Ampform

See all documentation for this version [here](https://ampform.rtfd.io/en/0.10.5).

_Final release before [v0.11.0](https://github.com/ComPWA/ampform/milestone/16)._

🐛 Bug fixes

<details>
<summary>Implemented deep argument in doit instead of the new method (114)</summary>

Fixes a small bug that was introduced by the new function `create_expression`, which was introduced in 113. That function allowed handling the `deep` argument in `doit`, so that expressions containing a `BlattWeisskopfSquared` can be called with `doit(deep=False)`. The fix was faulty though; this PR is the correct implementation.

</details>

<details>
<summary>Slider descriptions now use HTML math mode (cafddea)</summary>

Math mode in ipywidgets doesn't render well when using LaTeX dollar signs for math mode. HTML math mode `\(...\)` works well both in Jupyter notebook and in HTML.

</details>

See all documentation for this version [here](https://ampform.rtfd.io/en/0.10.4).

💡 New features

<details>
<summary>Improved symplot.SliderKwargs class (109)</summary>

Some minor changes that improve usage of `symplot`, but don't affect interface. Required for https://github.com/ComPWA/compwa-org/pull/37.

- [x] Set step size (not number of steps) if `n_steps` is `float` in `set_ranges`
- [x] Un-hide `_sliders` and `_arg_to_symbol` attributes of `SliderKwargs`

</details>

<details>
<summary>Implemented symplot.substitute_indexed_symbols() function (111)</summary>

Implementation of [[TR-008] `Indexed` free symbols](https://compwa-org.readthedocs.io/en/stable/report/008.html)

</details>

<details>
<summary>Implemented symplot.partial_doit() function (112)</summary>

Helper function for https://github.com/ComPWA/compwa-org/pull/37

</details>


⚠️ Interface

<details>
<summary>Remove angular momentum projection from formulate_clebsch_gordan_coefficients (102)</summary>

See https://github.com/ComPWA/ampform/pull/100#issuecomment-886250406

</details>


🐛 Bug fixes

<details>
<summary>DOT is now wrapped in a figure (106)</summary>

Fixes 105

Bit of a clumsy solution, using the `figure` directive, but I don't see another way around it...

</details>

<details>
<summary>Remove verify_signature function (110)</summary>

This check makes the framework less flexible and the additional code is not worth the 'friendly' exception. It is required for https://github.com/ComPWA/compwa-org/pull/37, where a special class `PhaseSpaceFactor` is inserted into `coupled_width`.

</details>

<details>
<summary>UnevaluatedExpr can now be instantiated with a doit argument (113)</summary>

Previously, there something like `BlattWeisskopfSquared(...).doit(deep=False)` would crash. This fixes that behavior.

See also https://github.com/ComPWA/compwa-org/pull/37

</details>



📝 Documentation

<details>
<summary>Extended docstrings of helicity and kinematics modules (100)</summary>

Added several examples that explain the implementations in the `helicity` and `kinematics` modules.

A preview of the API can be viewed here:
https://ampform--100.org.readthedocs.build/en/100/api/ampform.html

</details>

<details>
<summary>Widen cell output where needed (103)</summary>

Widen cells where their input and/or output is so wide that a horizontal scrollbar appears. This can be done with the `full-width` tag:
https://sphinx-book-theme.readthedocs.io/en/latest/layout.html#full-width-content

For instance:


versus ([v0.10.3](https://ampform.readthedocs.io/en/0.10.3/usage/amplitude.html#build-sympy-expression)):

</details>


<details>
<summary>Documentation pages are wider now (104)</summary>

Ignored panel css to increase main content width. Otherwise the main content ends up being weirdly small. See:

- https://github.com/executablebooks/sphinx-book-theme/blob/547cc95674623345124d9bbea9e15e5b5fa34d0e/docs/conf.py#L62
- https://sphinx-panels.readthedocs.io/en/latest/index.html?highlight=panels_add_bootstrap_css#sphinx-configuration


Old:


New:

Many thanks to ianhi!


</details>


🖱️ Developer Experience

<details>
<summary>Switched to pre-commit.ci where possible (107)</summary>

See ComPWA/qrules87

</details>

See all documentation for this version [here](https://ampform.rtfd.io/en/0.10.3).

💡 New features

<details>
<summary>Define breakup_momentum function (97)</summary>

It makes more sense to use `breakup_momentum` as an argument to `phsp_factor` in [`relativistic_breit_wigner_with_ff`](https://ampform.readthedocs.io/en/0.10.2/api/ampform.dynamics.html#ampform.dynamics.relativistic_breit_wigner) etc than [`breakup_momentum_squard`](https://ampform.readthedocs.io/en/0.10.2/api/ampform.dynamics.html#ampform.dynamics.breakup_momentum_squared).

</details>


⚠️ Interface

<details>
<summary>Removed sympy.Piecewise from rrelativistic_breit_wigner_with_ff (98)</summary>

The function [`relativistic_breit_wigner_with_ff`](https://ampform.readthedocs.io/en/0.10.2/api/ampform.dynamics.html#ampform.dynamics.relativistic_breit_wigner_with_ff) now produces
<img src="https://user-images.githubusercontent.com/29308176/125973679-8f97ae5d-37f1-4ef0-a018-bdc919b2e4cb.png" width=500>
instead of
<img src="https://user-images.githubusercontent.com/29308176/125973965-008c5036-93a0-43f5-a1a8-cc4a8d4943b0.png" width=700>
The latter was mistakenly introduced because of a wrong parameterization in [`phase_space_factor_analytic`](https://ampform.readthedocs.io/en/0.10.2/api/ampform.dynamics.html#ampform.dynamics.phase_space_factor_analytic) (this one is valid only for equal masses).

</details>

📝 Documentation

<details>
<summary>Colorized extracted amplitudes in formalism notebook (0f913d6)</summary>


</details>

<details>
<summary>Added links to ComPWA organization (a6dd74d)</summary>


</details>

🖱️ Developer Experience

<details>

<summary>Allow 📖 Physics issue label (56cb749)</summary>


</details>

See all documentation for this version [here](https://ampform.rtfd.io/en/0.10.2).

📝 Documentation

<details>
<summary>Added helicity-vs-canonical basis comparison (95)</summary>

Added a notebook that describes the difference between the **helicity basis** and **canonical basis** in the helicity formalism.

</details>

🐛 Bug fixes

<details>
<summary>Required numpy version is limited to v1.20 (91)</summary>

Since [NumPy v1.21](https://github.com/numpy/numpy/releases/tag/v1.21.0) it is required to explicitly define `__array_ufunc__`, both for static typing as for running the code. With the current set-up, `__array_ufunc__` is too problematic. Better solution would be #92.

</details>

See all documentation for this version [here](https://ampform.rtfd.io/en/0.10.1).

💡 New features

<details>
<summary>Implemented HelicityModel.sum_components (90)</summary>

Import [`tensorwaves.physics.add_components`](https://tensorwaves.readthedocs.io/en/0.2.8/api/tensorwaves.physics.html#tensorwaves.physics.add_components).

Note that this allows removing the [`tensorwaves.physics`](https://tensorwaves.readthedocs.io/en/0.2.8/api/tensorwaves.physics.html) module.

</details>

See all documentation for this version [here](https://ampform.rtfd.io/en/0.9.5).

⚠️ Interface

<details>
<summary>AmpForm interface and implementation has been adapted to the new QRules interface (84)</summary>

Adapts the AmpForm interface and implementation to [QRules v0.9.0](https://github.com/ComPWA/qrules/releases/tag/0.9.0).

Naming has been changed accordingly, most notably that graphs become transitions, edges becomes states, nodes become interactions. Some related interface changes:

- AmpForm's own `ReactionInfo` (under `kinematics`) and `State` (under `helicity`) have been removed
- `TwoBodyKinematicVariableSet`:
- `in_edge_inv_mass` -> `incoming_state_mass`
- `out_edge_inv_mass1` -> `outgoing_state_mass1`
- `out_edge_inv_mass2` -> `outgoing_state_mass2`
- There are now also an instance check on its constructor.

</details>

<details>
<summary>AmpForm's helicity module has been split (87)</summary>

Split up the `helicity` module.

Major change: the `generate()` method is now called `formulate()` (97e9ce2)

Related to 61


</details>

<details>
<summary>HelicityModel.generate() has been renamed to HelicityModel.formulate() (87)</summary>

All methods and functions that produce `sympy.Expr`s are now named 'formulate' instead of 'generate'.


</details>

<details>
<summary>Coefficient names have been changed (80)</summary>

**This changes the sum of amplitudes in some cases!**

Fixes 73

New notation:


For comparison, there's also 32bb1b6, which also includes helicity, but which results in 8 unique coefficient names:




</details>




🔨 Internal maintenance

<details>
<summary>Test fixtures are now parametrized (86)</summary>

Some improvements to the test set-up.

</details>


📝 Documentation

<details>
<summary>Links to expertsystem replaced with internal links (82)</summary>

Some links in the `expertsystem`, because [intersphinx](https://www.sphinx-doc.org/en/master/usage/extensions/intersphinx.html) is a bit too eager.

</details>

<details>
<summary>Intersphinx links can now pinned to specific versions of external API pages (83)</summary>

</details>

<details>
<summary>Added explanation for how to substitute parameters (88)</summary>

First step towards 5. Adds a new page that shows some SymPy tricks to modify the `HelicityModel`.

</details>

<details>
<summary>Added explanation of how to couple parameters (89)</summary>

Closes 5

</details>