graph_kcore — GRAPH core op

• Data kinds: matrix → table

• Call: import fullseye as fs; fs.ledger.graph_kcore(adj, mode='total', weighted=False) (implementation को सीधे call करना हो तो import graphinv; graphinv.graph_kcore(adj, mode='total', weighted=False), registry से लेना हो तो opsgraph.get("graph_kcore"))

उपयोग

wiring matrix का k-core (या weighted s-core) decomposition — हर node का core index।

> नीचे का विस्तृत विवरण मूल text में है — सारांश और headings का अनुवाद हो चुका है।

A k-core is the maximal subgraph in which every node has degree at least k (Seidman 1983); a node's core index is the largest k of a core it belongs to. mode picks the degree: "in" (inputs a node receives), "out", "total" (in + out; a reciprocal pair counts twice, as in conngraph.graph_rich_club) or "undirected" (an edge in either direction counts once — this is what networkx.core_number computes on the symmetrised graph). With weighted=True the degree is the strength (sum of weights, e.g. synapse counts) and the result is the s-core of Eidsaa & Almaas 2013: the index is the running maximum of the minimum strength during peeling, so it is a real number with the units of the weights. Self-loops are dropped.

Returns a dict: core (n,) — the index per node (int for k-core, float for s-core); kmax — the innermost index; inner (n,) bool — nodes of the innermost core; n_inner; levels — the distinct indices in increasing order and counts — how many nodes have each (sum(counts) == n); mode; weighted.

Identities (the tests): a complete graph on n nodes has every index n−1; a tree 1; a cycle 2; undirected agrees with networkx.core_number on random graphs; the s-core of a 0/1 matrix equals the k-core; multiplying every weight by c multiplies every s-core index by c; the innermost core is never empty and every one of its nodes has at least kmax (weighted: strength) inside the core.

Raises ValueError: as graph_degree_summary (non-square, negative, non-finite, string / bool / complex / masked input); mode not one of in / out / total / undirected.

संदर्भ (sample data, साहित्य)

• Sample data catalog (DL URL / license) — 2-D के लिए skimage.data (BSD/public) + synthetic, 3-D के लिए real data sources (Stanford/PDS आदि) के DL URL।

• Operators का स्रोत और संदर्भ — इस op family के मूल research/methods के स्रोत।

• Algorithm का मानक स्रोत (लेखक, वर्ष) और उपयोग ऊपर की family usage guide में दिए गए हैं।

चलाए जा सकने वाले उदाहरण (verified samples जो सच में यह op call करते हैं)

• poc_worm_core_persists — py -3.11 examples/poc_worm_core_persists.py

वे अगले ops जिनसे type जुड़ता है (table को input के रूप में लेते हैं)

graph_edge_consensus · graph_core_persistence · tree_morphometry · tree_sholl · tree_run_length

इसी category के (core)

graph_rich_club_curve


*Provenance: graphinv.py — GRAPH operator registry. यह per-op note tools/opdocs.py md से अपने-आप generate होता है (हाथ से edit न करें)।*

© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.