rh2_large.cxx File Reference

Detailed Description

This macro generates really large RH2D histogram, fills it with predefined pattern and draw it in a RCanvas, using Optmize() drawing mode.

 
/*************************************************************************
 * Copyright (C) 1995-2020, 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 "ROOT/RHistDrawable.hxx"
#include "ROOT/RCanvas.hxx"
#include "ROOT/RFrameTitle.hxx"
#include "ROOT/RHistStatBox.hxx"
#include "ROOT/RFrame.hxx"
#include "TString.h"
 
// macro must be here while cling is not capable to load
// library automatically for outlined function see ROOT-10336
R__LOAD_LIBRARY(libROOTHistDraw)
 
using namespace ROOT::Experimental;
 
void rh2_large()
{
   const int nbins = 2000;
 
   // Create the histogram.
   RAxisConfig xaxis("x", nbins, 0., nbins);
   RAxisConfig yaxis("y", nbins, 0., nbins);
   auto pHist = std::make_shared<RH2D>(xaxis, yaxis);
 
   for(int i=0;i<nbins;++i)
      for(int j=0;j<nbins;++j)
         pHist->Fill({1.*i,1.*j}, i+j);
 
   // Create a canvas to be displayed.
   auto canvas = RCanvas::Create("Large 2000x2000 RH2 drawing");
 
   auto frame = canvas->AddFrame();
 
   // should we made special style for frame with palette?
   // frame->margins.right = 0.2_normal;
 
   frame->gridX = false;
   frame->gridY = false;
   frame->x.zoomMin = nbins*0.2;
   frame->x.zoomMax = nbins*0.8;
   frame->y.zoomMin = nbins*0.2;
   frame->y.zoomMax = nbins*0.8;
 
   canvas->Draw<RFrameTitle>(TString::Format("Large RH2D histogram with %d x %d bins",nbins,nbins).Data());
 
   auto draw = canvas->Draw(pHist);
 
   draw->line.color = RColor::kLime;
   // draw->Contour(); // configure cont draw option
   // draw->Scatter(); // configure scatter draw option
   // draw->Arrow(); // configure arrow draw option
   draw->Color(); // configure color draw option (default)
   // draw->Text(true); // configure text drawing (can be enabled with most 2d options)
   // draw->Box(1); // configure box1 draw option
   // draw->Surf(2); // configure surf4 draw option, 3d
   // draw->Lego(2); // configure lego2 draw option, 3d
   // draw->Error(); // configure error drawing, 3d
 
   draw->optimize = true; // enable draw optimization, reduced data set will be send to clients
 
   auto stat = canvas->Draw<RHist2StatBox>(pHist, "hist");
   stat->fill.color = RColor::kBlue;
   stat->fill.style = RAttrFill::kSolid;
 
   canvas->SetSize(1000, 700);
   canvas->Show();
}

Date

2020-06-26

Warning

This is part of the ROOT 7 prototype! It will change without notice. It might trigger earthquakes. Feedback is welcome!

Author

Sergey Linev s.lin.nosp@m.ev@g.nosp@m.si.de

Definition in file rh2_large.cxx.