Installation instructions

1) Setup the environment

$ ./configure <config_file> (--production | --development)

For example you can type ./configure config/gfortran.cfg --production

This command will :

• Download and install all the requirements. Installing OCaml and the Core library may take some time (up to 20min on an old machine).
• Create the file which contains all the dependencies for the binaries. It's not a Makefile, but a Ninja file (so don't type make is hopeless, type ninja instead)

By default, the OCaml compiler and libraries will be installed in $HOME/.opam. If you want to install it somewhere else, you can change this by setting the $OPAMROOT environment variable to the location of your choice. For more info about the OCaml installation, you can visit the Opam website : https://opam.ocaml.org/doc/Install.html

Compilation Flags (<config_file>)

<config_file> is the path to the file which contains all the flags useful for the compilation : optimization flags, Lapack libary, etc. We have two default configuration files in $QP_ROOT/config : ifort.cfg and gfortran.cfg. You copy these files to create a new config file adapted to your architecture.

Note that the popcnt instruction accelerates a lot the programs, so the SSE4.2, AVX or AVX2 instruction sets should be enabled if possible.

If you encounter an error saying that your Fortran compiler can't produce executables, it means that the program was built using an instruction set not supported by the current processor. In that case, use the -ax option of the Intel Fortran compiler instead of the -x option, or the -march=native option of gfortran.

What utilization of the code will you do?

• If you only want the binaries (for production workflow) use the flag --production when calling this script. It builds faster.
• Else if you are a developer and you want to be able to compile specific modules, --development. It will create for you the build.ninja file in each module.

2) Set environment variables

A configuration file named quantum_package.rc will be created. To finish the installation and to start using the quantum package, source this file in your shell::

`source quantum_package.rc`

And you can also source it inside your .bashrc file, or create a system-wide module file.

If you use a C-shell, you will have to translate the quantum_package.rc file into C-shell syntax and source it in your shell.

Optional) Add some new modules

The quantum package has no executable out of the box. You need to install (and then compile) some modules. The qp_module.py will help you.

       qp_module.py create -n <name> [<children_modules>...]
       qp_module.py download -n <name> [<path_folder>...]
       qp_module.py install <name>...
       qp_module.py list (--installed | --available-local)
       qp_module.py uninstall <name>

For exemple you can type : qp_module.py install Full_CI. This will install the Full_CI module. All the modules are installed in the $QP_ROOT/src/, and all the available modules are in $QP_ROOT/plugins/

3) Compiling the Fortran

Just type ninja if you are in $QP_ROOT (or ninja -f $QP_ROOT/build.ninja elsewhere). The compilation will take approximately 3 min.

If you have set the --developement flag in a specific module you can go in the corresponding module $QP_ROOT/src/module_name directory and run ninja to build only this module. You can type ninja all in a module to compile all the submodules.

4) Testing if all is OK

Some unit tests are available in the test directory. To run the tests:

 cd $QP_ROOT/tests
 ./run_tests.sh