1 files changed, 20 insertions, 6 deletions

diff --git a/include/gudhi/Persistent_cohomology.h b/include/gudhi/Persistent_cohomology.h
index b31df6a4..672fda48 100644
--- a/include/gudhi/Persistent_cohomology.h
+++ b/include/gudhi/Persistent_cohomology.h
@@ -110,7 +110,7 @@ class Persistent_cohomology {
         cell_pool_() {
     if (cpx_->num_simplices() > std::numeric_limits<Simplex_key>::max()) {
       // num_simplices must be strictly lower than the limit, because a value is reserved for null_key.
-      throw std::out_of_range ("The number of simplices is more than Simplex_key type numeric limit.");
+      throw std::out_of_range("The number of simplices is more than Simplex_key type numeric limit.");
     }
     Simplex_key idx_fil = 0;
     for (auto sh : cpx_->filtration_simplex_range()) {
@@ -300,8 +300,7 @@ class Persistent_cohomology {
     // with multiplicity. We used to sum the coefficients directly in
     // annotations_in_boundary by using a map, we now do it later.
     typedef std::pair<Column *, int> annotation_t;
-    // Danger: not thread-safe!
-    static std::vector<annotation_t> annotations_in_boundary;
+    thread_local std::vector<annotation_t> annotations_in_boundary;
     annotations_in_boundary.clear();
     int sign = 1 - 2 * (dim_sigma % 2);  // \in {-1,1} provides the sign in the
                                          // alternate sum in the boundary.
@@ -604,7 +603,7 @@ class Persistent_cohomology {
    */
   std::vector<int> betti_numbers() const {
     // Init Betti numbers vector with zeros until Simplicial complex dimension
-    std::vector<int> betti_numbers(cpx_->dimension(), 0);
+    std::vector<int> betti_numbers(dim_max_, 0);
 
     for (auto pair : persistent_pairs_) {
       // Count never ended persistence intervals
@@ -643,8 +642,7 @@ class Persistent_cohomology {
    */
   std::vector<int> persistent_betti_numbers(Filtration_value from, Filtration_value to) const {
     // Init Betti numbers vector with zeros until Simplicial complex dimension
-    std::vector<int> betti_numbers(cpx_->dimension(), 0);
-
+    std::vector<int> betti_numbers(dim_max_, 0);
     for (auto pair : persistent_pairs_) {
       // Count persistence intervals that covers the given interval
       // null_simplex test : if the function is called with to=+infinity, we still get something useful. And it will
@@ -690,6 +688,22 @@ class Persistent_cohomology {
     return persistent_pairs_;
   }
 
+  /** @brief Returns persistence intervals for a given dimension.
+   * @param[in] dimension Dimension to get the birth and death pairs from.
+   * @return A vector of persistence intervals (birth and death) on a fixed dimension.
+   */
+  std::vector< std::pair< Filtration_value , Filtration_value > >
+  intervals_in_dimension(int dimension) {
+    std::vector< std::pair< Filtration_value , Filtration_value > > result;
+    // auto && pair, to avoid unnecessary copying
+    for (auto && pair : persistent_pairs_) {
+      if (cpx_->dimension(get<0>(pair)) == dimension) {
+        result.emplace_back(cpx_->filtration(get<0>(pair)), cpx_->filtration(get<1>(pair)));
+      }
+    }
+    return result;
+  }
+
  private:
   /*
    * Structure representing a cocycle.