void Ioss::Map::build_reverse_map(int64_t num_to_get, int64_t offset)
{
// Stored as a sorted vector of <global_id, local_id> pairs...
// To build incrementally:
// 0. PRE: reverseElementMap is sorted, size >= 0.
// 1. Build vector of current ids. -- new_ids
// 2. Sort that vector.
// 3. Copy reverseElementMap to old_ids, empty reverseElementMap.
// 4. Merge old_ids and new_ids to reverseElementMap.
// 5. Check for duplicate global_ids...
// Build a vector containing the current ids...
ReverseMapContainer new_ids(num_to_get);
for (int64_t i=0; i < num_to_get; i++) {
int64_t local_id = offset + i + 1;
new_ids[i] = std::make_pair(map[local_id], local_id);
if (map[local_id] <= 0) {
std::ostringstream errmsg;
errmsg << "\nERROR: " << entityType << " map detected non-positive global id " << map[local_id]
<< " for " << entityType << " with local id " << local_id
<< " on processor " << myProcessor << ".\n";
IOSS_ERROR(errmsg);
}
}
// Sort that vector...
std::sort(new_ids.begin(), new_ids.end(), IdPairCompare());
int64_t new_id_min = new_ids.empty() ? 0 : new_ids.front().first;
int64_t old_id_max = reverse.empty() ? 0 : reverse.back().first;
if (new_id_min > old_id_max) {
reverse.insert(reverse.end(), new_ids.begin(), new_ids.end());
} else {
// Copy reverseElementMap to old_ids, empty reverseElementMap.
ReverseMapContainer old_ids;
old_ids.swap(reverse);
assert(reverse.empty());
// Merge old_ids and new_ids to reverseElementMap.
reverse.reserve(old_ids.size() + new_ids.size());
std::merge(old_ids.begin(), old_ids.end(),
new_ids.begin(), new_ids.end(),
std::inserter(reverse, reverse.begin()), IdPairCompare());
}
// Check for duplicate ids...
#ifndef NDEBUG
verify_no_duplicate_ids(reverse);
#endif
}
int64_t Ioss::Map::global_to_local(int64_t global, bool must_exist) const
{
int64_t local = global;
if (map[0] == 1) {
RMapI iter = std::lower_bound(reverse.begin(), reverse.end(), global, IdPairCompare());
if (iter != reverse.end() && iter->first == global)
local = iter->second;
else
local = 0;
} else if (!must_exist && global > (int64_t)map.size()-1) {
local = 0;
}
if (local > (int64_t)map.size()-1 || (local <= 0 && must_exist)) {
std::ostringstream errmsg;
errmsg << "ERROR: Ioss Mapping routines detected " << entityType << " with global id equal to " << global
<< " returns a local id of " << local
<< " which is invalid. This should not happen, please report.\n";
IOSS_ERROR(errmsg);
}
return local;
}