This abstract class serves as a base class for all implementations of track processors. More...

#include <QuadTreeProcessor.h>

Public Types
using	Item = QuadTreeItem< AData >
	The QuadTree will only see items of this type.

using	QuadTree = QuadTreeNode< AX, AY, Item >
	The used QuadTree.

using	XSpan = typename QuadTree::XSpan
	This pair describes the span in X for a node.

using	YSpan = typename QuadTree::YSpan
	This pair describes the span in Y for a node.

using	XYSpans = std::pair< XSpan, YSpan >
	This pair of spans describes the span of a node.

using	QuadTreeChildren = typename QuadTree::Children
	Alias for the QuadTree Children.

using	CandidateReceiver = std::function< void(const std::vector< AData * > &, QuadTree *)>
	This lambda function can be used for postprocessing.

Public Member Functions
	QuadTreeProcessor (int lastLevel, int seedLevel, const XYSpans &xySpans, bool debugOutput=false)
	Constructor is very simple.

virtual	~QuadTreeProcessor ()
	Destructor deletes the quad tree.

void	clear ()
	Delete all the QuadTreeItems in the tree and clear the tree.

void	seed (const std::vector< AData * > &datas)
	Fill in the items in the given vector.

std::vector< AData * >	getAssignedItems ()
	Get items that have been assigned to the seed level The returned elements are unique even if items are assigned multiple times.

void	fill (const CandidateReceiver &candidateReceiver, int nHitsThreshold)
	Start filling the already created tree.

void	fill (const CandidateReceiver &candidateReceiver, int nHitsThreshold, float yLimit)
	Fill vector of QuadTree instances with hits.

virtual void	afterFillDebugHook (QuadTreeChildren &children)
	Override that function if you want to receive debug output whenever the children of a node are filled the first time Maybe you want to make some nice plots or statistics.

const std::map< std::pair< AX, AY >, std::vector< Item * > > &	getDebugInformation () const
	Return the debug information if collected.

Protected Member Functions
virtual XYSpans	createChild (QuadTree *node, int iX, int iY) const
	Implement that function if you want to provide a new processor.

virtual bool	isInNode (QuadTree node, AData item) const =0
	Implement that function if you want to provide a new processor.

virtual bool	isLeaf (QuadTree *node) const
	Function which checks if given node is leaf Implemented as virtual to keep possibility of changing lastLevel values depending on region is phase-space (i.e.

int	getLastLevel () const
	Return the parameter last level.

Protected Attributes
std::unique_ptr< QuadTree >	m_quadTree
	The quad tree we work with.

std::deque< Item >	m_items
	Storage space for the items that are referenced by the quad tree nodes.

std::vector< QuadTree * >	m_seededTrees
	Vector of QuadTrees QuadTree instances (which are filled in the vector) cover the whole Legendre phase-space; each instance is processes independently.

Private Member Functions
void	fillGivenTree (QuadTree *node, const CandidateReceiver &candidateReceiver, int nItemsThreshold, AY yLimit)
	Internal function to do the real quad tree search: fill the nodes, check which of the n*m bins we need to process further and go one level deeper.

void	createChildren (QuadTree *node, QuadTreeChildren &m_children) const
	Creates the sub node of a given node.

void	fillChildren (QuadTree node, const std::vector< Item > &items)
	This function is called by fillGivenTree and fills the items into the corresponding children.

void	callResultFunction (QuadTree *node, const CandidateReceiver &candidateReceiver) const
	When a node is accepted as a result, we extract a vector with the items (back transformed to AData*) and pass it together with the result node to the candidate receiver function.

Private Attributes
int	m_lastLevel
	The last level to be filled.

int	m_seedLevel
	The first level to be filled, effectively skip forward to this higher granularity level.

bool	m_debugOutput
	A flag to control the creation of the debug output.

std::map< std::pair< AX, AY >, std::vector< Item * > >	m_debugOutputMap
	The calculated debug map.

Detailed Description

template<typename AX, typename AY, class AData>
class Belle2::TrackFindingCDC::QuadTreeProcessor< AX, AY, AData >

This abstract class serves as a base class for all implementations of track processors.

It provides some functions to create, fill, clear and postprocess a quad tree. If you want to use your own class as a quad tree item, you have to overload this processor. You have provide only the two functions isInNode and createChild.

Definition at line 37 of file QuadTreeProcessor.h.

Member Typedef Documentation

◆ CandidateReceiver

using CandidateReceiver = std::function<void(const std::vector<AData*>&, QuadTree*)>

This lambda function can be used for postprocessing.

Definition at line 59 of file QuadTreeProcessor.h.

◆ Item

using Item = QuadTreeItem<AData>

The QuadTree will only see items of this type.

Definition at line 41 of file QuadTreeProcessor.h.

◆ QuadTree

using QuadTree = QuadTreeNode<AX, AY, Item>

The used QuadTree.

Definition at line 44 of file QuadTreeProcessor.h.

◆ QuadTreeChildren

using QuadTreeChildren = typename QuadTree::Children

Alias for the QuadTree Children.

Definition at line 56 of file QuadTreeProcessor.h.

◆ XSpan

using XSpan = typename QuadTree::XSpan

This pair describes the span in X for a node.

Definition at line 47 of file QuadTreeProcessor.h.

◆ XYSpans

using XYSpans = std::pair<XSpan, YSpan>

This pair of spans describes the span of a node.

Definition at line 53 of file QuadTreeProcessor.h.

◆ YSpan

using YSpan = typename QuadTree::YSpan

This pair describes the span in Y for a node.

Definition at line 50 of file QuadTreeProcessor.h.

Constructor & Destructor Documentation

◆ QuadTreeProcessor()

QuadTreeProcessor	(	int	lastLevel,
		int	seedLevel,
		const XYSpans &	xySpans,
		bool	debugOutput = `false`
	)

inline

Constructor is very simple.

The QuadTree has to be constructed elsewhere.

Parameters

lastLevel	describing the last search level for the quad tree creation
seedLevel	first level to be filled, effectively skip forward to this higher granularity level
xySpans	pair of spans describing the span of a node
debugOutput	enable debug output

Definition at line 69 of file QuadTreeProcessor.h.

        : m_quadTree{std::make_unique<QuadTree>(xySpans.first, xySpans.second, 0, nullptr)}
        , m_lastLevel(lastLevel)
        , m_seedLevel(seedLevel)
        , m_debugOutput(debugOutput)
        , m_debugOutputMap()
      {
      }

◆ ~QuadTreeProcessor()

virtual ~QuadTreeProcessor ( )

inlinevirtual

Destructor deletes the quad tree.

Definition at line 84 of file QuadTreeProcessor.h.

      {
        clear();
      }

Member Function Documentation

◆ afterFillDebugHook()

virtual void afterFillDebugHook ( QuadTreeChildren & children )

inlinevirtual

Override that function if you want to receive debug output whenever the children of a node are filled the first time Maybe you want to make some nice plots or statistics.

Definition at line 356 of file QuadTreeProcessor.h.

      {
        if (not m_debugOutput) return;
        for (QuadTree& childNode : children) {
          if (childNode.getLevel() != getLastLevel()) continue; // Only write the lowest level
          //m_debugOutputMap[ {childNode.getXMean(), childNode.getYMean()}] = childNode.getItems();
        }
      }

◆ callResultFunction()

void callResultFunction	(	QuadTree *	node,
		const CandidateReceiver &	candidateReceiver
	)		const

inlineprivate

When a node is accepted as a result, we extract a vector with the items (back transformed to AData*) and pass it together with the result node to the candidate receiver function.

Definition at line 288 of file QuadTreeProcessor.h.

      {
        const std::vector<Item*>& foundItems = node->getItems();
        std::vector<AData*> candidate;
        candidate.reserve(foundItems.size());
 
        for (Item* item : foundItems) {
          item->setUsedFlag();
          candidate.push_back(item->getPointer());
        }
 
        candidateReceiver(candidate, node);
      }

◆ clear()

void clear ( )

inline

Delete all the QuadTreeItems in the tree and clear the tree.

Definition at line 92 of file QuadTreeProcessor.h.

      {
        m_seededTrees.clear();
        m_quadTree->clearChildren();
        m_quadTree->clearItems();
        m_items.clear();
      }

◆ createChild()

virtual XYSpans createChild	(	QuadTree *	node,
		int	iX,
		int	iY
	)		const

inlineprotectedvirtual

Implement that function if you want to provide a new processor.

It decides which node-spans the n * m children of the node should have. It is called when creating the nodes. The two indices iX and iY tell you where the new node will be created (as node.children[iX][iY]). You can check some information on the level or the x- or y-values by using the methods implemented for node.

Returns: a XYSpan pair of a x- and a y-span that the new child should have. If you don nt want to provide custom spans, just return XYSpans(XSpan(node->getXBinBound(iX), node->getXBinBound(iX + 1)), YSpan(node->getYBinBound(iY), node->getYBinBound(iY + 1)));

Definition at line 311 of file QuadTreeProcessor.h.

      {
        AX xMin = node->getXLowerBound(iX);
        AX xMax = node->getXUpperBound(iX);
        AY yMin = node->getYLowerBound(iY);
        AY yMax = node->getYUpperBound(iY);
        return XYSpans({xMin, xMax}, {yMin, yMax});
      }

◆ createChildren()

void createChildren	(	QuadTree *	node,
		QuadTreeChildren &	m_children
	)		const

inlineprivate

Creates the sub node of a given node.

This function is called by fillGivenTree. To calculate the spans of the children nodes the user-defined function createChiildWithParent is used.

Definition at line 249 of file QuadTreeProcessor.h.

      {
        for (int i = 0; i < node->getXNbins(); ++i) {
          for (int j = 0; j < node->getYNbins(); ++j) {
            const XYSpans& xySpans = createChild(node, i, j);
            const XSpan& xSpan = xySpans.first;
            const YSpan& ySpan = xySpans.second;
            m_children.push_back(QuadTree(xSpan, ySpan, node->getLevel() + 1, node));
          }
        }
      }

◆ fill() [1/2]

void fill	(	const CandidateReceiver &	candidateReceiver,
		int	nHitsThreshold
	)

inline

Start filling the already created tree.

Parameters

candidateReceiver	the lambda function to call after a node was selected
nHitsThreshold	the threshold on the number of items

Definition at line 168 of file QuadTreeProcessor.h.

      {
        fill(candidateReceiver, nHitsThreshold, std::numeric_limits<AY>::max());
      }

◆ fill() [2/2]

void fill	(	const CandidateReceiver &	candidateReceiver,
		int	nHitsThreshold,
		float	yLimit
	)

inline

Fill vector of QuadTree instances with hits.

Parameters

candidateReceiver	the lambda function to call after a node was selected
nHitsThreshold	the threshold on the number of items
yLimit	the threshold in the rho (curvature) variable

Definition at line 179 of file QuadTreeProcessor.h.

      {
        std::vector<QuadTree*> quadTrees = m_seededTrees;
        std::sort(quadTrees.begin(), quadTrees.end(), [](QuadTree * quadTree1, QuadTree * quadTree2) {
          return quadTree1->getNItems() > quadTree2->getNItems();
        });
 
        for (QuadTree* tree : quadTrees) {
          erase_remove_if(tree->getItems(), [](Item * hit) { return hit->isUsed(); });
          fillGivenTree(tree, candidateReceiver, nHitsThreshold, yLimit);
        }
      }

◆ fillChildren()

void fillChildren	(	QuadTree *	node,
		const std::vector< Item * > &	items
	)

inlineprivate

This function is called by fillGivenTree and fills the items into the corresponding children.

For this the user-defined method isInNode is called.

Definition at line 265 of file QuadTreeProcessor.h.

      {
        const size_t neededSize = 2 * items.size();
        for (QuadTree& child : node->getChildren()) {
          child.reserveItems(neededSize);
        }
 
        for (Item* item : items) {
          if (item->isUsed()) continue;
 
          for (QuadTree& child : node->getChildren()) {
            if (isInNode(&child, item->getPointer())) {
              child.insertItem(item);
            }
          }
        }
        afterFillDebugHook(node->getChildren());
      }

◆ fillGivenTree()

void fillGivenTree	(	QuadTree *	node,
		const CandidateReceiver &	candidateReceiver,
		int	nItemsThreshold,
		AY	yLimit
	)

inlineprivate

Internal function to do the real quad tree search: fill the nodes, check which of the n*m bins we need to process further and go one level deeper.

Definition at line 197 of file QuadTreeProcessor.h.

      {
        if (node->getNItems() < nItemsThreshold) {
          return;
        }
 
        if ((node->getYMin() > yLimit) or (-node->getYMax() > yLimit)) {
          return;
        }
 
        if (isLeaf(node)) {
          callResultFunction(node, candidateReceiver);
          return;
        }
 
        if (node->getChildren().empty()) {
          this->createChildren(node, node->getChildren());
        }
 
        if (!node->checkFilled()) {
          fillChildren(node, node->getItems());
          node->setFilled();
        }
 
        std::vector<QuadTree*> children;
        for (QuadTree& child : node->getChildren()) {
          children.push_back(&child);
        }
        const auto compareNItems = [](const QuadTree * lhs, const QuadTree * rhs) {
          return lhs->getNItems() < rhs->getNItems();
        };
 
        // Explicitly count down the children
        const int nChildren = children.size();
        for (int iChild = 0; iChild < nChildren; ++iChild) {
          auto itHeaviestChild = std::max_element(children.begin(), children.end(), compareNItems);
          QuadTree* heaviestChild = *itHeaviestChild;
          children.erase(itHeaviestChild);
          // After we have processed some children we need to get rid of the already used hits in all the children,
          // because this can change the number of items drastically
          erase_remove_if(heaviestChild->getItems(), [&](Item * hit) { return hit->isUsed(); });
          this->fillGivenTree(heaviestChild, candidateReceiver, nItemsThreshold, yLimit);
        }
      }

◆ getAssignedItems()

std::vector< AData * > getAssignedItems ( )

inline

Get items that have been assigned to the seed level The returned elements are unique even if items are assigned multiple times.

Definition at line 149 of file QuadTreeProcessor.h.

      {
        std::vector<const CDCWireHit*> result;
        for (QuadTree* seededTree : m_seededTrees) {
          for (Item* item : seededTree->getItems()) {
            result.push_back(item->getPointer());
          }
        }
        std::sort(result.begin(), result.end());
        result.erase(std::unique(result.begin(), result.end()), result.end());
        return result;
      }

◆ getDebugInformation()

const std::map< std::pair< AX, AY >, std::vector< Item * > > & getDebugInformation ( ) const

inline

Return the debug information if collected.

Definition at line 368 of file QuadTreeProcessor.h.

      {
        return m_debugOutputMap;
      }

◆ getLastLevel()

int getLastLevel ( ) const

inlineprotected

Return the parameter last level.

Definition at line 346 of file QuadTreeProcessor.h.

      {
        return m_lastLevel;
      }

◆ isInNode()

virtual bool isInNode	(	QuadTree *	node,
		AData *	item
	)		const

protectedpure virtual

Implement that function if you want to provide a new processor.

It is called when filling the quad tree after creation. For every item in a node and every child node this function gets called and should decide, if the item should go into this child node or not.

Parameters

node	child node
item	item to be filled into the child node or not

Returns: true if this item belongs into this node.

◆ isLeaf()

virtual bool isLeaf ( QuadTree * node ) const

inlineprotectedvirtual

Function which checks if given node is leaf Implemented as virtual to keep possibility of changing lastLevel values depending on region is phase-space (i.e.

setting lastLevel as a function of Y-variable)

Definition at line 334 of file QuadTreeProcessor.h.

      {
        if (node->getLevel() >= m_lastLevel) {
          return true;
        } else {
          return false;
        }
      }

◆ seed()

void seed ( const std::vector< AData * > & datas )

inline

Fill in the items in the given vector.

They are transformed to QuadTreeItems internally.

Definition at line 103 of file QuadTreeProcessor.h.

      {
        // Create the items
        for (AData* data : datas) {
          m_items.emplace_back(data);
        }
 
        // Creating the seed level
        long nSeedBins = pow(2, m_seedLevel);
        m_seededTrees.reserve(nSeedBins * nSeedBins);
 
        // Expand the first levels to the seed sectors
        m_seededTrees.push_back(m_quadTree.get());
        std::vector<QuadTree*> nextSeededTrees;
 
        for (int level = 0; level < m_seedLevel; ++level) {
          for (QuadTree* node : m_seededTrees) {
            if (node->getChildren().empty()) {
              this->createChildren(node, node->getChildren());
            }
            for (QuadTree& child :  node->getChildren()) {
              nextSeededTrees.push_back(&child);
            }
          }
          std::swap(nextSeededTrees, m_seededTrees);
          nextSeededTrees.clear();
        }
 
        // Fill the seed level with the items
        for (QuadTree* seededTree : m_seededTrees) {
          seededTree->reserveItems(m_items.size());
 
          for (Item& item : m_items) {
            if (item.isUsed()) continue;
            if (isInNode(seededTree, item.getPointer())) {
              seededTree->insertItem(&item);
            }
          }
        }
      }

Member Data Documentation

◆ m_debugOutput

bool m_debugOutput

private

A flag to control the creation of the debug output.

Definition at line 395 of file QuadTreeProcessor.h.

◆ m_debugOutputMap

std::map<std::pair<AX, AY>, std::vector<Item*> > m_debugOutputMap

private

The calculated debug map.

Definition at line 398 of file QuadTreeProcessor.h.

◆ m_items

std::deque<Item> m_items

protected

Storage space for the items that are referenced by the quad tree nodes.

Definition at line 378 of file QuadTreeProcessor.h.

◆ m_lastLevel

int m_lastLevel

private

The last level to be filled.

Definition at line 389 of file QuadTreeProcessor.h.

◆ m_quadTree

std::unique_ptr<QuadTree> m_quadTree

protected

The quad tree we work with.

Definition at line 375 of file QuadTreeProcessor.h.

◆ m_seededTrees

std::vector<QuadTree*> m_seededTrees

protected

Vector of QuadTrees QuadTree instances (which are filled in the vector) cover the whole Legendre phase-space; each instance is processes independently.

Definition at line 385 of file QuadTreeProcessor.h.

◆ m_seedLevel

int m_seedLevel

private

The first level to be filled, effectively skip forward to this higher granularity level.

Definition at line 392 of file QuadTreeProcessor.h.

The documentation for this class was generated from the following file:

tracking/trackFindingCDC/legendre/quadtree/include/QuadTreeProcessor.h

Public Types

Public Member Functions

Protected Member Functions

Protected Attributes

Private Member Functions

Private Attributes

Detailed Description

Member Typedef Documentation

◆ CandidateReceiver

◆ Item

◆ QuadTree

◆ QuadTreeChildren

◆ XSpan

◆ XYSpans

◆ YSpan

Constructor & Destructor Documentation

◆ QuadTreeProcessor()

◆ ~QuadTreeProcessor()

Member Function Documentation

◆ afterFillDebugHook()

◆ callResultFunction()

◆ clear()

◆ createChild()

◆ createChildren()

◆ fill() [1/2]

◆ fill() [2/2]

◆ fillChildren()

◆ fillGivenTree()

◆ getAssignedItems()

◆ getDebugInformation()

◆ getLastLevel()

◆ isInNode()

◆ isLeaf()

◆ seed()

Member Data Documentation

◆ m_debugOutput

◆ m_debugOutputMap

◆ m_items

◆ m_lastLevel

◆ m_quadTree

◆ m_seededTrees

◆ m_seedLevel