Module Map

Complete index of FOSCAT modules, classes, and key functions.

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Scattering operators

Module	Entry point	Description
foscat.scat_cov	funct(...)	HEALPix / full-sphere scattering-covariance operator. Returns a FoCUS instance.
foscat.scat_cov2D	funct(...)	2D planar scattering-covariance operator.
foscat.scat_cov1D	funct(...)	1D scattering-covariance operator.
foscat.FoCUS	FoCUS	Core class: wavelet filter construction, GPU dispatch, stencil management.

Synthesis

Module	Entry point	Description
foscat.Synthesis	Synthesis	L-BFGS-B optimisation loop for synthesis / reconstruction.
foscat.Synthesis	Loss	Wraps a user loss function and a scattering operator.

Statistics objects

Module	Class	Description
foscat.scat_cov	scat_cov	Container for S0–S4 coefficient arrays with arithmetic and serialisation.
foscat.scat_cov2D	scat_cov	2D variant of the statistics object.

Neural networks

Module	Class	Description
foscat.healpix_unet_torch	HealpixUNet	PyTorch U-Net on HEALPix geometry with oriented spherical convolutions.
foscat.GCNN	GCNN	Graph-convolutional network using FOSCAT scattering layers.
foscat.CNN	CNN	Flat CNN on HEALPix (simple baseline).
foscat.UNET	UNET	Legacy U-Net (TensorFlow-era, kept for compatibility).
foscat.healpix_vit_torch	HealpixViT	Vision Transformer on HEALPix tokens.
foscat.healpix_vit_skip	HealpixViTSkip	ViT with skip connections.
foscat.planar_vit	PlanarViT	ViT on equirectangular grids.
foscat.unet_2_d_from_healpix_params	—	2D U-Net parameterised from a HEALPix model.

Spherical geometry

Module	Class / function	Description
foscat.SphericalStencil	Convol_torch	Oriented spherical convolution on HEALPix neighbour stencils.
foscat.HOrientedConvol	HOrientedConvol	High-level oriented convolution wrapper.
foscat.SphereDownGeo	SphereDownGeo	Geodesic downsampling between HEALPix resolutions.
foscat.SphereUpGeo	SphereUpGeo	Geodesic upsampling between HEALPix resolutions.
foscat.HealBili	—	Bilinear interpolation between HEALPix resolutions.
foscat.HealSpline	—	Spline interpolation on HEALPix.
foscat.CircSpline	—	Circular spline interpolation.
foscat.Spline1D	—	1D spline interpolation utilities.

Spherical harmonic analysis

Module	Key functions	Description
foscat.alm	map2alm, alm2map, …	Full-sky spherical harmonic decomposition.
foscat.alm_latlon	—	Alm analysis on lat/lon grids.
foscat.alm_loc	—	Local spherical harmonic analysis on regional domains.
foscat.alm_loc_optim	—	Optimised local alm routines.

Backends

Module	Class	Description
foscat.backend	foscat_backend	Abstract base class for all backends.
foscat.BkTorch	BkTorch	Active PyTorch backend (GPU + CPU).
foscat.BkTensorflow	BkTensorflow	Deprecated. TensorFlow backend (not maintained).
foscat.BkNumpy	BkNumpy	Deprecated. NumPy backend — read-only; cannot run Synthesis.

Loss backends (internal)

Module	Description
foscat.loss_backend_torch	Gradient computation via PyTorch autograd.
foscat.loss_backend_tens	Deprecated. Gradient computation via TF GradientTape.

Visualisation

Module	Key functions	Description
foscat.Plot	plot_map, plot_stat, …	Convenience plotting functions (HEALPix Mollweide, statistics curves).

xarray integration

Module	Description
foscat.xarray.accessor	Registers a .foscat accessor on xarray DataArrays.
foscat.xarray.statistics	Statistics computations integrated with xarray labels.
foscat.xarray.parameters	Parameter management for xarray workflows.