1struct::graph_v1(n) Tcl Data Structures struct::graph_v1(n)
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6
8 struct::graph_v1 - Create and manipulate directed graph objects
9
11 package require Tcl 8.2
12 package require struct::graph ?1.2.1?
14 graphName option ?arg arg ...?
16 graphName destroy
18 graphName arc append arc ?-key key? value
20 graphName arc delete arc ?arc ...?
22 graphName arc exists arc
24 graphName arc get arc ?-key key?
26 graphName arc getall arc
28 graphName arc keys arc
30 graphName arc keyexists arc ?-key key?
32 graphName arc insert start end ?child?
34 graphName arc lappend arc ?-key key? value
36 graphName arc set arc ?-key key? ?value?
38 graphName arc source arc
40 graphName arc target arc
42 graphName arc unset arc ?-key key?
44 graphName arcs ?-key key? ?-value value? ?-in|-out|-adj|-inner|-embed‐
46 ding nodelist?
47 graphName node append node ?-key key? value
49 graphName node degree ?-in|-out? node
51 graphName node delete node ?node ...?
53 graphName node exists node
55 graphName node get node ?-key key?
57 graphName node getall node
59 graphName node keys node
61 graphName node keyexists node ?-key key?
63 graphName node insert ?child?
65 graphName node lappend node ?-key key? value
67 graphName node opposite node arc
69 graphName node set node ?-key key? ?value?
71 graphName node unset node ?-key key?
73 graphName nodes ?-key key? ?-value value? ?-in|-out|-adj|-inner|-embed‐
75 ding nodelist?
76 graphName get ?-key key?
78 graphName getall
80 graphName keys
82 graphName keyexists ?-key key?
84 graphName set ?-key key? ?value?
86 graphName swap node1 node2
88 graphName unset ?-key key?
90 graphName walk node ?-order order? ?-type type? ?-dir direction? -com‐
92 mand cmd
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95
97 The ::struct::graph command creates a new graph object with an associ‐
98 ated global Tcl command whose name is graphName. This command may be
99 used to invoke various operations on the graph. It has the following
100 general form:
101 graphName option ?arg arg ...?
103 Option and the args determine the exact behavior of the command.
104 A directed graph is a structure containing two collections of elements,
106 called nodes and arcs respectively, together with a relation ("connec‐
107 tivity") that places a general structure upon the nodes and arcs.
108 Each arc is connected to two nodes, one of which is called the source
110 and the other the target. This imposes a direction upon the arc, which
111 is said to go from the source to the target. It is allowed that source
112 and target of an arc are the same node. Such an arc is called a loop.
113 Whenever a node is source or target of an arc both are said to be adja‐
114 cent. This extends into a relation between nodes, i.e. if two nodes are
115 connected through at least one arc they are said to be adjacent too.
116 Each node can be the source and target for any number of arcs. The for‐
118 mer are called the outgoing arcs of the node, the latter the incoming
119 arcs of the node. The number of edges in either set is called the in-
120 resp. the out-degree of the node.
121 In addition to maintaining the node and arc relationships, this graph
123 implementation allows any number of keyed values to be associated with
124 each node and arc.
125 The following commands are possible for graph objects:
127 graphName destroy
129 Destroy the graph, including its storage space and associated
130 command.
131 graphName arc append arc ?-key key? value
133 Appends a value to one of the keyed values associated with an
134 arc. If no key is specified, the key data is assumed.
135 graphName arc delete arc ?arc ...?
137 Remove the specified arcs from the graph.
138 graphName arc exists arc
140 Return true if the specified arc exists in the graph.
141 graphName arc get arc ?-key key?
143 Return the value associated with the key key for the arc. If no
144 key is specified, the key data is assumed.
145 graphName arc getall arc
147 Returns a serialized list of key/value pairs (suitable for use
148 with [array set]) for the arc.
149 graphName arc keys arc
151 Returns a list of keys for the arc.
152 graphName arc keyexists arc ?-key key?
154 Return true if the specified key exists for the arc. If no key
155 is specified, the key data is assumed.
156 graphName arc insert start end ?child?
158 Insert an arc named child into the graph beginning at the node
159 start and ending at the node end. If the name of the new arc is
160 not specified the system will generate a unique name of the form
161 arcx.
162 graphName arc lappend arc ?-key key? value
164 Appends a value (as a list) to one of the keyed values associ‐
165 ated with an arc. If no key is specified, the key data is as‐
166 sumed.
167 graphName arc set arc ?-key key? ?value?
169 Set or get one of the keyed values associated with an arc. If
170 no key is specified, the key data is assumed. Each arc that is
171 added to a graph has the empty string assigned to the key data
172 automatically. An arc may have any number of keyed values asso‐
173 ciated with it. If value is not specified, this command returns
174 the current value assigned to the key; if value is specified,
175 this command assigns that value to the key.
176 graphName arc source arc
178 Return the node the given arc begins at.
179 graphName arc target arc
181 Return the node the given arc ends at.
182 graphName arc unset arc ?-key key?
184 Remove a keyed value from the arc arc. If no key is specified,
185 the key data is assumed.
186 graphName arcs ?-key key? ?-value value? ?-in|-out|-adj|-inner|-embed‐
188 ding nodelist?
189 Return a list of arcs in the graph. If no restriction is speci‐
190 fied a list containing all arcs is returned. Restrictions can
191 limit the list of returned arcs based on the nodes that are con‐
192 nected by the arc, on the keyed values associated with the arc,
193 or both. The restrictions that involve connected nodes have a
194 list of nodes as argument, specified after the name of the re‐
195 striction itself.
196 -in Return a list of all arcs whose target is one of the
198 nodes in the nodelist.
199 -out Return a list of all arcs whose source is one of the
201 nodes in the nodelist.
202 -adj Return a list of all arcs adjacent to at least one of the
204 nodes in the nodelist. This is the union of the nodes re‐
205 turned by -in and -out.
206 -inner Return a list of all arcs adjacent to two of the nodes in
208 the nodelist. This is the set of arcs in the subgraph
209 spawned by the specified nodes.
210 -embedding
212 Return a list of all arcs adjacent to exactly one of the
213 nodes in the nodelist. This is the set of arcs connecting
214 the subgraph spawned by the specified nodes to the rest
215 of the graph.
216 -key key
218 Limit the list of arcs that are returned to those arcs
219 that have an associated key key.
220 -value value
222 This restriction can only be used in combination with
223 -key. It limits the list of arcs that are returned to
224 those arcs whose associated key key has the value value.
225 The restrictions imposed by either -in, -out, -adj, -inner, or -embed‐
227 ded are applied first. Specifying more than one of them is illegal. At
228 last the restrictions set via -key (and -value) are applied. Specify‐
229 ing more than one -key (and -value) is illegal.
230 graphName node append node ?-key key? value
232 Appends a value to one of the keyed values associated with an
233 node. If no key is specified, the key data is assumed.
234 graphName node degree ?-in|-out? node
236 Return the number of arcs adjacent to the specified node. If one
237 of the restrictions -in or -out is given only the incoming resp.
238 outgoing arcs are counted.
239 graphName node delete node ?node ...?
241 Remove the specified nodes from the graph. All of the nodes'
242 arcs will be removed as well to prevent unconnected arcs.
243 graphName node exists node
245 Return true if the specified node exists in the graph.
246 graphName node get node ?-key key?
248 Return the value associated with the key key for the node. If
249 no key is specified, the key data is assumed.
250 graphName node getall node
252 Returns a serialized list of key/value pairs (suitable for use
253 with [array set]) for the node.
254 graphName node keys node
256 Returns a list of keys for the node.
257 graphName node keyexists node ?-key key?
259 Return true if the specified key exists for the node. If no key
260 is specified, the key data is assumed.
261 graphName node insert ?child?
263 Insert a node named child into the graph. The nodes has no arcs
264 connected to it. If the name of the new child is not specified
265 the system will generate a unique name of the form nodex.
266 graphName node lappend node ?-key key? value
268 Appends a value (as a list) to one of the keyed values associ‐
269 ated with an node. If no key is specified, the key data is as‐
270 sumed.
271 graphName node opposite node arc
273 Return the node at the other end of the specified arc, which has
274 to be adjacent to the given node.
275 graphName node set node ?-key key? ?value?
277 Set or get one of the keyed values associated with a node. If
278 no key is specified, the key data is assumed. Each node that is
279 added to a graph has the empty string assigned to the key data
280 automatically. A node may have any number of keyed values asso‐
281 ciated with it. If value is not specified, this command returns
282 the current value assigned to the key; if value is specified,
283 this command assigns that value to the key.
284 graphName node unset node ?-key key?
286 Remove a keyed value from the node node. If no key is speci‐
287 fied, the key data is assumed.
288 graphName nodes ?-key key? ?-value value? ?-in|-out|-adj|-inner|-embed‐
290 ding nodelist?
291 Return a list of nodes in the graph. Restrictions can limit the
292 list of returned nodes based on neighboring nodes, or based on
293 the keyed values associated with the node. The restrictions that
294 involve neighboring nodes have a list of nodes as argument,
295 specified after the name of the restriction itself.
296 The possible restrictions are the same as for method arcs. The
298 set of nodes to return is computed as the union of all source
299 and target nodes for all the arcs satisfying the restriction as
300 defined for arcs.
301 graphName get ?-key key?
303 Return the value associated with the key key for the graph. If
304 no key is specified, the key data is assumed.
305 graphName getall
307 Returns a serialized list of key/value pairs (suitable for use
308 with [array set]) for the whole graph.
309 graphName keys
311 Returns a list of keys for the whole graph.
312 graphName keyexists ?-key key?
314 Return true if the specified key exists for the whole graph. If
315 no key is specified, the key data is assumed.
316 graphName set ?-key key? ?value?
318 Set or get one of the keyed values associated with a graph. If
319 no key is specified, the key data is assumed. Each graph has the
320 empty string assigned to the key data automatically. A graph may
321 have any number of keyed values associated with it. If value is
322 not specified, this command returns the current value assigned
323 to the key; if value is specified, this command assigns that
324 value to the key.
325 graphName swap node1 node2
327 Swap the position of node1 and node2 in the graph.
328 graphName unset ?-key key?
330 Remove a keyed value from the graph. If no key is specified, the
331 key data is assumed.
332 graphName walk node ?-order order? ?-type type? ?-dir direction? -com‐
334 mand cmd
335 Perform a breadth-first or depth-first walk of the graph start‐
336 ing at the node node going in either the direction of outgoing
337 or opposite to the incoming arcs.
338 The type of walk, breadth-first or depth-first, is determined by
340 the value of type; bfs indicates breadth-first, dfs indicates
341 depth-first. Depth-first is the default.
342 The order of the walk, pre-order, post-order or both-order is
344 determined by the value of order; pre indicates pre-order, post
345 indicates post-order, both indicates both-order. Pre-order is
346 the default. Pre-order walking means that a node is visited be‐
347 fore any of its neighbors (as defined by the direction, see be‐
348 low). Post-order walking means that a parent is visited after
349 any of its neighbors. Both-order walking means that a node is
350 visited before and after any of its neighbors. The combination
351 of a bread-first walk with post- or both-order is illegal.
352 The direction of the walk is determined by the value of dir;
354 backward indicates the direction opposite to the incoming arcs,
355 forward indicates the direction of the outgoing arcs.
356 As the walk progresses, the command cmd will be evaluated at
358 each node, with the mode of the call (enter or leave) and values
359 graphName and the name of the current node appended. For a pre-
360 order walk, all nodes are entered, for a post-order all nodes
361 are left. In a both-order walk the first visit of a node enters
362 it, the second visit leaves it.
363
365 This document, and the package it describes, will undoubtedly contain
366 bugs and other problems. Please report such in the category struct ::
367 graph of the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist].
368 Please also report any ideas for enhancements you may have for either
369 package and/or documentation.
370 When proposing code changes, please provide unified diffs, i.e the out‐
372 put of diff -u.
373 Note further that attachments are strongly preferred over inlined
375 patches. Attachments can be made by going to the Edit form of the
376 ticket immediately after its creation, and then using the left-most
377 button in the secondary navigation bar.
378
380 cgraph, graph
381
383 Data structures
384
386 Copyright (c) 2002 Andreas Kupries <andreas_kupries@users.sourceforge.net>
387tcllib 1.2.1 struct::graph_v1(n)