Changelog#

2026.04.1 (current)#

Added#

  • HealpixUNet — PyTorch U-Net on HEALPix geometry with oriented spherical convolutions, BatchNorm, and ReLU; supports regional domains via cell_ids.

  • HealpixViT / HealpixViTSkip — Vision Transformer architectures on HEALPix tokens with optional skip connections.

  • PlanarViT — Vision Transformer on equirectangular grids.

  • alm_loc_optim — optimised local spherical harmonic routines.

  • xarray accessor (foscat.xarray) — integrates FOSCAT statistics with xarray-labelled datasets.

  • MPI-parallel synthesis improvements (isMPI=True).

  • DODIV mode in FoCUS — additional divergence-sensitive wavelet orientations for polarisation analysis.

Changed#

  • PyTorch is now the only active backend. TensorFlow and NumPy backends remain in the source tree for reference but are not maintained and will raise a NotImplementedError at construction time.

  • FoCUS version string updated to "2026.04.1".

  • Default TEMPLATE_PATH is ~/.FOSCAT/data/ (unchanged).

Deprecated#

  • foscat.BkTensorflow — TensorFlow backend. Use PyTorch.

  • foscat.BkNumpy — NumPy backend. Use PyTorch.

  • foscat.UNET — legacy TensorFlow U-Net. Use HealpixUNet.

Earlier versions#

Version history prior to 2026 is tracked in the git log:

git log --oneline --follow src/foscat/FoCUS.py