1 / 23

Introduction of ROOT

Introduction of ROOT. Yao. ROOT Development. In the mid 1990's, René Brun and Fons Rademakers, they had lead successful projects such as PAW, PIAF, and GEANT .

hong
Download Presentation

Introduction of ROOT

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Introduction of ROOT Yao

  2. ROOT Development • In the mid 1990's, René Brun and Fons Rademakers, they had lead successful projects such as PAW, PIAF, and GEANT . • They knew the twenty-year-old FORTRAN libraries had reached their limits, could not scale up to the challenges offered by the Large Hadron Collider. • At the same time, computer science had made leaps of progress especially in the area of Object Oriented Design (OOD). What is ROOT ?

  3. Object-Oriented Design (OOD) • Modularity • Reusability • Extendibility • Maintenance • Etc…

  4. Smalltalk: Smalltalk-80 • C based : objective-C , C++ , JAVA , C# • LISP based : Flavors , XLISP , LOOPS,CLOS • PASCAL based : Object Pascal , Turbo Pascal, Eiffel, Ada 95

  5. CINT • CINT is a command line C/C++ interpreter. • The syntax is a bit more forgiving than either language. Interpreted languages : • BASIC , Lisp , Perl , Scheme , Python , Ruby , Tcl and Tk , Unix Shell , JavaScript , PHP , VBScript

  6. ROOT is an object-oriented framework aimed at solving the data analysis challenges of high-energy physics , • it provides a large selection of HEP specific utilities such as histograms and fitting. • 2D Graphics, 3D Graphics , etc. Why do we use ROOT ?

  7. histogram

  8. histograms and fitting

  9. 2D Graphics

  10. 3D Graphics

  11. Setting the Environment Variables [shyao@ipas012 ~] $ export SOFT="${HOME}/local" [shyao@ipas012 ~] $ export ROOTSYS="${SOFT}/root" [shyao@ipas012 ~] $ export PATH="${SOFT}/root/bin:${PATH}" [shyao@ipas012 ~] $ export LD_LIBRARY_PATH="${SOFT}/root/lib/root:${LD_LIBRARY_PATH}” ~/.bashrc Please note: the syntax is for bash. How to use ROOT ?

  12. Start and Quit a ROOT Session [shyao@ipas012 ~] $ root *************************************** * * * W E L C O M E to R O O T * * * * Version 5.27/02 26 April 2010 * * * * You are welcome to visit our Web site * * http://root.cern.ch * * * *************************************** ROOT 5.27/02 (trunk@33229, Apr 27 2010, 11:38:29 on linux) CINT/ROOT C/C++ Interpreter version 5.17.00, Dec 21, 2008 Type ? for help. Commands must be C++ statements. Enclose multiple statements between { }. root [0] .q [shyao@ipas012 ~] $

  13. help [shyao@ipas012 ~]$ root -? Usage: root [-l] [-b] [-n] [-q] [dir] [[file:]data.root] [file1.C ... fileN.C] Options: -b : run in batch mode without graphics -n : do not execute logon and logoff macros as specified in .rootrc -q : exit after processing command line macro files -l : do not show splash screen dir : if dir is a valid directory cd to it before executing

  14. command line root[0] 1+sqrt(9) (const double)4.00000000000000000e+00 root[1] for (int i = 0; i<4; i++) cout << "Hello " << i << endl Hello 0 Hello 1 Hello 2 Hello 3 root[2] .q

  15. histogram Do not need to include header file that root provide. void fith() {//filename double tmp; ifstream fin("./data/rr.txt"); int i=0; TCanvas *c1 = new TCanvas("c1","fitting Histogram",200,10,700,500); TH1D *h1 = new TH1D( "h1", "hist1", 20, 0, 10 ); while(!fin.eof()){ fin>>tmp; h1->Fill( tmp*1000000. ); } fin.close(); h1->SetTitle("muon lifetime"); h1->SetXTitle("10^{-6}s"); h1->SetYTitle("count"); //******** h1->Draw("E"); C1->Print(); }

  16. Run a script [shyao@ipas012 ]$ root fith.C or root [0] .x fith.C

  17. fitting TF1 *t1 = new TF1("t1","[0]+[1]*exp(-x/[2])",0,bin); t1->SetParNames("a","b","lifetime"); t1->SetParameter(0,6); t1->SetParLimits(0,0,10); t1->SetParameter(1,1); t1->SetParameter(2,2.2); h1->Fit("t1"); [shyao@ipas012 ]$ root fith.C NO. NAME VALUE ERROR SIZE DERIVATIVE 1 a 2.66609e+00 1.56321e+00 3.68519e-04 4.12958e-04 2 b 1.48634e+02 9.03901e+00 1.18599e-02 1.96484e-05 3 lifetime 2.26596e+00 1.82994e-01 1.49850e-04 1.42577e-03

  18. Scatter Diagram void graph() { TCanvas *c1 = new TCanvas("c1","A Simple Graph Example",200,10,700,500); const Int_t n = 20; Double_t x[n], y[n]; for (Int_t i=0;i<n;i++) { x[i] = i; y[i] = sin(i*0.5); } gr = new TGraph(n,x,y); //****** gr->Draw("AP*"); c1->Update(); c1->Modified(); }

  19. [shyao@ipas012 code]$ root graph.C

  20. gr->SetLineColor(2); gr->SetLineWidth(4); gr->SetMarkerColor(4); gr->SetMarkerStyle(21); gr->SetTitle("a simple graph"); gr->GetXaxis()->SetTitle("X title"); gr->GetYaxis()->SetTitle("Y title"); gr->Draw("ACP*");

  21. 2D Graphics void graph2d(){ TCanvas *c = new TCanvas("c","Graph2D example",0,0,700,600); Double_t x, y, z, P = 6.; Int_t np = 200; TGraph2D *dt = new TGraph2D(); TRandom *r = new TRandom(); for (Int_t N=0; N<np; N++) { x = 2*P*(r->Rndm(N))-P; y = 2*P*(r->Rndm(N))-P; z = (sin(x)/x)*(sin(y)/y)+0.2; dt->SetPoint(N,x,y,z); } gStyle->SetPalette(1); dt->Draw("surf1"); }

More Related