- **Breaking change**: new API for pointing computation [319](https://github.com/litebird/litebird_sim/pull/319). Here is a in-depth list of all the breaking changes in this PR:
1. Quaternions describing the orientation of the detectors must now be encoded using a `RotQuaternion` object; plain NumPy arrays are no longer supported.
2. Quaternions are now computed using the function `prepare_pointings()` (low-level) and the method `Simulation.prepare_pointings()` (high-level, you should use this). Pointings are no longer kept in memory until you retrieve them using `Observation.get_pointings()`.
3. Pointings are no longer accessible using the field `pointings` in the `Observation` class. (Not 100% true, see below.) They are computed on the fly by the method `Observation.get_pointings()`.
4. The way pointings are returned differs from how they were stored before. The result of a call to `Observation.get_pointings()` is a 2-element tuple: the first element contains a `(N, 3)` NumPy array containing the colatitude θ, the longitude φ, and the orientation ψ, while the second element is an array of the angles of the HWP. Thus, the orientation angle ψ is now stored together with θ and φ.
5. If you want to pre-compute all the pointings instead of computing them on the fly each time you call `Observation.get_pointings()`, you can use the function `precompute_pointings()` (low-level) and the method `Simulation.precompute_pointings()` (high-level). This initializes a number of fields in each `Observation` object, but they are shaped as described in the previous point, i.e., ψ is kept in the same matrix as θ and φ.
6. The argument `dtype_tod` of the method `Simulation.create_observations` has become `tod_type` for consistency with other similar parameters.
7. The format of the HDF5 files has been slightly changed to let additional information about pointings to be stored.
See the comments in [PR319](https://github.com/litebird/litebird_sim/pull/319) and discussion [#312](https://github.com/litebird/litebird_sim/discussions/312) for more details.
- Add data splits in time and detector space to destriped maps [309](https://github.com/litebird/litebird_sim/pull/309)
- Fix issue [317](https://github.com/litebird/litebird_sim/issues/317)
- Implement a time profiler [308](https://github.com/litebird/litebird_sim/pull/308)