Hall A ROOT/analyzer installation HOWTO

This file is maintained by Seamus Riordan
riordan@jlab.org

Last Modified November 11, 2005

To get analyzer installed, you must first have ROOT installed.  
Assuming this is not done, the latest ROOT can be obtained from 
http://root.cern.ch/root/Availability.html in the form of precompiled 
binaries or source.  Once these are unpacked add the path to the top 
level ROOT directory to the environment variable ROOTSYS (for example, 
this is /apps/root/4.00-08/root on ifarml1), add $ROOTSYS/bin to PATH, 
and $ROOTSYS/lib to LD_LIBRARY_PATH.  If ROOT is already installed, 
this may or may not be already done.  Check to make sure these 
variables are correct, because ROOTSYS must be defined before installing analyzer.

Before using CVS set CVS_RSH to ssh.  The analyzer package can be 
checked out from the CVS depository using:

cvs -d :ext:username@cvs.jlab.org:/group/halla/analysis/cvs co -d myanalyzer analyzer

Where $ANALYZER is the directory where analyzer is installed.  
Once this is downloaded and the decoder is updated, go into the
 analyzer directory and (assuming you're putting this on Linux) 
run gmake and grab some coffee.  The top level directory analyzer 
(also now containing the program analzyer) should be added to the 
environment variable ANALYZER and then $ANALYZER to both your PATH 
and LD_LIBRARY_PATH.  Once all this is done, you should be able to 
execute analzyer from the command line.  Before running analzyer, 
you should set the DB_DIR environment variable to the directory 
containing the necessary databases for your analysis.

The agen package may be checked out from CVS by:

cvs -d :ext:username@cvs.jlab.org:/group/halla/analysis/cvs co -d myagenlib agen

Running make from the command line should now work.

The library libAGen.so generated by make can be accessed by adding 
the agen directory to LD_LIBRARY_PATH or, since it is a single library, 
it may be more convenient to load it on a case by case basis by 
gSystem->Load(<path>/libAGen.so) in ROOT/analyzer 
where <path> is the path in the directory structure.

Here is an example of what I have in my .login in my ifarml1 account (csh):

 setenv CVS_RSH ssh
 setenv ROOTSYS /apps/root/4.00-08/root
 setenv ANALYZER /work/halla/e02013/disk1/analyzer
 setenv PATH $PATH':'$ANALYZER':'$ROOTSYS/bin
 setenv LD_LIBRARY_PATH $ANALYZER':'$ROOTSYS/lib
 setenv DB_DIR /work/halla/e02013/disk1/db

and for a machine with a bash account in my .bashrc:

 export CVS_RSH=ssh
 export ROOTSYS=/home/riordan/root
 export ANALYZER=/home/riordan/analyzer
 export PATH=$PATH:$ROOTSYS/bin:$ANALYZER
 export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$ROOTSYS/lib:$ANALYZER
 export DB_DIR=/home/riordan/DB


The analzyer should now be ready to run.  However, one should keep in mind 
that the analyzer should not be run in the analyzer directory.  It is best 
to create a directory for this purpose, usually containing the scripts one 
wishes to run.  To execute a script you may go into that directory and from
the command line run:

analzyer <script>

You may also run analyzer by itself to work from the ROOT/C interpreter. 
To execute a script within the interpreter run:

.x <script>

or, if the script requires or takes arguments:

.x <script>+(args... )

where args is the standard comma delimited set of arguements. 
To exit the interpreter, simply use

.q

For more information on analyzer or ROOT in general:

Analyzer Quick Start Guide	     http://hallaweb.jlab.org/root/doc/quickstart.html
Hall A C++ Analyzer Documentation   http://hallaweb.jlab.org/root/doc/index.html
ROOT Documentation		        ftp://root.cern.ch/root/doc/Users_Guide_4_08.pdf

To obtain the latest version of the software after it has been checked out as above,
simply go into the directory with the package you wish to update and run:

cvs update

This will synch the copy of source you have with the copy in the CVS repository.  
This only updates the source, however, and you must run make again for the latest binaries.