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MetisIndex-inl.h
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/* ----------------------------------------------------------------------------
* GTSAM Copyright 2010, Georgia Tech Research Corporation,
* Atlanta, Georgia 30332-0415
* All Rights Reserved
* Authors: Frank Dellaert, et al. (see THANKS for the full author list)
* See LICENSE for the license information
* -------------------------------------------------------------------------- */
#pragma once
#include <map>
#include <vector>
namespace gtsam {
/* ************************************************************************* */
template<class FACTORGRAPH>
void MetisIndex::augment(const FACTORGRAPH& factors) {
std::map<int32_t, std::set<int32_t> > iAdjMap; // Stores a set of keys that are adjacent to key x, with adjMap.first
std::map<int32_t, std::set<int32_t> >::iterator iAdjMapIt;
std::set<Key> keySet;
/* ********** Convert to CSR format ********** */
// Assuming that vertex numbering starts from 0 (C style),
// then the adjacency list of vertex i is stored in array adjncy
// starting at index xadj[i] and ending at(but not including)
// index xadj[i + 1](i.e., adjncy[xadj[i]] through
// and including adjncy[xadj[i + 1] - 1]).
int32_t keyCounter = 0;
// First: Record a copy of each key inside the factorgraph and create a
// key to integer mapping. This is referenced during the adjaceny step
for (size_t i = 0; i < factors.size(); i++) {
if (factors[i]) {
for(const Key& key: *factors[i]) {
keySet.insert(keySet.end(), key); // Keep a track of all unique keys
if (intKeyBMap_.left.find(key) == intKeyBMap_.left.end()) {
intKeyBMap_.insert(bm_type::value_type(key, keyCounter));
keyCounter++;
}
}
}
}
// Create an adjacency mapping that stores the set of all adjacent keys for every key
for (size_t i = 0; i < factors.size(); i++) {
if (factors[i]) {
for(const Key& k1: *factors[i])
for(const Key& k2: *factors[i])
if (k1 != k2) {
// Store both in Key and int32_t format
int i = intKeyBMap_.left.at(k1);
int j = intKeyBMap_.left.at(k2);
iAdjMap[i].insert(iAdjMap[i].end(), j);
}
}
}
// Number of keys referenced in this factor graph
nKeys_ = keySet.size();
xadj_.push_back(0); // Always set the first index to zero
for (iAdjMapIt = iAdjMap.begin(); iAdjMapIt != iAdjMap.end(); ++iAdjMapIt) {
std::vector<int32_t> temp;
// Copy from the FastSet into a temporary vector
std::copy(iAdjMapIt->second.begin(), iAdjMapIt->second.end(),
std::back_inserter(temp));
// Insert each index's set in order by appending them to the end of adj_
adj_.insert(adj_.end(), temp.begin(), temp.end());
//adj_.push_back(temp);
xadj_.push_back((int32_t) adj_.size());
}
}
} // \ gtsam
gtsam
Global functions in a separate testing namespace.
Definition chartTesting.h:28
gtsam::Key
std::uint64_t Key
Integer nonlinear key type.
Definition types.h:100
gtsam::MetisIndex::augment
void augment(const FACTORGRAPH &factors)
Augment the variable index with new factors.
Definition MetisIndex-inl.h:27