Grep ignore case

1. By default, grep is case-sensitive (use -i to ignore case).
2. By default, grep ignores the context of a string (use -w to match words only).
3. By default, grep shows the lines that match (use -v to show those that don't match).

TVector3 is very useful when calculating the distance

TVector3 coreTankVec   = stationPos - showerCore ;
    TVector3 distanceVector=coreTankVec.Cross(showerAxis);
    test_distance=distanceVector.Mag();

Two Important indications about shower primaries

Xmax:
As a shower induced by an heavy nuclei develops earlier and faster, the expected value of Xmax is smaller than in the case of a proton.

Muonic Fraction:
The muonic fraction is expected to be larger in the case of an heavy nuclei.

缩写

WCD water cherenkov detectors
FADC Flash Analog-to-Digital Converters

Research Focus

Get some thing proportional to muon/electron

Overflow and Underflow display in root

gStyle->SetOptStat(111111);

reference:
http://root.cern.ch/root/html/TStyle.html

but do not forget to include the library

#include "TStyle.h"

Combining ps files and pdf files

•  Ps files

To merge the files `slide1.ps', `slide2.ps', and `slide3.ps' into a new PostScript file, `slideshow.ps', type:

$ psmerge -oslideshow.ps slide1.ps slide2.ps slide3.ps

to install psmerge, in ubuntu type:

 $ sudo apt-get install psutils

• Pdf files 

First of all you will need the program called pdftk. You can get it by opening terminal and typing:

$ sudo apt-get install pdftk

Now you can merge pdf files by putting them in the same directory and typing:

$ pdftk 1.pdf 2.pdf 3.pdf cat output merged.pdf

or if you wish to merge files in alphabetical order you can simply type:

$ pdftk *.pdf cat output merged.pdf

Make Scatter Plot, TGraph is better than TH2F

TGraph *gr1 = new TGraph(10);
   gr1->SetFillColor(6);
   gr1->SetFillStyle(3005);
   gr1->SetLineColor(6);
   gr1->SetLineWidth(603);
   gr1->SetPoint(0,140,0.5);
   gr1->SetPoint(1,130,2.9);
   gr1->SetPoint(2,124.677,3.83726);
   gr1->SetPoint(3,113.362,6.06903);
   gr1->SetPoint(4,108.513,8.00221);
   gr1->SetPoint(5,111.746,10.0272);
   gr1->SetPoint(6,119.828,12.8419);
   gr1->SetPoint(7,135.991,30.0872);
   gr1->SetPoint(8,140,40);
   gr1->SetPoint(9,135,60);
   gr1->Draw("C");
   TLatex *tex = new TLatex(140.841,37.9762,
      "#leftarrow t #rightarrow bH^{+}, H^{+} #rightarrow #tau#nu");
   tex->SetTextColor(6);
   tex->Draw();

Use FindRoot in Mathematica

Sometimes Solve or NSolve in Mathematica does not work in Complicated
Equations, for this case, FindRoot is a good tool.

http://reference.wolfram.com/mathematica/ref/FindRoot.html

Set X axis label

TH1I* particleDistr= new TH1I("particleDistr", "", 13, 1, 14);
  particleDistr->GetXaxis()->SetLabelSize(0.08);
 
  particleDistr->GetXaxis()->SetBinLabel(1,"#gamma");
  particleDistr->GetXaxis()->SetBinLabel(2,"e^{+}");
  particleDistr->GetXaxis()->SetBinLabel(3,"e^{-}");
  particleDistr->GetXaxis()->SetBinLabel(4,"#mu^{+}");
  particleDistr->GetXaxis()->SetBinLabel(5,"#mu^{-}");
  particleDistr->GetXaxis()->SetBinLabel(6,"#tau^{+}");
  particleDistr->GetXaxis()->SetBinLabel(7,"#tau^{-}");
  particleDistr->GetXaxis()->SetBinLabel(8,"#pi^{0}");
  particleDistr->GetXaxis()->SetBinLabel(9,"#pi^{+}");
  particleDistr->GetXaxis()->SetBinLabel(10,"#pi^{-}");
  particleDistr->GetXaxis()->SetBinLabel(11,"n");
  particleDistr->GetXaxis()->SetBinLabel(12,"p^{#pm}");
  particleDistr->GetXaxis()->SetBinLabel(13,"?");     
 
  fTracesObjects->Add(particleDistr);