[u/mrichter/AliRoot.git] / ITS / manual / itsmanch0.tex

\chapter*{Introduction}
\section*{Purpose of this document}

This document is intended to both explain who to use the ALICE simulation and
reconstruction code with respect to or using the ITS detector as the
examples. This document is also to explain how to add new code to the ITS
simulation and reconstruction library, and who the existing ITS simulation and
reconstruction code works. All comments from every user is greatly encouraged.

\section*{How to Run AliRoot}

At this point, we will assume that aliroot has been compiled and all the
necessary environment variables have been defined, including your path. We will
assume you are in an appropriate directory, for example \texttt{/data} or some
such thing.

to start with type, at your shell prompt, aliroot to start the program.

\begin{verbatim}
# aliroot
Constant Field Map1 created: map= 1, factor= 1.000000
  *******************************************
  *                                         *
  *        W E L C O M E  to  R O O T       *
  *                                         *
  *   Version   2.26/00  10 November 2000   *
  *                                         *
  *  You are welcome to visit our Web site  *
  *          http://root.cern.ch            *
  *                                         *
  *******************************************

FreeType Engine v1.x used to render TrueType fonts.
Compiled with thread support.

CINT/ROOT C/C++ Interpreter version 5.14.58, Oct 24 2000
Type ? for help. Commands must be C++ statements.
Enclose multiple statements between { }.

WELCOME to ALICE

root [0]
\end{verbatim}

This will initialize ROOT and load all of the ALICE libraries. At this point you
can do anything you can do in ROOT in addition you have access to every class
defined in the ALICE libraries, including the ALICE global variables. One very
useful ALICE global variable is \texttt{gAlice} which is of type
\texttt{AliRun}. Of the many function defined in the class \texttt{AliRun} are
\texttt{Init(const char* setup="Config.C")} and 
\texttt{Run(const char* setup="Config.C")}. \texttt{Run} both executes
\texttt{Init} and starts executing an ALICE detector simulation. Both of these
functions functions load and execute a configuration file. By default this
configuration file is called \texttt{Config.C}. If such a file exists in your
local directory, for example \texttt{/data}, or if there is no such file in
your local directory it will execute the file
\texttt{\$ALICE\_ROOT/macros/Config.C}. Some other configuration file can be
run simplely by entering that file's name as the argument, for example
\texttt{Init("MyConfig.C")} or \texttt{Run("MyConfig.C")} where
\texttt{MyConfig.C} is either in your local directory (\texttt{/data}) or in
\texttt{\$ALICE\_ROOT/macros}. Of course the full path of \texttt{MyConfig.C}
can be used.

Now lets assume you just want to one event using the standard \texttt{Config.C}
file. This is done simply as
\begin{verbatim}
root [0] gAlice->Run()
Warning in <AliRun::SetField>: Invalid magnetic field flag:  -999; Helix trackin
g chosen instead

Warning in <AliFRAMEv1::ReadEuclidMedia>: file: $(ALICE_ROOT)/Euclid/frame.tme i
s now read in

Warning in <AliPIPEv0::ReadEuclidMedia>: file: $(ALICE_ROOT)/Euclid/pipe.tme is 
now read in

Warning in <AliITSv5::ReadEuclidMedia>: file: /home/CERN/aliroot/dev/Euclid/ITSg
eometry_5.tme is now read in


 MZSTOR.  ZEBRA table base TAB(0) in /MZCC/ at adr   281557647    10C83A8F HEX

 MZSTOR.  Initialize Store  0  in /GCBANK/
          with Store/Table at absolute adrs    33632021   281557647
                                        HEX     2012F15    10C83A8F
                                        HEX    F138F25A           0
                              relative adrs  -247926182           0
          with     1 Str. in     2 Links in   5300 Low words in 2999970 words.
          This store has a fence of   16 words.
\end{verbatim}
\vdots
lots more messages

\vdots
\begin{verbatim}
 TOC1      0.171%; TSSW      0.001%; TSWC      0.083%; TSCE      0.000%; TWES      0.001%;
 TSWB      0.009%; TPEL      2.240%; TPMW      0.901%; TPEW      0.128%; TESR      0.000%;
 TESB      0.116%; TPLS      0.019%; TPUS      0.023%; TPSS      0.000%; THVM      0.012%;
 TPSR      0.052%; THVL      0.025%; FLTA      0.003%; FLTB      0.000%; FLTC      0.005%;
 FMYA      0.016%; FMYB      0.014%; FMYC      0.019%; FPLA      0.023%; FPLB      0.080%;
 FPLC      0.025%; FSTR      0.138%; FNSF      0.012%; FMYX      0.002%; FGRL      0.004%;
 FPAD      0.020%; FPEA      0.039%; FPEB      0.007%; FPEC      0.062%; FECA      0.058%;
 FECB      0.058%; FECC      0.053%; FWAA      0.096%; FWAB      0.148%; FWAC      0.073%;
 FBPA      0.057%; FBPB      0.018%; FBPC      0.085%; UAFI      0.109%; UAFM      0.018%;
 UAFO      0.044%; UAII      0.001%; UAIM      0.001%; UAIO      0.001%; UCFI      0.259%;
 UCFM      0.445%; UCFO      0.312%; UCII      0.000%; UCIM      0.000%; UCIO      0.000%;
 UL01      0.022%; UL02      0.006%; UL03      0.226%; UL04      0.006%; UL05      0.012%;
 UL06      0.001%; UL07      0.002%; UL08      0.081%; UL09      0.034%; UL10      0.038%;
 UL11      0.013%; TRD1      0.003%; TRD2      0.004%; TRD3      0.000%; BR2_      0.018%;
 CB2_      0.011%; R1R2      0.018%; R2R2      0.898%; R3R2      0.003%; R3L2      0.001%;
 R1R1      0.414%; R2R1      0.010%; R3R1      0.009%; R1L1      0.036%; R3L1      0.001%;
 CA02      0.016%; CG02      0.000%; CA03      0.042%; CG03      0.000%; EMCA      0.013%;
 PTXW      0.013%; PUFP      0.005%; PTCB      0.008%; PPAP      0.005%; PXTL      0.072%;
 PASP      0.026%; MPPS      0.004%; UAPP      0.000%; LCPP      0.037%; DW11      0.000%;
 DV11      0.000%; DPPB      0.659%; DPFE      0.157%; DPMD      0.000%; DIQU      0.016%;
***************************************************************************
root [1] 
\end{verbatim}

At this point a file called \texttt{galice.root} is created in your present
directory. This file contains all of the ``hits'' produced by the simulation,
all of the particle information, all of the detectors that were defined in the
simulation, and a lot of other information.
Commit	Line	Data
6b08d1be	1	\chapter*{Introduction}
	2	\section*{Purpose of this document}
	3
	4	This document is intended to both explain who to use the ALICE simulation and
	5	reconstruction code with respect to or using the ITS detector as the
	6	examples. This document is also to explain how to add new code to the ITS
	7	simulation and reconstruction library, and who the existing ITS simulation and
	8	reconstruction code works. All comments from every user is greatly encouraged.
	9
	10	\section*{How to Run AliRoot}
	11
	12	At this point, we will assume that aliroot has been compiled and all the
	13	necessary environment variables have been defined, including your path. We will
	14	assume you are in an appropriate directory, for example \texttt{/data} or some
	15	such thing.
	16
	17	to start with type, at your shell prompt, aliroot to start the program.
	18
	19	\begin{verbatim}
	20	# aliroot
	21	Constant Field Map1 created: map= 1, factor= 1.000000
	22	*******************************************
	23	* *
	24	* W E L C O M E to R O O T *
	25	* *
	26	* Version 2.26/00 10 November 2000 *
	27	* *
	28	* You are welcome to visit our Web site *
	29	* http://root.cern.ch *
	30	* *
	31	*******************************************
	32
	33	FreeType Engine v1.x used to render TrueType fonts.
	34	Compiled with thread support.
	35
	36	CINT/ROOT C/C++ Interpreter version 5.14.58, Oct 24 2000
	37	Type ? for help. Commands must be C++ statements.
	38	Enclose multiple statements between { }.
	39
	40	WELCOME to ALICE
	41
	42	root [0]
	43	\end{verbatim}
	44
	45	This will initialize ROOT and load all of the ALICE libraries. At this point you
	46	can do anything you can do in ROOT in addition you have access to every class
	47	defined in the ALICE libraries, including the ALICE global variables. One very
	48	useful ALICE global variable is \texttt{gAlice} which is of type
	49	\texttt{AliRun}. Of the many function defined in the class \texttt{AliRun} are
	50	\texttt{Init(const char* setup="Config.C")} and
	51	\texttt{Run(const char* setup="Config.C")}. \texttt{Run} both executes
	52	\texttt{Init} and starts executing an ALICE detector simulation. Both of these
	53	functions functions load and execute a configuration file. By default this
	54	configuration file is called \texttt{Config.C}. If such a file exists in your
	55	local directory, for example \texttt{/data}, or if there is no such file in
	56	your local directory it will execute the file
	57	\texttt{\$ALICE\_ROOT/macros/Config.C}. Some other configuration file can be
	58	run simplely by entering that file's name as the argument, for example
	59	\texttt{Init("MyConfig.C")} or \texttt{Run("MyConfig.C")} where
	60	\texttt{MyConfig.C} is either in your local directory (\texttt{/data}) or in
	61	\texttt{\$ALICE\_ROOT/macros}. Of course the full path of \texttt{MyConfig.C}
	62	can be used.
	63
	64	Now lets assume you just want to one event using the standard \texttt{Config.C}
65	file. This is done simply as
66	\begin{verbatim}
67	root [0] gAlice->Run()
68	Warning in <AliRun::SetField>: Invalid magnetic field flag: -999; Helix trackin
69	g chosen instead
70
71	Warning in <AliFRAMEv1::ReadEuclidMedia>: file: $(ALICE_ROOT)/Euclid/frame.tme i
72	s now read in
73
74	Warning in <AliPIPEv0::ReadEuclidMedia>: file: $(ALICE_ROOT)/Euclid/pipe.tme is
75	now read in
76
77	Warning in <AliITSv5::ReadEuclidMedia>: file: /home/CERN/aliroot/dev/Euclid/ITSg
78	eometry_5.tme is now read in
79
80
81	MZSTOR. ZEBRA table base TAB(0) in /MZCC/ at adr 281557647 10C83A8F HEX
82
83	MZSTOR. Initialize Store 0 in /GCBANK/
84	with Store/Table at absolute adrs 33632021 281557647
85	HEX 2012F15 10C83A8F
86	HEX F138F25A 0
87	relative adrs -247926182 0
88	with 1 Str. in 2 Links in 5300 Low words in 2999970 words.
89	This store has a fence of 16 words.
90	\end{verbatim}
91	\vdots
92	lots more messages
93
94	\vdots
95	\begin{verbatim}
96	TOC1 0.171%; TSSW 0.001%; TSWC 0.083%; TSCE 0.000%; TWES 0.001%;
97	TSWB 0.009%; TPEL 2.240%; TPMW 0.901%; TPEW 0.128%; TESR 0.000%;
98	TESB 0.116%; TPLS 0.019%; TPUS 0.023%; TPSS 0.000%; THVM 0.012%;
99	TPSR 0.052%; THVL 0.025%; FLTA 0.003%; FLTB 0.000%; FLTC 0.005%;
100	FMYA 0.016%; FMYB 0.014%; FMYC 0.019%; FPLA 0.023%; FPLB 0.080%;
101	FPLC 0.025%; FSTR 0.138%; FNSF 0.012%; FMYX 0.002%; FGRL 0.004%;
102	FPAD 0.020%; FPEA 0.039%; FPEB 0.007%; FPEC 0.062%; FECA 0.058%;
103	FECB 0.058%; FECC 0.053%; FWAA 0.096%; FWAB 0.148%; FWAC 0.073%;
104	FBPA 0.057%; FBPB 0.018%; FBPC 0.085%; UAFI 0.109%; UAFM 0.018%;
105	UAFO 0.044%; UAII 0.001%; UAIM 0.001%; UAIO 0.001%; UCFI 0.259%;
106	UCFM 0.445%; UCFO 0.312%; UCII 0.000%; UCIM 0.000%; UCIO 0.000%;
107	UL01 0.022%; UL02 0.006%; UL03 0.226%; UL04 0.006%; UL05 0.012%;
108	UL06 0.001%; UL07 0.002%; UL08 0.081%; UL09 0.034%; UL10 0.038%;
109	UL11 0.013%; TRD1 0.003%; TRD2 0.004%; TRD3 0.000%; BR2_ 0.018%;
110	CB2_ 0.011%; R1R2 0.018%; R2R2 0.898%; R3R2 0.003%; R3L2 0.001%;
111	R1R1 0.414%; R2R1 0.010%; R3R1 0.009%; R1L1 0.036%; R3L1 0.001%;
112	CA02 0.016%; CG02 0.000%; CA03 0.042%; CG03 0.000%; EMCA 0.013%;
113	PTXW 0.013%; PUFP 0.005%; PTCB 0.008%; PPAP 0.005%; PXTL 0.072%;
114	PASP 0.026%; MPPS 0.004%; UAPP 0.000%; LCPP 0.037%; DW11 0.000%;
115	DV11 0.000%; DPPB 0.659%; DPFE 0.157%; DPMD 0.000%; DIQU 0.016%;
116	***************************************************************************
117	root [1]
118	\end{verbatim}
119
120	At this point a file called \texttt{galice.root} is created in your present
121	directory. This file contains all of the ``hits'' produced by the simulation,
122	all of the particle information, all of the detectors that were defined in the
123	simulation, and a lot of other information.