NEST-Compatible Spatial Networks

Spatially-structured network primitives compatible with the NEST simulator nest.spatial API. These build layers of nodes embedded in 2-D or 3-D space, define distance-dependent connection kernels and masks, and provide tools to inspect and visualize the resulting connectivity.

Layers & Positions

Construct populations whose nodes carry spatial coordinates.

spatial.Layer	A set of node positions in 2-D or 3-D space.
spatial.grid	Build a regular cell-centered lattice (NEST nest.spatial.grid).
spatial.free	Build a free-position layer (NEST nest.spatial.free).
spatial.pos	Exposes .x/.y/.z building a given per-axis expression class (NEST pos etc.).
spatial.source_pos	Exposes .x/.y/.z building a given per-axis expression class (NEST pos etc.).
spatial.target_pos	Exposes .x/.y/.z building a given per-axis expression class (NEST pos etc.).

Distance & Displacement

Compute spatial relationships between source and target nodes.

spatial.displacement	Pairwise displacement post - pre.
spatial.pairwise_distance	Pairwise Euclidean distance.
spatial.Distance	Pairwise Euclidean distance between two layers (NEST Distance).

Connection Kernels

Distance-dependent connection-probability profiles.

spatial.gaussian	Gaussian distance-dependent connection probability.
spatial.exponential	Exponential distance-dependent connection probability.
spatial.gamma	Gamma distance-dependent connection probability.
spatial.gabor	Rectified-Gabor connection probability on the (x, y) displacements (NEST gabor).
spatial.gaussian2D	Bivariate-Gaussian connection probability on the (x, y) displacements (NEST gaussian2D).

Masks

Spatial regions that restrict the set of candidate targets.

spatial.circular	Circular mask (2-D): target within radius of source.
spatial.spherical	Spherical mask (3-D): target within radius of source (same cutoff as circular).
spatial.box	Box mask (2-D/3-D): target displacement within [lower_left, upper_right].
spatial.rectangular	Rectangular mask (2-D): target displacement within [lower_left, upper_right].
spatial.doughnut	Doughnut (annulus) mask (2-D): inner_radius < d <= outer_radius.
spatial.elliptical	Elliptical mask (2-D): displacement inside a rotated ellipse (NEST elliptical).
spatial.ellipsoidal	Ellipsoidal mask (3-D): displacement inside a rotated ellipsoid (NEST ellipsoidal).

Spatial Connection Rules

Distance-dependent pairwise-Bernoulli connectivity.

spatial.SpatialConnRule	Spatially-resolved pairwise-Bernoulli rule: p(d) within an optional mask.
spatial.spatial_pairwise_bernoulli	Distance-dependent pairwise-Bernoulli connection rule (NEST spatial pairwise_bernoulli).

Node Selection & Introspection

Query nodes by position or mask and dump the resulting layer connectivity.

spatial.center_element	Local index of the node nearest the layer centroid (NEST FindCenterElement).
spatial.nearest_element	Local index of the node nearest each query location (NEST FindNearestElement).
spatial.select_nodes_by_mask	Local indices of the nodes lying inside mask anchored at anchor (NEST SelectNodesByMask).
spatial.target_nodes	Realized target indices of each source node (NEST GetTargetNodes).
spatial.target_positions	Coordinates of each source node's realized targets (NEST GetTargetPositions).
spatial.dump_layer_nodes	Write each node's local index + coordinates to outname (NEST DumpLayerNodes).
spatial.dump_layer_connections	Write each realized edge's endpoints, weight, delay and displacement (NEST DumpLayerConnections).

Visualization

Plot layers, connection targets/sources, and probability kernels.

spatial.plot_layer	Scatter a layer's node positions (NEST PlotLayer).
spatial.plot_targets	Highlight one source node's realized targets (NEST PlotTargets).
spatial.plot_sources	Highlight one target node's realized sources (NEST PlotSources).
spatial.plot_probability_parameter	Heatmap of a connection kernel p(d) over a 2-D field (NEST PlotProbabilityParameter).