S2fft

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What's Changed

📦 Dependency updates
* Bump pypa/cibuildwheel from 2.23.1 to 2.23.2 by dependabot in https://github.com/astro-informatics/s2fft/pull/286
* Bump actions/setup-python from 2 to 5 by dependabot in https://github.com/astro-informatics/s2fft/pull/289
* Bump JamesIves/github-pages-deploy-action from 4.1.5 to 4.7.3 by dependabot in https://github.com/astro-informatics/s2fft/pull/288
* Bump actions/checkout from 2.3.1 to 4.2.2 by dependabot in https://github.com/astro-informatics/s2fft/pull/287
* Bump codecov/codecov-action from 3 to 5 by dependabot in https://github.com/astro-informatics/s2fft/pull/285

New Contributors
* dependabot made their first contribution in https://github.com/astro-informatics/s2fft/pull/286

**Full Changelog**: https://github.com/astro-informatics/s2fft/compare/v1.2.1...v1.2.2

<!-- Release notes generated using configuration in .github/release.yml at main -->

What's Changed

✨ New features
* Make pyssht and healpy optional dependencies by matt-graham in https://github.com/astro-informatics/s2fft/pull/267
📖 Documentation improvements
* Minor fixes in the documentation by PhilippMisofCH in https://github.com/astro-informatics/s2fft/pull/265
* De-duplicate README content and update installation instructions by matt-graham in https://github.com/astro-informatics/s2fft/pull/274
🛠 Other changes
* Allow changing orientation of benchmark plots by matt-graham in https://github.com/astro-informatics/s2fft/pull/272

New Contributors
* PhilippMisofCH made their first contribution in https://github.com/astro-informatics/s2fft/pull/265

**Full Changelog**: https://github.com/astro-informatics/s2fft/compare/v1.2.0...v1.2.1

<!-- Release notes generated using configuration in .github/release.yml at main -->

What's Changed
✨ New features
* Performance improvements by CosmoMatt in https://github.com/astro-informatics/s2fft/pull/200
* Custom HEALPix FFT primitive when running on GPU by ASKabalan in https://github.com/astro-informatics/s2fft/pull/204
* Add stable high-spin transforms (precompute, standard) by CosmoMatt in https://github.com/astro-informatics/s2fft/pull/230
* Add stable forward/inverse memory efficient Wigner transforms by CosmoMatt in https://github.com/astro-informatics/s2fft/pull/238
* Add custom collective transforms by CosmoMatt in https://github.com/astro-informatics/s2fft/pull/239
* Avoid loops in `s2fft.sampling.reindex` functions to reduce compile and run times by matt-graham in https://github.com/astro-informatics/s2fft/pull/245
* Correct `healpix_forward` derivatives and add support for forward and higher order autodiff by matt-graham in https://github.com/astro-informatics/s2fft/pull/244
* Improvements to benchmarking system by matt-graham in https://github.com/astro-informatics/s2fft/pull/248
* Iterative refinement support for JAX and NumPy forward (spherical) transform implementations by matt-graham in https://github.com/astro-informatics/s2fft/pull/241
* Vectorize signal generator functions by matt-graham in https://github.com/astro-informatics/s2fft/pull/252
📖 Documentation improvements
* Feature/notebook plots by CosmoMatt in https://github.com/astro-informatics/s2fft/pull/202
* Execute main spherical transform notebook by jasonmcewen in https://github.com/astro-informatics/s2fft/pull/203
* Add low precision warning to docstring of inverse Wigner function by ElisR in https://github.com/astro-informatics/s2fft/pull/220
* Update citation details in docs and add CITATION.cff file by matt-graham in https://github.com/astro-informatics/s2fft/pull/236
* Indicate cubic memory overhead in `generate_precomputes` docstring by matt-graham in https://github.com/astro-informatics/s2fft/pull/257
🐛 Bug fixes
* Fix pass through of arguments to `generate_precomputes` in NumPy forward spherical transform by matt-graham in https://github.com/astro-informatics/s2fft/pull/256
* Fix failing `test_transform_forward_healpix_iter` test by matt-graham in https://github.com/astro-informatics/s2fft/pull/258
🛠 Other changes
* Switching to `pyproject.toml` for specifying package metadata by matt-graham in https://github.com/astro-informatics/s2fft/pull/173
* Updates to custom CUDA HEALPix FFT primitive by matt-graham in https://github.com/astro-informatics/s2fft/pull/231

New Contributors
* ElisR made their first contribution in https://github.com/astro-informatics/s2fft/pull/220
* ASKabalan made their first contribution in https://github.com/astro-informatics/s2fft/pull/204

**Full Changelog**: https://github.com/astro-informatics/s2fft/compare/v1.1.0...v1.2.0

This minor release of `S2FFT` aims to increase the accessibility of differentiable harmonic transforms to users without easy access to GPU compute resources. We provide custom JAX frontends for existing CPU bound C/C++ spherical harmonic libraries, at this point we capture the functionality of [`SSHT`](https://astro-informatics.github.io/ssht/) and [`HEALPix`](https://healpy.readthedocs.io/en/latest/) though in principle any spherical harmonics could easily be integrated.

> [!tip]
> For details on this approach see the original derivation in section 5.3.1 and 5.3.2 of [Price & McEwen 2023](https://arxiv.org/pdf/2311.14670.pdf).

Main changelog:

- JAX frontend support for HEALPix C++ library
- JAX frontend support for SSHT C library
- Reverse mode gradients for above validated against finite difference

Incremental version of `S2FFT` which adds support for:

- `PyTorch` precompute transforms
- Gauss-Legendre sampling schemes
- JAX harmonic space rotation functions
- JAX Risbo recursions

This version also implements some changes to reduce the compile time of HEALPix Fast Fourier transforms, though this issues is yet to be fully solved.

This is a relatively small patch which attempts to **mitigate the compile time of HEALPix transforms**. Though this is unlikely to have solved the overall scaling of the compile time, it has reduced the time by a factor of ~4 which should help.