replace static_cast(-1) by get_null_value in persistence matrix

src/Persistence_matrix/include/gudhi/Matrix.h

@@ -162,7 +162,16 @@ class Matrix {
    */
   using Element = typename Field_operators::Element;
   using Characteristic = typename Field_operators::Characteristic;
-
+
+  /**
+   * @private
+   * @brief Returns value from a type when not set.
+   */
+  template <typename T>
+  static constexpr const T get_null_value() {
+    return -1;
+  }
+
   /**
    * @brief Type for a bar in the computed barcode. Stores the birth, death and dimension of the bar.
    */
@@ -367,7 +376,7 @@ class Matrix {
     //purposely triggers operators() instead of operators(characteristic) as the "dummy" values for the different
     //operators can be different from -1.
     Column_zp_settings(Characteristic characteristic) : operators(), entryConstructor() {
-      if (characteristic != static_cast<Characteristic>(-1)) operators.set_characteristic(characteristic);
+      if (characteristic != get_null_value<Characteristic>()) operators.set_characteristic(characteristic);
     }
     Column_zp_settings(const Column_zp_settings& toCopy)
         : operators(toCopy.operators.get_characteristic()), entryConstructor() {}
@@ -592,7 +601,7 @@ class Matrix {
    * @ref set_characteristic before calling for the first time a method needing it. Ignored if
    * @ref PersistenceMatrixOptions::is_z2 is true.
    */
-  Matrix(unsigned int numberOfColumns, Characteristic characteristic = static_cast<Characteristic>(-1));
+  Matrix(unsigned int numberOfColumns, Characteristic characteristic = get_null_value<Characteristic>());
   /**
    * @brief Constructs a new empty matrix with the given comparator functions. Only available when those comparators
    * are necessary.
@@ -671,7 +680,7 @@ class Matrix {
   Matrix(unsigned int numberOfColumns, 
          const std::function<bool(Pos_index,Pos_index)>& birthComparator,
          const std::function<bool(Pos_index,Pos_index)>& deathComparator, 
-         Characteristic characteristic = static_cast<Characteristic>(-1));
+         Characteristic characteristic = get_null_value<Characteristic>());
   /**
    * @brief Copy constructor.
    * 
@@ -1510,7 +1519,7 @@ template <class PersistenceMatrixOptions>
 inline void Matrix<PersistenceMatrixOptions>::set_characteristic(Characteristic characteristic) 
 {
   if constexpr (!PersistenceMatrixOptions::is_z2) {
-    if (colSettings_->operators.get_characteristic() != static_cast<Characteristic>(-1)) {
+    if (colSettings_->operators.get_characteristic() != get_null_value<Characteristic>()) {
       std::cerr << "Warning: Characteristic already initialised. Changing it could lead to incoherences in the matrix "
                    "as the modulo was already applied to values in existing columns.";
     }
@@ -1524,7 +1533,7 @@ template <class Container>
 inline void Matrix<PersistenceMatrixOptions>::insert_column(const Container& column) 
 {
   if constexpr (!PersistenceMatrixOptions::is_z2){
-    GUDHI_CHECK(colSettings_->operators.get_characteristic() != static_cast<Characteristic>(-1),
+    GUDHI_CHECK(colSettings_->operators.get_characteristic() != get_null_value<Characteristic>(),
                 std::logic_error("Matrix::insert_column - Columns cannot be initialized if the coefficient field "
                                  "characteristic is not specified."));
   }
@@ -1540,7 +1549,7 @@ template <class Container>
 inline void Matrix<PersistenceMatrixOptions>::insert_column(const Container& column, Index columnIndex) 
 {
   if constexpr (!PersistenceMatrixOptions::is_z2){
-    GUDHI_CHECK(colSettings_->operators.get_characteristic() != static_cast<Characteristic>(-1),
+    GUDHI_CHECK(colSettings_->operators.get_characteristic() != get_null_value<Characteristic>(),
                 std::logic_error("Matrix::insert_column - Columns cannot be initialized if the coefficient field "
                                  "characteristic is not specified."));
   }
@@ -1558,7 +1567,7 @@ inline typename Matrix<PersistenceMatrixOptions>::Insertion_return
 Matrix<PersistenceMatrixOptions>::insert_boundary(const Boundary_range& boundary, Dimension dim)
 {
   if constexpr (!PersistenceMatrixOptions::is_z2){
-    GUDHI_CHECK(colSettings_->operators.get_characteristic() != static_cast<Characteristic>(-1),
+    GUDHI_CHECK(colSettings_->operators.get_characteristic() != get_null_value<Characteristic>(),
                 std::logic_error("Matrix::insert_boundary - Columns cannot be initialized if the coefficient field "
                                  "characteristic is not specified."));
   }
@@ -1578,7 +1587,7 @@ Matrix<PersistenceMatrixOptions>::insert_boundary(ID_index cellIndex,
                                                   Dimension dim)
 {
   if constexpr (!PersistenceMatrixOptions::is_z2){
-    GUDHI_CHECK(colSettings_->operators.get_characteristic() != static_cast<Characteristic>(-1),
+    GUDHI_CHECK(colSettings_->operators.get_characteristic() != get_null_value<Characteristic>(),
                 std::logic_error("Matrix::insert_boundary - Columns cannot be initialized if the coefficient field "
                                  "characteristic is not specified."));
   }

src/Persistence_matrix/include/gudhi/Persistence_matrix/Boundary_matrix.h

@@ -558,7 +558,7 @@ inline typename Boundary_matrix<Master_matrix>::Index Boundary_matrix<Master_mat
     pivot = it->second.get_pivot();
     if constexpr (activeSwapOption) {
       // if the removed column is positive, the pivot won't change value
-      if (Swap_opt::rowSwapped_ && pivot != static_cast<ID_index>(-1)) {
+      if (Swap_opt::rowSwapped_ && pivot != Master_matrix::template get_null_value<ID_index>()) {
         Swap_opt::_orderRows();
         pivot = it->second.get_pivot();
       }
@@ -568,7 +568,7 @@ inline typename Boundary_matrix<Master_matrix>::Index Boundary_matrix<Master_mat
     pivot = matrix_[nextInsertIndex_].get_pivot();
     if constexpr (activeSwapOption) {
       // if the removed column is positive, the pivot won't change value
-      if (Swap_opt::rowSwapped_ && pivot != static_cast<ID_index>(-1)) {
+      if (Swap_opt::rowSwapped_ && pivot != Master_matrix::template get_null_value<ID_index>()) {
         Swap_opt::_orderRows();
         pivot = matrix_[nextInsertIndex_].get_pivot();
       }

src/Persistence_matrix/include/gudhi/Persistence_matrix/Chain_matrix.h

@@ -700,7 +700,9 @@ inline std::vector<typename Master_matrix::Entry_representative> Chain_matrix<Ma
   }
 
   if constexpr (Master_matrix::Option_list::has_matrix_maximal_dimension_access) {
-    Dim_opt::update_up(dim == static_cast<Dimension>(-1) ? (boundary.size() == 0 ? 0 : boundary.size() - 1) : dim);
+    Dim_opt::update_up(dim == Master_matrix::template get_null_value<Dimension>()
+                           ? (boundary.size() == 0 ? 0 : boundary.size() - 1)
+                           : dim);
   }
 
   return _reduce_boundary(cellID, boundary, dim);
@@ -915,7 +917,7 @@ inline void Chain_matrix<Master_matrix>::print() const
   if constexpr (!Master_matrix::Option_list::has_map_column_container) {
     for (ID_index i = 0; i < pivotToColumnIndex_.size(); ++i) {
       Index pos = pivotToColumnIndex_[i];
-      if (pos != static_cast<Index>(-1)){
+      if (pos != Master_matrix::template get_null_value<Index>()){
         const Column& col = matrix_[pos];
         for (const auto& entry : col) {
           std::cout << entry.get_row_index() << " ";
@@ -928,7 +930,7 @@ inline void Chain_matrix<Master_matrix>::print() const
       std::cout << "Row Matrix:\n";
       for (ID_index i = 0; i < pivotToColumnIndex_.size(); ++i) {
         Index pos = pivotToColumnIndex_[i];
-        if (pos != static_cast<Index>(-1)){
+        if (pos != Master_matrix::template get_null_value<Index>()){
           const Row& row = RA_opt::get_row(pos);
           for (const auto& entry : row) {
             std::cout << entry.get_column_index() << " ";
@@ -966,7 +968,8 @@ inline std::vector<typename Master_matrix::Entry_representative> Chain_matrix<Ma
     ID_index cellID, const Boundary_range& boundary, Dimension dim)
 {
   Tmp_column column(boundary.begin(), boundary.end());
-  if (dim == static_cast<Dimension>(-1)) dim = boundary.begin() == boundary.end() ? 0 : boundary.size() - 1;
+  if (dim == Master_matrix::template get_null_value<Dimension>())
+    dim = boundary.begin() == boundary.end() ? 0 : boundary.size() - 1;
   std::vector<Entry_representative> chainsInH;  // for corresponding indices in H (paired columns)
   std::vector<Entry_representative> chainsInF;  // for corresponding indices in F (unpaired, essential columns)
 
@@ -1225,7 +1228,7 @@ inline void Chain_matrix<Master_matrix>::_remove_last(Index lastIndex)
     auto it = _indexToBar().find(--_nextPosition());
     typename Barcode::iterator bar = it->second;
 
-    if (bar->death == static_cast<Pos_index>(-1))
+    if (bar->death == Master_matrix::template get_null_value<Pos_index>())
       _barcode().erase(bar);
     else
       bar->death = -1;

src/Persistence_matrix/include/gudhi/Persistence_matrix/Id_to_index_overlay.h

@@ -760,8 +760,9 @@ inline void Id_to_index_overlay<Underlying_matrix, Master_matrix>::insert_bounda
     GUDHI_CHECK(idToIndex_->find(cellIndex) == idToIndex_->end(),
                 std::invalid_argument("Id_to_index_overlay::insert_boundary - Index for simplex already chosen!"));
   } else {
-    GUDHI_CHECK((idToIndex_->size() <= cellIndex || _id_to_index(cellIndex) == static_cast<Index>(-1)),
-                std::invalid_argument("Id_to_index_overlay::insert_boundary - Index for simplex already chosen!"));
+    GUDHI_CHECK(
+        (idToIndex_->size() <= cellIndex || _id_to_index(cellIndex) == Master_matrix::template get_null_value<Index>()),
+        std::invalid_argument("Id_to_index_overlay::insert_boundary - Index for simplex already chosen!"));
   }
   matrix_.insert_boundary(cellIndex, boundary, dim);
   if constexpr (Master_matrix::Option_list::is_of_boundary_type) {
@@ -808,7 +809,7 @@ inline void Id_to_index_overlay<Underlying_matrix, Master_matrix>::remove_maxima
       }
     } else {
       for (ID_index i = 0; i < idToIndex_->size(); ++i) {
-        if (_id_to_index(i) != static_cast<Index>(-1)) indexToID[_id_to_index(i)] = i;
+        if (_id_to_index(i) != Master_matrix::template get_null_value<Index>()) indexToID[_id_to_index(i)] = i;
       }
     }
     --nextIndex_;
@@ -857,7 +858,8 @@ inline void Id_to_index_overlay<Underlying_matrix, Master_matrix>::remove_last()
       idToIndex_->erase(it);
     } else {
       Index id = idToIndex_->size() - 1;
-      while (_id_to_index(id) == static_cast<Index>(-1)) --id;  // should always stop before reaching -1
+      // should always stop before reaching -1
+      while (_id_to_index(id) == Master_matrix::template get_null_value<Index>()) --id;
       GUDHI_CHECK(_id_to_index(id) == nextIndex_,
                   std::logic_error("Id_to_index_overlay::remove_last - Indexation problem."));
       _id_to_index(id) = -1;

src/Persistence_matrix/include/gudhi/Persistence_matrix/RU_matrix.h

@@ -604,7 +604,7 @@ inline void RU_matrix<Master_matrix>::remove_last()
     pivotToColumnIndex_.erase(reducedMatrixR_.remove_last());
   } else {
     ID_index lastPivot = reducedMatrixR_.remove_last();
-    if (lastPivot != static_cast<ID_index>(-1)) pivotToColumnIndex_[lastPivot] = -1;
+    if (lastPivot != Master_matrix::template get_null_value<ID_index>()) pivotToColumnIndex_[lastPivot] = -1;
   }
 
   // if has_vine_update and has_column_pairings are both true,
@@ -752,7 +752,7 @@ inline void RU_matrix<Master_matrix>::_insert_boundary(Index currentIndex)
 
   if constexpr (!Master_matrix::Option_list::has_map_column_container) {
     ID_index pivot = reducedMatrixR_.get_column(currentIndex).get_pivot();
-    if (pivot != static_cast<ID_index>(-1) && pivotToColumnIndex_.size() <= pivot)
+    if (pivot != Master_matrix::template get_null_value<ID_index>() && pivotToColumnIndex_.size() <= pivot)
       pivotToColumnIndex_.resize((pivot + 1) * 2, -1);
   }
 
@@ -806,7 +806,7 @@ template <class Master_matrix>
 inline void RU_matrix<Master_matrix>::_reduce_column(Index target, Index eventIndex)
 {
   auto get_column_with_pivot_ = [&](ID_index pivot) -> Index {
-    if (pivot == static_cast<ID_index>(-1)) return -1;
+    if (pivot == Master_matrix::template get_null_value<ID_index>()) return -1;
     if constexpr (Master_matrix::Option_list::has_map_column_container) {
       auto it = pivotToColumnIndex_.find(pivot);
       if (it == pivotToColumnIndex_.end())
@@ -822,13 +822,14 @@ inline void RU_matrix<Master_matrix>::_reduce_column(Index target, Index eventIn
   ID_index pivot = curr.get_pivot();
   Index currIndex = get_column_with_pivot_(pivot);
 
-  while (pivot != static_cast<ID_index>(-1) && currIndex != static_cast<Index>(-1)) {
+  while (pivot != Master_matrix::template get_null_value<ID_index>() &&
+         currIndex != Master_matrix::template get_null_value<Index>()) {
     _reduce_column_by(target, currIndex);
     pivot = curr.get_pivot();
     currIndex = get_column_with_pivot_(pivot);
   }
 
-  if (pivot != static_cast<ID_index>(-1)) {
+  if (pivot != Master_matrix::template get_null_value<ID_index>()) {
     if constexpr (Master_matrix::Option_list::has_map_column_container) {
       pivotToColumnIndex_.try_emplace(pivot, target);
     } else {

src/Persistence_matrix/include/gudhi/Persistence_matrix/base_pairing.h

@@ -155,7 +155,8 @@ inline void Base_pairing<Master_matrix>::_reduce()
         auto itNeg = negativeColumns.find(pivotColumnNumber);
         Index pivotKiller = itNeg == negativeColumns.end() ? -1 : itNeg->second;
 
-        while (pivot != static_cast<ID_index>(-1) && pivotKiller != static_cast<Index>(-1)) {
+        while (pivot != Master_matrix::template get_null_value<ID_index>() &&
+               pivotKiller != Master_matrix::template get_null_value<Index>()) {
           if constexpr (Master_matrix::Option_list::is_z2) {
             curr += _matrix()->get_column(pivotKiller);
           } else {
@@ -174,7 +175,7 @@ inline void Base_pairing<Master_matrix>::_reduce()
           pivotKiller = itNeg == negativeColumns.end() ? -1 : itNeg->second;
         }
 
-        if (pivot != static_cast<ID_index>(-1)) {
+        if (pivot != Master_matrix::template get_null_value<ID_index>()) {
           negativeColumns.emplace(pivotColumnNumber, i);
           _matrix()->get_column(pivotColumnNumber).clear();
           barcode_.emplace_back(pivotColumnNumber, i, dim - 1);
@@ -193,7 +194,7 @@ inline void Base_pairing<Master_matrix>::_reduce()
     // map can only be constructed once barcode is sorted
     for (Index i = 0; i < barcode_.size(); ++i) {
       auto d = barcode_[i].death;
-      if (d != static_cast<Pos_index>(-1)) {
+      if (d != Master_matrix::template get_null_value<Pos_index>()) {
         deathToBar_.emplace(d, i);
       }
     }

src/Persistence_matrix/include/gudhi/Persistence_matrix/columns/chain_column_extra_properties.h

@@ -105,7 +105,7 @@ class Chain_column_extra_properties
    * @return true If the column is paired.
    * @return false Otherwise.
    */
-  bool is_paired() const { return pairedColumn_ != static_cast<Index>(-1); }
+  bool is_paired() const { return pairedColumn_ != Master_matrix::template get_null_value<Index>(); }
   /**
    * @brief Sets the value of the pair.
    * 

src/Persistence_matrix/include/gudhi/Persistence_matrix/columns/heap_column.h

@@ -634,7 +634,7 @@ inline typename Heap_column<Master_matrix>::Field_element Heap_column<Master_mat
       return 0;
     } else {
       Field_element sum(0);
-      if (Chain_opt::get_pivot() == static_cast<ID_index>(-1)) return sum;
+      if (Chain_opt::get_pivot() == Master_matrix::template get_null_value<ID_index>()) return sum;
       for (const Entry* entry : column_) {
         if (entry->get_row_index() == Chain_opt::get_pivot()) operators_->add_inplace(sum, entry->get_element());
       }

src/Persistence_matrix/include/gudhi/Persistence_matrix/columns/intrusive_list_column.h

@@ -510,7 +510,7 @@ inline void Intrusive_list_column<Master_matrix>::reorder(const Row_index_map& v
     Entry* entry = &(*it);
     if constexpr (Master_matrix::Option_list::has_row_access) {
       RA_opt::unlink(entry);
-      if (columnIndex != static_cast<Index>(-1)) entry->set_column_index(columnIndex);
+      if (columnIndex != Master_matrix::template get_null_value<Index>()) entry->set_column_index(columnIndex);
     }
     entry->set_row_index(valueMap.at(entry->get_row_index()));
     if constexpr (Master_matrix::Option_list::has_intrusive_rows && Master_matrix::Option_list::has_row_access)
@@ -576,7 +576,7 @@ Intrusive_list_column<Master_matrix>::get_pivot_value() const
       if (column_.empty()) return 0;
       return column_.back().get_element();
     } else {
-      if (Chain_opt::get_pivot() == static_cast<ID_index>(-1)) return Field_element();
+      if (Chain_opt::get_pivot() == Master_matrix::template get_null_value<ID_index>()) return Field_element();
       for (const Entry& entry : column_) {
         if (entry.get_row_index() == Chain_opt::get_pivot()) return entry.get_element();
       }

src/Persistence_matrix/include/gudhi/Persistence_matrix/columns/intrusive_set_column.h

@@ -499,7 +499,8 @@ inline void Intrusive_set_column<Master_matrix>::reorder(const Row_index_map& va
   if constexpr (Master_matrix::Option_list::has_row_access) {
     for (auto it = column_.begin(); it != column_.end();) {
       Entry* newEntry = entryPool_->construct(
-          columnIndex == static_cast<Index>(-1) ? RA_opt::columnIndex_ : columnIndex, valueMap.at(it->get_row_index()));
+          columnIndex == Master_matrix::template get_null_value<Index>() ? RA_opt::columnIndex_ : columnIndex,
+          valueMap.at(it->get_row_index()));
       if constexpr (!Master_matrix::Option_list::is_z2) {
         newEntry->set_element(it->get_element());
       }
@@ -578,7 +579,7 @@ Intrusive_set_column<Master_matrix>::get_pivot_value() const
       if (column_.empty()) return 0;
       return column_.rbegin()->get_element();
     } else {
-      if (Chain_opt::get_pivot() == static_cast<ID_index>(-1)) return 0;
+      if (Chain_opt::get_pivot() == Master_matrix::template get_null_value<ID_index>()) return 0;
       auto it = column_.find(Entry(Chain_opt::get_pivot()));
       GUDHI_CHECK(it != column_.end(),
                   "Intrusive_set_column::get_pivot_value - Pivot not found only if the column was misused.");

src/Persistence_matrix/include/gudhi/Persistence_matrix/columns/list_column.h

@@ -499,7 +499,7 @@ inline void List_column<Master_matrix>::reorder(const Row_index_map& valueMap, [
     Entry* entry = *it;
     if constexpr (Master_matrix::Option_list::has_row_access) {
       RA_opt::unlink(entry);
-      if (columnIndex != static_cast<Index>(-1)) entry->set_column_index(columnIndex);
+      if (columnIndex != Master_matrix::template get_null_value<Index>()) entry->set_column_index(columnIndex);
     }
     entry->set_row_index(valueMap.at(entry->get_row_index()));
     if constexpr (Master_matrix::Option_list::has_intrusive_rows && Master_matrix::Option_list::has_row_access)
@@ -569,7 +569,7 @@ inline typename List_column<Master_matrix>::Field_element List_column<Master_mat
       if (column_.empty()) return 0;
       return column_.back()->get_element();
     } else {
-      if (Chain_opt::get_pivot() == static_cast<ID_index>(-1)) return Field_element();
+      if (Chain_opt::get_pivot() == Master_matrix::template get_null_value<ID_index>()) return Field_element();
       for (const Entry* entry : column_) {
         if (entry->get_row_index() == Chain_opt::get_pivot()) return entry->get_element();
       }

src/Persistence_matrix/include/gudhi/Persistence_matrix/columns/naive_vector_column.h

@@ -488,7 +488,7 @@ inline void Naive_vector_column<Master_matrix>::reorder(const Row_index_map& val
   for (Entry* entry : column_) {
     if constexpr (Master_matrix::Option_list::has_row_access) {
       RA_opt::unlink(entry);
-      if (columnIndex != static_cast<Index>(-1)) entry->set_column_index(columnIndex);
+      if (columnIndex != Master_matrix::template get_null_value<Index>()) entry->set_column_index(columnIndex);
     }
     entry->set_row_index(valueMap.at(entry->get_row_index()));
     if constexpr (Master_matrix::Option_list::has_intrusive_rows && Master_matrix::Option_list::has_row_access)
@@ -559,7 +559,7 @@ inline typename Naive_vector_column<Master_matrix>::Field_element Naive_vector_c
     if constexpr (Master_matrix::Option_list::is_of_boundary_type) {
       return column_.empty() ? Field_element() : column_.back()->get_element();
     } else {
-      if (Chain_opt::get_pivot() == static_cast<ID_index>(-1)) return Field_element();
+      if (Chain_opt::get_pivot() == Master_matrix::template get_null_value<ID_index>()) return Field_element();
       for (const Entry* entry : column_) {
         if (entry->get_row_index() == Chain_opt::get_pivot()) return entry->get_element();
       }