Installation and configuration guide

Introduction

EleFits depends on Elements, a Euclid-developed build framework based on CMake. As such, EleFits can be used either from an Elements project or from a CMake project. Euclid developers benefit from the continuous delivery of EDEN (Euclid development environment) and have nothing to install. Others must install EleFits (and Elements) before they configure their project.

Download, install and test EleFits

EDEN users

Nothing to install: all versions of EleFits are already part of EDEN. Jump to the configuration section.

Non-EDEN users

TL;DR

Download and run the installation script:

wget https://raw.githubusercontent.com/CNES/EleFits/5.3.1/install.sh
chmod +x install.sh
sudo ./install.sh

More details

In the remaining, we assume that you're putting the source code of Elements and EleFits in some <root> directory.

You'll first need to get Elements:

cd <root>
git clone -b 6.2.1 https://github.com/astrorama/Elements.git
cd Elements
mkdir build ; cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr/local ..
sudo make install

Finally, install EleFits the same way:

cd <root>
git clone -b 5.3.1 https://github.com/cnes/EleFits.git
cd EleFits
mkdir build ; cd build
cmake -DCMAKE_INSTALL_PREFIX=/usr/local -DCMAKE_PREFIX_PATH=/usr/local ..
sudo make install

This will install the the set of libraries in /usr/local/lib (or usr/local/lib64), headers in /usr/local/include, and executables in /usr/local/bin. The end-user library is named EleFits, while the low-level API is named EleCfitsioWrapper.

An install script is provided to perform all those steps, install.sh. Check the help as:

install.sh -h

Configure a project to depend on EleFits

Elements project

An Elements project is made of modules. The project contains a root CMakeLists.txt, and each module contains a CMakeLists.txt. For more information, please refer to the Elements documentation.

Using the package means declaring the dependency to the EleFits project in the root CMakeLists.txt:

elements_project(<project_name> <project_version>
    USE EleFits <EleFits_version>)

and to the EleFits module in the CMakeLists.txt of each module which requires EleFits:

elements_depends_on_subdirs(EleFits)
 
elements_add_executable(<program_name> src/program/<program_name>.cpp
    LINK_LIBRARIES ElementsKernel EleFits)
 
elements_add_library(<library_name> src/Lib/*.cpp
    LINK_LIBRARIES ElementsKernel EleFits
    INCLUDE_DIRS ElementsKernel EleFits
    PUBLIC_HEADERS <library_name>)

CMake project

Here's a minimal CMakeLists.txt file to use the EleFits library (end-user API):

CMAKE_MINIMUM_REQUIRED(VERSION <cmake_version>)
project(<project_name>)
list(APPEND CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/cmake/modules)
find_package(EleFits REQUIRED)
add_executable(<exe_name> <exe_source>)
target_link_libraries(<exe_name> EleFits)

The find_package command expects parent folder of the file FindEleFits.cmake to be in the CMAKE_MODULE_PATH. For now, this file is located in the sources of EleFits, in cmake/modules (we'd like it to be installed in a more standard location in some future version). To work with the proposed CMakeLists.txt, it should be copied inside your project:

cd <root>/<project_name>
wget https://raw.githubusercontent.com/CNES/EleFits/5.3.1/cmake/modules/FindEleFits.cmake -P cmake/modules
mkdir build ; cd build
cmake ..
make

Note that, to run executables, the EleFits library has to be in the library path. This can be done, for example, with:

export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib:/usr/local/lib64

which can be added to the .bashrc, e.g.:

echo 'export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib:/usr/local/lib64' >> ~/.bashrc
source ~/.bashrc