1 files changed, 61 insertions, 0 deletions
diff --git a/src/Skeleton_blocker/include/gudhi/Skeleton_blocker/internal/Top_faces.h b/src/Skeleton_blocker/include/gudhi/Skeleton_blocker/internal/Top_faces.h
new file mode 100644
index 00000000..91e79b42
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+++ b/src/Skeleton_blocker/include/gudhi/Skeleton_blocker/internal/Top_faces.h
@@ -0,0 +1,61 @@
+/*    This file is part of the Gudhi Library - https://gudhi.inria.fr/ - which is released under MIT.
+ *    See file LICENSE or go to https://gudhi.inria.fr/licensing/ for full license details.
+ *    Author(s):       David Salinas
+ *
+ *    Copyright (C) 2014 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+#ifndef SKELETON_BLOCKER_INTERNAL_TOP_FACES_H_
+#define SKELETON_BLOCKER_INTERNAL_TOP_FACES_H_
+
+#include <list>
+#include <vector>
+#include <set>
+
+namespace Gudhi {
+
+namespace skeleton_blocker {
+
+template<typename SimplexHandle>
+std::list<SimplexHandle> subfaces(SimplexHandle top_face) {
+  std::list<SimplexHandle> res;
+  if (top_face.dimension() == -1) return res;
+  if (top_face.dimension() == 0) {
+    res.push_back(top_face);
+    return res;
+  } else {
+    auto first_vertex = top_face.first_vertex();
+    top_face.remove_vertex(first_vertex);
+    res = subfaces(top_face);
+    std::list<SimplexHandle> copy = res;
+    for (auto& simplex : copy) {
+      simplex.add_vertex(first_vertex);
+    }
+    res.push_back(SimplexHandle(first_vertex));
+    res.splice(res.end(), copy);
+    return res;
+  }
+}
+
+/**
+ * add all faces of top_face in simplices_per_dimension
+ */
+template<typename SimplexHandle>
+void register_faces(std::vector< std::set<SimplexHandle> >& simplices_per_dimension,
+                    const SimplexHandle& top_face) {
+  std::list<SimplexHandle> subfaces_list = subfaces(top_face);
+  for (auto& simplex : subfaces_list) {
+    simplices_per_dimension[simplex.dimension()].insert(simplex);
+  }
+}
+
+}  // namespace skeleton_blocker
+
+namespace skbl = skeleton_blocker;
+
+}  // namespace Gudhi
+
+#endif   // SKELETON_BLOCKER_INTERNAL_TOP_FACES_H_