o ˷eW@s0dZddlmZddgZd ddZd ddZdS) aYRoutines to find the boundary of a set of nodes. An edge boundary is a set of edges, each of which has exactly one endpoint in a given set of nodes (or, in the case of directed graphs, the set of edges whose source node is in the set). A node boundary of a set *S* of nodes is the set of (out-)neighbors of nodes in *S* that are outside *S*. )chain edge_boundary node_boundaryNFcstfdd|Drj|||d}nj||d}|dur,fdd|DSt|fdd|DS) amReturns the edge boundary of `nbunch1`. The *edge boundary* of a set *S* with respect to a set *T* is the set of edges (*u*, *v*) such that *u* is in *S* and *v* is in *T*. If *T* is not specified, it is assumed to be the set of all nodes not in *S*. Parameters ---------- G : NetworkX graph nbunch1 : iterable Iterable of nodes in the graph representing the set of nodes whose edge boundary will be returned. (This is the set *S* from the definition above.) nbunch2 : iterable Iterable of nodes representing the target (or "exterior") set of nodes. (This is the set *T* from the definition above.) If not specified, this is assumed to be the set of all nodes in `G` not in `nbunch1`. keys : bool This parameter has the same meaning as in :meth:`MultiGraph.edges`. data : bool or object This parameter has the same meaning as in :meth:`MultiGraph.edges`. default : object This parameter has the same meaning as in :meth:`MultiGraph.edges`. Returns ------- iterator An iterator over the edges in the boundary of `nbunch1` with respect to `nbunch2`. If `keys`, `data`, or `default` are specified and `G` is a multigraph, then edges are returned with keys and/or data, as in :meth:`MultiGraph.edges`. Notes ----- Any element of `nbunch` that is not in the graph `G` will be ignored. `nbunch1` and `nbunch2` are usually meant to be disjoint, but in the interest of speed and generality, that is not required here. ch|]}|vr|qSr.0nGrS/var/www/ideatree/venv/lib/python3.10/site-packages/networkx/algorithms/boundary.py Dz edge_boundary..)datakeysdefault)rrNc3s,|]}|dv|dvAr|VqdSrNrre)nset1rr Ss*z edge_boundary..c3sD|]}|dvr|dvs|dvr|dvr|VqdSrrr)rnset2rr rUs0) is_multigraphedgesset)r nbunch1nbunch2rrrrr)r rrr rs4 csJfdd|D}ttfdd|D|}|dur#|t|M}|S)a|Returns the node boundary of `nbunch1`. The *node boundary* of a set *S* with respect to a set *T* is the set of nodes *v* in *T* such that for some *u* in *S*, there is an edge joining *u* to *v*. If *T* is not specified, it is assumed to be the set of all nodes not in *S*. Parameters ---------- G : NetworkX graph nbunch1 : iterable Iterable of nodes in the graph representing the set of nodes whose node boundary will be returned. (This is the set *S* from the definition above.) nbunch2 : iterable Iterable of nodes representing the target (or "exterior") set of nodes. (This is the set *T* from the definition above.) If not specified, this is assumed to be the set of all nodes in `G` not in `nbunch1`. Returns ------- set The node boundary of `nbunch1` with respect to `nbunch2`. Notes ----- Any element of `nbunch` that is not in the graph `G` will be ignored. `nbunch1` and `nbunch2` are usually meant to be disjoint, but in the interest of speed and generality, that is not required here. crrrrr rr r rz node_boundary..c3s|]}|VqdSNr)rvr rr rsz node_boundary..N)rr from_iterable)r rrrbdyrr r r\s %  )NFFNr)__doc__ itertoolsr__all__rrrrrr s   L