Slices and views

Slices and views let one AnnNet object support multiple contexts without forcing full graph copies.

What a slice is

A slice is a named graph context attached to the same underlying object. A slice can store:

• vertex memberships
• edge memberships
• slice-level metadata
• edge-level overrides such as slice-specific weights

This makes slices useful for cases such as:

• experimental conditions
• perturbation scenarios
• train and test partitions
• condition-specific subgraphs
• alternative weighting schemes over the same structure

Why slices exist

Without slices, these contexts usually become separate graph copies. That leads to duplicated structure, inconsistent updates, and extra bookkeeping. annnet instead keeps one graph and lets slices describe which parts are active or how specific attributes change in a given context.

Active slice and propagation

The graph keeps one active slice, and many operations use that context by default. When mutating the graph, propagation rules determine whether a change:

• stays local to the current slice,
• is shared with related slices, or
• affects the global structure.

This makes slice handling explicit instead of implicit.

What a view is

A view is a filtered, read-only lens over the graph. It is useful when you want to inspect or compute on a selected part of the graph without materializing a new object.

• G.view(...) creates a filtered view.
• G.subgraph(...) materializes a vertex-induced graph.
• G.edge_subgraph(...) materializes an edge-induced graph.
• G.extract_subgraph(...) combines both filters.

The distinction matters: a view is temporary and lightweight, while a subgraph is a separate graph object.

Relation to layers

Slices are named contexts. Layers are structured coordinates in a multilayer space. If you need explicit multi-aspect graph semantics, use layers. If you need several analysis states over one graph, use slices.