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.