Ampform

_See all documentation for this version [here](//ampform.rtfd.io/en/0.14.2)._

✨ New features

- Implemented [`improve_latex_rendering()`](https://ampform.readthedocs.io/en/0.14.2/api/ampform.io.html#ampform.io.improve_latex_rendering) (300)
- Implemented [`logging` hierarchy](https://docs.python.org/3/library/logging.html#logger-objects) (320)
- [SymPy v1.11](https://github.com/sympy/sympy/wiki/release-notes-for-1.11) is now supported (#325)

⚠️ Changes that may affect behavior

- Insert parity prefactor as [`sympy.Rational`](https://docs.sympy.org/latest/modules/core.html#sympy.core.numbers.Rational) (322)

📝 Documentation

- Documentation on [`formulate_wigner_d()`](https://ampform.readthedocs.io/en/0.14.2/api/ampform.helicity.html#ampform.helicity.formulate_wigner_d) has been improved (312)

🔨 Maintenance

- Switched from [`sphinx-panels`](https://sphinx-panels.readthedocs.io) to [`sphinx-design`](https://sphinx-design.readthedocs.io) (#299)
- Switch to [`black`](https://black.readthedocs.io)'s default 88 line width (#298)

🖱️ Developer Experience

- [New ComPWA commit types and PR labels](https://github.com/ComPWA/.github/issues/7#issuecomment-1209318257) are now enforced (323)

_See all documentation for this version [here](//ampform.rtfd.io/en/0.14.1)._

💡 New features

- Implemented first version of [`ampform.io`](https://ampform.readthedocs.io/en/0.14.1/api/ampform.io.html) sub-module (#280)
- Implemented [Kibble](https://ampform.readthedocs.io/en/0.14.1/api/ampform.kinematics.phasespace.html#ampform.kinematics.phasespace.Kibble) and [Källén](https://ampform.readthedocs.io/en/0.14.1/api/ampform.kinematics.phasespace.html#ampform.kinematics.phasespace.Kallen) functions (292)

⚠️ Interface

- [Spin alignment](https://ampform.readthedocs.io/en/0.14.1/usage/helicity/spin-alignment.html) is now deactivated by default (#295)

🖱️ Developer Experience

- All dependencies on are now pinned on Read the Docs as well (276)
- Documentation is now built with [`sphinx-build`](https://www.sphinx-doc.org/en/master/man/sphinx-build.html) (through `tox`) only, not through with `make` (#286)

_See all documentation for this version [here](https://ampform.rtfd.io/en/0.14.0)._

💡 New features

- Extracted [`formulate_form_factor()`](https://ampform.readthedocs.io/en/0.14.0/api/ampform.dynamics.html#ampform.dynamics.formulate_form_factor) function (262)</summary>
- Implemented [`PhaseSpaceFactorSWave`](https://ampform.readthedocs.io/en/0.14.0/api/ampform.dynamics.phasespace.html#ampform.dynamics.phasespace.PhaseSpaceFactorSWave), which uses the Chew-Mandelstam _S_-wave as a phase space factor (265)</summary>

⚠️ Interface

- Renamed PhaseSpaceFactorAnalytic to [`EqualMassPhaseSpaceFactor`](https://ampform.readthedocs.io/en/0.14.0/api/ampform.dynamics.phasespace.html#ampform.dynamics.phasespace.EqualMassPhaseSpaceFactor) (264)
- Moved phase space factor definitions to [`ampform.dynamics.phasespace`](https://ampform.readthedocs.io/en/0.14.0/api/ampform.dynamics.phasespace.html) (#266)
- Naming functions return a [sympy.Symbol](https://docs.sympy.org/latest/modules/core.html#sympy.core.symbol.Symbol) instead of [`str`](https://docs.python.org/3/library/stdtypes.html#str) (269)
- [`ComplexSqrt`](https://ampform.readthedocs.io/en/0.14.0/api/ampform.sympy.math.html#ampform.sympy.math.ComplexSqrt) is now blocked from 'unfolding' (270)
- Assumptions on some parameter and variable symbols have changed (271)

🐛 Bug fixes

- Implemented hash method for [`EnergyDependentWidth`](https://ampform.readthedocs.io/en/0.14.0/api/ampform.dynamics.html#ampform.dynamics.EnergyDependentWidth) (274)

📝 Documentation

- Updated references to [PDG2021](https://pdg.lbl.gov/2021/reviews/rpp2021-rev-resonances.pdf) (#262)
- Fixed comparison [visualization widget](https://ampform.readthedocs.io/en/0.14.0/usage/dynamics.html#analytic-continuation) for analytic continuation (272)
- Fixed [2D complex plane widget](https://ampform.readthedocs.io/en/0.14.0/usage/dynamics/k-matrix.html#interactive-visualization) for K-matrix (273)

_See all documentation for this version [here](https://ampform.rtfd.io/en/0.13.3)._

💡 New features

- It's now possible to generate [helicity couplings](https://ampform.readthedocs.io/en/0.13.3/usage/amplitude.html#helicity-couplings) instead of amplitude coefficients (256)

🔨 Internal maintenance

- It's now possible to install AmpForm with [patches of SymPy v1.10](https://github.com/sympy/sympy/wiki/release-notes-for-1.10.1) (#258)

_See all documentation for this version [here](https://ampform.rtfd.io/en/0.13.2)._

💡 New features

* Implemented coefficient naming switch (252)

⚠️ Interface

* Dropped support for Python 3.6 (249)
* Adapted implementations to SymPy v1.10 (249)

🔨 Internal maintenance

* Simplified type hints with PEP 563 (250)

📝 Documentation

* Added simple code examples to main usage page (255)

_See all documentation for this version [here](https://ampform.rtfd.io/en/0.13.1)._

💡 New features

<details>
<summary>Implemented spin alignment for mismatching decay topologies (6 and 245)</summary>

See problem description in [TR-015](https://compwa-org.readthedocs.io/report/015.html) and usage example [here](https://ampform--245.org.readthedocs.build/en/245/usage/helicity/spin-alignment.html). For an example with generated data, see [TR-013](https://compwa-org.readthedocs.io/report/013.html).

</details>


⚠️ Interface

<details>
<summary>Helicity angle notation is now more concise (208 and 209)</summary>

Compare [old notation](https://ampform.readthedocs.io/en/0.12.2/api/ampform.kinematics.html#ampform.kinematics.get_helicity_angle_label) and [new notation](https://ampform--209.org.readthedocs.build/en/209/api/ampform.kinematics.html#ampform.kinematics.get_helicity_angle_label).

</details>

<details>
<summary>Removed decay/naming functions from kinematics (227)</summary>

Cleaned up the `kinemetics` module by moving `determine_attached_final_state()` to `helicity.decay` and `get_helicity_angle_label()` to `helicity.naming`. Also extracted `get_boost_chain_suffix()` from `get_helicity_angle_label()` in preparation of 212.

</details>

<details>
<summary>Particle LaTeX names are now used in parameters names (228)</summary>

Parameter names that include particle (resonance) names now render more nicely as LaTeX. Compare [old](https://ampform--227.org.readthedocs.build/en/227/usage/amplitude.html#mathematical-formula) rendering with [new](https://ampform--228.org.readthedocs.build/en/228/usage/amplitude.html#mathematical-formula).

**WARNING**: You may have to modify your scripts if they get parameters by name from `HelicityModel.parameter_defaults`!

Other improvements:
- Particle LaTeX names in coefficient names are wrapped in curly braces so that they render correctly if there are also helicities as subscripts.
- Right sidebar (TOC) is unfolded unto the second level.
- `attrs` is rendered as an API link in code snippets as well.

</details>

🐛 Bug fixes

<details>
<summary>AmpForm can only be installed with SymPy v1.8 or v1.9 (247)</summary>

See 248

</details>