New pairs in dimension function in Persistence cohomology

git-svn-id: svn+ssh://scm.gforge.inria.fr/svnroot/gudhi/trunk@1887 636b058d-ea47-450e-bf9e-a15bfbe3eedb

Former-commit-id: 76bc9a951d752a6ca0f62244012965b5b6597a17

2 files changed, 72 insertions, 0 deletions

diff --git a/src/Persistent_cohomology/include/gudhi/Persistent_cohomology.h b/src/Persistent_cohomology/include/gudhi/Persistent_cohomology.h
index b31df6a4..d3a8acc0 100644
--- a/src/Persistent_cohomology/include/gudhi/Persistent_cohomology.h
+++ b/src/Persistent_cohomology/include/gudhi/Persistent_cohomology.h
@@ -690,6 +690,21 @@ class Persistent_cohomology {
     return persistent_pairs_;
   }
 
+  /** @brief Returns persistence pairs 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 > >
+  pairs_in_dimension( unsigned dimension ) {
+    std::vector< std::pair< Filtration_value , Filtration_value > > result;
+    for (auto pair : persistent_pairs_) {
+      if (cpx_->dimension( get<0>(pair)) == dimension ) {
+        result.push_back(std::pair<Filtration_value, Filtration_value>(cpx_->filtration(get<0>(pair)),
+                                                                       cpx_->filtration(get<1>(pair))));
+      }
+    }
+    return result;
+  }
  private:
   /*
    * Structure representing a cocycle.
diff --git a/src/Persistent_cohomology/test/betti_numbers_unit_test.cpp b/src/Persistent_cohomology/test/betti_numbers_unit_test.cpp
index 40221005..67dfcce4 100644
--- a/src/Persistent_cohomology/test/betti_numbers_unit_test.cpp
+++ b/src/Persistent_cohomology/test/betti_numbers_unit_test.cpp
@@ -84,6 +84,8 @@ BOOST_AUTO_TEST_CASE( plain_homology_betti_numbers )
   // 2  1 0 inf 
   // means that in Z/2Z-homology, the Betti numbers are b0=2 and b1=1.
   
+  std::cout << "BETTI NUMBERS" << std::endl;
+
   BOOST_CHECK(pcoh.betti_number(0) == 2);
   BOOST_CHECK(pcoh.betti_number(1) == 1);
   BOOST_CHECK(pcoh.betti_number(2) == 0);
@@ -93,6 +95,8 @@ BOOST_AUTO_TEST_CASE( plain_homology_betti_numbers )
   BOOST_CHECK(bns[0] == 2);
   BOOST_CHECK(bns[1] == 1);
   BOOST_CHECK(bns[2] == 0);
+
+  std::cout << "GET PERSISTENT PAIRS" << std::endl;
   
   // Custom sort and output persistence
   cmp_intervals_by_dim_then_length<Mini_simplex_tree> cmp(&st);
@@ -115,6 +119,33 @@ BOOST_AUTO_TEST_CASE( plain_homology_betti_numbers )
   BOOST_CHECK(st.dimension(get<0>(persistent_pairs[2])) == 0);
   BOOST_CHECK(st.filtration(get<0>(persistent_pairs[2])) == 0);
   BOOST_CHECK(get<1>(persistent_pairs[2]) == st.null_simplex());
+
+  std::cout << "PAIRS IN DIMENSION" << std::endl;
+
+  auto pairs_in_dimension_0 = pcoh.pairs_in_dimension(0);
+  std::cout << "pairs_in_dimension_0.size() = " << pairs_in_dimension_0.size() << std::endl;
+  for (int i = 0; i < pairs_in_dimension_0.size(); i++)
+    std::cout << "pairs_in_dimension_0[" << i << "] = [" << pairs_in_dimension_0[i].first << "," <<
+                 pairs_in_dimension_0[i].second << "]" << std::endl;
+  BOOST_CHECK(pairs_in_dimension_0.size() == 2);
+  BOOST_CHECK(pairs_in_dimension_0[0].first == 0);
+  BOOST_CHECK(pairs_in_dimension_0[0].second == std::numeric_limits<Mini_simplex_tree::Filtration_value>::infinity());
+  BOOST_CHECK(pairs_in_dimension_0[1].first == 0);
+  BOOST_CHECK(pairs_in_dimension_0[1].second == std::numeric_limits<Mini_simplex_tree::Filtration_value>::infinity());
+
+
+  auto pairs_in_dimension_1 = pcoh.pairs_in_dimension(1);
+  std::cout << "pairs_in_dimension_1.size() = " << pairs_in_dimension_1.size() << std::endl;
+  for (int i = 0; i < pairs_in_dimension_1.size(); i++)
+    std::cout << "pairs_in_dimension_1[" << i << "] = [" << pairs_in_dimension_1[i].first << "," <<
+                 pairs_in_dimension_1[i].second << "]" << std::endl;
+  BOOST_CHECK(pairs_in_dimension_1.size() == 1);
+  BOOST_CHECK(pairs_in_dimension_1[0].first == 0);
+  BOOST_CHECK(pairs_in_dimension_1[0].second == std::numeric_limits<Mini_simplex_tree::Filtration_value>::infinity());
+
+  auto pairs_in_dimension_2 = pcoh.pairs_in_dimension(2);
+  std::cout << "pairs_in_dimension_2.size() = " << pairs_in_dimension_2.size() << std::endl;
+  BOOST_CHECK(pairs_in_dimension_2.size() == 0);
 }
 
 using Simplex_tree = Gudhi::Simplex_tree<>;
@@ -231,4 +262,30 @@ BOOST_AUTO_TEST_CASE( betti_numbers )
   BOOST_CHECK(st.dimension(get<0>(persistent_pairs[2])) == 0);
   BOOST_CHECK(st.filtration(get<0>(persistent_pairs[2])) == 1);
   BOOST_CHECK(get<1>(persistent_pairs[2]) == st.null_simplex());
+
+  std::cout << "PAIRS IN DIMENSION" << std::endl;
+
+  auto pairs_in_dimension_0 = pcoh.pairs_in_dimension(0);
+  std::cout << "pairs_in_dimension_0.size() = " << pairs_in_dimension_0.size() << std::endl;
+  for (int i = 0; i < pairs_in_dimension_0.size(); i++)
+    std::cout << "pairs_in_dimension_0[" << i << "] = [" << pairs_in_dimension_0[i].first << "," <<
+                 pairs_in_dimension_0[i].second << "]" << std::endl;
+  BOOST_CHECK(pairs_in_dimension_0.size() == 2);
+  BOOST_CHECK(pairs_in_dimension_0[0].first == 2);
+  BOOST_CHECK(pairs_in_dimension_0[0].second == std::numeric_limits<Mini_simplex_tree::Filtration_value>::infinity());
+  BOOST_CHECK(pairs_in_dimension_0[1].first == 1);
+  BOOST_CHECK(pairs_in_dimension_0[1].second == std::numeric_limits<Mini_simplex_tree::Filtration_value>::infinity());
+
+  auto pairs_in_dimension_1 = pcoh.pairs_in_dimension(1);
+  std::cout << "pairs_in_dimension_1.size() = " << pairs_in_dimension_1.size() << std::endl;
+  for (int i = 0; i < pairs_in_dimension_1.size(); i++)
+    std::cout << "pairs_in_dimension_1[" << i << "] = [" << pairs_in_dimension_1[i].first << "," <<
+                 pairs_in_dimension_1[i].second << "]" << std::endl;
+  BOOST_CHECK(pairs_in_dimension_1.size() == 1);
+  BOOST_CHECK(pairs_in_dimension_1[0].first == 4);
+  BOOST_CHECK(pairs_in_dimension_1[0].second == std::numeric_limits<Mini_simplex_tree::Filtration_value>::infinity());
+
+  auto pairs_in_dimension_2 = pcoh.pairs_in_dimension(2);
+  std::cout << "pairs_in_dimension_2.size() = " << pairs_in_dimension_2.size() << std::endl;
+  BOOST_CHECK(pairs_in_dimension_2.size() == 0);
 }