26.4.1. Installation instructions

The package has an external dependency on Hydra, ROOT and TCLAP. To fully exploit Hydra’s features you may need to install additional libraries. For example, CUDA is required to use Nvidia GPUs. Please refer to the instructions provided in the Hydra GitHub repository for more information.

You can download Hydra from GitHub

git clone https://github.com/MultithreadCorner/Hydra.git

The examples in this repository have been tested with Hydra release 3.2.1, but you are advised to use the master branch. If you experience any problems using the master branch, please open a GitLab issue so that we can keep the examples up-to-date with recent versions of Hydra. To switch to release 3.2.1, instead, just do

cd Hydra git checkout -b v3.2.1

If TCLAP is not installed in your system, download also TCLAP from http://tclap.sourceforge.net (Hydra and TCLAP are header-only libraries and do not need to be compiled, downloading them is enough).

Assuming you have ROOT installed, you can compile all fitting examples by executing the following commands from the hydra subdirectory of the b2-fitting-training repository:

mkdir build
cd build
cmake -D HYDRA_INCLUDE_DIR=path_to_hydra_dir -D TCLAP_INCLUDE_DIR=path_to_tclap_dir ../
make
cd -

If you work at KEKCC, setup a recent basf2 release to get ROOT and configure cmake by explicitly setting gcc/g++ as compilers with

cmake -D CMAKE_C_COMPILER=`which gcc` -D CMAKE_CXX_COMPILER=`which g++` -D HYDRA_INCLUDE_DIR=path_to_hydra_dir -D TCLAP_INCLUDE_DIR=path_to_tclap_dir ../

For each example program there is always a .cu and a .cpp source file in the src directory. These file have the same include statement of a .inl file containing the actual source code implementing the program. Cmake determines which backends are available and generates a Makefile to compile the code accordingly. The compiled executables will be in the bin directory. For each example you will find different executables compiled against the available backends. The name convention is example_{cpp,tbb,omp,cu} for standard (single-threaded) C++, TBB (multi-threaded CPU), OpenMP (multi-threaded CPU), CUDA (Nvidia GPU) executables, respectively. Usage instruction are printed when running each example with the -h argument, e.g.

./bin/simple-1d-fit_cpp -h