker_range(sigma.first_vertex())){
+			if(sigma.contains(*blocker))
+				blockers_to_remove.push_back(blocker);
+		}
+		for(auto blocker_to_update : blockers_to_remove)
+			this->delete_blocker(blocker_to_update);
+	}
+
+
+public:
+
+	enum simplifiable_status{ NOT_HOMOTOPY_EQ,MAYBE_HOMOTOPY_EQ,HOMOTOPY_EQ};
+	simplifiable_status is_remove_star_homotopy_preserving(const Simplex_handle& simplex){
+		//todo write a virtual method 'link' in Skeleton_blocker_complex which will be overloaded by the current one of Skeleton_blocker_geometric_complex
+		//then call it there to build the link and return the value of link.is_contractible()
+		return MAYBE_HOMOTOPY_EQ;
+	}
+
+
+
+	enum contractible_status{ NOT_CONTRACTIBLE,MAYBE_CONTRACTIBLE,CONTRACTIBLE};
+	/**
+	 * @brief %Test if the complex is reducible using a strategy defined in the class
+	 * (by default it tests if the complex is a cone)
+	 * @details Note that NO could be returned if some invariant ensures that the complex
+	 * is not a point (for instance if the euler characteristic is different from 1).
+	 * This function will surely have to return MAYBE in some case because the
+	 * associated problem is undecidable but it in practice, it can often
+	 * be solved with the help of geometry.
+	 */
+	virtual contractible_status is_contractible() const{
+		if (this->is_cone()) return CONTRACTIBLE;
+		else return MAYBE_CONTRACTIBLE;
+	}
+
+
+	/** @Edge contraction operations
+	 */
+	//@{
+
+
+
+	/**
+	 * @return If ignore_popable_blockers is true
+	 * then the result is true iff the link condition at edge ab is satisfied
+	 * or equivalently iff no blocker contains ab.
+	 * If ignore_popable_blockers is false then the
+	 * result is true iff all blocker containing ab are popable.
+	 */
+	bool link_condition(Vertex_handle a, Vertex_handle b,bool ignore_popable_blockers = false) const{
+		for (auto blocker : this->const_blocker_range(a))
+			if ( blocker->contains(b) ){
+				// false if ignore_popable_blockers is false
+				// otherwise the blocker has to be popable
+				return ignore_popable_blockers && is_popable_blocker(blocker);
+			}
+		return true;
+	}
+
+	/**
+	 * @return If ignore_popable_blockers is true
+	 * then the result is true iff the link condition at edge ab is satisfied
+	 * or equivalently iff no blocker contains ab.
+	 * If ignore_popable_blockers is false then the
+	 * result is true iff all blocker containing ab are popable.
+	 */
+	bool link_condition(Edge_handle & e,bool ignore_popable_blockers = false) const{
+		const Graph_edge& edge = (*this)[e];
+		assert(this->get_address(edge.first()));
+		assert(this->get_address(edge.second()));
+		Vertex_handle a(*this->get_address(edge.first()));
+		Vertex_handle b(*this->get_address(edge.second()));
+		return link_condition(a,b,ignore_popable_blockers);
+	}
+
+
+protected:
+	/**
+	 * Compute simplices beta such that a.beta is an order 0 blocker
+	 * that may be used to construct a new blocker after contracting ab.
+	 * It requires that the link condition is satisfied.
+	 */
+	void tip_blockers(Vertex_handle a, Vertex_handle b, std::vector<Simplex_handle> & buffer) const{
+		for (auto const & blocker : this->const_blocker_range(a))
+		{
+			Simplex_handle beta = (*blocker);
+			beta.remove_vertex(a);
+			buffer.push_back(beta);
+		}
+
+		Simplex_handle n;
+		this->add_neighbours(b,n);
+		this->remove_neighbours(a,n);
+		n.remove_vertex(a);
+
+
+		for (Vertex_handle y : n)
+		{
+			Simplex_handle beta;
+			beta.add_vertex( y );
+			buffer.push_back(beta);
+		}
+	}
+
+
+private:
+
+	/**
+	 * @brief "Replace" the edge 'bx' by the edge 'ax'.
+	 * Assume that the edge 'bx' was present whereas 'ax' was not.
+	 * Precisely, it does not replace edges, but remove 'bx' and then add 'ax'.
+	 * The visitor 'on_swaped_edge' is called just after edge 'ax' had been added
+	 * and just before edge 'bx' had been removed. That way, it can
+	 * eventually access to information of 'ax'.
+	 */
+	void swap_edge(Vertex_handle a,Vertex_handle b,Vertex_handle x){
+		this->add_edge(a,x);
+		if (this->visitor) this->visitor->on_swaped_edge(a,b,x);
+		this->remove_edge(b,x);
+	}
+
+
+private:
+	/**
+	 * @brief removes all blockers passing through the edge 'ab'
+	 */
+	void delete_blockers_around_vertex(Vertex_handle v){
+		std::list <Blocker_handle> blockers_to_delete;
+		for (auto blocker : this->blocker_range(v)){
+			blockers_to_delete.push_back(blocker);
+		}
+		while (!blockers_to_delete.empty()){
+			this->remove_blocker(blockers_to_delete.back());
+			blockers_to_delete.pop_back();
+		}
+
+	}
+	/**
+	 * @brief removes all blockers passing through the edge 'ab'
+	 */
+	void delete_blockers_around_edge(Vertex_handle a, Vertex_handle b){
+		std::list<Blocker_handle> blocker_to_delete;
+		for (auto blocker : this->blocker_range(a))
+			if (blocker->contains(b)) blocker_to_delete.push_back(blocker);
+		while (!blocker_to_delete.empty())
+		{
+			this->delete_blocker(blocker_to_delete.back());
+			blocker_to_delete.pop_back();
+		}
+	}
+
+public:
+
+	/**
+	 * Contracts the edge.
+	 * @remark If the link condition Link(ab) = Link(a) inter Link(b) is not satisfied,
+	 * it removes first all blockers passing through 'ab'
+	 */
+	void contract_edge(Edge_handle edge){
+		contract_edge(this->first_vertex(edge),this->second_vertex(edge));
+	}
+
+
+	/**
+	 * Contracts the edge connecting vertices a and b.
+	 * @remark If the link condition Link(ab) = Link(a) inter Link(b) is not satisfied,
+	 * it removes first all blockers passing through 'ab'
+	 */
+	void contract_edge(Vertex_handle a, Vertex_handle b){
+		assert(this->contains_vertex(a));
+		assert(this->contains_vertex(b));
+		assert(this->contains_edge(a,b));
+
+		// if some blockers passes through 'ab', we remove them.
+		if (!link_condition(a,b))
+			delete_blockers_around_edge(a,b);
+
+		std::set<Simplex_handle> blockers_to_add;
+
+		get_blockers_to_be_added_after_contraction(a,b,blockers_to_add);
+
+		delete_blockers_around_vertices(a,b);
+
+		update_edges_after_contraction(a,b);
+
+		this->remove_vertex(b);
+
+		notify_changed_edges(a);
+
+		for(auto block : blockers_to_add)
+			this->add_blocker(block);
+
+		assert(this->contains_vertex(a));
+		assert(!this->contains_vertex(b));
+	}
+
+
+private:
+
+	void get_blockers_to_be_added_after_contraction(Vertex_handle a,Vertex_handle b,std::set<Simplex_handle>& blockers_to_add){
+		blockers_to_add.clear();
+
+		typedef Skeleton_blocker_link_complex<Skeleton_blocker_complex<SkeletonBlockerDS> > LinkComplexType;
+
+		LinkComplexType link_a(*this,a);
+		LinkComplexType link_b(*this,b);
+
+		std::vector<Simplex_handle> vector_alpha, vector_beta;
+
+		tip_blockers(a,b,vector_alpha);
+		tip_blockers(b,a,vector_beta);
+
+		for (auto alpha = vector_alpha.begin(); alpha != vector_alpha.end(); ++alpha){
+			for (auto beta = vector_beta.begin(); beta != vector_beta.end(); ++beta)
+			{
+				Simplex_handle sigma = *alpha; sigma.union_vertices(*beta);
+				Root_simplex_handle sigma_id = this->get_id(sigma);
+				if ( this->contains(sigma) &&
+						proper_faces_in_union<SkeletonBlockerComplex>(sigma_id,link_a,link_b))
+				{
+					//					Blocker_handle blocker = new Simplex_handle(sigma);
+					sigma.add_vertex(a);
+					blockers_to_add.insert(sigma);
+				}
+			}
+		}
+	}
+
+
+	/**
+	 * delete all blockers that passes through a or b
+	 */
+	void delete_blockers_around_vertices(Vertex_handle a,Vertex_handle b){
+		std::vector<Blocker_handle> blocker_to_delete;
+		for(auto bl : this->blocker_range(a))
+			blocker_to_delete.push_back(bl);
+		for(auto bl : this->blocker_range(b))
+			blocker_to_delete.push_back(bl);
+		while (!blocker_to_delete.empty())
+		{
+			this->delete_blocker(blocker_to_delete.back());
+			blocker_to_delete.pop_back();
+		}
+	}
+
+
+	void update_edges_after_contraction(Vertex_handle a,Vertex_handle b){
+		// We update the set of edges
+		this->remove_edge(a,b);
+
+		// For all edges {b,x} incident to b,
+		// we remove {b,x} and add {a,x} if not already there.
+		while (this->degree(b)> 0)
+		{
+			Vertex_handle x(*(adjacent_vertices(b.vertex, this->skeleton).first));
+			if(!this->contains_edge(a,x))
+				// we 'replace' the edge 'bx' by the edge 'ax'
+				this->swap_edge(a,b,x);
+			else
+				this->remove_edge(b,x);
+		}
+	}
+
+	void notify_changed_edges(Vertex_handle a){
+		// We notify the visitor that all edges incident to 'a' had changed
+		boost_adjacency_iterator v, v_end;
+
+		for (tie(v, v_end) = adjacent_vertices(a.vertex, this->skeleton); v != v_end; ++v)
+			if (this->visitor) this->visitor->on_changed_edge(a,Vertex_handle(*v));
+	}
+
+	//@}
+
+
 };
 
-}  // namespace skbl
+}
 
-}  // namespace Gudhi
+}  // namespace GUDHI
 
-#endif  // SRC_SKELETON_BLOCKER_INCLUDE_GUDHI_SKELETON_BLOCKER_SIMPLIFIABLE_COMPLEX_H_
+#endif /* GUDHI_SKELETON_BLOCKERS_SIMPLIFIABLE_COMPLEX_H_ */