parallelcoordtrans.C File Reference

Detailed Description

Use of transparency with ||-Coord.

It displays the same data set twice. The first time without transparency and the second time with transparency. On the second plot, several clusters appear.

Images without and with transparency

#include "TFile.h"
#include "TCanvas.h"
#include "TStyle.h"
#include "TRandom.h"
#include "TNtuple.h"
#include "TParallelCoord.h"
#include "TParallelCoordVar.h"
#include "TParallelCoordRange.h"

Double_t r1,r2,r3,r4,r5,r6,r7,r8,r9;
Double_t dr = 3.5;
TRandom *r;

void generate_random(Int_t i) {
   r->Rannor(r1,r4);
   r->Rannor(r7,r9);
   r2 = (2*dr*r->Rndm(i))-dr;
   r3 = (2*dr*r->Rndm(i))-dr;
   r5 = (2*dr*r->Rndm(i))-dr;
   r6 = (2*dr*r->Rndm(i))-dr;
   r8 = (2*dr*r->Rndm(i))-dr;
}

void parallelcoordtrans() {
   Double_t x,y,z,u,v,w,a,b,c;
   Double_t s1x, s1y, s1z;
   Double_t s2x, s2y, s2z;
   Double_t s3x, s3y, s3z;
   r = new TRandom();;

   TCanvas *c1 = new TCanvas("c1", "c1",0,0,900,1000);
   c1->Divide(1,2);

   TNtuple *nt = new TNtuple("nt","Demo ntuple","x:y:z:u:v:w:a:b:c");

   int n=0;
   for (Int_t i=0; i<1500; i++) {
      r->Sphere(s1x, s1y, s1z, 0.1);
      r->Sphere(s2x, s2y, s2z, 0.2);
      r->Sphere(s3x, s3y, s3z, 0.05);

      generate_random(i);
      nt->Fill(r1, r2, r3, r4, r5, r6, r7, r8, r9);
      n++;

      generate_random(i);
      nt->Fill(s1x, s1y, s1z, s2x, s2y, s2z, r7, r8, r9);
      n++;

      generate_random(i);
      nt->Fill(r1, r2, r3, r4, r5, r6, r7, s3y, r9);
      n++;

      generate_random(i);
      nt->Fill(s2x-1, s2y-1, s2z, s1x+.5, s1y+.5, s1z+.5, r7, r8, r9);
      n++;

      generate_random(i);
      nt->Fill(r1, r2, r3, r4, r5, r6, r7, r8, r9);
      n++;

      generate_random(i);
      nt->Fill(s1x+1, s1y+1, s1z+1, s3x-2, s3y-2, s3z-2, r7, r8, r9);
      n++;

      generate_random(i);
      nt->Fill(r1, r2, r3, r4, r5, r6, s3x, r8, s3z );
      n++;
   }

   TParallelCoordVar* pcv;

   c1->cd(1);

   // ||-Coord plot without transparency
   nt->Draw("x:y:z:u:v:w:a:b:c","","para");
   TParallelCoord* para1 = (TParallelCoord*)gPad->GetListOfPrimitives()->FindObject("ParaCoord");
   para1->SetLineColor(25);
   pcv = (TParallelCoordVar*)para1->GetVarList()->FindObject("x"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para1->GetVarList()->FindObject("y"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para1->GetVarList()->FindObject("z"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para1->GetVarList()->FindObject("a"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para1->GetVarList()->FindObject("b"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para1->GetVarList()->FindObject("c"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para1->GetVarList()->FindObject("u"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para1->GetVarList()->FindObject("v"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para1->GetVarList()->FindObject("w"); pcv->SetHistogramHeight(0.);


   // ||-Coord plot with transparency
   TColor *col26 = gROOT->GetColor(26); col26->SetAlpha(0.01);
   c1->cd(2);
   nt->Draw("x:y:z:u:v:w:a:b:c","","para");
   TParallelCoord* para2 = (TParallelCoord*)gPad->GetListOfPrimitives()->FindObject("ParaCoord");
   para2->SetLineColor(26);
   pcv = (TParallelCoordVar*)para2->GetVarList()->FindObject("x"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para2->GetVarList()->FindObject("y"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para2->GetVarList()->FindObject("z"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para2->GetVarList()->FindObject("a"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para2->GetVarList()->FindObject("b"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para2->GetVarList()->FindObject("c"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para2->GetVarList()->FindObject("u"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para2->GetVarList()->FindObject("v"); pcv->SetHistogramHeight(0.);
   pcv = (TParallelCoordVar*)para2->GetVarList()->FindObject("w"); pcv->SetHistogramHeight(0.);

   // Produce transparent lines in interactive and batch mode
   c1->Print("parallelcoordtrans.pdf");
   c1->Print("parallelcoordtrans.svg");

   // Produce transparent lines in batch mode only
   c1->Print("parallelcoordtrans.gif");
   c1->Print("parallelcoordtrans.jpg");
   c1->Print("parallelcoordtrans.png");
}

Author

Olivier Couet

Definition in file parallelcoordtrans.C.