TSpider.cxx

Go to the documentation of this file.

// @(#)root/treeviewer:$Id: 2bb6def14de16b049d4c979e73ad2b08d0936520 $
// Author: Bastien Dalla Piazza  20/07/07
 
/*************************************************************************
 * Copyright (C) 1995-2007, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/
 
#include "TSpider.h"
#include "TAttFill.h"
#include "TAttText.h"
#include "TAttLine.h"
#include "TGraphPolargram.h"
#include "TPolyLine.h"
#include "TNtuple.h"
#include "TBranch.h"
#include "TTreeFormula.h"
#include "TTreeFormulaManager.h"
#include "TList.h"
#include "TSelectorDraw.h"
#include "TROOT.h"
#include "TEntryList.h"
#include "TLatex.h"
#include "TVirtualPad.h"
#include "TMath.h"
#include "TCanvas.h"
#include "TArc.h"
#include <cfloat>
#include "TEnv.h"
 
 
/** \class TSpider
Spider class.
 
A spider view is a handy way to visualize a set of data stored in a TTree.
It draws as many polar axes as selected data members. For each of them, it draws
on the axis the position of the present event between the min and max of the
data member. Two modes are available:
 
  - The spider view: With each points on the axes is drawn a polyline.
  - The segment view: For each data member is drawn an arc segment with the
    radius corresponding to the event.
 
The spider plot is available from the treeviewer called by
"atree->StartViewer()", or simply by calling its constructor and defining the
variables to display.
 
Begin_Macro(source)
{
   TCanvas *c1 = new TCanvas("c1","TSpider example",200,10,700,700);
   TFile *f = new TFile("$(ROOTSYS)/tutorials/hsimple.root");
   if (!f || f->IsZombie()) {
      printf("Please run <ROOT location>/tutorials/hsimple.C before.");
      return;
   }
   TNtuple* ntuple = (TNtuple*)f->Get("ntuple");
   TString varexp = "px:py:pz:random:sin(px):log(px/py):log(pz)";
   TString selectStr = "px>0 && py>0 && pz>0";
   TString options = "average";
   TSpider *spider = new TSpider(ntuple,varexp.Data(),selectStr.Data(),options.Data());
   spider->Draw();
   c1->ToggleEditor();
   c1->Selected(c1,spider,1);
   return c1;
}
End_Macro
*/
 
////////////////////////////////////////////////////////////////////////////////
/// Default constructor.
 
TSpider::TSpider()
{
   fDisplayAverage=false;
   fForceDim=false;
   fPolargram=nullptr;
   fInput=nullptr;
   fManager=nullptr;
   fNcols=0;
   fNx=3;
   fNy=4;
   fPolyList=nullptr;
   fSelect=nullptr;
   fSelector=nullptr;
   fTree=nullptr;
   fMax=nullptr;
   fMin=nullptr;
   fAve=nullptr;
   fCanvas=nullptr;
   fAveragePoly=nullptr;
   fEntry=0;
   fSuperposed=nullptr;
   fShowRange=false;
   fAngularLabels=false;
   fAverageSlices=nullptr;
   fSegmentDisplay=false;
   fNentries=0;
   fFirstEntry=0;
   fArraySize=0;
   fCurrentEntries = nullptr;
   fFormulas = nullptr;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Normal constructor. Options are:
///  - "average"
///  - "showrange"
///  - "segment"
 
TSpider::TSpider(TTree* tree ,const char *varexp, const char *selection,
                               Option_t *option, Long64_t nentries, Long64_t firstentry)
   : TAttFill(2,3003), TAttLine(1,1,1)
{
   UInt_t ui=0;
 
   fArraySize = 16;
   fTree=tree;
   fSelector= new TSelectorDraw();
   fFormulas= new TList();
   fInput= new TList();
   fInput->Add(new TNamed("varexp",""));
   fInput->Add(new TNamed("selection",""));
   fSelector->SetInputList(fInput);
   gROOT->GetListOfCleanups()->Add(this);
   fNx=2;
   fNy=2;
   fDisplayAverage=false;
   fSelect=nullptr;
   fManager=nullptr;
   fCanvas=nullptr;
   fAveragePoly=nullptr;
   fEntry=fFirstEntry;
   fSuperposed=nullptr;
   fShowRange=false;
   fAngularLabels=true;
   fForceDim=false;
   fAverageSlices=nullptr;
   fSegmentDisplay=false;
   if (firstentry < 0 || firstentry > tree->GetEstimate()) firstentry = 0;
   fFirstEntry = firstentry;
   if (nentries>0) fNentries = nentries;
   else fNentries = nentries = tree->GetEstimate()-firstentry;
 
   fEntry = fFirstEntry;
 
   fPolargram=nullptr;
   fPolyList=nullptr;
 
   fTree->SetScanField(fNx*fNy);
   fCurrentEntries = new Long64_t[fNx*fNy];
   for(ui=0;ui<fNx*fNy;++ui) fCurrentEntries[ui]=0;
 
   TString opt = option;
 
   if (opt.Contains("average")) fDisplayAverage=true;
   if (opt.Contains("showrange")) fShowRange=true;
   if (opt.Contains("segment")) fSegmentDisplay=true;
 
   fNcols=8;
 
   SetVariablesExpression(varexp);
   SetSelectionExpression(selection);
   SyncFormulas();
   InitVariables(firstentry,nentries);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Destructor.
 
TSpider::~TSpider()
{
   delete [] fCurrentEntries;
   if(fPolyList){
      fPolyList->Delete();
      delete fPolyList;
   }
   if(fAverageSlices)
      delete [] fAverageSlices;
   if(fFormulas){
      fFormulas->Delete();
      delete fFormulas;
   }
   if(fSelect) delete fSelect;
   if(fSelector) delete fSelector;
   if(fInput){
      fInput->Delete();
      delete fInput;
   }
   if(fMax) delete [] fMax;
   if(fMin) delete [] fMin;
   if(fAve) delete [] fAve;
   if(fSuperposed){
      fSuperposed->Delete();
      delete fSuperposed;
   }
   if (fCanvas) fCanvas->cd(0);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Allow to superpose several spider views.
 
void TSpider::AddSuperposed(TSpider* sp)
{
   if(!fSuperposed) fSuperposed=new TList();
   fSuperposed->Add(sp);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Add a variable to the plot from its expression.
 
void TSpider::AddVariable(const char* varexp)
{
   if(!varexp[0]) return;
   TTreeFormula *fvar = new TTreeFormula("Var1",varexp,fTree);
   if(fvar->GetNdim() <= 0) return;
 
   fFormulas->AddAfter(fFormulas->At(fNcols-1),fvar);
 
   InitArrays(fNcols + 1);
   ++fNcols;
   SyncFormulas();
 
   UInt_t ui=0;
   Long64_t notSkipped=0;
   Int_t tnumber=-1;
   Long64_t entryNumber;
   Long64_t entry = fFirstEntry;
   Int_t entriesToDisplay = fNentries;
   while(entriesToDisplay!=0){
      entryNumber = fTree->GetEntryNumber(entry);
      if(entryNumber < 0) break;
      Long64_t localEntry = fTree->LoadTree(entryNumber);
      if(localEntry < 0) break;
      if(tnumber != fTree->GetTreeNumber()) {
         tnumber = fTree->GetTreeNumber();
         if(fManager) fManager->UpdateFormulaLeaves();
         else {
            for(Int_t i=0;i<=fFormulas->LastIndex();++i)
               ((TTreeFormula*)fFormulas->At(i))->UpdateFormulaLeaves();
         }
      }
      Int_t ndata=1;
      if(fForceDim){
         if(fManager)
            ndata = fManager->GetNdata(true);
         else {
            for(ui=0;ui<fNcols;++ui){
               if(ndata<((TTreeFormula*)fFormulas->At(ui))->GetNdata())
                  ndata = ((TTreeFormula*)fFormulas->At(ui))->GetNdata();
            }
            if(fSelect && fSelect->GetNdata() == 0)
               ndata = 0;
         }
      }
 
      bool loaded = false;
      bool skip = false;
      // Loop over the instances of the selection condition
      for(Int_t inst=0;inst<ndata;++inst){
         if(fSelect){
            if(fSelect->EvalInstance(inst) == 0){
               skip = true;
               ++entry;
            }
         }
         if (!loaded) {
            // EvalInstance(0) always needs to be called so that
            // the proper branches are loaded.
            ((TTreeFormula*)fFormulas->At(fNcols-1))->EvalInstance(0);
            loaded = true;
         } else if (inst == 0) {
            loaded = true;
         }
      }
      if(!skip){
         fTree->LoadTree(entryNumber);
         TTreeFormula* var = (TTreeFormula*)fFormulas->At(fNcols-1);
         if(var->EvalInstance()>fMax[fNcols-1]) fMax[fNcols-1]=var->EvalInstance();
         if(var->EvalInstance()<fMin[fNcols-1]) fMin[fNcols-1]=var->EvalInstance();
         fAve[fNcols-1]+=var->EvalInstance();
         ++notSkipped;
         --entriesToDisplay;
         ++entry;
      }
   }
   if (notSkipped) fAve[fNcols-1]/=notSkipped;
 
   Color_t lc;
   Style_t lt;
   Width_t lw;
   Color_t fc;
   Style_t fs;
 
   if(fAverageSlices){
      lc = fAverageSlices[0]->GetLineColor();
      lt = fAverageSlices[0]->GetLineStyle();
      lw = fAverageSlices[0]->GetLineWidth();
      fc = fAverageSlices[0]->GetFillColor();
      fs = fAverageSlices[0]->GetFillStyle();
   } else {
      lc = fAveragePoly->GetLineColor();
      lt = fAveragePoly->GetLineStyle();
      lw = fAveragePoly->GetLineWidth();
      fc = fAveragePoly->GetFillColor();
      fs = fAveragePoly->GetFillStyle();
   }
 
   delete fPolargram;
   fPolargram = nullptr;
 
   if(fSegmentDisplay){
      for(ui=0;ui<fNx*fNy;++ui) ((TList*)fPolyList->At(ui))->Delete();
      if (fAverageSlices) for(ui=0;ui<fNcols-1;++ui) delete fAverageSlices[ui];
   }
   fPolyList->Delete();
   delete fPolyList;
   fPolyList = nullptr;
   delete [] fAverageSlices;
   fAverageSlices = nullptr;
   delete fAveragePoly;
   fAveragePoly = nullptr;
 
   if (fCanvas) {
      fCanvas->Clear();
      fCanvas->Divide(fNx,fNy);
   }
   Draw("");
 
   if(fAverageSlices){
      for(ui = 0;ui<fNcols;++ui){
         fAverageSlices[ui]->SetLineColor(lc);
         fAverageSlices[ui]->SetLineStyle(lt);
         fAverageSlices[ui]->SetLineWidth(lw);
         fAverageSlices[ui]->SetFillColor(fc);
         fAverageSlices[ui]->SetFillStyle(fs);
      }
   } else {
      fAveragePoly->SetLineColor(lc);
      fAveragePoly->SetLineStyle(lt);
      fAveragePoly->SetLineWidth(lw);
      fAveragePoly->SetFillColor(fc);
      fAveragePoly->SetFillStyle(fs);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Delete a variable from its expression.
 
void TSpider::DeleteVariable(const char* varexp)
{
   Int_t var=-1;
   UInt_t ui=0;
 
   if(fNcols == 2) return;
   for(ui=0; ui<fNcols;++ui){
      if(!strcmp(varexp,((TTreeFormula*)fFormulas->At(ui))->GetTitle())) var = ui;
   }
   if(var<0) return;
 
   fFormulas->Remove(fFormulas->At(var));
   SyncFormulas();
 
   for(ui=var+1;ui<fNcols;++ui){
      fMin[ui-1] = fMin[ui];
      fMax[ui-1] = fMax[ui];
      fAve[ui-1] = fAve[ui];
   }
   fMin[fNcols-1] = DBL_MAX;
   fMax[fNcols-1] = -DBL_MAX;
   fAve[fNcols-1] = 0;
   --fNcols;
 
   Color_t lc;
   Style_t lt;
   Width_t lw;
   Color_t fc;
   Style_t fs;
 
   if(fAverageSlices){
      lc = fAverageSlices[0]->GetLineColor();
      lt = fAverageSlices[0]->GetLineStyle();
      lw = fAverageSlices[0]->GetLineWidth();
      fc = fAverageSlices[0]->GetFillColor();
      fs = fAverageSlices[0]->GetFillStyle();
   } else {
      lc = fAveragePoly->GetLineColor();
      lt = fAveragePoly->GetLineStyle();
      lw = fAveragePoly->GetLineWidth();
      fc = fAveragePoly->GetFillColor();
      fs = fAveragePoly->GetFillStyle();
   }
 
   delete fPolargram;
   fPolargram = nullptr;
 
   if(fSegmentDisplay){
      for(ui=0;ui<fNx*fNy;++ui) ((TList*)fPolyList->At(ui))->Delete();
      if (fAverageSlices) for(ui=0;ui<=fNcols;++ui) delete fAverageSlices[ui];
   }
   fPolyList->Delete();
   delete fPolyList;
   fPolyList = nullptr;
   delete [] fAverageSlices;
   fAverageSlices = nullptr;
   delete fAveragePoly;
   fAveragePoly = nullptr;
 
   if (fCanvas) {
      fCanvas->Clear();
      fCanvas->Divide(fNx,fNy);
   }
   Draw("");
   if(fNcols == 2) SetSegmentDisplay(true);
 
   if(fAverageSlices){
      for(ui = 0;ui<fNcols;++ui){
         fAverageSlices[ui]->SetLineColor(lc);
         fAverageSlices[ui]->SetLineStyle(lt);
         fAverageSlices[ui]->SetLineWidth(lw);
         fAverageSlices[ui]->SetFillColor(fc);
         fAverageSlices[ui]->SetFillStyle(fs);
      }
   } else {
      fAveragePoly->SetLineColor(lc);
      fAveragePoly->SetLineStyle(lt);
      fAveragePoly->SetLineWidth(lw);
      fAveragePoly->SetFillColor(fc);
      fAveragePoly->SetFillStyle(fs);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Compute the distance to the spider.
 
Int_t TSpider::DistancetoPrimitive(Int_t px, Int_t py)
{
   if(!gPad) return 9999;
   Double_t xx,yy,r2;
   xx=gPad->AbsPixeltoX(px);
   yy=gPad->AbsPixeltoY(py);
   r2 = xx*xx + yy*yy;
   if(r2>1 && r2<1.5)
      return 0;
   else return 9999;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Draw the spider.
 
void TSpider::Draw(Option_t *options)
{
   UInt_t ui=0;
 
   gEnv->SetValue("Canvas.ShowEditor",1);
   if(!gPad && !fCanvas){
      fCanvas = new TCanvas("screen","Spider Plot",fNx*256,fNy*256);
      if (fCanvas) fCanvas->Divide(fNx,fNy);
   } else if(!fCanvas){
      fCanvas = (TCanvas*)gPad;
      if (fCanvas) fCanvas->Divide(fNx,fNy);
   }
   if(fPolargram) delete fPolargram;
   fPolargram=new TGraphPolargram("fPolargram");
   fPolargram->SetNdivPolar(fNcols);
   fPolargram->SetNdivRadial(0);
   if (fCanvas) fCanvas->cd();
   SetCurrentEntries();
   AppendPad(options);
   for(ui=0;ui<fNx*fNy;++ui){
      if (fCanvas) fCanvas->cd(ui+1);
      fPolargram->Draw("pn");
      fTree->LoadTree(fCurrentEntries[ui]);
      if(fSegmentDisplay){
         if(fDisplayAverage) DrawSlicesAverage("");
         DrawSlices("");
      } else {
         if(fDisplayAverage) DrawPolyAverage("");
         DrawPoly("");
      }
      AppendPad();
   }
   if (fCanvas) fCanvas->Selected(fCanvas,this,1);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Paint the Polygon representing the average value of the variables.
 
void TSpider::DrawPolyAverage(Option_t* /*options*/)
{
   Int_t linecolor=4;
   Int_t fillstyle=0;
   Int_t fillcolor=linecolor;
   Int_t linewidth=1;
   Int_t linestyle=1;
 
   UInt_t ui=0;
   Double_t slice = 2*TMath::Pi()/fNcols;
   Double_t *x = new Double_t[fNcols+1];
   Double_t *y = new Double_t[fNcols+1];
 
   for(ui=0;ui<fNcols;++ui){
      x[ui]=(fAve[ui]-fMin[ui])/(fMax[ui]-fMin[ui])*TMath::Cos(ui*slice);
      y[ui]=(fAve[ui]-fMin[ui])/(fMax[ui]-fMin[ui])*TMath::Sin(ui*slice);
   }
   x[fNcols]=(fAve[0]-fMin[0])/(fMax[0]-fMin[0]);
   y[fNcols]=0;
 
   if(!fAveragePoly){
      fAveragePoly = new TPolyLine(fNcols+1,x,y);
      fAveragePoly->SetLineColor(linecolor);
      fAveragePoly->SetLineWidth(linewidth);
      fAveragePoly->SetLineStyle(linestyle);
      fAveragePoly->SetFillStyle(fillstyle);
      fAveragePoly->SetFillColor(fillcolor);
   }
   fAveragePoly->Draw();
   fAveragePoly->Draw("f");
 
   delete [] x;
   delete [] y;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Paint the polygon representing the current entry.
 
void TSpider::DrawPoly(Option_t* /*options*/)
{
   if(!fPolyList) fPolyList = new TList();
   Double_t *x = new Double_t[fNcols+1];
   Double_t *y = new Double_t[fNcols+1];
 
   Double_t slice = 2*TMath::Pi()/fNcols;
   for(UInt_t i=0;i<fNcols;++i){
      x[i]=(((TTreeFormula*)fFormulas->At(i))->EvalInstance()-fMin[i])/(fMax[i]-fMin[i])*TMath::Cos(i*slice);
      y[i]=(((TTreeFormula*)fFormulas->At(i))->EvalInstance()-fMin[i])/(fMax[i]-fMin[i])*TMath::Sin(i*slice);
   }
   x[fNcols]=(((TTreeFormula*)fFormulas->At(0))->EvalInstance()-fMin[0])/(fMax[0]-fMin[0]);
   y[fNcols]=0;
 
   TPolyLine* poly= new TPolyLine(fNcols+1,x,y);
   poly->SetFillColor(GetFillColor());
   poly->SetFillStyle(GetFillStyle());
   poly->SetLineWidth(GetLineWidth());
   poly->SetLineColor(GetLineColor());
   poly->SetLineStyle(GetLineStyle());
   poly->Draw("f");
   poly->Draw();
   fPolyList->Add(poly);
   delete [] x;
   delete [] y;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Draw the slices of the segment plot.
 
void TSpider::DrawSlices(Option_t* options)
{
   UInt_t ui=0;
 
   Double_t angle = 2*TMath::Pi()/fNcols;
   Double_t conv = 180.0/TMath::Pi();
 
   if(!fPolyList) fPolyList = new TList;
   TList* li = new TList();
   for(ui=0;ui<fNcols;++ui){
      Double_t r = (((TTreeFormula*)fFormulas->At(ui))->EvalInstance()-fMin[ui])/(fMax[ui]-fMin[ui]);
      TArc* slice = new TArc(0,0,r,(ui-0.25)*angle*conv,(ui+0.25)*angle*conv);
      slice->SetFillColor(GetFillColor());
      slice->SetFillStyle(GetFillStyle());
      slice->SetLineWidth(GetLineWidth());
      slice->SetLineColor(GetLineColor());
      slice->SetLineStyle(GetLineStyle());
      li->Add(slice);
      slice->Draw(options);
   }
   fPolyList->Add(li);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Draw the slices representing the average for the segment plot.
 
void TSpider::DrawSlicesAverage(Option_t* /*options*/)
{
   UInt_t ui=0;
 
   Int_t fillstyle=3002;
   Int_t linecolor=4;
   Int_t fillcolor=linecolor;
   Int_t linewidth=1;
   Int_t linestyle=1;
 
   Double_t angle = 2*TMath::Pi()/fNcols;
   Double_t conv = 180.0/TMath::Pi();
 
   if(!fAverageSlices){
      fAverageSlices = new TArc*[fNcols];
      for(ui=0;ui<fNcols;++ui){
         Double_t r = (fAve[ui]-fMin[ui])/(fMax[ui]-fMin[ui]);
         fAverageSlices[ui] = new TArc(0,0,r,(ui-0.5)*angle*conv,(ui+0.5)*angle*conv);
         fAverageSlices[ui]->SetFillColor(fillcolor);
         fAverageSlices[ui]->SetFillStyle(fillstyle);
         fAverageSlices[ui]->SetLineWidth(linewidth);
         fAverageSlices[ui]->SetLineColor(linecolor);
         fAverageSlices[ui]->SetLineStyle(linestyle);
      }
   }
   for(ui=0;ui<fNcols;++ui) fAverageSlices[ui]->Draw();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get the LineStyle of the average.
 
Style_t TSpider::GetAverageLineStyle() const
{
   if(fAverageSlices) return fAverageSlices[0]->GetLineStyle();
   else if(fAveragePoly) return fAveragePoly->GetLineStyle();
   else return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get the LineColor of the average.
 
Color_t TSpider::GetAverageLineColor() const
{
   if(fAverageSlices) return fAverageSlices[0]->GetLineColor();
   else if(fAveragePoly) return fAveragePoly->GetLineColor();
   else return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get the LineWidth of the average.
 
Width_t TSpider::GetAverageLineWidth() const
{
   if(fAverageSlices) return fAverageSlices[0]->GetLineWidth();
   else if(fAveragePoly) return fAveragePoly->GetLineWidth();
   else return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get the Fill Color of the average.
 
Color_t TSpider::GetAverageFillColor() const
{
   if(fAverageSlices) return fAverageSlices[0]->GetFillColor();
   else if(fAveragePoly) return fAveragePoly->GetFillColor();
   else return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Get the FillStyle of the average.
 
Style_t TSpider::GetAverageFillStyle() const
{
   if(fAverageSlices) return fAverageSlices[0]->GetFillStyle();
   else if(fAveragePoly) return fAveragePoly->GetFillStyle();
   else return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Execute the corresponding event.
 
void TSpider::ExecuteEvent(Int_t /*event*/,Int_t /*px*/, Int_t /*py*/)
{
   if (!gPad) return;
   gPad->SetCursor(kHand);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Find the alignement rule to apply for TText::SetTextAlign(Short_t).
 
Int_t TSpider::FindTextAlign(Double_t angle)
{
   Double_t pi = TMath::Pi();
 
   while(angle < 0 || angle > 2*pi){
      if(angle < 0) angle+=2*pi;
      if(angle > 2*pi) angle-=2*pi;
   }
   if(!fAngularLabels){
      if(angle > 0 && angle < pi/2) return 11;
      else if(angle > pi/2 && angle < pi) return 31;
      else if(angle > pi && angle < 3*pi/2) return 33;
      else if(angle > 3*pi/2 && angle < 2*pi) return 13;
      else if(angle == 0 || angle == 2*pi) return 12;
      else if(angle == pi/2) return 21;
      else if(angle == pi) return 32;
      else if(angle == 3*pi/2) return 23;
      else return 0;
   }
   else{
      if(angle >= 0 && angle < pi) return 21;
      else if(angle >=pi && angle <= 2*pi) return 23;
      else return 0;
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Determine the orientation of the polar labels according to their angle.
 
Double_t TSpider::FindTextAngle(Double_t angle)
{
   Double_t pi = TMath::Pi();
   Double_t convraddeg = 180.0/pi;
 
   while(angle < 0 || angle > 2*pi){
      if(angle < 0) angle+=2*pi;
      if(angle > 2*pi) angle-=2*pi;
   }
 
   if(angle >= 0 && angle <= pi/2) return angle*convraddeg - 90;
   else if(angle > pi/2 && angle <= pi) return (angle + pi)*convraddeg + 90;
   else if(angle > pi && angle <= 3*pi/2) return (angle - pi)*convraddeg - 90;
   else if(angle > 3*pi/2 && angle <= 2*pi) return angle*convraddeg + 90;
   else return 0;
}
 
////////////////////////////////////////////////////////////////////////////////
/// return the number of entries to be processed
/// this function checks that nentries is not bigger than the number
/// of entries in the Tree or in the associated TEventlist
 
Long64_t TSpider::GetEntriesToProcess(Long64_t firstentry, Long64_t nentries) const
{
   Long64_t lastentry = firstentry + nentries - 1;
   if (lastentry > fTree->GetEntriesFriend()-1) {
      lastentry  = fTree->GetEntriesFriend() - 1;
      nentries   = lastentry - firstentry + 1;
   }
   //TEventList *elist = fTree->GetEventList();
   //if (elist && elist->GetN() < nentries) nentries = elist->GetN();
   TEntryList *elist = fTree->GetEntryList();
   if (elist && elist->GetN() < nentries) nentries = elist->GetN();
   return nentries;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Go to a specified entry.
 
void TSpider::GotoEntry(Long64_t e)
{
   if(e<fFirstEntry || e+fTree->GetScanField()>=fFirstEntry + fNentries) return;
   fEntry = e;
   SetCurrentEntries();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Go to the next entries.
 
void TSpider::GotoNext()
{
   if(fEntry + 2*fTree->GetScanField() -1 >= fFirstEntry + fNentries) fEntry = fFirstEntry;
   else fEntry=fCurrentEntries[fTree->GetScanField()-1]+1;
   SetCurrentEntries();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Go to the previous entries.
 
void TSpider::GotoPrevious()
{
   if(fEntry-fTree->GetScanField() < fFirstEntry) fEntry = fFirstEntry + fNentries -1 - fTree->GetScanField();
   else fEntry -= fTree->GetScanField();
   SetCurrentEntries();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Go to the next entry.
 
void TSpider::GotoFollowing()
{
   if(fEntry + fTree->GetScanField() >= fFirstEntry + fNentries) return;
   ++fEntry;
   SetCurrentEntries();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Go to the last entry.
 
void TSpider::GotoPreceding()
{
   if(fEntry - 1 < fFirstEntry) return;
   --fEntry;
   SetCurrentEntries();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Check if the arrays size is enough and reallocate them if not.
 
void TSpider::InitArrays(Int_t newsize)
{
   if(newsize>fArraySize){
 
      Int_t i;
      Int_t old = fArraySize;
 
      while(fArraySize<newsize) fArraySize*=2;
 
      Double_t *memmax = new Double_t[fArraySize];
      Double_t *memmin = new Double_t[fArraySize];
      Double_t *memave = new Double_t[fArraySize];
 
      for(i=0;i<fArraySize;++i){
         if(i<old){
            memmax[i] = fMax[i];
            memmin[i] = fMin[i];
            memave[i] = fAve[i];
         } else {
            memmax[i] = -DBL_MAX;
            memmin[i] = DBL_MAX;
            memave[i] = 0;
         }
      }
 
      delete [] fMax;
      delete [] fMin;
      delete [] fAve;
 
      fMax = memmax;
      fMin = memmin;
      fAve = memave;
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Browse the tree to set the min, max and average value of each variable of fVar.
 
void TSpider::InitVariables(Long64_t firstentry, Long64_t nentries)
{
   UInt_t ui=0;
   Int_t i;
 
   fMax = new Double_t [fArraySize];
   fMin= new Double_t [fArraySize];
   fAve= new Double_t [fArraySize];
 
   for(i=0;i<fArraySize;++i){
      fMax[i]= -DBL_MAX;
      fMin[i]= DBL_MAX;
      fAve[i]=0;
   }
 
   Long64_t notSkipped=0;
   Int_t tnumber=-1;
   Long64_t entryNumber;
   Long64_t entry = firstentry;
   Int_t entriesToDisplay = nentries;
   while(entriesToDisplay!=0){
      entryNumber = fTree->GetEntryNumber(entry);
      if(entryNumber < 0) break;
      Long64_t localEntry = fTree->LoadTree(entryNumber);
      if(localEntry < 0) break;
      if(tnumber != fTree->GetTreeNumber()) {
         tnumber = fTree->GetTreeNumber();
         if(fManager) fManager->UpdateFormulaLeaves();
         else {
            for(i=0;i<=fFormulas->LastIndex();++i)
               ((TTreeFormula*)fFormulas->At(i))->UpdateFormulaLeaves();
         }
      }
      Int_t ndata=1;
      if(fForceDim){
         if(fManager)
            ndata = fManager->GetNdata(true);
         else {
            for(ui=0;ui<fNcols;++ui){
               if(ndata<((TTreeFormula*)fFormulas->At(ui))->GetNdata())
                  ndata = ((TTreeFormula*)fFormulas->At(ui))->GetNdata();
            }
            if(fSelect && fSelect->GetNdata() == 0)
               ndata = 0;
         }
      }
      bool loaded = false;
      bool skip = false;
      // Loop over the instances of the selection condition
      for(Int_t inst=0;inst<ndata;++inst){
         if(fSelect){
            if(fSelect->EvalInstance(inst) == 0){
               skip = true;
               ++entry;
            }
         }
         if (!loaded) {
            // EvalInstance(0) always needs to be called so that
            // the proper branches are loaded.
            for (ui=0;ui<fNcols;ui++) {
               ((TTreeFormula*)fFormulas->At(ui))->EvalInstance(0);
            }
            loaded = true;
         } else if (inst == 0) {
            loaded = true;
         }
      }
      if(!skip){
         fTree->LoadTree(entryNumber);
         for(ui=0;ui<fNcols;++ui){
            Double_t inst = ((TTreeFormula*)fFormulas->At(ui))->EvalInstance();
            if(inst > fMax[ui]) fMax[ui] = inst;
            if(inst < fMin[ui]) fMin[ui] = inst;
            fAve[ui] += inst;
         }
         ++notSkipped;
         --entriesToDisplay;
         ++entry;
      }
   }
   if (notSkipped) {for(ui=0;ui<fNcols;++ui) fAve[ui]/=notSkipped;}
}
 
////////////////////////////////////////////////////////////////////////////////
/// Paint the spider.
 
void TSpider::Paint(Option_t* options)
{
   UInt_t ui=0;
   TString opt = options;
 
   if(opt.Contains("n")) return;
 
   Double_t slice = 2*TMath::Pi()/fNcols;
   Double_t offset(1.0);
   if (!fCanvas) {
      if (gPad) fCanvas = gPad->GetCanvas();
      else return;
   }
 
   TLatex *txt = new TLatex();
   for(ui=0;ui<fNx*fNy;++ui){
      txt->SetTextAlign(13);
      if (fCanvas) fCanvas->cd(ui+1);
      if (fCurrentEntries) {
         txt->PaintLatex(-1.2,1.2,0,0.08,Form("#%d",(int)fCurrentEntries[ui]));
      }
      txt->SetTextSize(0.035);
      for(UInt_t var=0;var<fNcols;++var){ // Print labels.
         if(ui==0){
            txt->SetTextAlign(FindTextAlign(var*slice));
            offset = 1.09 + txt->GetTextSize();
            txt->PaintLatex(offset*TMath::Cos(var*slice),offset*TMath::Sin(var*slice),
                            FindTextAngle(var*slice),0.035,fFormulas->At(var)->GetTitle());
            offset= 1.03;
            txt->PaintLatex(offset*TMath::Cos(var*slice),offset*TMath::Sin(var*slice),
                            FindTextAngle(var*slice),0.035,Form("[%5.3f,%5.3f]",fMin[var],fMax[var]));
         }
         else {
            txt->SetTextAlign(FindTextAlign(var*slice));
            if(var*slice >=0 && var*slice <= TMath::Pi()) offset =1.13 + txt->GetTextSize();
            else offset = 1.09 + txt->GetTextSize();
            txt->PaintLatex(offset*TMath::Cos(var*slice),offset*TMath::Sin(var*slice),
                            FindTextAngle(var*slice),0.035,fFormulas->At(var)->GetTitle());
         }
      }
   }
   delete txt;
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set the LineStyle of the average.
 
void TSpider::SetAverageLineStyle(Style_t sty)
{
   UInt_t ui=0;
 
   if(fAverageSlices){
      for(ui=0;ui<fNcols;++ui) fAverageSlices[ui]->SetLineStyle(sty);
   } else if(fAveragePoly) fAveragePoly->SetLineStyle(sty);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set the LineColor of the average.
 
void TSpider::SetAverageLineColor(Color_t col)
{
   UInt_t ui=0;
 
   if(fAverageSlices){
      for(ui=0;ui<fNcols;++ui) fAverageSlices[ui]->SetLineColor(col);
   } else if(fAveragePoly) fAveragePoly->SetLineColor(col);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set the LineWidth of the average.
 
void TSpider::SetAverageLineWidth(Width_t wid)
{
   UInt_t ui=0;
 
   if(fAverageSlices){
      for(ui=0;ui<fNcols;++ui) fAverageSlices[ui]->SetLineWidth(wid);
   } else if(fAveragePoly) fAveragePoly->SetLineWidth(wid);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set the Fill Color of the average.
 
void TSpider::SetAverageFillColor(Color_t col)
{
   UInt_t ui=0;
 
   if(fAverageSlices){
      for(ui=0;ui<fNcols;++ui) fAverageSlices[ui]->SetFillColor(col);
   } else if(fAveragePoly) fAveragePoly->SetFillColor(col);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set the FillStyle of the average.
 
void TSpider::SetAverageFillStyle(Style_t sty)
{
   UInt_t ui=0;
 
   if(fAverageSlices){
      for(ui=0;ui<fNcols;++ui) fAverageSlices[ui]->SetFillStyle(sty);
   } else if(fAveragePoly) fAveragePoly->SetFillStyle(sty);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Display or not the average.
 
void TSpider::SetDisplayAverage(bool disp)
{
   if(disp == fDisplayAverage) return;
 
   UInt_t ui=0;
 
   fDisplayAverage = disp;
   delete fAveragePoly;
   fAveragePoly = nullptr;
   if(fAverageSlices){
      for(ui = 0;ui<fNcols;++ui) delete fAverageSlices[ui];
   }
   delete [] fAverageSlices;
   fAverageSlices = nullptr;
 
   for(ui=0;ui<fNx*fNy;++ui){
      if (fCanvas) fCanvas->cd(ui+1);
      gPad->Clear();
   }
 
   for(ui = 0; ui < fNx*fNy; ++ui){
      if (fCanvas) fCanvas->cd(ui+1);
      fPolargram->Draw("pn");
      fTree->LoadTree(fCurrentEntries[ui]);
      if(fSegmentDisplay){
         if(disp) DrawSlicesAverage("");
         DrawSlices("");
      } else {
         if(disp) DrawPolyAverage("");
         DrawPoly("");
      }
      AppendPad();
   }
   if (fCanvas) {
      fCanvas->Modified();
      fCanvas->Update();
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set the current selected entries.
 
void TSpider::SetCurrentEntries()
{
   Int_t i;
   UInt_t ui=0;
   Int_t tnumber=-1;
   Long64_t entryNumber;
   Long64_t entry = fEntry;
   Int_t entriesToDisplay = fTree->GetScanField();
 
   if(!fCurrentEntries) fCurrentEntries = new Long64_t[fTree->GetScanField()];
 
   while(entriesToDisplay!=0){
      entryNumber = fTree->GetEntryNumber(entry);
      if(entryNumber < 0) break;
      Long64_t localEntry = fTree->LoadTree(entryNumber);
      if(localEntry < 0) break;
      if(tnumber != fTree->GetTreeNumber()) {
         tnumber = fTree->GetTreeNumber();
         if(fManager) fManager->UpdateFormulaLeaves();
         else {
            for(i=0;i<=fFormulas->LastIndex();++i)
               ((TTreeFormula*)fFormulas->At(i))->UpdateFormulaLeaves();
         }
      }
      Int_t ndata=1;
      if(fForceDim){
         if(fManager)
            ndata = fManager->GetNdata(true);
         else {
            for(ui=0;ui<fNcols;++ui){
               if(ndata < ((TTreeFormula*)fFormulas->At(ui))->GetNdata())
                  ndata = ((TTreeFormula*)fFormulas->At(ui))->GetNdata();
            }
            if(fSelect && fSelect->GetNdata() == 0)
               ndata = 0;
         }
      }
      bool loaded = false;
      bool skip = false;
      // Loop over the instances of the selection condition
      for(Int_t inst=0;inst<ndata;++inst){
         if(fSelect){
            if(fSelect->EvalInstance(inst) == 0){
               skip = true;
               ++entry;
            }
         }
         if (!loaded) {
            // EvalInstance(0) always needs to be called so that
            // the proper branches are loaded.
            for (ui=0;ui<fNcols;ui++) {
               ((TTreeFormula*)fFormulas->At(ui))->EvalInstance(0);
            }
            loaded = true;
         } else if (inst == 0) {
            loaded = true;
         }
      }
      if(!skip){
          fCurrentEntries[fTree->GetScanField()-entriesToDisplay] = entryNumber;
         --entriesToDisplay;
         ++entry;
      }
   }
   if(fPolyList) UpdateView();
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set line style.
 
void TSpider::SetLineStyle(Style_t sty)
{
   UInt_t ui=0;
 
   TAttLine::SetLineStyle(sty);
   for(ui=0; ui<fNx*fNy;++ui){
      if(fSegmentDisplay){
         TList *li = (TList*)fPolyList->At(ui);
         for(UInt_t var=0;var<fNcols;++var) ((TArc*)li->At(var))->SetLineStyle(sty);
      } else ((TPolyLine*)fPolyList->At(ui))->SetLineStyle(sty);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set lin color.
 
void TSpider::SetLineColor(Color_t col)
{
   UInt_t ui=0;
 
   TAttLine::SetLineColor(col);
   for(ui=0; ui<fNx*fNy;++ui){
      if(fSegmentDisplay){
         TList *li = (TList*)fPolyList->At(ui);
         for(UInt_t var=0;var<fNcols;++var) ((TArc*)li->At(var))->SetLineColor(col);
      } else ((TPolyLine*)fPolyList->At(ui))->SetLineColor(col);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
///Set line width.
 
void TSpider::SetLineWidth(Width_t wid)
{
   UInt_t ui=0;
 
   TAttLine::SetLineWidth(wid);
   for(ui=0; ui<fNx*fNy;++ui){
      if(fSegmentDisplay){
         TList *li = (TList*)fPolyList->At(ui);
         for(UInt_t var=0;var<fNcols;++var) ((TArc*)li->At(var))->SetLineWidth(wid);
      } else ((TPolyLine*)fPolyList->At(ui))->SetLineWidth(wid);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set fill color.
 
void TSpider::SetFillColor(Color_t col)
{
   UInt_t ui=0;
 
   TAttFill::SetFillColor(col);
   for(ui=0; ui<fNx*fNy;++ui){
      if(fSegmentDisplay){
         TList *li = (TList*)fPolyList->At(ui);
         for(UInt_t var=0;var<fNcols;++var) ((TArc*)li->At(var))->SetFillColor(col);
      } else ((TPolyLine*)fPolyList->At(ui))->SetFillColor(col);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set fill style.
 
void TSpider::SetFillStyle(Style_t sty)
{
   UInt_t ui=0;
 
   TAttFill::SetFillStyle(sty);
   for(ui=0; ui<fNx*fNy;++ui){
      if(fSegmentDisplay){
         TList *li = (TList*)fPolyList->At(ui);
         for(UInt_t var=0;var<fNcols;++var) ((TArc*)li->At(var))->SetFillStyle(sty);
      } else ((TPolyLine*)fPolyList->At(ui))->SetFillStyle(sty);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set number of radial divisions.
 
void TSpider::SetNdivRadial(Int_t ndiv)
{
   if(fPolargram->GetNdivRadial() == ndiv) return;
   fPolargram->SetNdivRadial(ndiv);
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set the X number of sub pads.
 
void TSpider::SetNx(UInt_t nx)
{
   if(fNx == nx || nx <= 0) return;
   fEntry = fCurrentEntries[0];
 
   UInt_t ui=0;
   Color_t lc;
   Style_t lt;
   Width_t lw;
   Color_t fc;
   Style_t fs;
   if(fAverageSlices){
      lc = fAverageSlices[0]->GetLineColor();
      lt = fAverageSlices[0]->GetLineStyle();
      lw = fAverageSlices[0]->GetLineWidth();
      fc = fAverageSlices[0]->GetFillColor();
      fs = fAverageSlices[0]->GetFillStyle();
   } else {
      lc = fAveragePoly->GetLineColor();
      lt = fAveragePoly->GetLineStyle();
      lw = fAveragePoly->GetLineWidth();
      fc = fAveragePoly->GetFillColor();
      fs = fAveragePoly->GetFillStyle();
   }
 
   if(fSegmentDisplay){
      for(ui=0; ui<fNx*fNy;++ui) ((TList*)fPolyList->At(ui))->Delete();
   }
   fPolyList->Delete();
   delete fPolyList;
   fPolyList = nullptr;
   delete [] fCurrentEntries;
   fCurrentEntries = nullptr;
 
   fNx = nx;
 
   fTree->SetScanField(fNx*fNy);
   SetCurrentEntries();
   if (fCanvas) {
      fCanvas->Clear();
      fCanvas->Divide(fNx,fNy);
   }
 
   for(ui=0; ui < fNx*fNy;++ui){
      if (fCanvas) fCanvas->cd(ui+1);
      fPolargram->Draw("pn");
      fTree->LoadTree(fCurrentEntries[ui]);
      if(fSegmentDisplay){
         if(fDisplayAverage) DrawSlicesAverage("");
         DrawSlices("");
      } else {
         if(fDisplayAverage) DrawPolyAverage("");
         DrawPoly("");
      }
      AppendPad();
   }
 
   if(fAverageSlices){
      for(ui = 0;ui<fNcols;++ui){
         fAverageSlices[ui]->SetLineColor(lc);
         fAverageSlices[ui]->SetLineStyle(lt);
         fAverageSlices[ui]->SetLineWidth(lw);
         fAverageSlices[ui]->SetFillColor(fc);
         fAverageSlices[ui]->SetFillStyle(fs);
      }
   } else {
      fAveragePoly->SetLineColor(lc);
      fAveragePoly->SetLineStyle(lt);
      fAveragePoly->SetLineWidth(lw);
      fAveragePoly->SetFillColor(fc);
      fAveragePoly->SetFillStyle(fs);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set the Y number of sub pads.
 
void TSpider::SetNy(UInt_t ny)
{
   if(fNy == ny || ny <= 0) return;
   fEntry = fCurrentEntries[0];
 
   UInt_t ui=0;
   Color_t lc;
   Style_t lt;
   Width_t lw;
   Color_t fc;
   Style_t fs;
   if(fAverageSlices){
      lc = fAverageSlices[0]->GetLineColor();
      lt = fAverageSlices[0]->GetLineStyle();
      lw = fAverageSlices[0]->GetLineWidth();
      fc = fAverageSlices[0]->GetFillColor();
      fs = fAverageSlices[0]->GetFillStyle();
   } else {
      lc = fAveragePoly->GetLineColor();
      lt = fAveragePoly->GetLineStyle();
      lw = fAveragePoly->GetLineWidth();
      fc = fAveragePoly->GetFillColor();
      fs = fAveragePoly->GetFillStyle();
   }
 
   if(fSegmentDisplay){
      for(ui=0; ui<fNx*fNy;++ui) ((TList*)fPolyList->At(ui))->Delete();
   }
   fPolyList->Delete();
   delete fPolyList;
   fPolyList = nullptr;
   delete [] fCurrentEntries;
   fCurrentEntries = nullptr;
 
   fNy = ny;
 
   fTree->SetScanField(fNx*fNy);
   SetCurrentEntries();
   if (fCanvas) {
      fCanvas->Clear();
      fCanvas->Divide(fNx,fNy);
   }
 
   for(ui=0; ui < fNx*fNy;++ui){
      if (fCanvas) fCanvas->cd(ui+1);
      fPolargram->Draw("pn");
      fTree->LoadTree(fCurrentEntries[ui]);
      if(fSegmentDisplay){
         if(fDisplayAverage) DrawSlicesAverage("");
         DrawSlices("");
      } else {
         if(fDisplayAverage) DrawPolyAverage("");
         DrawPoly("");
      }
      AppendPad();
   }
 
   if(fAverageSlices){
      for(ui = 0;ui<fNcols;++ui){
         fAverageSlices[ui]->SetLineColor(lc);
         fAverageSlices[ui]->SetLineStyle(lt);
         fAverageSlices[ui]->SetLineWidth(lw);
         fAverageSlices[ui]->SetFillColor(fc);
         fAverageSlices[ui]->SetFillStyle(fs);
      }
   } else {
      fAveragePoly->SetLineColor(lc);
      fAveragePoly->SetLineStyle(lt);
      fAveragePoly->SetLineWidth(lw);
      fAveragePoly->SetFillColor(fc);
      fAveragePoly->SetFillStyle(fs);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Set the segment display or not.
 
void TSpider::SetSegmentDisplay(bool seg)
{
   if(seg == fSegmentDisplay) return;
 
   UInt_t ui=0;
 
   if(fSegmentDisplay){
      for(ui=0;ui<fNx*fNy;++ui){
         ((TList*)fPolyList->At(ui))->Delete();
      }
   }
   fPolyList->Delete();
 
   Color_t lc = 1;
   Style_t lt = 1;
   Width_t lw = 1;
   Color_t fc = 1;
   Style_t fs = 0;
   if(fAverageSlices){
      lc = fAverageSlices[0]->GetLineColor();
      lt = fAverageSlices[0]->GetLineStyle();
      lw = fAverageSlices[0]->GetLineWidth();
      fc = fAverageSlices[0]->GetFillColor();
      fs = fAverageSlices[0]->GetFillStyle();
   } else {
      if (fAveragePoly) {
         lc = fAveragePoly->GetLineColor();
         lt = fAveragePoly->GetLineStyle();
         lw = fAveragePoly->GetLineWidth();
         fc = fAveragePoly->GetFillColor();
         fs = fAveragePoly->GetFillStyle();
      }
   }
 
   delete fPolyList;
   fPolyList = nullptr;
   if(fAverageSlices){
      for(ui=0;ui<fNcols;++ui) delete fAverageSlices[ui];
   }
   delete [] fAverageSlices;
   fAverageSlices = nullptr;
   delete fAveragePoly;
   fAveragePoly = nullptr;
 
   for(ui=0;ui<fNx*fNy;++ui){
      if (fCanvas) fCanvas->cd(ui+1);
      gPad->Clear();
   }
 
   fSegmentDisplay = seg;
 
   for(ui=0; ui < fNx*fNy;++ui){
      if (fCanvas) fCanvas->cd(ui+1);
      fPolargram->Draw("pn");
      fTree->LoadTree(fCurrentEntries[ui]);
      if(fSegmentDisplay){
         if(fDisplayAverage) DrawSlicesAverage("");
         DrawSlices("");
      } else {
         if(fDisplayAverage) DrawPolyAverage("");
         DrawPoly("");
      }
      AppendPad();
   }
 
   if(fAverageSlices){
      for(ui=0;ui<fNcols;++ui){
         fAverageSlices[ui]->SetLineColor(lc);
         fAverageSlices[ui]->SetLineStyle(lt);
         fAverageSlices[ui]->SetLineWidth(lw);
         fAverageSlices[ui]->SetFillColor(fc);
         fAverageSlices[ui]->SetFillStyle(fs);
      }
   } else {
      if (fAveragePoly) {
        fAveragePoly->SetLineColor(lc);
        fAveragePoly->SetLineStyle(lt);
        fAveragePoly->SetLineWidth(lw);
        fAveragePoly->SetFillColor(fc);
        fAveragePoly->SetFillStyle(fs);
     }
   }
   if (fCanvas) {
      fCanvas->Modified();
      fCanvas->Update();
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Compile selection expression if there is one.
 
void TSpider::SetSelectionExpression(const char* selection)
{
   if (selection && strlen(selection)) {
      fSelect = new TTreeFormula("Selection",selection,fTree);
   //         if (!fSelect) return -1;
   //         if (!fSelect->GetNdim()) { delete fSelect; return -1; }
      fFormulas->Add(fSelect);
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Compile the variables expression from the given string varexp.
 
void TSpider::SetVariablesExpression(const char* varexp)
{
   Int_t nch;
   fNcols=8;
 
   if (!varexp) return;
   TObjArray *leaves = fTree->GetListOfLeaves();
   UInt_t nleaves = leaves->GetEntriesFast();
   if (nleaves < fNcols) fNcols = nleaves;
   nch = strlen(varexp);
 
   // if varexp is empty, take first 8 columns by default
   Int_t allvar = 0;
   std::vector<TString> cnames;
   if (!strcmp(varexp, "*")) { fNcols = nleaves; allvar = 1; }
   if (nch == 0 || allvar) {
      UInt_t ncs = fNcols;
      fNcols = 0;
      for (UInt_t ui=0;ui<ncs;++ui) {
         TLeaf *lf = (TLeaf*)leaves->At(ui);
         if (lf->GetBranch()->GetListOfBranches()->GetEntries() > 0) continue;
         cnames.push_back(lf->GetName());
         fNcols++;
      }
      // otherwise select only the specified columns
   } else {
      fNcols = fSelector->SplitNames(varexp,cnames);
   }
 
   // Create the TreeFormula objects corresponding to each column
   for (UInt_t ui=0;ui<fNcols;ui++) {
      fFormulas->Add(new TTreeFormula("Var1",cnames[ui].Data(),fTree));
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Create a TreeFormulaManager to coordinate the formulas.
 
void TSpider::SyncFormulas()
{
   Int_t i;
   if (fFormulas->LastIndex()>=0) {
      if (fSelect) {
         if (fSelect->GetManager()->GetMultiplicity() > 0 ) {
            if(!fManager) fManager = new TTreeFormulaManager;
            for(i=0;i<=fFormulas->LastIndex();i++) {
               fManager->Add((TTreeFormula*)fFormulas->At(i));
            }
            fManager->Sync();
         }
      }
      for(i=0;i<=fFormulas->LastIndex();i++) {
         TTreeFormula *form = ((TTreeFormula*)fFormulas->At(i));
         switch( form->GetManager()->GetMultiplicity() ) {
            case  1:
            case  2:
            case -1:
               fForceDim = true;
               break;
            case  0:
               break;
         }
 
      }
   }
}
 
////////////////////////////////////////////////////////////////////////////////
/// Update the polylines or the arcs for the current entries.
 
void TSpider::UpdateView()
{
   Double_t slice = 2*TMath::Pi()/fNcols;
 
   Double_t x,y,r;
 
   for(UInt_t pad=1;pad <= fNx*fNy;++pad){
      fTree->LoadTree(fCurrentEntries[pad-1]);
      for(UInt_t i=0;i<fNcols;++i){
         r = (((TTreeFormula*)fFormulas->At(i))->EvalInstance()-fMin[i])/(fMax[i]-fMin[i]);
         x=r*TMath::Cos(i*slice);
         y=r*TMath::Sin(i*slice);
         if(!fSegmentDisplay) ((TPolyLine*)fPolyList->At(pad-1))->SetPoint(i,x,y);
         else {
            ((TArc*)((TList*)fPolyList->At(pad-1))->At(i))->SetR1(r);
            ((TArc*)((TList*)fPolyList->At(pad-1))->At(i))->SetR2(r);
         }
      }
      x=(((TTreeFormula*)fFormulas->At(0))->EvalInstance()-fMin[0])/(fMax[0]-fMin[0]);
      y=0;
      if(!fSegmentDisplay) ((TPolyLine*)fPolyList->At(pad-1))->SetPoint(fNcols,x,y);
   }
}