Branchwhose

Branchwhose is a term used in discussions of tree-structured data and graph theory to denote an operator that selects branches (edges or sequences of edges) based on a predicate. In this framework, a branch is a directed connection between nodes that may carry labels or attributes, and branchwhose(P) yields the subset of branches for which the predicate P holds when evaluated on the branch’s properties.

Formally, let T be a rooted tree with node set V and edge set E, where each edge carries attributes such as label, length, or weight. For a predicate P that can be evaluated on a branch b ∈ E (potentially using the attributes of its source and target nodes and the cumulative properties along the branch), branchwhose(P) denotes the set { b ∈ E : P(b) is true }. In some descriptions, a branch is treated as a finite path, so P may reference path length, endpoint characteristics, or intermediate node labels.

Examples include branchwhose(length > 3) to select longer branches, or branchwhose(label = "A" and depth = 2) to pick branches with a specific labeling pattern at a given depth. In query languages for trees, branchwhose is analogous to filtering steps that apply predicates to potential branches during traversal.

Common uses include pruning search spaces in algorithms, querying hierarchical data (such as XML or JSON trees), and formulating expressive path predicates in tree-structured data analyses. The term is not standardized across disciplines and appears mainly in niche discussions of predicate-based branch selection. See also: path, edge, subtree, filter, tree queries.