5 files changed, 103 insertions, 0 deletions
diff --git a/src/Simplex_tree/concept/FiltrationValue.h b/src/Simplex_tree/concept/FiltrationValue.h
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+++ b/src/Simplex_tree/concept/FiltrationValue.h
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+/*    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):       Clément Maria
+ *
+ *    Copyright (C) 2014 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+/** \brief Value type for a filtration function on a cell complex.
+  *
+  * A <EM>filtration</EM> of a cell complex (see FilteredComplex) is
+  * a function \f$f:\mathbf{K} \rightarrow \mathbb{R}\f$ satisfying \f$f(\tau)\leq 
+  * f(\sigma)\f$ whenever \f$\tau \subseteq \sigma\f$. Ordering the simplices 
+  * by increasing filtration values (breaking ties so as a simplex appears after 
+  * its subsimplices of same filtration value) provides an indexing scheme 
+  * (see IndexingTag).
+  */
+  struct FiltrationValue {
+    /** \brief Operator < is a StrictWeakOrdering. */
+    bool operator<(FiltrationValue f1, FiltrationValue f2);
+  };
diff --git a/src/Simplex_tree/concept/IndexingTag.h b/src/Simplex_tree/concept/IndexingTag.h
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+++ b/src/Simplex_tree/concept/IndexingTag.h
@@ -0,0 +1,18 @@
+/*    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):       Clément Maria
+ *
+ *    Copyright (C) 2014 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+/** \brief Concept describing an indexing scheme (see FilteredComplex) 
+  * for applying 
+  * continuous maps to a cell complex, and compute its persistent
+  * homology.
+  *
+  * Must be `Gudhi::linear_indexing_tag`. 
+  */
+struct IndexingTag {};
diff --git a/src/Simplex_tree/concept/SimplexKey.h b/src/Simplex_tree/concept/SimplexKey.h
new file mode 100644
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+++ b/src/Simplex_tree/concept/SimplexKey.h
@@ -0,0 +1,16 @@
+/*    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):       Clément Maria
+ *
+ *    Copyright (C) 2014 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+ /** \brief Key type used as simplex identifier.
+  *
+  * Must be an integer type.
+  */
+ struct SimplexKey {};
+ 
diff --git a/src/Simplex_tree/concept/SimplexTreeOptions.h b/src/Simplex_tree/concept/SimplexTreeOptions.h
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+++ b/src/Simplex_tree/concept/SimplexTreeOptions.h
@@ -0,0 +1,31 @@
+/*    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):       Marc Glisse
+ *
+ *    Copyright (C) 2015 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+  
+/** \brief Concept of the template parameter for the class `Gudhi::Simplex_tree<SimplexTreeOptions>`.
+ *
+ * One model for this is `Gudhi::Simplex_tree_options_full_featured`. If you want to provide your own, it is recommended that you derive from it and override some parts instead of writing a class from scratch.
+ */
+struct SimplexTreeOptions {
+  /// Forced for now.
+  typedef IndexingTag Indexing_tag;
+  /// Must be a signed integer type. It admits a total order <.
+  typedef VertexHandle Vertex_handle;
+  /// Must be comparable with operator<.
+  typedef FiltrationValue Filtration_value;
+  /// Must be an integer type.
+  typedef SimplexKey Simplex_key;
+  /// If true, each simplex has extra storage for one `Simplex_key`. Necessary for `Persistent_cohomology`.
+  static const bool store_key;
+  /// If true, each simplex has extra storage for one `Filtration_value`, and this value is propagated by operations like `Gudhi::Simplex_tree::expansion`. Without it, `Persistent_cohomology` degenerates to computing usual (non-persistent) cohomology.
+  static const bool store_filtration;
+  /// If true, the list of vertices present in the complex must always be 0, ..., num_vertices-1, without any hole.
+  static constexpr bool contiguous_vertices;
+};
+
diff --git a/src/Simplex_tree/concept/VertexHandle.h b/src/Simplex_tree/concept/VertexHandle.h
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+++ b/src/Simplex_tree/concept/VertexHandle.h
@@ -0,0 +1,15 @@
+/*    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):       Clément Maria
+ *
+ *    Copyright (C) 2014 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+  
+/** \brief Handle type for the vertices of a cell complex.
+  * 
+  * Must be a signed integer type. <code>operator&lt;</code> defines a total order on it.
+  */
+struct VertexHandle {};