pyALF

The package implements ALF's python interface. pyALF greatly simplifies using the code, making it ideal for:

• obtaining benchmark results for established models;
• getting started with QMC and ALF;
• or just quickly running a simulation with ALF.

Prerequisites

• Python
• Jupyter
• the libraries Lapack and Blas
• a Fortran compiler, such as gfortran or ifort,

where the last two are required by the main package ALF.

Also, add pyALF's path to your environment variable PYTHONPATH. In Linux, this can be achieved, e.g., by adding the following line to .bashrc:

export PYTHONPATH="/local/path/to/pyALF:$PYTHONPATH"

Usage

Jupyter notebooks are run through a Jupyter server started, e.g., from the command line:

jupyter notebook

or

jupyter-notebook

which opens the "notebook dashboard" in your default browser, where you can navigate through your file structure to the pyALF directory. There you will find the interface's core module, py_alf.py, some auxiliary files, and a number of notebooks.

However, pyALF can also be used to start a simulation from the command line, without starting a Jupyter server. For instance:

python3.7 Run.py -R  --alfdir /home/debian/ALF-1.2/ --config "Intel"  --executable_R Hubbard --mpi True  &

Notice that Run.py assumes the existence of the configuration file Sims, which defines the simulation parameters. A line of Sims might read as:

{"Model": "Hubbard", "Lattice_type": "Square", "L1": 4 , "L2": 4, "NBin": 5, "ham_T": 0.0, "Nsweep" : 2000, "Beta": 1.0, "ham_chem": -1.0 }

Files and directories

• py_alf.py - provides interfaces for compilig, running and postprocessing ALF in Python
• default_variables.py - defines dictionaries containing all ALF parameters with default values
• Run.py - helper script for compiling, running and testing ALF
• Sims - configuration for running directly from the command line
• Notebooks - directory containing Jupyter notebooks

License

The various works that make up the ALF project are placed under licenses that put a strong emphasis on the attribution of the original authors and the sharing of the contained knowledge. To that end we have placed the ALF source code under the GPL version 3 license (see license.GPL and license.additional) and took the liberty as per GPLv3 section 7 to include additional terms that deal with the attribution of the original authors(see license.additional). The Documentation of the ALF project by the ALF contributors is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License (see Documentation/license.CCBYSA) We mention that we link against parts of lapack which licensed under a BSD license(see license.BSD).