Struct IlluminateResidual 

pub struct IlluminateResidual {
    lower: [StoredBlock; 4],
    upper: [StoredBlock; 4],
    incoming: [DMatrix<Complex>; 2],
    solve: InternalSolve,
    down: DMatrix<Complex>,
}

What illuminate saves for its pullback: copies of the blocks of both stacks, the incoming fields, the internal-field solve and the downgoing internal fields.

The solve keeps a dense LU factorization unless it solved iteratively. The iterative (Krylov) solve needs at least 512 rows, at most 8 illumination columns, an internal operator that is a proven contraction, and convergence within 16 steps.

Fields

lower: [StoredBlock; 4]

upper: [StoredBlock; 4]

incoming: [DMatrix<Complex>; 2]

solve: InternalSolve

down: DMatrix<Complex>

Implementations

impl IlluminateResidual

pub fn state_size(n: usize, columns: usize) -> Result<usize>

Byte count for saved illumination state with mode and illumination counts.

impl IlluminateResidual

pub fn shape(&self) -> (usize, usize)

Mode and independent-illumination counts.

pub fn pushforward( &self, lower: &Blocks, upper: &Blocks, incoming: &[DMatrix<Complex>; 2], ) -> Result<[DMatrix<Complex>; 4]>

Propagate stack and incident-field tangents through the recorded solve. Products remain mode-by-illumination arrays for a thin illumination batch.

pub fn pullback( &self, cotangent: &[DMatrix<Complex>; 4], ) -> Result<IlluminateGradient>

Return lower/upper S matrices and incoming up/down amplitude cotangents.

Trait Implementations

impl Debug for IlluminateResidual

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl SavedState for IlluminateResidual

fn save_state(&self) -> Result<Vec<u8>>

Copy the saved numerical state into its fixed byte layout.

fn from_state(bytes: &[u8]) -> Result<Self>

Restore numerical state from bytes produced by this extension.