v1.2.0

• Improvements:

  • Euphonic now tests on Python 3.11
  • Euphonic now provides PyPI wheels for Python 3.11

• New features:

  • You can now perform linear interpolation of phonon frequencies and
    eigenvectors with the Brille <https://brille.github.io/stable/index.html>_
    library using the new
    euphonic.brille.BrilleInterpolator object. This should provide
    performance improvements for large unit cells which require the
    dipole correction.
  • There is a new command-line tool euphonic-brille-convergence to
    assist with choosing the BrilleInterpolator.from_force_constants
    arguments to achieve the desired accuracy.
  • Brille interpolation can be accessed from the euphonic-powder-map tool
    using the new --use-brille, --brille-grid-type, --brille-npts
    and --brille-npts-density arguments.

v1.1.0

• New features:

  • There is a new function ForceConstants.from_total_fc_with_dipole to allow
    reading force constants from other programs which contain long-ranged
    dipole-dipole interactions.

• Bug fixes:

  • Avoid occasional segmentation faults when using OpenBLAS, workaround for
    #191 <https://github.com/pace-neutrons/Euphonic/issues/191>_
  • Correctly read force constants from Phonopy with dipole-dipole
    interactions, see #239 <https://github.com/pace-neutrons/Euphonic/issues/239>_.

v1.0.0

• Changes:

  • Support for Python 3.6 has been dropped. This has also resulted in
    changes to the following dependencies:

    • numpy requirement increased from 1.12.1 to 1.14.5
    • scipy requirement increased from 1.0.0 to 1.1.0
    • pint requirement increased from 0.9 to 0.10.1
    • matplotlib requirement increased from 2.0.0 to 2.2.2
    • h5py requirement increased from 2.7.0 to 2.8.0

  • The following deprecated features have been removed:

    • The return_mode_widths argument in ForceConstants.calculate_qpoint_phonon_modes
      and ForceConstants.calculate_qpoint_frequencies has been removed
    • The eta_scale argument in calculate_qpoint_phonon_modes/frequencies
      has been removed
    • The alias command-line tool argument --weights has been removed
    • The alias arguments x_label, y_label, y_min and y_max to
      plot_1d/2d have been removed
    • The modes_from_file and force_constants_from_file functions from
      euphonic.cli.utils have been removed
    • Calling broaden on a Spectrum with uneven bin widths without
      specifying the method='convolve' argument will now raise a ValueError

  • DOS and PDOS calculated by the calculate_dos and
    calculate_dos_map methods of QpointPhononModes and
    QpointFrequencies, and QpointPhononModes.calculate_pdos are
    now calculated per atom rather than per unit cell (integrated area
    is 3 rather than 3*N_atom). This is to keep consistency with
    the structure factors calculated by
    QpointPhononModes.calculate_structure_factor which are calculated
    per atom.

  • The option average_repeat_points when importing q-point modes or
    frequencies from a CASTEP .phonon file with
    QpointFrequencies/QpointPhononModes.from_castep is now True
    by default. To recover previous behaviour set this to False.

v0.6.5

• New Features:

  • Kinematic constraints have been implemented for 2-D S(q,w)-like data.

    • A function euphonic.spectra.apply_kinematic_constraints(Spectrum2d, **kwargs) -> Spectrum2D
      is implemented which masks out inaccessible data, replacing it with NaN.
    • Both direct-geometry and indirect-geometry are supported, by
      using the appropriate argument to set incident or final neutron energy.
    • This function is exposed to the euphonic-powder-map tool, so these
      plots can be produced directly from the CLI.
    • Some parameters from real-world instruments are collected in the
      documentation for convenience.

  • There is a new function euphonic.util.convert_fc_phases, which converts
    a force constants matrix which uses the atom coordinates in the phase
    during interpolation (Phonopy-like), to one which uses the cell origin
    coordinates (Euphonic, CASTEP-like).

  • When importing q-point modes or frequencies from a CASTEP .phonon
    file, a new option (average_repeat_points=True) allows
    repeated entries (with the same q-point index) to be identified
    and their weights divided down by the number of entries. This
    option should give better statistics for sampling meshes that
    include the Gamma-point with LO-TO splitting.

• Improvements:

  • Documentation on the shape and format of the force constants, and how to
    read them from other programs has been improved.

  • The euphonic.util.get_qpoint_labels function, which is called when
    importing band-structure data to identify and label significant points,
    primarily identifies these points by searching for turning-points
    in the band path. The function will now also pick up any q-point
    that appears twice in succession. This is a common convention in
    band-structure calculations and helps with edge-cases such as when
    the path passes through a high-symmetry point without changing
    direction. This may pick up some previously-missing points in
    band-structure plots generated with euphonic-dispersion and
    euphonic-intensity-map

• Bug fixes:

  • Allow read of phonopy.yaml quantities in 'au' (bohr) units.
    Previously this was interpreted as an astronomical unit by Pint.

v0.6.4

• Improvements:

  • The euphonic-dos, euphonic-dispersion and
    euphonic-intensity-map command-line tools can now read
    files that don't contain eigenvectors, if eigenvectors are
    not required for the chosen options.

  • A new --save-json option is available for command-line tools
    which produce plots, this will output the produced spectrum to
    a Euphonic .json file.

  • There is now the option to use a fast, approximate variable-width broadening method when
    adaptively broadening dos:

    • Added new adaptive_method and adaptive_error arguments for calculate_dos
      which specify which adaptive broadening method to use (reference or fast) and an
      acceptable error level when using the fast method.
    • Fast adaptive broadening can be used in the euphonic-dos tool with the
      --adaptive-method and --adaptive-error arguments.

• Changes:

  • euphonic.cli.force_constants_from_file and modes_from_file
    have been deprecated in favour of euphonic.cli.load_data_from_file.
  • Using Spectrum1D/1DCollection/2D.broaden on an axis with unequal
    bin widths is now deprecated, as broadening is performed via convolution,
    which is incorrect in this case. In the future, this will raise a
    ValueError. To broaden anyway, method='convolve' can be supplied,
    which will just emit a warning.

v0.6.3

• New Features:

  • New Spectrum1D.to_text_file and Spectrum1DCollection.to_text_file
    methods to write to column text files

  • An expanded and consistent set of styling options is made
    available for command-line tools that produce plots.

  • Consistent styling and advanced changes can be made using
    Matplotlib stylesheet files, either as a CLI argument or
    using matplotlib.style.context() in a Python script.

• Improvements:

  • Internally, plot theming has been adjusted to rely on Matplotlib
    style contexts. This means user changes and style context are more
    likely to be respected.
  • Additional aliases for plot arguments in the command-line tools have
    been added, for example either --x-label or --xlabel can be used.

• Changes:

  • x_label, y_label, y_min and y_max in euphonic.plot
    functions have been deprecated in favour of xlabel, ylabel,
    ymin and ymax respectively, to match the Matplotlib arguments
    they refer to, and to match other arguments like vmin, vmax.

v0.6.2

• Improvements:

  • Wheels are now provided with PyPI releases
  • Type hinting is now handled more consistently across different Euphonic
    classes and functions

• Bug Fixes:

  • Will no longer raise a KeyError reading from phonopy.yaml if
    physical_unit key is not present, instead will assume default units
  • Can now read Phonopy BORN files where the (optional) NAC conversion
    factor is not present

v0.6.1

• Bug fixes:

  • The scaling of S(Q,w) as produced by StructureFactor.calculate_sqw_map
    was incorrect, and did not correctly scale with energy bin size (given its
    units are now length**2/energy). This has been fixed, and S(Q,w) scale
    has changed by a factor of (hartee to energy bin unit conversion)/(energy
    bin width magnitude). e.g. if using an energy bin width of 0.1 meV, the new
    S(Q,w) will be scaled by 2.72e4/0.1 = 2.72e5. The original structure factors
    can now be correctly recovered by multiplying S(Q,w) by the energy bin width.

v0.6.0

• Euphonic can now calculate neutron-weighted partial density of states, and
  has new Spectra features to handle PDOS data:

  • Added QpointPhononModes.calculate_pdos method
  • Added QpointFrequencies.calculate_dos_map method
  • New Spectrum1D.__add__ method, which adds 2 spectra together
  • New Spectrum1DCollection.__add__ method, which concatenates 2 collections
  • Enabled indexing of Spectrum1DCollection by a sequence
  • Added Spectrum1DCollection.group_by method, which allows grouping and
    summing spectra by metadata keys e.g. group_by('species')
  • Added Spectrum1DCollection.select method, which allows selection
    of spectra by metadata keys e.g. select(species='Si')
  • Added Spectrum1DCollection.sum method, which sums all spectra in a
    collection
  • Added -w={'coherent-dos','incoherent-dos','coherent-plus-incoherent-dos'}
    neutron-weighted PDOS options to euphonic-dos and euphonic-powder-map
  • Added --pdos options for plotting specific species PDOS to
    euphonic-dos and euphonic-powder-map
  • Deprecated --weights command-line argument in favour of --weighting
    for consistency with calculate_pdos

• Improvements:

  • LICENSE and CITATION.cff <https://citation-file-format.github.io/>_
    files are now included in Euphonic's installation
  • Add ability to interactively change the colormap intensity limits
    in euphonic-powder-map
  • euphonic-optimise-dipole-parameter can now read from Phonopy sources
  • euphonic-optimise-dipole-parameter can now also be used for non-polar
    materials to get general per-qpoint timings
  • Dimensioned Euphonic properties (e.g. frequencies, cell_vectors)
    now have setters so can be set, previously this would raise an
    AttributeError

• Changes:

  • The units of density of states as produced by calculate_dos have
    changed from dimensionless to 1/energy
  • The scaling of density of states has also changed. Previously the
    integration would sum to 1 (if the x_data were converted to Hartree
    units), now the integration will sum to 3N in the same units as x_data
  • StructureFactor.structure_factors have been changed to be in absolute
    units per atom (rather than per unit cell) so will have changed by a
    factor of 1/2*n_atoms, this formulation change has been reflected in the
    calculate_structure_factor docstring
  • The default unit of StructureFactor.structure_factors has been changed
    from angstrom**2 to millibarn
  • The unit of S(Q,w) as produced by StructureFactor.calculate_sqw_map
    has changed dimension from length**2 to length**2/energy. Also,
    as its unit is derived from the input StructureFactor object, its
    default units are now millibarn/meV
  • The eta_scale argument in calculate_qpoint_phonon_modes has been
    deprecated, dipole_parameter should be used instead.
  • This means the euphonic-optimise-eta script has been renamed to
    euphonic-optimise-dipole-parameter.

v0.5.2

• Improvements:

  • Added broaden method to Spectrum1DCollection

• Changes:

  • The return_mode_widths argument in calculate_qpoint_phonon_modes
    has been deprecated in favour of return_mode_gradients. The mode
    widths can still be obtained from the mode gradients with
    util.mode_gradients_to_widths

• Bug fixes:

  • Fixed memory leak when using the C extension and making multiple calls to
    calculate_qpoint_phonon_modes/frequencies
  • Fixed bug which resulted in incorrect energy bins being generated
    in euphonic-powder-map if units other than meV are used and
    --e-max and --e-min aren't specified
  • Use correct number of energy bins in euphonic-intensity-map,
    euphonic-powder-map and euphonic-dos. Previously only
    ebins - 1 bins were generated