v2.0.0 (2026-06-01)
===================

First release under the NLR fork (``NatLabRockies/pyvisco``).

Added
-----

- ``pyproject.toml`` (PEP 621) replaces ``setup.py`` / ``setup.cfg`` /
  ``versioneer.py``. Version is derived from Git tags via
  ``setuptools-scm`` (fallback ``1.0.5``).
- ``tests/`` test suite with 8 pytest cases covering ``load``, ``shift``,
  and ``prony`` modules.
- GitHub Actions workflows:

  - ``ci.yml`` — pytest matrix (Python 3.11 / 3.12 / 3.13 × Ubuntu /
    Windows) plus a ``ruff check`` + ``ruff format --check`` lint job.
  - ``notebooks.yml`` — ``nbval-lax`` execution check on the three
    ``verification/verify_*.ipynb`` notebooks, on
    ``LinViscoFit.ipynb`` (voila GUI) and on
    ``tutorials/tutorial.ipynb``, plus a smoke-test step that runs the
    three ``tutorials/*.py`` example scripts.
  - ``binder.yml`` — weekly + on-push rebuild of the Binder image via
    ``jupyterhub/repo2docker-action``.
  - ``release-assets.yml`` — builds ``pyvisco-examples.zip`` from the
    contents of ``sample_data/`` and uploads it to every published GitHub
    release.

- ``tutorials/`` folder with a non-interactive walkthrough notebook
  (``tutorial.ipynb``, the ``ipywidgets``-free counterpart of
  ``LinViscoFit.ipynb``) and three standalone scripts —
  ``freq_master.py``, ``freq_raw.py``, ``time_master.py`` — mirroring
  the three verification scenarios for headless / scripted use.
- ``verification/README.md`` and ``tutorials/README.md`` describing the
  contents and CI of each folder.
- This changelog.

Changed
-------

- **Breaking:** minimum Python is now 3.11 (was 3.7).
- **Breaking:** ``pandas >= 2.1`` is required; internal
  ``df.loc[i]['col'] = x`` patterns rewritten to ``df.loc[i, 'col'] = x``
  to satisfy the pandas 3.x ``ChainedAssignmentError``.
- **Breaking:** ``ipywidgets >= 8.1`` is required. The ``FileUpload``
  widget handling was rewritten for the new tuple-of-dicts ``value`` API
  (the ``_counter`` trait was removed upstream). A new
  ``_file_upload_bytes`` helper transparently supports both the v8 and v7
  payload formats.
- Dependency floors raised across the stack: ``numpy >= 1.26``,
  ``scipy >= 1.11``, ``matplotlib >= 3.8``, ``voila >= 0.5``,
  ``jupyterlab >= 4.1``, ``notebook >= 7.1``, ``openpyxl >= 3.1``,
  ``xlrd >= 2.0``.
- Optional ``[interactive]``, ``[app]``, and ``[excel]`` extras have been
  folded into the default install — ``pip install pyvisco`` now provides
  everything needed to run the dashboard.
- Binder environment moved to Python 3.13. The legacy top-level
  ``Dockerfile``, ``environment.yml``, and ``requirements.txt`` were
  removed; Binder config now lives entirely under ``binder/``.
- ReadtheDocs build switched from the unmaintained ``m2r2`` to
  ``myst-parser``.
- Documentation, package metadata, license, and Zenodo records updated to
  reflect the move from NREL to NLR (Natural Laboratory of the Rockies).
- Maintainer contact: ``martin.springer@nlr.gov``.
- Repository-wide ``ruff check`` + ``ruff format`` pass (line length 100,
  target ``py311``).

Fixed
-----

- Legacy ``.xls`` uploads no longer fail silently. ``xlrd`` is now a hard
  dependency and the ``@exceptions`` decorator on the upload observers
  has a catch-all branch that writes the traceback to both the output
  widget and ``sys.stderr`` (so the failure is visible in the Voila
  server log).
- ``verify.load_prony_ANSYS`` now captures the declared ``nterms`` from
  the ``TB,PRONY,...`` record and raises a descriptive ``ValueError`` if
  the parsed ``alpha_i`` / ``tau_i`` counts disagree with each other or
  with the declared count (replaces a silently-discarded ``int()`` call
  that could crash on unrelated ``TB`` records).
- ``out.to_csv`` docstring corrected: returns a CSV ``str`` when
  ``filepath`` is ``None``, otherwise writes to disk and returns
  ``None`` (previously documented as ``pandas.DataFrame`` / ``bytes``).

Removed
-------

- ``setup.py``, ``setup.cfg``, ``versioneer.py``, ``MANIFEST.in``,
  ``Procfile``, ``runtime.txt``, and the stale top-level ``build/`` tree.
- ``LinViscoFit-test.ipynb`` development sandbox.
- ``examples/examples.zip`` is no longer committed to the repository; it
  is now produced from ``sample_data/`` (renamed from ``examples/``) at
  release time and attached to the GitHub release as
  ``pyvisco-examples.zip``. The voila app's download link points at
  ``https://github.com/NatLabRockies/pyvisco/releases/latest/download/pyvisco-examples.zip``.
- Auto-generated ``docs/_autosummary/*.rst`` stubs are no longer tracked
  (they are regenerated by Sphinx on every build).

`Release tag on GitHub <https://github.com/NatLabRockies/pyvisco/releases/tag/v2.0.0>`_