70 lines
2.0 KiB
C++
70 lines
2.0 KiB
C++
/* ----------------------------------------------------------------------------
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* GTSAM Copyright 2010, Georgia Tech Research Corporation,
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* Atlanta, Georgia 30332-0415
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* All Rights Reserved
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* Authors: Frank Dellaert, et al. (see THANKS for the full author list)
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* See LICENSE for the license information
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* -------------------------------------------------------------------------- */
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/*
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* DSFVector.cpp
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*
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* Created on: Jun 25, 2010
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* Author: nikai
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* Description: a faster implementation for DSF, which uses vector rather than btree.
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* As a result, the size of the forest is prefixed.
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*/
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#include <gtsam/base/DSFVector.h>
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using namespace std;
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namespace gtsam {
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/* ************************************************************************* */
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DSFVector::DSFVector (const size_t numNodes) {
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resize(numNodes);
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int index = 0;
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for(iterator it = begin(); it!=end(); it++, index++)
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*it = index;
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}
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/* ************************************************************************* */
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size_t DSFVector::findSet(const size_t& key) const {
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size_t parent = at(key);
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return parent == key ? key : findSet(parent);
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}
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/* ************************************************************************* */
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std::set<size_t> DSFVector::set(const std::size_t& label) const {
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std::set<size_t> set;
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size_t key = 0;
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std::vector<std::size_t>::const_iterator it = begin();
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for (; it != end(); it++, key++) {
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if (*it == label || findSet(*it) == label)
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set.insert(key);
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}
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return set;
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}
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/* ************************************************************************* */
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void DSFVector::makeUnionInPlace(const std::size_t& i1, const std::size_t& i2) {
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at(findSet(i2)) = findSet(i1);
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}
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/* ************************************************************************* */
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std::map<size_t, std::set<size_t> > DSFVector::sets() const {
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std::map<size_t, std::set<size_t> > sets;
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size_t key = 0;
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std::vector<std::size_t>::const_iterator it = begin();
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for (; it != end(); it++, key++) {
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sets[findSet(*it)].insert(key);
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}
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return sets;
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}
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}
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