To use i-PI with already existing drivers, install using Pip:

$ pip install git+https://github.com/i-pi/i-pi.git

To develop i-PI or test it with the self-contained driver, follow these instructions. It is assumed that i-PI will be run from a Linux environment, with a recent version of Python, Numpy and gfortran, and that the terminal is initially in the i-pi package directory (the directory containing this file).

Source the environment settings file env.sh as $ source env.sh or $ . env.sh. It is useful to put this in your .bashrc or other settings file if you always want to have i-PI available.

$ cd drivers
$ make
$ cd ..

This will first start the wrapper in the background, redirecting the output to a log file, and then run a couple of instances of the driver code. The progress of the wrapper is followed by monitoring the log file with the tail Linux command.

Optionally, you can make a copy of the directory with the example somewhere else if you want to keep the i-PI directory clean.

$ cd examples/tutorial/tutorial-1/
$ i-pi tutorial-1.xml > log &
$ i-pi-driver -h localhost -p 31415 -m sg -o 15 &
$ i-pi-driver -h localhost -p 31415 -m sg -o 15 &
$ tail -f log

The monitoring can be interrupted with CTRL+C when the run has finished (5000 steps).

The automatic test suite can be run with the Python package pytest from the root directory of the i-PI project.

$ pytest -v

Format Compliance ================

i-PI code should be compliant to a minimal subset of PEP-8 recommendations. Currently, we require the use of black as formatter and flake8 as linter. In most systems, both packages can be easily installed using pip. BEFORE proceeding to a pull request, the minimal requirement is that you run

$ make -f Makefile.style lint
$ make -f Makefile.style pretty 

This will ensure the formatting and linting requirement are applied in the whole directory tree. Please resolve any warnings or errors that may appear. Your commit will not pass the CI tests otherwise.

For a more flexible setup, we also provide the script i-pi-style, for which instructions can be obtained by typing

$ i-pi-style -h 

i-PI is an open source project, and everyone is welcome to contribute with bug fixes, documentation, examples, new features, regression tests, etc.

Your contribution should be based on the master branch. We kindly ask you to first fork the project, make your changes, make sure you comply with all items in our checklist below, and finally create a pull request (PR).

Checklist to create a pull request:

• The PR follows our format compliance (black and flake8 as explained above)
• All the new classes and functions include the corresponding docstrings

(If the PR adds a new functionally, please fulfill the next two requirements as well)

• Add a working example to the examples foldes to showcase the new functionality
• Add a regression test to the i-pi/ipi_tests/regression_tests folder (see the corresponding README file for further details)
• Make sure that all the automatic checks pass without any error

We are looking forward to your contribution!

i-PI is an open source project, and everyone is welcome to contribute with bug fixes, documentation, examples, new features, regression tests, etc.

Your contribution should be based on the master branch. We kindly ask you to first fork the project, make your changes, make sure you comply with all items in our checklist below, and finally create a pull request (PR).

Checklist to create a pull request:

• Code follows our format compliance (black and flake8 as explained above)

- All classes and functions include corresponding docstrings (If the PR adds a new functionally, please fulfill the next two requirements as well) - Add a working example to the examples foldes to showcase the new functionality - Add a regression test to the i-pi/ipi_tests/regression_tests folder (see the corresponding README file for further details) - Make sure that all the automatic checks pass without any error

We are looking forward to your contribution!