Software/Geant4/Installation/CLHEP

Introduction

CLHEP is intended to be a set of HEP-specific foundation and utility classes such as random generators, physics vectors, geometry and linear algebra. CLHEP is structured in a set of packages independent of any external package.

Geant4 requires the CLHEP libraries in order to compile simulations. By default Geant4 distributes a minimal version of the CLHEP library sources with the toolkit to help cross-platform usage. This internal version of the CLHEP library is built and used by default, so having an external install of CLHEP is no longer a prerequisite for Geant4.

However, the BDSIM accelerator simulation toolkit, which uses Geant4 for particle-matter interactions, requires a standalone version of CLHEP to be compiled separately from Geant4. As such, the instructions below relate to the standalone version of CLHEP.

Details

Website

http://proj-clhep.web.cern.ch/proj-clhep/

Source URL

http://proj-clhep.web.cern.ch/proj-clhep/DISTRIBUTION/

Installed version

2.3.1.1 (15 Mar 2016)

Source code

src/geant4-prerequisites/clhep/2.3.1.1

Installation Notes

The CLHEP website provides some documentation on building and installing standalone CLHEP libraries at http://proj-clhep.web.cern.ch/proj-clhep/INSTALLATION/clhep-2.0.html .

According to the release notes, http://geant4.web.cern.ch/geant4/support/ReleaseNotes4.10.2.html, the supported version of CLHEP for Geant4.10.2.p01 is 2.3.1.1. Using other versions of CLHEP may produce incorrect simulation results.

Installation

When downloading software, the downloaded tarball (or other Zip archive) should be placed in an appropriately named directory in /unix/pbt/software/src: the instructions below assume that the directory is /unix/pbt/software/src/clhep. The tarball should then be extracted into the same subdirectory.

For CLHEP, the tarball is named clhep-2.3.1.1.tgz. When extracted, this produces a directory called 2.3.1.1. Therefore, you will end up with a directory called /unix/pbt/software/src/clhep/2.3.1.1 containing the CLHEP source code:

Source Code Extraction

cd /unix/pbt/software/src/clhep
tar -xvzf clhep-2.3.1.1.tgz

Build And Install

Development Environment

cd /unix/pbt/software/build
mkdir -pv clhep/clhep-2.3.1.1
cd clhep/clhep-2.3.1.1
cmake -DCMAKE_INSTALL_PREFIX=/unix/pbt/software/dev/clhep-2.3.1.1 /unix/pbt/software/src/geant4-prerequisites/clhep/2.3.1.1/CLHEP
make
make install

Production Environment

It may be possible to install in the production environment by running cmake again and changing the install prefix, then running make install:

cd /unix/pbt/software/build/clhep/clhep-2.3.1.1
cmake -DCMAKE_INSTALL_PREFIX=/unix/pbt/software/prod .
make install

This will save having to compile the code again. If this does not work, the compilation steps for the development environment (above) will need to be repeated in another build directory:

cd /unix/pbt/software/build
mkdir -pv clhep/clhep-2.3.1.1-prod
cd clhep/clhep-2.3.1.1-prod
cmake -DCMAKE_INSTALL_PREFIX=/unix/pbt/software/prod /unix/pbt/software/src/clhep/2.3.1.1/CLHEP
make
make install