Module expansion 

Spherical expansion matrices between two bases and over a lattice, with analytic pullbacks. Each pair of a destination and a source position forms one block, and blocks with the same modes share one TranslationPlan.

Upstream: the treams.Expand and treams.ExpandLattice operators between spherical bases.

Modules

lattice_state 🔒

Saved periodic geometry and static angular-plan inputs, without Ewald reevaluation. treams-rs extension.

Structs

Block 🔒

The modes of one destination position against those of one source position.

ExpansionResidual

What expansion saves for its pullback: the bases, the wavenumbers, the radial kind and every block with its translation plan. The pullback recomputes the derivative tables per block.

LatticeExpansionFromTableResidual

What lattice_expansion_from_table saves for its pullback: the sparse angular weights, never the table values. The pullback runs in block order and gives the same result every run.

LatticeExpansionResidual

What lattice_expansion saves for its pullback: the bases, the wavenumbers, the lattice, the split and the blocks, whose angular plans every position pair shares.

Constants

BATCH 🔒

Entries of the block values evaluated at once, bounding the transient memory of the parallel assembly (16 MiB, twice that for two wavenumbers).

Functions

assemble 🔒

Evaluate the blocks in parallel, in batches of at most batch entries or of one larger block, and scatter them in order. A missing second polarization shares the first; two missing polarizations skip the block. The evaluator also receives the worker budget of the current batch for nested lattice evaluations.

batch_count 🔒

Blocks fitting the scratch-entry budget, or one block if it alone exceeds it.

blocks 🔒

expansion

Construct a regular or singular spherical expansion matrix, which maps source coefficients to destination coefficients.

expansion_block 🔒

The regular or singular translation of one block, or None for the singular self block: outgoing waves do not couple a position to itself.

lattice_expansion

Periodic outgoing-to-regular spherical coupling, including nonzero lattice images of self blocks.

lattice_expansion_from_table

The lattice expansion matrix from a table of lattice sums, a linear map of the table.

validate_expansion 🔒

Validate both bases and the medium of an expansion.