bibkey: zaslavsky1998signedgainglossary authors: Thomas Zaslavsky year: 1998 title: “Glossary of Signed and Gain Graphs and Allied Areas” doi: null url: https://people.math.binghamton.edu/zaslav/Bsg/glossary.html claim: “The unsigned incidence matrix is an incidence matrix of the all-negative signature; signed incidence distinguishes equal and opposite endpoint signs.” strata_touched: [] license: citation-only triage: anchor

Signed incidence, switching, and the grid transport interface

Primary locator: the author’s second edition, 16 September 1998, revision a dated 22 September 1998. The HTML was read on 27 September 2026. Relevant entries are oriented incidence matrix, unoriented incidence matrix, incidence matrix of a signed graph, and walk/trail/path. No external PDF was needed for these definitions.

The unsigned matrix has two positive endpoint entries for a link. In the signed convention, a positive edge has opposite endpoint signs and a negative edge has equal endpoint signs. These definitions support the convention JQ=B in docs/develop/theory/RECTANGULAR_GRID_PARITY_TRANSPORT.md, Section 3. The elementary spanning-tree proof of integer saturation is supplied in that theory volume; this source is not represented as a new grid-extremal theorem.

Attribution boundaries

The incidence conventions, switching language, the S4/V4=S3 quotient, and the integer Heisenberg group are classical structures. The present source supplies the first two conventions, not the latter two group proofs. The theory volume supplies self-contained proofs of its classical interfaces and derives its typed-port defect identity, parity-resolved bound, separation bound, and explicit 4-by-6 residual-component counterexample. No claim of worldwide novelty, a full rectangular-grid solution, or Lean verification follows from this note.

Source problem: Library/Combinatorics/sahbi2026subquorum.md. Repository interfaces: the HypercubeSubQuorum, FinitePoisson, and PrimeGoldenBigradedChronologicalSignature Blueprints at dev snapshot ca4ca4d1833db5753487c213af63af7650636842.