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diff --git a/src/GudhUI/utils/Is_manifold.h b/src/GudhUI/utils/Is_manifold.h
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+++ b/src/GudhUI/utils/Is_manifold.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):       David Salinas
+ *
+ *    Copyright (C) 2014 Inria
+ *
+ *    Modification(s):
+ *      - YYYY/MM Author: Description of the modification
+ */
+
+
+#ifndef UTILS_IS_MANIFOLD_H_
+#define UTILS_IS_MANIFOLD_H_
+
+#include "utils/UI_utils.h"
+#include "utils/Edge_contractor.h"
+
+/**
+ * Iteratively tries to anticollapse smallest edge non added so far.
+ * If its link is contractible then no topological change and else possible topological change.
+ *
+ * todo do a sparsification with some parameter eps while growing
+ */
+template<typename SkBlComplex> class Is_manifold {
+ private:
+  const SkBlComplex& input_complex_;
+  typedef typename SkBlComplex::Vertex_handle Vertex_handle;
+
+ public:
+  /*
+   * return dim the maximum dimension around one simplex and res which is true if the complex is a manifold.
+   * If the complex has dimension <= 3 then if res is false, the complex is not a manifold.
+   * For d-manifold with d>=4, res may be false while the complex is a manifold.
+   */
+  Is_manifold(const SkBlComplex& input_complex, unsigned& dim, bool & res) : input_complex_(input_complex) {
+    res = true;
+    dim = -1;
+    if (!input_complex_.empty()) {
+      for (auto v : input_complex_.vertex_range()) {
+        dim = local_dimension(v);
+        break;
+      }
+      // check that the link of every vertex is a dim-1 sphere
+      for (auto v : input_complex_.vertex_range()) {
+        if (!is_k_sphere(v, dim - 1)) {
+          res = false;
+          break;
+        }
+      }
+    }
+  }
+
+ private:
+  unsigned local_dimension(Vertex_handle v) {
+    unsigned dim = 0;
+    for (const auto& s : input_complex_.star_simplex_range(v))
+      dim = (std::max)(dim, (unsigned) s.dimension());
+    return dim;
+  }
+
+  bool is_k_sphere(Vertex_handle v, int k) {
+    auto link = input_complex_.link(v);
+    Edge_contractor<Complex> contractor(link, link.num_vertices() - 1);
+    (void)contractor;
+    return (is_sphere_simplex(link) == k);
+  }
+
+  // A minimal sphere is a complex that contains vertices v1...vn and all faces
+  // made upon this set except the face {v1,...,vn}
+  // return -2 if not a minimal sphere
+  // and d otherwise if complex is a d minimal sphere
+
+  template<typename SubComplex>
+  int is_sphere_simplex(const SubComplex& complex) {
+    if (complex.empty()) return -1;
+    if (complex.num_blockers() != 1) return -2;
+
+    // necessary and sufficient condition : there exists a unique blocker that passes through all vertices
+    auto first_blocker = *(complex.const_blocker_range().begin());
+
+    if (first_blocker->dimension() + 1 != complex.num_vertices())
+      return -2;
+    else
+      return (first_blocker->dimension() - 1);
+  }
+};
+
+#endif  // UTILS_IS_MANIFOLD_H_