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| 3 | <TITLE>More Geant4 FAQ</TITLE> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1">
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| 5 | <!--
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| 8 | </HEAD>
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| 9 |
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| 10 | <BODY BGCOLOR="#FFFFFF" BACKGROUND="../icons/backg.jpg">
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| 11 | <DIV ALIGN="center">
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| 12 | <P>
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| 13 | <IMG SRC="../icons/g4_small.gif" WIDTH="312" HEIGHT="76">
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| 14 | </P>
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| 15 | </DIV><DIV ALIGN="center"> <H1>Frequently Asked Questions</H1><H1> </H1></DIV>
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| 16 | <P>
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| 17 | <P>
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| 18 | <P>
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| 19 |
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| 20 | <UL>
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| 21 | <LI> <B><A NAME="q-general"></A><A HREF="#a-general">General</A></B>
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| 22 | <OL>
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| 23 | <LI><A HREF="#gen-1">How do I add a FAQ to this page?</A></LI>
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| 24 | </OL>
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| 25 | </LI>
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| 26 | <BLOCKQUOTE>
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| 27 | <P> </P>
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| 28 | </BLOCKQUOTE>
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| 29 | <LI><B><A NAME="q-install"></A><A HREF="#a-install">Installation</A></B>
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| 30 | <OL>
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| 31 | <LI><A HREF="#install-1">When I download the source from the web, and unpack
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| 32 | the tar file, some files unpack into the top level directory.</A> </LI>
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| 33 | <LI><A HREF="#install-2">I cannot find CLHEP files or library and I have it
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| 34 | installed in my system</A>. </LI>
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| 35 | <LI><a href="#install-3">I installed CLHEP and the "Hist"
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| 36 | package for histogramming is missing. Where can I find it and how can
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| 37 | I do for making histograms.</a> </LI>
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| 38 | <LI><a href="#install-4">While installing the Geant4 libraries I get the
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| 39 | following message printed:</a><br>
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| 40 | <code> gmake[1]: cernlib:
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| 41 | Command not found</code> <br>
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| 42 | <a href="#install-4">Has Geant4 been installed properly ? What to do to
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| 43 | solve this error ? </a> </LI>
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| 44 | <LI><a href="#install-5">Trying building the Geant4 libraries I see several
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| 45 | of these errors appearing and my installation fails:</a><br>
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| 46 | <code> .....G4Exception.d:1:
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| 47 | *** missing separator. Stop.<br>
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| 48 | </code><code>...../G4DalitzDecayChannel.d:1:
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| 49 | *** missing separator. Stop. <br>
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| 50 | :<br>
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| 51 | : </code>
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| 52 | <br>
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| 53 | <a href="#install-5">Has Geant4 been installed properly ? What to do to
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| 54 | solve this error ? </a> </LI>
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| 55 | <LI><a href="#install-6">I'm trying to build Geant4 on Linux Red-Hat
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| 56 | 7.0/7.1 with gcc-2.96.XX and get errors in compilation or when building
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| 57 | the file dependencies.</a> </LI>
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| 58 | <LI><a href="#install-7">Trying to install Geant4 on Linux with gcc-3.X
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| 59 | compiler, I get compilation errors from CLHEP/DRand48Engine. </a> </LI>
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| 60 | </OL>
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| 61 | </LI>
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| 62 | <BLOCKQUOTE>
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| 63 | <P> </P>
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| 64 | </BLOCKQUOTE>
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| 65 | <LI><B><A NAME="q-run"></A><A HREF="#a-run">Runtime Problems</A></B>
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| 66 | <OL>
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| 67 | <LI><A HREF="#runtime-1">On Linux Red-Hat 6.1, I get a segmentation fault
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| 68 | as soon as I run one of the official extended examples. I also noticed
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| 69 | that random engine status is not stored on file.</A>
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| 70 | </LI>
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| 71 | <LI><a href="#runtime-2">I installed Geant4 libraries and built my application,
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| 72 | when I try to run it I get:</a><br>
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| 73 | <code>
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| 74 |
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| 75 | error in loading shared libraries:<br>
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| 76 |
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| 77 | libCLHEP.so: cannot open shared object file:<br>
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| 78 |
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| 79 | No such file or directory</code>.
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| 80 | </LI>
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| 81 | <LI><A HREF="#runtime-3">On my system I get a Floating Point Exception
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| 82 | (FPE) since some physics processes sometimes return DBL_MAX as interaction
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| 83 | length and this number is afterwards multiplied by a number greater than
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| 84 | 1.</A>
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| 85 | </LI>
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| 86 | </OL>
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| 87 | </LI>
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| 88 | <BLOCKQUOTE>
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| 89 | <P> </P>
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| 90 | </BLOCKQUOTE>
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| 91 | <LI><A NAME="q-geometry"></A><B><A HREF="#a-geometry">Geometry</A></B>
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| 92 | <OL>
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| 93 | <LI><A HREF="#a-geom-1">I have a generic point and I would like to know
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| 94 | in which physical volume I'm located in my detector geometry.</A></LI>
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| 95 | <LI><A HREF="#a-geom-2">How can I access the daughter volumes of a specific
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| 96 | physical volume?</A></LI>
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| 97 | <LI><A HREF="#a-geom-3">How can I identify the exact copy-number of a specific
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| 98 | physical volume in my mass geometry? I tried with <code>GetCopyNo()</code>
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| 99 | from my physical volume pointer, but it doesn't seem to work!</A></LI>
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| 100 | <LI><A HREF="#a-geom-4">How can I determine the exact position in global coordinates
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| 101 | in my mass geometry during tracking and how can I convert it to coordinates local to
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| 102 | the current volume ?</A></LI>
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| 103 | </OL>
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| 104 | </LI>
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| 105 | <BLOCKQUOTE>
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| 106 | <P> </P>
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| 107 | </BLOCKQUOTE>
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| 108 | <LI><B><A NAME="q-phys"></A><A HREF="#a-phys">Physics and cuts</A></B>
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| 109 | <OL>
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| 110 | <LI><A HREF="#PHYS-1">How do production cuts (in range) work in Geant4 ?
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| 111 | Are they also used in tracking ? If a particle has an energy lower than the
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| 112 | converted cut in energy for the given material and the distance to the next
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| 113 | boundary is smaller than the cut in range, is the particle killed ?</A>
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| 114 | </OL>
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| 115 | </LI>
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| 116 | <BLOCKQUOTE>
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| 117 | <P> </P>
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| 118 | </BLOCKQUOTE>
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| 119 | <LI><B><A NAME="q-vis"></A><A HREF="#a-vis">Visualization</A></B>
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| 120 | <OL>
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| 121 | <LI><A HREF="#VIS-1">I have set G4VIS... environmental variables but visualization
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| 122 | does not appear to be enabled.</A>
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| 123 | <LI><A HREF="#VIS-2">Geant4 crashes while trying to open an OpenGLX window.</A>
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| 124 | </OL>
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| 125 | </LI>
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| 126 | </UL>
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| 127 |
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| 128 | <HR>
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| 129 |
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| 130 | <H3><A NAME="a-general"></A><A HREF="#q-general">General</A></H3>
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| 131 | <OL>
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| 132 | <LI><A NAME="gen-1"></A><I>How do I add a FAQ to this page?</I>
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| 133 | <BR><BR>
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| 134 | <I>Solution:</I><BR>
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| 135 | This is done manually at the moment. Please send your FAQ with solution
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| 136 | to the <A HREF="mailto:Gunter.Folger@cern.ch, Gabriele.Cosmo@cern.ch">editors</A>.
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| 137 | </LI>
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| 138 | </OL>
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| 139 |
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| 140 | <HR>
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| 141 |
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| 142 | <H3> <A NAME="a-install"></A><A HREF="#q-install">Installation</A> </H3>
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| 143 | <OL>
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| 144 | <LI><A NAME="install-1"></A><I>When I download the source from the web, and unpack
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| 145 | the tar file, some files unpack into the top level directory.</I><BR>
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| 146 | <BR>
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| 147 | <I>Solution:</I><BR>
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| 148 | The problem you describe usually is the result of using "UNIX" tar to
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| 149 | unpack the gtar ("GNU-tar") file, or vice versa, or using zip on either the
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| 150 | gtar or tar file. Please make certain that you download the correct file for
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| 151 | your system, and that you use the correct unpacking tool. Note that for Linux
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| 152 | you must download the gtar.gz file.<P>
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| 153 | </LI>
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| 154 | <LI><A NAME="install-2"></A><I>I cannot find CLHEP files or library and I have
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| 155 | it installed in my system.</I><BR>
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| 156 | <BR>
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| 157 | <I>Solution:</I><BR>
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| 158 | If the standard CLHEP installation procedure has been adopted, the variable
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| 159 | $CLHEP_BASE_DIR should point to the area where include/ and lib/ directories
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| 160 | for CLHEP headers & lib are installed (i.e., it should be /usr/local for the
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| 161 | default CLHEP installation). In case the library name is different than the
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| 162 | one expected (libCLHEP.a), you should either create a symbolic link with the
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| 163 | expected name, or define the variable CLHEP_LIB in your environment which
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| 164 | explicitly sets the name of the CLHEP library. If a non-standard CLHEP installation
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| 165 | has been adopted, define variables $CLHEP_INCLUDE_DIR, $CLHEP_LIB_DIR (and
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| 166 | $CLHEP_LIB) to refer explicitly to the place where includes, library (and
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| 167 | library-name) respectively are placed in your system.<P>
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| 168 | </LI>
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| 169 | <li><a name="install-3"></a><i>I installed </i>CLHEP<i> and the
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| 170 | "</i>Hist<i>" package for histogramming is missing. Where can I find it and
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| 171 | how can I do for making histograms.</i><br>
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| 172 | <br>
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| 173 | <i>Solution:</i><br>
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| 174 | In Geant4, histogramming is done through the standard AIDA interface;
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| 175 | these histograms can be displayed or otherwise manipulated using analysis
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| 176 | tools based on the AIDA interface (JAS, Lizard, Open Scientist, ...). Examples
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| 177 | are shown in examples/extended/analysis and examples/advanced applications.
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| 178 | <br>
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| 179 | <br>
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| 180 | The obsolete and no-longer maintened "Hist" module can be downloaded from
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| 181 | the <a href="http://pcitapiww.cern.ch/asd/lhc++/INSTALLATION/clhep-1.5.html">
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| 182 | CLHEP 1.5 distribution from web</a>, but requires some modifications to the
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| 183 | CLHEP installation scripts to be properly installed.<P>
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| 184 | </li>
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| 185 | <li><a name="install-4"></a><i>While installing the Geant4 libraries I get
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| 186 | the following message printed:</i><br>
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| 187 |
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| 188 | gmake[1]: cernlib: Command not found <br>
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| 189 | <i>Has Geant4 been installed properly ? What to do to solve this error ?</i><br>
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| 190 | <br>
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| 191 | <i>Solution:</i><br>
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| 192 | The message:<br>
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| 193 | <code>
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| 194 | gmake[1]: cernlib: Command not found
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| 195 | </code> <br>
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| 196 | shows that you don't have the 'cernlib' command installed in your system;
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| 197 | 'cernlib' is a command from the CERN program library (cernlib) returning a
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| 198 | list of libraries needed to link a cernlib application. This command is only
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| 199 | used in the 'g3tog4' module, however, if you do not make use of the 'g3tog4'
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| 200 | tool, it's harmless. The cernlib script (and the needed cernlib libraries)
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| 201 | are available from: <a href="http://cern.ch/cernlib">http://cern.ch/cernlib</a>.<P>
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| 202 | </li>
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| 203 | <li><a name="install-5"></a> <i>Trying building the Geant4 libraries I see several
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| 204 | of these errors appearing and my installation fails:</i><br>
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| 205 | <code>
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| 206 | .....G4Exception.d:1:
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| 207 | *** missing separator. Stop.<br>
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| 208 |
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| 209 | ...../G4DalitzDecayChannel.d:1:
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| 210 | *** missing separator. Stop. <br>
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| 211 |
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| 212 | :<br>
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| 213 |
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| 214 | :
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| 215 | </code> <br>
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| 216 | <i>Has Geant4 been installed properly ? What to do to solve this error ?</i><br>
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| 217 | <br>
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| 218 | <i>Solution:</i><br>
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| 219 | It looks like some file dependencies (.d) are corrupted, possibly
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| 220 | due to previous build attempts which failed for some reason.<br>
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| 221 | You need to remove each of them; you can use:
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| 222 | <pre>
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| 223 | gmake dependencies='' clean
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| 224 | </pre>
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| 225 | from the affected module (i.e. for this case, from
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| 226 | $G4INSTALL/source/global/management and
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| 227 | $G4INSTALL/source/particles/management)
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| 228 | and rebuild.
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| 229 | <br>Alternatively, you may use:
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| 230 | <pre>
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| 231 | gmake clean
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| 232 | </pre>
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| 233 | from geant4/source and rebuild.<P>
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| 234 | </li>
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| 235 | <li><a name="install-6"></a><i>I'm trying to build Geant4 on Linux Red-Hat
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| 236 | 7.0/7.1 with gcc-2.96.XX and get errors in compilation or when building
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| 237 | the file dependencies.</i><br>
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| 238 | <br>
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| 239 | <i>Solution:</i><br>
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| 240 | Geant4 is supported on Red Hat 6.1 with gcc-2.95.2. Moreover, note
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| 241 | that on versions 7.X, Red Hat Linux is distributed with a flawed version of
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| 242 | the gcc compiler which has -never- been officially released by GNU. The compiler
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| 243 | gcc-2.96.XX may require strict ISO/ANSI setup. If so the following changes
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| 244 | in Geant4 3.2 may help to build most of the modules in Geant4, although we
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| 245 | cannot guarantee a correct behavior of a program built with such compiler.
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| 246 | In geant4/config/sys/Linux-g++.gmk modify the line:<br>
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| 247 | <code> CXXFLAGS := -pipe -fno-for-scope -DGNU_GCC</code><br>
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| 248 | to<br>
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| 249 | <code> CXXFLAGS := -ansi -pedantic -pipe -fno-for-scope
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| 250 | -DGNU_GCC</code><br>
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| 251 | <br>
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| 252 | And the following lines:<br>
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| 253 | <code> </code><code>ifdef G4USE_OSPACE<br>
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| 254 | CPPFLAGS += -DOS_LINUX_2 -DOS_NEW_CHECK -DOS_STL_ASSERT<br>
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| 255 | CPPFLAGS += -DOS_NO_WSTRING -DOS_NO_ALLOCATORS<br>
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| 256 | CPPFLAGS += -I$(OSPACE_BASE_DIR)/ospace/std
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| 257 | -I$(OSPACE_BASE_DIR)<br>
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| 258 | # else<br>
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| 259 | # G4USE_STD_NAMESPACE := yes<br>
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| 260 | # CPPFLAGS += -DG4USE_STD_NAMESPACE<br>
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| 261 | endif</code><br>
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| 262 | to:<br>
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| 263 | <code> </code><code>G4USE_STD_NAMESPACE := yes<br>
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| 264 | CPPFLAGS += -DG4USE_STD_NAMESPACE</code><br>
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| 265 | <br>
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| 266 | Rebuild from scratch:<br>
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| 267 | <code> </code> <code>cd geant4/source<br>
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| 268 | gmake clean<br>
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| 269 | gmake<br>
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| 270 | </code><P>
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| 271 | </li>
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| 272 | <li><a name="install-7"></a><i>Trying to install Geant4 on Linux with gcc-3.X
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| 273 | compiler, I get compilation errors from CLHEP/DRand48Engine.</i><br>
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| 274 | <br>
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| 275 | <i>Solution:</i><br>
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| 276 | To overcome this problem on gcc-3.X, you should reinstall CLHEP and
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| 277 | comment out or remove the lines included between <br>
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| 278 | <code>
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| 279 | #if !defined(__GNUC__) || defined(__STRICT_ANSI__) <BR>
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| 280 | ... <BR>
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| 281 | #endif <br></code>
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| 282 | in DRand48Engine.h. <br>
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| 283 | This problem is fixed in a higher (>1.7) version of the CLHEP package.
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| 284 | </li>
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| 285 | </ol>
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| 286 |
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| 287 | <HR>
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| 288 |
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| 289 | <H3><A NAME="a-run"></A><A HREF="#q-run">Run Time Problems</A> </H3>
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| 290 | <OL>
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| 291 | <LI><A NAME="runtime-1"></A><I>On Linux Red-Hat 6.1, I get a segmentation fault
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| 292 | as soon as I run one of the official extended examples. I also noticed that
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| 293 | random engine status is not stored on file.</I><BR>
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| 294 | <BR>
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| 295 | <I>Solution:</I><BR>
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| 296 | Check that the CLHEP library has been installed and compiled with Red-Hat
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| 297 | 6.1. A binary object produced with Red-Hat 5.X is not fully compatible with
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| 298 | binaries running on RH 6.X, due to a different libc used in the two configurations.<P>
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| 299 | </li>
|
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| 300 | <li><a name="runtime-2"></a><i>I installed Geant4 libraries and built my application,
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| 301 | when I try to run it I get:</i><br>
|
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| 302 | <code>
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| 303 |
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| 304 | error in loading shared libraries:<br>
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| 305 |
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| 306 | libCLHEP.so: cannot open shared object file:<br>
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| 307 |
|
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| 308 | No such file or directory.
|
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| 309 | </code><br>
|
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| 310 | <br>
|
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| 311 | <i>Solution:</i><br>
|
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| 312 | Your installation of CLHEP includes shared libraries. You need to specify
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| 313 | the path where libCLHEP.so is installed through your environment variable
|
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| 314 | LD_LIBRARY_PATH.<P>
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| 315 | </li>
|
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| 316 | <LI><A NAME="runtime-3"></A><I>On my system I get a Floating Point Exception
|
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| 317 | (FPE) since some physics processes sometimes return </I>DBL_MAX<I> as interaction
|
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| 318 | length and this number is afterwards multiplied by a number greater than 1.</I><BR>
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| 319 | <BR>
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| 320 | <I>Solution:</I><BR>
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| 321 | Geant4 coding conventions and installation setup explicitly follow the ANSI/IEEE-754
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| 322 | Standard for the initialization of floating-point arithmetic hardware and
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| 323 | portability. The Standard foresees floating-point arithmetic to be nonstop
|
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| 324 | and underflows to be gradual. On DEC platforms, for example, the ANSI/IEEE-754
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| 325 | Standard compliance needs to be explicitly set (since deactivated by default);
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| 326 | in this case we use infact the option "-ieee" on the DEC/cxx native C++ compiler
|
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| 327 | to achieve this. You should check if your compiler provides compilation options
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| 328 | for activating Standard initialization of FP arithmetic (it may be platform
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| 329 | specific).
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| 330 | </LI>
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| 331 | </OL>
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| 332 |
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| 333 | <HR>
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| 334 |
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| 335 | <H3><A NAME="a-geometry"></A><A HREF="#q-geometry">Geometry</A> </H3>
|
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| 336 | <OL>
|
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| 337 | <LI><A NAME="a-geom-1"></A><I>I have a generic point and I would like to know
|
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| 338 | in which physical volume I'm located in my detector geometry.</I>
|
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| 339 | <BR><BR>
|
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| 340 | <I>Solution:</I><BR>
|
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| 341 | The best way of doing this is by invoking the G4Navigator. First get a pointer
|
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| 342 | of the navigator through the G4TransportationManager, and then locate the point.
|
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| 343 | i.e.
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| 344 | <pre>
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| 345 | #include "G4TransportationManager.hh"
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| 346 | #include "G4Navigator.hh"
|
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| 347 | G4ThreeVector myPoint = ....;
|
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| 348 | G4Navigator* theNavigator = G4TransportationManager::GetTransportationManager()->GetNavigatorForTracking();
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| 349 | G4VPhysicalVolume* myVolume = theNavigator->LocateGlobalPointAndSetup(myPoint);
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| 350 | </pre>
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| 351 | </LI>
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| 352 | <LI><A NAME="a-geom-2"></A><I>How can I access the daughter volumes of a specific
|
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| 353 | physical volume?</I>
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| 354 | <BR><BR>
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| 355 | <I>Solution:</I><BR>
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| 356 | Through the associated logical volume.
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| 357 | <pre>
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| 358 | G4VPhysicalVolume* myPVolume = ....;
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| 359 | G4LogicalVolume* myLVolume = myPVolume->GetLogicalVolume();
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| 360 | for (G4int i=0; i<myLVolume->GetNoDaughters(); i++)
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| 361 | myPVolume = myLVolume->GetDaughter(i);
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| 362 | </pre>
|
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| 363 | </LI>
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| 364 | <LI><A NAME="a-geom-3"></A><I>How can I identify the exact copy-number of a specific
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| 365 | physical volume in my mass geometry? I tried with <code>GetCopyNo()</code>
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| 366 | from my physical volume pointer, but it doesn't seem to work!</I>
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| 367 | <BR><BR>
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| 368 | <I>Solution:</I><BR>
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| 369 | The correct way to identify -uniquely- a physical volume in your
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|---|
| 370 | mass geometry is by using the touchables (see also section 4.1.5 of the
|
|---|
| 371 | User's Guide for Application Developers), as follows:
|
|---|
| 372 | <pre>
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|---|
| 373 | G4Step* aStep = ..;
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|---|
| 374 | G4StepPoint* preStepPoint = aStep->GetPreStepPoint();
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| 375 | G4TouchableHandle theTouchable = preStepPoint->GetTouchableHandle();
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| 376 | G4int copyNo = theTouchable->GetReplicaNumber();
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| 377 | G4int motherCopyNo = theTouchable->GetReplicaNumber(1);
|
|---|
| 378 | </pre>
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|---|
| 379 | where <code>Replica</code> here stays for any duplicated instance of a physical
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| 380 | volume, either if it is a <code>G4PVPlacement</code> (multiple placements of the
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|---|
| 381 | same logical volume) or a <code>G4PVReplica</code>/<code>G4PVParameterised</code>.<BR>
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|---|
| 382 | The method <code>GetCopyNo()</code> is meant to return only the serial
|
|---|
| 383 | number of placements not duplicated in the geometry tree.<P>
|
|---|
| 384 | </LI>
|
|---|
| 385 | <LI><A NAME="a-geom-4"></A><I>How can I determine the exact position in global coordinates
|
|---|
| 386 | in my mass geometry during tracking and how can I convert it to coordinates local to
|
|---|
| 387 | the current volume ?</I>
|
|---|
| 388 | <BR><BR>
|
|---|
| 389 | <I>Solution:</I><BR>
|
|---|
| 390 | You need again to do it through the touchables (see also section 4.1.5 of the
|
|---|
| 391 | User's Guide for Application Developers), as follows:
|
|---|
| 392 | <pre>
|
|---|
| 393 | G4Step* aStep = ..;
|
|---|
| 394 | G4StepPoint* preStepPoint = aStep->GetPreStepPoint();
|
|---|
| 395 | G4TouchableHandle theTouchable = preStepPoint->GetTouchableHandle();
|
|---|
| 396 | G4ThreeVector worldPosition = preStepPoint->GetPosition();
|
|---|
| 397 | G4ThreeVector localPosition = theTouchable->GetHistory()->
|
|---|
| 398 | GetTopTransform().TransformPoint(worldPosition);
|
|---|
| 399 | </pre>
|
|---|
| 400 | where <code>worldPosition</code> here stays for the position related to the world
|
|---|
| 401 | volume, while <code>localPosition</code> refers to the coordinates local to the
|
|---|
| 402 | volume where the particle is currently placed.
|
|---|
| 403 | </LI>
|
|---|
| 404 | </OL>
|
|---|
| 405 |
|
|---|
| 406 | <HR>
|
|---|
| 407 |
|
|---|
| 408 | <H3><A NAME="a-phys"></A><A HREF="#q-phys">Physics and cuts</A> </H3>
|
|---|
| 409 | <OL>
|
|---|
| 410 | <LI><I><A NAME="PHYS-1"></A>How do production cuts (in range) work in Geant4 ?
|
|---|
| 411 | Are they also used in tracking ? If a particle has an energy lower than the
|
|---|
| 412 | converted cut in energy for the given material and the distance to the next
|
|---|
| 413 | boundary is smaller than the cut in range, is the particle killed ?</I>
|
|---|
| 414 | <BR><BR>
|
|---|
| 415 | <I>Answer:</I><BR>
|
|---|
| 416 | Geant4 does NOT have a "tracking cut". The toolkit's default behaviour
|
|---|
| 417 | is to track particles down to zero range (i.e. zero energy).<BR>
|
|---|
| 418 | Of course, it is possible for the user to create and register a process
|
|---|
| 419 | that kills particles below a certain energy or range; this is however
|
|---|
| 420 | NOT provided by default in Geant4. So there's NO "tracking cut".<BR>
|
|---|
| 421 | For example, suppose a particle that is nearing zero energy will at some point
|
|---|
| 422 | be proposed by its Ionisation process to undergo one final step, from its current
|
|---|
| 423 | energy down to zero energy. This is still only a proposal. If during this step
|
|---|
| 424 | the particle crosses a boundary, then the transportation will limit the step at
|
|---|
| 425 | a length smaller than the Ionisation -- so the particle will still see and cross
|
|---|
| 426 | the relevant boundary, and another step will occur on the other side of that
|
|---|
| 427 | boundary.<BR>
|
|---|
| 428 | In summary the "production threshold" range and its equivalent in
|
|---|
| 429 | energy are not utilised as a "tracking cut". A particle is not abandoned
|
|---|
| 430 | by Geant4 below a certain range/energy unless the user registers a process
|
|---|
| 431 | to do this by him/her-self.
|
|---|
| 432 | </LI>
|
|---|
| 433 | </OL>
|
|---|
| 434 |
|
|---|
| 435 | <HR>
|
|---|
| 436 |
|
|---|
| 437 | <H3><A NAME="a-vis"></A><A HREF="#q-vis">Visualization</A> </H3>
|
|---|
| 438 | <OL>
|
|---|
| 439 | <LI><I><A NAME="VIS-1"></A>I have set G4VIS... environmental variables but visualization
|
|---|
| 440 | does not appear to be enabled.</I>
|
|---|
| 441 | <BR><BR>
|
|---|
| 442 | <I>Solution:</I><BR>
|
|---|
| 443 | This might be
|
|---|
| 444 | because you set the environment variables *after* already compiling. The environment
|
|---|
| 445 | variables control C-pre-processor macros of the same name and therefore influence
|
|---|
| 446 | what code gets compiled. I suggest: (setenv or export the environment variables)
|
|---|
| 447 | <PRE>
|
|---|
| 448 | cd $G4INSTALL/source/visualization
|
|---|
| 449 | gmake clean
|
|---|
| 450 | gmake
|
|---|
| 451 | cd $G4INSTALL/source/interfaces
|
|---|
| 452 | gmake clean
|
|---|
| 453 | gmake
|
|---|
| 454 | cd $G4INSTALL/source
|
|---|
| 455 | gmake libmap
|
|---|
| 456 | cd [your working directory]
|
|---|
| 457 | gmake clean
|
|---|
| 458 | gmake
|
|---|
| 459 | </PRE>
|
|---|
| 460 | Try environment variables <CODE>G4VIS_BUILD_xxx_DRIVER</CODE>
|
|---|
| 461 | and <CODE>G4VIS_USE_xxx</CODE>, where xxx = <CODE>OPENGLX, DAWN, DANWFILE, VRML,
|
|---|
| 462 | VRMLFILE</CODE> all set to 1.<P>
|
|---|
| 463 | </LI>
|
|---|
| 464 | <LI><I><A NAME="VIS-2"></A>Geant4 crashes while trying to open an OpenGLX window.</I>
|
|---|
| 465 | <BR><BR>
|
|---|
| 466 | <I>Solution:</I><BR>
|
|---|
| 467 | This might be because you are using Mesa-3.1. Mesa-3.0 works.
|
|---|
| 468 | </LI>
|
|---|
| 469 | </OL>
|
|---|
| 470 |
|
|---|
| 471 | <HR>
|
|---|
| 472 | Wednesday, 21 May 2003 -
|
|---|
| 473 | <I> <A HREF="http://consult.cern.ch/xwho/people/20341">GC</A>,
|
|---|
| 474 | <A HREF="http://consult.cern.ch/xwho/people/1342">GF</A>
|
|---|
| 475 | </I>
|
|---|
| 476 | </BODY>
|
|---|
| 477 | </HTML>
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