KinematicTree Class Reference

#include <KinematicTree.h>

Inheritance diagram for KinematicTree:

Public Member Functions
void	addParticle (RefCountedKinematicVertex prodVtx, RefCountedKinematicVertex decVtx, RefCountedKinematicParticle part)
void	addTree (RefCountedKinematicVertex vtx, KinematicTree *tr)
RefCountedKinematicVertex	currentDecayVertex () const
RefCountedKinematicParticle	currentParticle () const
RefCountedKinematicVertex	currentProductionVertex () const
std::vector < RefCountedKinematicParticle >	daughterParticles () const
std::vector < RefCountedKinematicParticle >	finalStateParticles () const
bool	findDecayVertex (const RefCountedKinematicVertex vert) const
bool	findDecayVertex (KinematicVertex *vert) const
bool	findParticle (const RefCountedKinematicParticle part) const
bool	isConsistent () const
bool	isEmpty () const
bool	isValid () const
	KinematicTree ()
std::pair< bool, RefCountedKinematicParticle >	motherParticle () const
bool	movePointerToTheFirstChild () const
bool	movePointerToTheMother () const
bool	movePointerToTheNextChild () const
void	movePointerToTheTop () const
void	replaceCurrentParticle (RefCountedKinematicParticle newPart) const
void	replaceCurrentVertex (RefCountedKinematicVertex newVert) const
RefCountedKinematicParticle	topParticle () const
virtual	~KinematicTree ()

Private Member Functions
void	leftBranchAdd (KinematicTree *otherTree, RefCountedKinematicVertex vtx)
bool	leftBranchSearch (RefCountedKinematicParticle part) const
bool	leftBranchVertexSearch (RefCountedKinematicVertex vtx) const
bool	leftFinalParticle () const

Private Attributes
bool	empt
graph < RefCountedKinematicVertex, RefCountedKinematicParticle >	treeGraph
graphwalker < RefCountedKinematicVertex, RefCountedKinematicParticle > *	treeWalker

Detailed Description

Class describing the decay chain inside the kinematic fit. Uses the boost graph based DDD library. KinematicVertices are vertices, kinemtaic particles become nodes.

Kirill Prokofiev, April 2003 WARNING: before using any of these methods please make sure you understand correctly what part of tree are you looking at now and where the pointer will be after the desiring operation.

"Left" and "Right" notation reflects the order of creating a three: from bottom to top, from left to right EXAMPLE: Bs->J/Psi Phi -> mumu KK First creating a mumu branch, fit it to J/Psi, Then adding Phi->KK and reconstructing a Bs will look like: left bottom particle: muon, top of the tree is Bs, right bottom is K.

Definition at line 36 of file KinematicTree.h.

Constructor & Destructor Documentation

KinematicTree::KinematicTree

(

)

Constructor initializing everything and setting all values to 0

Definition at line 3 of file KinematicTree.cc.

References empt, and treeWalker.

{
 empt = true;
 treeWalker = 0;
}

KinematicTree::~KinematicTree ( )

virtual

Definition at line 9 of file KinematicTree.cc.

References treeWalker.

{
 delete treeWalker;
}

Member Function Documentation

void KinematicTree::addParticle	(	RefCountedKinematicVertex	prodVtx,
		RefCountedKinematicVertex	decVtx,
		RefCountedKinematicParticle	part
	)

Methods adding nodes and edges to the graph representation of the Kinematic Tree

Definition at line 26 of file KinematicTree.cc.

References empt, movePointerToTheTop(), and treeGraph.

Referenced by addTree(), and leftBranchAdd().

{
 part->setTreePointer(this);
 treeGraph.addEdge(prodVtx,decVtx,part);
 empt = false;
 movePointerToTheTop();
 prodVtx->setTreePointer(this);
 decVtx->setTreePointer(this);
}

void KinematicTree::addTree	(	RefCountedKinematicVertex	vtx,
		KinematicTree *	tr
	)

Method adding a tree tr to the vertex vtx of current tree in such a way, that vtx become a production vertex for the top particle of the tr. The whole contetnts of tr is the rewritten to current tree. This method is purely technical and contains no mathematics. To be used by KinematicParticleVertexFitter after the corresponding fit.

Definition at line 432 of file KinematicTree.cc.

References addParticle(), currentDecayVertex(), currentParticle(), currentProductionVertex(), findDecayVertex(), leftBranchAdd(), movePointerToTheMother(), movePointerToTheNextChild(), movePointerToTheTop(), and up.

{
//adding new tree to the existing one:
 bool fnd = findDecayVertex(vtx);
 if(!fnd) throw VertexException("KinematicTree::addTree; Current tree does not contain the vertex passed");
 tr->movePointerToTheTop();
 
// adding the root of the tree: 
 RefCountedKinematicParticle mP = tr->currentParticle(); 
 RefCountedKinematicVertex   dec_vertex = tr->currentDecayVertex();
 addParticle(vtx,dec_vertex,mP);

// adding the left branch if any 
 leftBranchAdd(tr,dec_vertex);

//now the pointer is at the left down
//edge of the otherTree.
//current tree pointer is where the
//add operation was stoped last time.
 bool right = true;
 bool up = true;
 do
 {
  right = tr->movePointerToTheNextChild();
  if(right)
  {

//production vertex is already at the current tree  
//adding current partilce
   RefCountedKinematicVertex prodVertex = tr->currentProductionVertex();
   RefCountedKinematicParticle cPart = tr->currentParticle();
   RefCountedKinematicVertex decVertex = tr->currentDecayVertex();
   addParticle(prodVertex, decVertex, cPart);
   
//adding the rest of the branch   
   leftBranchAdd(tr,decVertex);
  }else{
   up = tr->movePointerToTheMother(); 
  }
 }while(up);
}           

RefCountedKinematicVertex KinematicTree::currentDecayVertex

(

)

const

Returns a current decay vertex pointer is NOT moved

Definition at line 107 of file KinematicTree.cc.

References isEmpty(), and treeWalker.

Referenced by addTree(), findDecayVertex(), leftBranchAdd(), leftBranchVertexSearch(), and replaceCurrentVertex().

 {
   if(isEmpty()) throw VertexException("KinematicTree::currentDecayVertex; tree is empty!");
   return treeWalker->current().first;
 }

RefCountedKinematicParticle KinematicTree::currentParticle

(

)

const

Returns a current particle pointer is NOT moved

Definition at line 229 of file KinematicTree.cc.

References isEmpty(), and treeWalker.

Referenced by addTree(), currentProductionVertex(), daughterParticles(), finalStateParticles(), findParticle(), leftBranchAdd(), leftBranchSearch(), and replaceCurrentParticle().

{
 if(isEmpty()) throw VertexException("KinematicTree::currentParticle; tree is empty!");
 return treeWalker->current().second;
}

RefCountedKinematicVertex KinematicTree::currentProductionVertex

(

)

const

Returns a current production vertex pointer is NOT moved

Definition at line 177 of file KinematicTree.cc.

References currentParticle(), down, isEmpty(), movePointerToTheMother(), GetRecoTauVFromDQM_MC_cff::next, treeGraph, treeWalker, and up.

Referenced by addTree(), and motherParticle().

{
  if(isEmpty()) throw VertexException("KinematicTree::currentProductionVertex; tree is empty!");
//current particle
  RefCountedKinematicParticle initial = currentParticle();
  
  bool up;
  bool down;
  RefCountedKinematicVertex res;
  up = movePointerToTheMother();
  
 if(up)
 { 
  res = treeWalker->current().first;
                                   
//pointer moved so we going back
  down = treeWalker->firstChild();
   
//_down_ variable is always TRUE here, if
//the tree is valid.
  if(down){
   if(initial == treeWalker->current().second)
   {
    return res;
   }else{
    bool next = true;
    do
    {
     next = treeWalker->nextSibling();
     if(treeWalker->current().second == initial) next = false;
    }while(next);
    return res;
   }
  }else{throw VertexException("KinematicTree::Navigation failed, tree invalid?");}          
 }else
 { 
//very unprobable case. This efectively means that user is
//already out of the tree. Moving back to the top
 delete treeWalker;
 treeWalker = new graphwalker<RefCountedKinematicVertex,
                              RefCountedKinematicParticle>
                                              (treeGraph);
 res = treeWalker->current().first;                       
//now pointer is a pair: fake vertex and 
//icoming 0 pointer to the particle
//moving it to decayed particle
 bool move = treeWalker->firstChild();
 if(!move) throw VertexException("KinematicTree::movePointerToTheTop; non consistent tree?");
 return res;
 } 
}

std::vector< RefCountedKinematicParticle > KinematicTree::daughterParticles

(

)

const

Returns a non-zero vector in case of success and 0 vector in case of failure Pointer is NOT moved

Definition at line 141 of file KinematicTree.cc.

References prof2calltree::back, currentParticle(), down, findParticle(), isEmpty(), and treeWalker.

 {
  if(isEmpty()) throw VertexException("KinematicTree::daughterParticles; tree is empty!");
  std::vector<RefCountedKinematicParticle> sResult;
  RefCountedKinematicParticle initial = currentParticle();
  bool down  = treeWalker->firstChild();
  if(down)
  {
    sResult.push_back(treeWalker->current().second);
    bool sibling = true;
    do
    {
     sibling = treeWalker->nextSibling();
     if(sibling) sResult.push_back(treeWalker->current().second); 
    }while(sibling);
  }

//getting the pointer back to the mother  
  bool back = findParticle(initial);
  if(!back) throw VertexException("KinematicTree::daughterParticles; error occured while getting back");
  return sResult;
 }

std::vector< RefCountedKinematicParticle > KinematicTree::finalStateParticles

(

)

const

Kinematic Tree navigation methods Returns the complete vector of final state particles for the whole decay tree. Pointer is NOT moved after this operation

Definition at line 38 of file KinematicTree.cc.

References prof2calltree::back, gather_cfg::cout, currentParticle(), findParticle(), isConsistent(), isEmpty(), leftFinalParticle(), movePointerToTheMother(), movePointerToTheNextChild(), movePointerToTheTop(), and up.

{
 if(isEmpty() || !(isConsistent()))
 {
  throw VertexException("KinematicTree::finalStateParticles; tree is empty or not consistent");
 }else{
  RefCountedKinematicParticle initial = currentParticle();
  std::vector<RefCountedKinematicParticle> rs;
  movePointerToTheTop();
  if(!(leftFinalParticle()))
  {
   std::cout<<"top particle has no daughters, empty vector returned"<<std::endl;
  }else{
//now pointer is at the  most left final particle
   rs.push_back(currentParticle()); 
   bool next_right = true; 
   bool up = true;
   do
   {
    next_right = movePointerToTheNextChild();
    if(next_right)
    {
//if there's a way to the right,
//we go right and down possible    
     leftFinalParticle();
     rs.push_back(currentParticle()); 
    }else{
//once there's no way to right anymore
//trying to find a way upper    
     up = movePointerToTheMother();
    }
//loop stops when we are at the top:
//no way up, no way to the right    
   }while(up);   
  } 
//getting the pointer back  
  bool back = findParticle(initial);
  if(!back) throw VertexException("KinematicTree::FinalStateParticles; error occured while getting back");
  return rs;
 }
}

bool KinematicTree::findDecayVertex

(

const RefCountedKinematicVertex

vert

)

const

Pointer goes to the particle for which the neede vertex will be the decay one (true case) Or pointer stays at the top of teh tree if search is unsuccessfull (false case).

Definition at line 312 of file KinematicTree.cc.

References currentDecayVertex(), isConsistent(), isEmpty(), leftBranchVertexSearch(), movePointerToTheMother(), movePointerToTheNextChild(), movePointerToTheTop(), and up.

Referenced by addTree().

{
 if(isEmpty() || !(isConsistent()))
 {
  throw VertexException("KinematicTree::findParticle; tree is empty or not consistent");
 }else{
 bool res = false;
 movePointerToTheTop();
 if(currentDecayVertex() == vert)
 {
  res = true;
 }else if(leftBranchVertexSearch(vert)){
  res = true;
 }else{
  bool up = true;
  bool fnd = false;
  do
  {
   if(movePointerToTheNextChild())
   {
    fnd = leftBranchVertexSearch(vert);
   }else{
    up=movePointerToTheMother();
    if(currentDecayVertex() == vert) fnd = true;
   }   
  }while(up && !fnd);
  res = fnd;
 }
 return res;
 }
}

bool KinematicTree::findDecayVertex

(

KinematicVertex *

vert

)

const

Definition at line 344 of file KinematicTree.cc.

References currentDecayVertex(), isConsistent(), isEmpty(), leftBranchVertexSearch(), movePointerToTheMother(), movePointerToTheNextChild(), movePointerToTheTop(), and up.

{
 if(isEmpty() || !(isConsistent()))
 {
  throw VertexException("KinematicTree::findParticle; tree is empty or not consistent");
 }else{
 bool res = false;
 movePointerToTheTop();
 if(*currentDecayVertex() == vert)
 {
  res = true;
 }else if(leftBranchVertexSearch(vert)){
  res = true;
 }else{
  bool up = true;
  bool fnd = false;
  do
  {
   if(movePointerToTheNextChild())
   {
    fnd = leftBranchVertexSearch(vert);
   }else{
    up=movePointerToTheMother();
    if(currentDecayVertex() == vert) fnd = true;
   }   
  }while(up && !fnd);
  res = fnd;
 }
 return res;
 }
}

bool KinematicTree::findParticle

(

const RefCountedKinematicParticle

part

)

const

Pointer goes to the needed particle inside the tree if found (true). Pointer goes to the top of the tree if not found (false)

Definition at line 256 of file KinematicTree.cc.

References currentParticle(), newFWLiteAna::found, isConsistent(), isEmpty(), leftBranchSearch(), movePointerToTheMother(), movePointerToTheNextChild(), movePointerToTheTop(), and up.

Referenced by daughterParticles(), and finalStateParticles().

{
 if(isEmpty() || !(isConsistent()))
 {
  throw VertexException("KinematicTree::findParticle; tree is empty or not consistent");
 }else{
  bool res = false;
  movePointerToTheTop();
  if(currentParticle() == part)
  {
   res = true;
  }else if(leftBranchSearch(part)){
   res = true;
  }else{
   bool found = false;
   bool up = true;
   bool next_right = false;
   do
   {
//    if(*(currentParticle()) == *part) found = true;
    next_right = movePointerToTheNextChild();
    if(next_right)
    {
     found = leftBranchSearch(part);
    }else{
     up = movePointerToTheMother();
     if(currentParticle() == part) found = true;
    }
   }while(up && !found);
   res = found;
  } 
  return res;
 }
}

bool KinematicTree::isConsistent

(

)

const

This method checks if the tree is consistent, i.e. the top vertex is only one.

Definition at line 18 of file KinematicTree.cc.

References movePointerToTheTop(), and treeWalker.

Referenced by finalStateParticles(), findDecayVertex(), and findParticle().

{
 movePointerToTheTop();
 bool des = false;
 if(!treeWalker->nextSibling()) des = true;
 return des;
}

bool KinematicTree::isEmpty

(

void

)

const

Access methods

Definition at line 15 of file KinematicTree.cc.

References empt.

Referenced by currentDecayVertex(), currentParticle(), currentProductionVertex(), daughterParticles(), finalStateParticles(), findDecayVertex(), findParticle(), motherParticle(), movePointerToTheFirstChild(), movePointerToTheMother(), movePointerToTheNextChild(), movePointerToTheTop(), and topParticle().

 {return empt;}

bool KinematicTree::isValid ( void  ) const

inline

Definition at line 53 of file KinematicTree.h.

References empt.

Referenced by core.AutoHandle.AutoHandle::ReallyLoad().

{return !empt;}

void KinematicTree::leftBranchAdd ( KinematicTree *  otherTree, RefCountedKinematicVertex  vtx  )

private

Definition at line 396 of file KinematicTree.cc.

References addParticle(), currentDecayVertex(), currentParticle(), movePointerToTheFirstChild(), and GetRecoTauVFromDQM_MC_cff::next.

Referenced by addTree().

{
  RefCountedKinematicVertex previous_decay = otherTree->currentDecayVertex(); 
 
//children of current particle of the
//other tree: in the end the whole 
//left branch should be added. 
  bool next = true;
  do
  {
   next = otherTree->movePointerToTheFirstChild();
   if(next)
   {
    RefCountedKinematicParticle par = otherTree->currentParticle();
    RefCountedKinematicVertex current_decay = otherTree->currentDecayVertex();
    addParticle(previous_decay, current_decay, par);
    previous_decay = current_decay;
   }
  }while(next);
}

bool KinematicTree::leftBranchSearch ( RefCountedKinematicParticle  part ) const

private

Private methods to walk around the tree: Needed to collect final state or particle search.

Definition at line 292 of file KinematicTree.cc.

References currentParticle(), newFWLiteAna::found, movePointerToTheFirstChild(), and GetRecoTauVFromDQM_MC_cff::next.

Referenced by findParticle().

{
 bool found = false;
 bool next = true;
 if(currentParticle() == part)
 {
  found = true;
 }else{
  do
  {
   next = movePointerToTheFirstChild();
   if(currentParticle() == part)
   {
    found = true;
   }
  }while(next && !found);
  }
 return found;
}

bool KinematicTree::leftBranchVertexSearch ( RefCountedKinematicVertex  vtx ) const

private

Definition at line 377 of file KinematicTree.cc.

References currentDecayVertex(), newFWLiteAna::found, movePointerToTheFirstChild(), and GetRecoTauVFromDQM_MC_cff::next.

Referenced by findDecayVertex().

{
 bool found = false;
 if(currentDecayVertex() == vtx)
 {
  found = true;
 }else{
  bool next = true;
  bool res = false;
  do
  {
   next = movePointerToTheFirstChild();
   if(currentDecayVertex() == vtx) res = true;
  }while(next && !res); 
  found  = res;
 }
 return found;
}

bool KinematicTree::leftFinalParticle ( ) const

private

Definition at line 80 of file KinematicTree.cc.

References movePointerToTheFirstChild(), and GetRecoTauVFromDQM_MC_cff::next.

Referenced by finalStateParticles().

{
 bool res = false;
 if(movePointerToTheFirstChild())
 {
  res = true;
  bool next = true;
  do
  {
    next = movePointerToTheFirstChild(); 
  }while(next);
 }else{
  res =false;
 }
 return res;
}

std::pair< bool, RefCountedKinematicParticle > KinematicTree::motherParticle

(

)

const

Returns true and state of mother particle if successfull, false and state of current particle in case of failure Pointer is NOT moved.

Definition at line 113 of file KinematicTree.cc.

References currentProductionVertex(), benchmark_cfg::fc, isEmpty(), treeWalker, and up.

 {
  if(isEmpty()) throw VertexException("KinematicTree::motherParticle; tree is empty!");
  bool top = currentProductionVertex()->vertexIsValid();
   RefCountedKinematicParticle cr  = treeWalker->current().second;
   bool up = treeWalker->parent();
   std::pair<bool,RefCountedKinematicParticle> res; 
   if(up && top){
    RefCountedKinematicParticle pr = treeWalker->current().second;
    
//now putting the pointer back   
    bool fc = treeWalker->firstChild();
    if(!fc) throw VertexException("KinematicTree::motherParticle; tree is incorrect!");
    if(*(treeWalker->current().second) != *cr)
    {
     do{
      bool nx = treeWalker->nextSibling();
      if(!nx) throw VertexException("KinematicTree::motherParticle; tree is incorrect!");
     }while(*(treeWalker->current().second) != *cr);
    }
    res = std::pair<bool,RefCountedKinematicParticle>(true,pr);
    return res;
   }else{
    RefCountedKinematicParticle fk;
    return std::pair<bool,RefCountedKinematicParticle>(false,fk);
   }
 }

bool KinematicTree::movePointerToTheFirstChild

(

)

const

Pointer goes to the first child(if any) in the list

Definition at line 243 of file KinematicTree.cc.

References isEmpty(), and treeWalker.

Referenced by leftBranchAdd(), leftBranchSearch(), leftBranchVertexSearch(), and leftFinalParticle().

{
 if(isEmpty()) throw VertexException("KinematicTree::movePointerToTheFirstChild; tree is empty!");
 return treeWalker->firstChild();
}

bool KinematicTree::movePointerToTheMother

(

)

const

Pointer goes to the mother particle (if any) with respest to the current one

Definition at line 235 of file KinematicTree.cc.

References isEmpty(), treeWalker, and up.

Referenced by addTree(), currentProductionVertex(), finalStateParticles(), findDecayVertex(), and findParticle().

{
 if(isEmpty()) throw VertexException("KinematicTree::movePointerToTheMother; tree is empty!");
 bool up = treeWalker->parent();
 bool cr = treeWalker->current().first->vertexIsValid();
 return (up && cr);
}

bool KinematicTree::movePointerToTheNextChild

(

)

const

Pointer goes to the next child in the list (if any)

Definition at line 249 of file KinematicTree.cc.

References isEmpty(), and treeWalker.

Referenced by addTree(), finalStateParticles(), findDecayVertex(), and findParticle().

{
 if(isEmpty()) throw VertexException("KinematicTree::movePointerToTheNextChild; tree is empty!");
 bool res = treeWalker->nextSibling();
 return res;
}

void KinematicTree::movePointerToTheTop

(

)

const

Puts the pointer to the top (root) of the tree. The Graph walker object gets recreated inside the tree.

Definition at line 164 of file KinematicTree.cc.

References isEmpty(), treeGraph, and treeWalker.

Referenced by addParticle(), addTree(), ConstrainedTreeBuilderT::buildRealTree(), FinalTreeBuilder::buildTree(), ConstrainedTreeBuilder::buildTree(), finalStateParticles(), findDecayVertex(), findParticle(), isConsistent(), and topParticle().

{
 if(isEmpty()) throw VertexException("KinematicTree::movePointerToTheTop; tree is empty!");
 delete treeWalker;
 treeWalker = new graphwalker<RefCountedKinematicVertex,
                              RefCountedKinematicParticle>(treeGraph);
//now pointer is a pair: fake vertex and 
//icoming 0 pointer to the particle
//moving it to decayed particle
 bool move = treeWalker->firstChild();
 if(!move) throw VertexException("KinematicTree::movePointerToTheTop; non consistent tree?");
}

void KinematicTree::replaceCurrentParticle

(

RefCountedKinematicParticle

newPart

)

const

Methods replacing Particles and Vertices inside the tree during the refit. Methods should used by corresponding KinematicFitter classe only. Replace the current track or current (decay) vertex WARNING: replace methods are not available at this version of KinematicFitPrimitives.

Definition at line 417 of file KinematicTree.cc.

References currentParticle(), python.rootplot.root2matplotlib::replace(), and treeGraph.

Referenced by ConstrainedTreeBuilderT::buildRealTree(), FinalTreeBuilder::buildTree(), and ConstrainedTreeBuilder::buildTree().

{
 RefCountedKinematicParticle cDParticle = currentParticle();
 bool replace = treeGraph.replaceEdge(cDParticle,newPart);
 if(!replace) throw VertexException("KinematicTree::Particle To Replace not found");
}

void KinematicTree::replaceCurrentVertex

(

RefCountedKinematicVertex

newVert

)

const

Replaces decay vertex of the current particle with the given value

Definition at line 424 of file KinematicTree.cc.

References currentDecayVertex(), python.rootplot.root2matplotlib::replace(), and treeGraph.

{
 RefCountedKinematicVertex cDVertex = currentDecayVertex();
 bool replace = treeGraph.replace(cDVertex,newVert);
 if(! replace) throw VertexException("KinematicTree::Vertex To Replace not found");
}

RefCountedKinematicParticle KinematicTree::topParticle

(

)

const

Returns the top particle of decay. Pointer is moved to the TOP of the decay tree.

Definition at line 98 of file KinematicTree.cc.

References isEmpty(), movePointerToTheTop(), and treeWalker.

 {
   if(isEmpty()) throw VertexException("KinematicTree::topParticle; tree is empty!");
//putting pointer to the top of the tree 
   movePointerToTheTop();
   return treeWalker->current().second;                     
 }

Member Data Documentation

bool KinematicTree::empt

mutableprivate

Definition at line 213 of file KinematicTree.h.

Referenced by addParticle(), isEmpty(), isValid(), and KinematicTree().

graph<RefCountedKinematicVertex,RefCountedKinematicParticle> KinematicTree::treeGraph

mutableprivate

Definition at line 215 of file KinematicTree.h.

Referenced by addParticle(), currentProductionVertex(), movePointerToTheTop(), replaceCurrentParticle(), and replaceCurrentVertex().

graphwalker<RefCountedKinematicVertex, RefCountedKinematicParticle>* KinematicTree::treeWalker

mutableprivate

Definition at line 216 of file KinematicTree.h.

Referenced by currentDecayVertex(), currentParticle(), currentProductionVertex(), daughterParticles(), isConsistent(), KinematicTree(), motherParticle(), movePointerToTheFirstChild(), movePointerToTheMother(), movePointerToTheNextChild(), movePointerToTheTop(), topParticle(), and ~KinematicTree().