Struct Square4 

pub struct Square4 { /* private fields */ }

A two-dimensional square grid with 4-connected neighbourhood.

Each cell has coordinate [row, col] where 0 <= row < rows and 0 <= col < cols. Neighbours are the four cardinal directions (north, south, east, west). Distance is Manhattan (L1).

Boundary handling is controlled by EdgeBehavior:

• Absorb: edge cells have fewer neighbors (corners have 2, edges have 3)
• Clamp: edge cells self-loop on the boundary axis
• Wrap: periodic boundary (torus topology)

Implementations

impl Square4

pub const MAX_DIM: u32

Maximum dimension size: coordinates use i32, so each axis must fit.

pub fn new(rows: u32, cols: u32, edge: EdgeBehavior) -> Result<Self, SpaceError>

Create a new 2D grid with rows * cols cells and the given edge behavior.

Returns Err(SpaceError::EmptySpace) if either dimension is 0, or Err(SpaceError::DimensionTooLarge) if either exceeds i32::MAX.

Examples

use murk_space::{Square4, EdgeBehavior, Space};

let grid = Square4::new(16, 16, EdgeBehavior::Absorb).unwrap();
assert_eq!(grid.cell_count(), 256);
assert_eq!(grid.ndim(), 2);

// Neighbors of corner cell [0, 0] with Absorb: only 2 neighbors.
let coord = vec![0i32, 0].into();
assert_eq!(grid.neighbours(&coord).len(), 2);

pub fn rows(&self) -> u32

Number of rows.

pub fn cols(&self) -> u32

Number of columns.

pub fn is_empty(&self) -> bool

Always returns false — construction rejects empty grids.

pub fn edge_behavior(&self) -> EdgeBehavior

Edge behavior.

Trait Implementations

impl Clone for Square4

fn clone(&self) -> Square4

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Square4

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

Formats the value using the given formatter.

impl Space for Square4

fn ndim(&self) -> usize

Number of spatial dimensions.

fn cell_count(&self) -> usize

Total number of cells in the space.

fn neighbours(&self, coord: &Coord) -> SmallVec<[Coord; 8]>

Enumerate the neighbors of a cell.

fn max_neighbour_degree(&self) -> usize

Maximum neighbor-list length over all cells in this space.

fn distance(&self, a: &Coord, b: &Coord) -> f64

Graph-geodesic distance between two cells.

fn compile_region(&self, spec: &RegionSpec) -> Result<RegionPlan, SpaceError>

Compile a region specification into a plan for O(1) lookups.

fn canonical_ordering(&self) -> Vec<Coord>

All cells in deterministic canonical order.

fn canonical_rank(&self, coord: &Coord) -> Option<usize>

Position of a coordinate in the canonical ordering.

fn canonical_rank_slice(&self, coord: &[i32]) -> Option<usize>

Position of a coordinate slice in the canonical ordering.

fn instance_id(&self) -> SpaceInstanceId

Unique instance identifier for this space object.

fn topology_eq(&self, other: &dyn Space) -> bool

Returns true if self and other are topologically equivalent: same concrete type and identical behavioral parameters.

fn iter_region<'a>( &'a self, plan: &'a RegionPlan, ) -> Box<dyn Iterator<Item = Coord> + 'a>

Iterate over the cells in a compiled region.

fn map_coord_to_tensor_index( &self, coord: &Coord, plan: &RegionPlan, ) -> Option<usize>

Map a coordinate to its flat tensor index within a compiled region.