static.doc

`Static' Analysis Mode

The C code in static.C plus the script run_static constitute a typical set of files to run in 'static' mode. The script run_static shows the full compilation+link sequence required to build a fully static executable.

The advantages of the "static" mode are:

The code is compiled, so execution is fast.

Since the executable is static, you can create it anywhere, copy it to any other Linux machine and execute it as it is (no need of any machine-specific libraries at run time).

It is an ideal mode for "batch" jobs, where the availability of the run-time libraries is not guaranteed at all.

To run tests on small files and many times, an interpreted mode, like CINT or Python are more convenient.

The price to pay for a static executable is its size (many Mbytes). If disk space is an issue, linking with shared libraries (used at run-time), like in the "dynamic" mode is preferred. There are also some "annmoying" features, like some warnings at compilation/link time.

The default ROOT versions are distributed only with "shared" libraries. This means that, in order to run in "static" mode, you'll need ROOT static librares installed. See README_install_Root for details.

The static ROOT library does not have "graphic support". Therefore, you can just process, analyze and create histograms in "static" mode, but not visualize them simultaneously (do it afterwards in an interactive ROOT session, for instance).

We can add several Root files with the AMSChain::Add("file") method. The AMSChain class inherits all the methods of the TChain class, but simplifies the life by hiding some AMS internal operations. Example:

AMSChain* ams = new AMSChain;
ams->Add("../files/test.root");
char chfile[256] = "rfio:my_castor_file.root";
new TRFIOFile(chfile);
ams->Add(chfile);

The analysis is performed on AMSEventR objects:

"AMSEventR* pev = ams.GetEvent()"

"AMSEventR* pev = ams.GetEvent(entry_number)"

"AMSEventR* pev = ams.GetEvent(run_number, event_number)"

If you prefer not to do pointer coding like "pev->whatever", you can add:

"AMSEventR &ev = *pev;"

and use "ev.whatever" from that point on.

In order to access in a simple way all relevant pieces of information many useful definitions, via pointers and vectors, are implemented. For example, the number of hits in ECAL is given by::

cout << "#Ehits: " << ev.nEcalHit() << endl;

or, alternatively:

cout << "#Ehits: " << pev->nEcalHit() << endl;

The "i" Hit in ECAL belongs to the class EcalHitR, and it may be accessed either as:

EcalHitR hit = ev.EcalHit(i);

or via the pointers:

EcalHitR* phit = pev->pEcalHit(i);

A reference to the ith element is obtained as:

EcalHitR* phit = &ev.EcalHit(i);

The full list of AMS classes and attributes can be found HERE . For instance, in EcalHitR the first member is "Status", which can be accessed either as:

int stat = ev.EcalHit(i).Status;

or:

int stat = pev->pEcalHit(i)->Status;

#!/bin/sh

file="static.C"
exe="static.exe"

# Use all libs
#all_libs=1
# Use just libAMSRoot
unset all_libs

AMSLIBS="../lib/libAMSRoot.a"
AMSINCS="-I../lib/AMSRoot"
if [ -n "$all_libs" ]; then
  old_dir=${PWD}
  cd ../lib
  for dir in `ls -d */` ; do
      dir=${dir/\//}
      if [ "${dir}" != "CVS" -a "${dir}" != "AMSRoot" ]; then
            AMSINCS="${AMSINCS} -I../lib/${dir}"
            AMSLIBS="${AMSLIBS} ../lib/lib${dir}.a"
      fi      
  done
  cd ${old_dir}
fi

if [ "`/usr/bin/gcc -dumpversion`" == "2.96" ]; then
  if [ -e "/usr/local/gcc-alt-3.2.3" ]; then
      export PATH=/usr/local/gcc-alt-3.2.3/bin:$PATH
  fi
fi

ROOTLIBDIR=`$ROOTSYS/bin/root-config --libdir`
ROOTINCDIR=`$ROOTSYS/bin/root-config --incdir`

system=`uname`
CXXOPTS="-Wno-deprecated"
if [ "$system" != "Darwin" ]; then
      CXXOPTS="-Wno-deprecated -static"
fi

machine=`uname -m`
if [ "$machine" = "x86_64" ]; then
      CXXOPTS="${CXXOPTS} -fPIC -m32"
fi

LIBS="${AMSLIBS} ${ROOTLIBDIR}/libRoot.a ${ROOTLIBDIR}/libpcre.a"

if [ "$system" != "Darwin" ]; then
      LIBS="${LIBS} -ldl"
fi

RFIO=`$ROOTSYS/bin/root-config --has-rfio`
if [ "$RFIO" = "yes" ]; then
      LIBS="${LIBS} -lshift"
fi

if [ -e "/usr/lib/ctype-info.o" ]; then
      RH9add="-pthread /usr/lib/ctype-info.o"
else
      RH9add=
fi

INCS="${AMSINCS} -I${ROOTINCDIR}"

echo -e "\n>>> Recreating libraries if necessary: ${AMSLIB}"
old_dir=$PWD
cd ../lib/ >/dev/null
make static
if [ -n "$all_libs" ]; then
      make utils_static
fi
cd $old_dir


echo -e "\n>>> COMPILING and LINKING: ${file}"
make -f - -s <<!
SHELL=/bin/sh
${exe}: ${file} ${AMSLIBS}
        g++ ${CXXOPTS} ${INCS} -o ${exe} ${file} ${LIBS} ${RH9add}
!

echo -e "\n>>> EXECUTING: ${exe}"
${exe}

#include <root.h>
#include "TFile.h"
#include "TH1F.h"
/* NEEDED FOR CASTOR FILES 
#include "TRFIOFile.h"
*/

int main(){

      AMSChain* ams = new AMSChain;
      ams->Add("../files/test.root");
      //ams->Add("http://pcamsf0.cern.ch/f2dah1/MC/AMS02/2004A/protons/el.pl1.10200/738197524.0000001.root");

      /* NEEDED FOR CASTOR FILES
      char chfile[256] = "rfio:/castor/cern.ch/ams/MC/AMS02/2004A/protons/el.pl1.10200/738197524.0000001.root";
      new TRFIOFile(chfile);
      ams->Add(chfile);
      */

      TFile* hfile = new TFile ("amstest.root", "RECREATE"); 

      AMSEventList* list = new AMSEventList;

      TH1F* hrig = new TH1F ("hrig", "Momentum (GeV)", 50, -10., 10.);
      
      AMSEventR* pev = NULL;
      while (pev = ams->GetEvent()) {
            if (pev==NULL) break;
            for (int i=0; i<pev->nParticle(); i++) {
                  ParticleR* part = pev->pParticle(i);
                  hrig->Fill(part->Momentum);
                  if (pev->nVertex()>0) {
                          list->Add(pev); // Add to list of selected events
                          pev->Fill(); // write it into output ROOT file
                  }
            }
      }

      //hrig->Draw();
      hfile->Write();
      list->Write("select.list");

      printf("We have processed %d events\n", (int)ams->GetEntries());
      printf("Histograms saved in '%s'\n", hfile->GetName());
}

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