Struct SphericalChannelsResidual 

pub struct SphericalChannelsResidual {
    basis: Basis,
    ks: [Complex; 2],
    q: Vec<[f64; 2]>,
    polarizations: Vec<u8>,
    area: f64,
    helicity: bool,
    fixed_q: bool,
}

What spherical_channels saves for its pullback: its inputs alone.

The pullback recomputes each channel with its derivatives with respect to the position, the wavenumber, the transverse wavevector and the area.

The pullback adds the per-column position, wavenumber and area gradients in chunks of consecutive columns fixed by the column count, and the chunk sums in chunk order (numerics::parallel::try_fold_ordered), so the thread count does not change them. Each transverse-wavevector gradient belongs to one column, which writes it in place.

Fields

basis: Basis

ks: [Complex; 2]

q: Vec<[f64; 2]>

polarizations: Vec<u8>

area: f64

helicity: bool

fixed_q: bool

Implementations

impl SphericalChannelsResidual

pub fn state_size( multipoles: usize, positions: usize, channels: usize, ) -> Result<usize>

Bytes of saved derivative state for the fixed basis and channel counts.

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

The shape of the channel matrix: four rows per multipole, one column per plane mode.

pub fn validate_tangent( &self, positions: &[[f64; 3]], ks: [Complex; 2], q: &[[f64; 2]], measure: f64, ) -> Result<()>

Check finite input tangents and their position and plane counts.

pub fn pushforward( &self, positions: &[[f64; 3]], ks: [Complex; 2], q: &[[f64; 2]], measure: f64, ) -> Result<DMatrix<Complex>>

Directional derivative of the channel matrix. Tangents have the same shapes and order as the pullback outputs; q is held fixed with fixed_q. A zero transverse tangent also permits other input directions at normal incidence.

pub fn pullback(&self, cotangent: &DMatrix<Complex>) -> Result<ChannelGradient>

Gradients of the positions, the two medium wavenumbers, the transverse wavevectors (zero with fixed_q) and the area, for a cotangent of the channel matrix’s shape. Both families traverse columns, sides and multipoles in the same order.

Trait Implementations

impl Clone for SphericalChannelsResidual

fn clone(&self) -> SphericalChannelsResidual

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SphericalChannelsResidual

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

Formats the value using the given formatter.

impl SavedState for SphericalChannelsResidual

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.