v1.6.0

• Requirements

  • Increased minimum version of SeeK-path to 2.2.1

    • Recent updates provide improved compatibility with recent spglib versions
      and allow q-point paths to be generated in the input cell orientation.

  • Security

    • Bumped wheel requirement for docs and testing to 0.46.2. (CVE-2026-24049 <https://www.cve.org/CVERecord?id=CVE-2026-24049>_)

• Bug fixes

  • Band structures paths could be generated with incorrect
    correspondence of q-points to symmetry labels if the input cell
    was transformation of reference primitive cell. (e.g. different
    order of lattive vectors). This is now fixed by using features of
    SeeK-path 2.1+.

  • Band structure paths would be inappropriately generated and
    labelled if the input cell was a supercell of the primitive cell.
    This scenario now emits a warning (from Seek-path) and the tick
    labels will not use the traditional high-symmetry labels.

• Improvements

  • Extended pathlib.Path support and annotations throughout the code. Removing
    references to os.path where no longer relevant.

  • Rework Spectrum*.copy() to meet Python copy <https://docs.python.org/3/library/copy.html>__ specifications.

• Maintenance

  • Replace tmpdir in tests with tmp_path and use Path handling.

v1.5.1

• Requirements

  • Test requirements

    • Added pytest-xdist and pytest-cov requirements for parallel
      testing at pytest level.

• Bug fixes

  • Fix typing of calls to Spectrum.broaden() by brille_convergence
    and intensity_map command-line tools.

• Compatibility fixes

  • Fixed handling of new SpglibError class for expected errors from spglib 2.7.0
  • Include required arguments to np.divide call, avoiding deprecation
    warning which would trigger test failure.

• Maintenance

  • Reworked CI strategy from parallelism over tox environments to
    parallelism over unit tests. This addresses OpenMP conflicts
    between simultaneous test environments, and gives a large speedup
    when testing a single Python version. (i.e. typical local testing
    scenario before pushing to CI.)

  • Stopped testing every master push against Python 3.15

v1.5.0

• Requirements

  • Python 3.10-3.14 is supported

  • Test requirements

    • Migrated from pytest 7 to pytest 8

    • Migrated from pytest-lazy-fixture (which appears to be
      unmaintained and incompatible) to pytest-lazy-fixtures, an
      active project with similar functionality.

• Bug fixes

  • Added defences at runtime against OpenMP library conflicts. This
    scenario is most commonly encounted when using PyPI wheels for
    Euphonic and Brille on MacOS. If multiple OpenMP libraries are
    loaded, Euphonic will raise a warning and fallback to serial
    operation to reduce the risk of a deadlock or other unpleasant
    interaction.

    This is a known problem with OpenMP distributed in Python wheels,
    cited as a reason to avoid use of OpenMP in SciPy. See e.g.
    https://pypackaging-native.github.io/key-issues/native-dependencies/blas_openmp/

    To get high performance of Euphonic Fourier interpolation while
    loading another OpenMP-using library (such as brille) it may be
    necessary for users to build the software from source. (Pip
    install with --no-binary may be sufficient.) Compatibility can
    also be ensured when programs are distributed with a beyond-python
    package manager such as Conda or apt.

• Improvements

  • Improved error message when C extension import fails due to
    missing dynamic libraries.

  • Random sampling functions (including deterministic sampling
    functions with a random jitter option) accept a new rng
    parameter for a numpy.random Generator (generally preferred) or
    RandomState (used for testing). This allows the user to manipulate
    the random seed and bit generator to ensure reproducible or
    independent calculations.

  • The default argument to rng is a quasi-global Generator
    instance in euphonic.util. This avoids the computational
    overhead of creating a new generator every time a random function
    is called.

• Maintenance

  • Bumped cibuildwheel to v3.3.0

  • Bumped github action versions: actions/checkout@v6, actions/setup-python@v6

  • Started testing with Python 3.15 pre-release. (Currently there are
    Numpy build problems, this is ok.)

  • On Mac, unit tests with and without brille are run separately. This
    enables full OpenMP parallelism for tests that don't require
    brille to be loaded.

v1.4.5

Features

• CLI tools will now accept phonopy data produced by janus-core, with filenames in the form "{label}-phonopy.yml" and "{label}-force_constants.hdf5".

Bug fixes

• Fixed a bug in subtraction of dipole-dipole contribution from force constants with non-symmetric supercell matrix. This affects import from Phonopy results where

  a) Born effective charges and dielectric tensor were included;
  b) sc_matrix != sc_matrix.T .

Maintenance

• Pytest configuration has been moved from tests_and_analysis/test/pytest.ini to the main pyproject.toml. This means it is more likely to be picked up automatically when running tests outside of the CI workflows.

• Some Einstein summations have been replaced with equivalent matrix multiplications; this should improve performance and legibility.

• Fixed a unit test which used pytest.approx() incorrectly.

v1.4.4

• Requirements

  • The minimum required version of spglib is increased to 2.1.0

• Bug fixes

  • euphonic-intensity-map incorrectly rejecting files with phonon
    mode data for coherent scattering calculations. (Introduced in
    v1.4.3.)

• Maintenance

  • Numpy random number generators have been updated to use a Generator from
    np.random.default_rng
  • Improved test coverage of error states

v1.4.3

• Features

  • Add methods get_bin_edges, get_bin_centers to
    Spectrum2DCollection, making interface consistent with other
    Spectrum classes.

• Bug fixes

  • Fix tox version number in Pyproject.toml; installation with [ci]
    "extra" was broken.
  • Fix the mode_gradients_unit argument to
    euphonic.readers.castep.read_phonon_dos_data; this was
    returning consistent data/units but ignoring the preference
    expressed in that argument.

• Maintenance

  • Avoid incompatible-pointer-types in C compilation; this is an
    error in GCC14 and warning in older versions.

  • Moved unit register definition to new "ureg" module. This is to defend against
    internal import loops: users remain welcome to access things via
    from euphonic import ureg, Quantity.

  • Introduced ruff-based linting with a (fair-sized) subset of rules enabled.

    • This cleanup may have introduced some small improvements to error and
      warning messages.

    • The executable bits on some files have changed, for better
      consistency and to express more clearly how they are used.

  • Improved test coverage, removed some unused code

v1.4.2

• Bug fixes

  • Make Spectrum directly accessible from euphonic.spectra. (This was
    accidentally lost in a refactor, affecting downstream that uses
    Spectrum as a type annotation.)

v1.4.1

• Bug fixes

  • CASTEP 25.1 allows Born effective charges to be calculated by
    Berry Phase methods without a corresponding dielectric tensor. In
    such cases, no long-range term can be subtracted from the Force
    Constants (or reconstructed). Euphonic uses the presence of Born
    effective charges to indicate such a subtraction; to prevent
    ill-defined cases, ForceConstants now sets both Born charges and
    dielectric tensor to None if only one was provided.

  • An optional parameter is provided to change how bin edges are
    obtained from bin centres: previously the bin edges were constrained
    to the initial data range, but this can lead to incorrect scaling
    when performing broadening. Variable-width broadening schemes are
    now allowed to extrapolate the bin edges in order to get the correct
    width scaling.

    Outside of broadening, the default behaviour is unchanged in order
    to maintain backward compatibility. This is likely to be changed
    in the next "major version" (i.e. API-breaking release) of
    Euphonic.

• Maintenance

  • The euphonic.spectra module has been broken up into a subpackage
    with the single-spectrum classes defined in euphonic.spectra.base
    and the collections in euphonic.spectra.collections. This is not a
    breaking change: the public classes, functions and type annotations
    remain importable from euphonic.spectra.

  • CASTEP 25.1 includes an extra field in .castep_bin files,
    indicating whether Born effective charges were read from an
    external file. For clarity and safety, this field is now
    explicitly read by the Euphonic .castep_bin parser, but remains unused.

  • The release process has been reworked to reduce manual steps: a
    top-level "release" action will now sequence most of the
    steps. (Post-release testing is still separate.)

v1.4.1rc2

This pre-release was created to test changes to release workflow. See v1.4.1rc1 for summary of changes.

v1.4.1rc1

• Bug fixes

  • CASTEP 25.1 allows Born effective charges to be calculated by
    Berry Phase methods without a corresponding dielectric tensor. In
    such cases, no long-range term can be subtracted from the Force
    Constants (or reconstructed). Euphonic uses the presence of Born
    effective charges to indicate such a subtraction; to prevent
    ill-defined cases, ForceConstants now sets both Born charges and
    dielectric tensor to None if only one was provided.

  • An optional parameter is provided to change how bin edges are
    obtained from bin centres: previously the bin edges were constrained
    to the initial data range, but this can lead to incorrect scaling
    when performing broadening. Variable-width broadening schemes are
    now allowed to extrapolate the bin edges in order to get the correct
    width scaling.

    Outside of broadening, the default behaviour is unchanged in order
    to maintain backward compatibility. This is likely to be changed
    in the next "major version" (i.e. API-breaking release) of
    Euphonic.

• Maintenance

  • The euphonic.spectra module has been broken up into a subpackage
    with the single-spectrum classes defined in euphonic.spectra.base
    and the collections in euphonic.spectra.collections. This is not a
    breaking change: the public classes, functions and type annotations
    remain importable from euphonic.spectra.

  • CASTEP 25.1 includes an extra field in .castep_bin files,
    indicating whether Born effective charges were read from an
    external file. For clarity and safety, this field is now
    explicitly read by the Euphonic .castep_bin parser, but remains unused.

  • The release process has been reworked to reduce manual steps: a
    top-level "release" action will now sequence most of the
    steps. (Post-release testing is still separate.)