fig2

Figure 2. Original graph reproduction and representation dependence. (A and B) The exact original nine-node graphs with identical node positions. MCLV, the original ipsilateral SDC and the inter-perforator link are labeled in (A). In (B), thick ochre dashed edges denote the numerical weight 0.03; the three explicitly named linking edges are absent. These mixed graphs are retained as connectivity benchmarks, not hydraulic tissue models; (C and D) Replacing each edge g by k serial edges kg preserves its resistance while changing raw λ₂. Kron reduction retaining the original nine nodes recovers the original connectivity value. This tests subdivision invariance, not the accuracy of anatomical coarse-graining. λ₂: Second-smallest eigenvalue of the weighted Laplacian; SDC: superficial-to-deep connection; DIEA/DIEV: deep inferior epigastric artery/vein; SIEV: superficial inferior epigastric vein; MCLV: midline-crossing linking vein.