Installation

The package can be installed via conda-forge:

conda install --channel "conda-forge" hsd-python

Alternatively, the package can be downloaded and installed via pip into the active Python interpreter (preferably using a virtual python environment) by

pip install hsd

or into the user space issueing

pip install --user hsd

Quick tutorial

A typical, self-explaining input written in HSD looks like

driver {
  conjugate_gradients {
    moved_atoms = 1 2 "7:19"
    max_steps = 100
  }
}

hamiltonian {
  dftb {
    scc = yes
    scc_tolerance = 1e-10
    mixer {
      broyden {}
    }
    filling {
      fermi {
        # This is comment which will be ignored
        # Note the attribute (unit) of the field below
        temperature [kelvin] = 100
      }
    }
    k_points_and_weights {
      supercell_folding {
        2   0   0
        0   2   0
        0   0   2
        0.5 0.5 0.5
      }
    }
  }
}

The above input can be parsed into a Python dictionary with:

import hsd
hsdinput = hsd.load("test.hsd")

The dictionary hsdinput will then look as:

{
    "driver": {
        "conjugate_gradients" {
            "moved_atoms": [1, 2, "7:19"],
            "max_steps": 100
        }
    },
    "hamiltonian": {
        "dftb": {
            "scc": True,
            "scc_tolerance": 1e-10,
            "mixer": {
                "broyden": {}
            },
            "filling": {
                "fermi": {
                    "temperature": 100,
                    "temperature.attrib": "kelvin"
                }
            }
            "k_points_and_weights": {
                "supercell_folding": [
                    [2, 0, 0],
                    [0, 2, 0],
                    [0, 0, 2],
                    [0.5, 0.5, 0.5]
                ]
            }
        }
    }
}

Being a simple Python dictionary, it can be easily queried and manipulated in Python

hsdinput["driver"]["conjugate_gradients"]["max_steps"] = 200

and then stored again in HSD format

hsd.dump(hsdinput, "test2.hsd")

License

The hsd-python package is licensed under the BSD 2-clause license.