{
//
// Get random numbers and show the correlations
// 

gROOT->Reset();

#include "myrand.h"

int number_of_points=20000;
int a=11679,c=32431,m=129029;

// create canvas
c1 = new TCanvas("c1","Distribution of Random Numbers",200,10,700,780);
c1->SetGrid();
c1->SetFillColor(42);
// pad for plot
pad1 = new TPad("pad1","Pad for 1d rand numbers",0.02,0.62,0.98,0.98,21);
pad2 = new TPad("pad2","Pad for 2d rand numbers",0.02,0.1,0.48,0.6,21);
pad3 = new TPad("pad3","Pad for 3d rand numbers",0.50,0.1,0.98,0.6,21);
pad4 = new TPad("pad4","Pad for Value output",0.02,0.02,0.98,0.08,21);
pad1->Draw();
pad2->Draw();
pad3->Draw();
pad4->Draw();
prand=new CMyRand();
prand->setseed(10);
prand->setpara(a,c,m);
pad4->cd();

char text[80];
sprintf(text,"a = %d  c = %d  m = %d",a,c,m);
rndtxt = new TText(0.1,0.1,text);
rndtxt->SetTextSize(0.8);
rndtxt->Draw();
pad1->cd();
pad1->SetGridx();
pad1->SetGridy();
// create 1d-Histo
h1f = new TH1F("h1f","Random Numbers",20,0.0,1.0);
h1f->SetMarkerStyle(21);
h1f->SetMarkerSize(0.7);
h1f->SetFillColor(2);
h1f->Draw();
for(int i=1;i<=number_of_points;++i)
{
  h1f->Fill(prand->getrand());
  if(i%1000 == 0) {
       h1f->Draw();
       c1->Modified();
       c1->Update();
  }
}
// check correlation between 2 random numbers
pad2->cd();
pad2->SetGridx();
pad2->SetGridy();
nt2d = new TNtuple("nt2d","2D Random numbers","r1:r2:i");
for(int i=1;i<=number_of_points;++i) 
{
  float x,y;
  x=prand->getrand();
  y=prand->getrand(); 
  nt2d->Fill(x,y,i);
}
// now draw the Ntuple entries
nt2d->SetMarkerStyle(20);
nt2d->SetMarkerSize(0.3);
nt2d->SetMarkerColor(5);
nt2d->Draw("r1:r2");
c1->Modified();
c1->Update();
// check correlation between 3 random numbers
// create NTuple with random numbers
pad3->cd();
nt3d = new TNtuple("nt3d","3D Random numbers","r1:r2:r3:i");
for(int i=1;i<=number_of_points;++i) 
{
  float x,y,z;
  x=prand->getrand();
  y=prand->getrand(); 
  z=prand->getrand(); 
  nt3d->Fill(x,y,z,i);
}
// now draw the Ntuple entries
nt3d->SetMarkerStyle(20);
nt3d->SetMarkerSize(0.3);
nt3d->SetMarkerColor(2);
nt3d->Draw("r1:r2:r3");
nt3d->Draw("r1:r2:r3","r3<1.0 && r3>=0.6","same");
nt3d->SetMarkerColor(4);
nt3d->Draw("r1:r2:r3","r3<0.3","same");
nt3d->SetMarkerColor(3);
nt3d->Draw("r1:r2:r3","r3<0.6 && r3>=0.3","same");
c1->Modified();
c1->Update();
};