flow op• 資料種類:matrix → table
• 呼叫: import fullseye as fs; fs.ledger.graph_physarum_path(lengths, source=0, sink=None, dt=0.1, max_iters=5000, tol=1e-06, frac=0.5)(要直接呼叫實作,import physarum_search; physarum_search.graph_physarum_path(lengths, source=0, sink=None, dt=0.1, max_iters=5000, tol=1e-06, frac=0.5);從台帳取用則 opsgraph.get("graph_physarum_path"))
> 該運算子的說明尚無譯文,以下照原文給出。
Shortest path by the slime mould's tube dynamics (Tero et al. 2010) on a weighted graph.
lengths is a symmetric (n, n) matrix of tube lengths (0 = no tube, diagonal 0). A unit flow is pushed from source to sink (default n - 1) through tubes of conductance D_e; the pressures solve the weighted Laplacian (Kirchhoff), the flow in a tube is Q_e = D_e (p_u - p_v) / L_e, and each tube adapts dD_e/dt = |Q_e| - D_e (explicit Euler, step dt). Bonifaci, Mehlhorn and Varma (2012) prove that with a unique shortest path the conductances converge to its indicator: D_e -> 1 on it, 0 off it. The path is read by following, from the source, the tube that carries the most flow out of each node (a potential flow has no cycle); it must be at least frac of the thickest tube all along, else the run is refused as not converged.
Returns conductance and flow ((n, n) matrices, flow antisymmetric), path (node indices source → sink), path_length (sum of the tube lengths along it), flow_length = sum |Q_e| L_e (the length of the unit flow; it is >= path_length for every unit flow and equal only when all flow rides shortest paths), iters, converged (max |dD| fell below tol), history (max |dD| per iteration).
Raises ValueError: matrix not square / symmetric / finite / non-negative, self-loops; bad node indices or source == sink; sink unreachable; dt outside (0, 1]; no path survived the threshold (not converged).
• 範例資料目錄(下載 URL / 授權) —— 2-D 用 skimage.data(BSD/公有領域)加合成圖,3-D 給出真實資料源(Stanford/PDS 等)的下載 URL。
• 運算子來歷與參考文獻 —— 該運算子族所依據的研究/方法出處。
• 演算法的正典(作者、年份)與用途見上面的族使用指南。
• poc_physarum_maze — py -3.11 examples/poc_physarum_maze.py
table 作為輸入)graph_edge_consensus · graph_core_persistence · tree_morphometry · tree_sholl · tree_run_length
flow)physarum_route · graph_physarum_transport · physarum_transport_image
*Provenance: physarum_search.py — GRAPH 運算子登記表。本條目由 tools/opdocs.py md 自動產生(請勿手動編輯)。*
© 2026 Kazufumi Furuse — Fullseye operator documentation. Licensed under Apache-2.0.