|
1
|
|
|
<?php |
|
2
|
|
|
|
|
3
|
|
|
namespace Graphp; |
|
4
|
|
|
|
|
5
|
|
|
use Exception; |
|
6
|
|
|
use InvalidArgumentException; |
|
7
|
|
|
use Graphp\Edge\EdgeInterface; |
|
8
|
|
|
use Graphp\Edge\EdgeSet; |
|
9
|
|
|
use Graphp\Vertex\VertexInterface; |
|
10
|
|
|
use Graphp\Vertex\VertexSet; |
|
11
|
|
|
|
|
12
|
|
|
/** |
|
13
|
|
|
* Class GraphUtils |
|
14
|
|
|
* |
|
15
|
|
|
* @package Graphp |
|
16
|
|
|
*/ |
|
17
|
|
|
class GraphUtils |
|
18
|
|
|
{ |
|
19
|
|
|
/** |
|
20
|
|
|
* Create a new edge and add it to the specified graph |
|
21
|
|
|
* |
|
22
|
|
|
* @param GraphInterface $graph - the graph |
|
23
|
|
|
* @param VertexInterface $sourceVertex - the source vertex |
|
24
|
|
|
* @param VertexInterface $targetVertex - the target vertex |
|
25
|
|
|
* @param float $weight - the weight of the edge being added |
|
26
|
|
|
* |
|
27
|
|
|
* @return EdgeInterface |
|
28
|
|
|
*/ |
|
29
|
9 |
|
public static function addEdge( |
|
30
|
|
|
GraphInterface $graph, |
|
31
|
|
|
VertexInterface $sourceVertex, |
|
32
|
|
|
VertexInterface $targetVertex, |
|
33
|
|
|
?float $weight = null |
|
34
|
|
|
): ?EdgeInterface { |
|
35
|
9 |
|
$edgeSupplier = $graph->getEdgeSupplier(); |
|
36
|
9 |
|
if (is_null($edgeSupplier)) { |
|
37
|
|
|
throw new Exception("Graph contains no edge supplier"); |
|
38
|
|
|
} |
|
39
|
9 |
|
$edge = $edgeSupplier->get(); |
|
40
|
|
|
|
|
41
|
9 |
|
if ($graph->addEdge($sourceVertex, $targetVertex, $edge)) { |
|
42
|
9 |
|
if ($graph->getType()->isWeighted()) { |
|
43
|
4 |
|
$graph->setEdgeWeight($edge, $weight); |
|
44
|
|
|
} |
|
45
|
9 |
|
return $edge; |
|
46
|
|
|
} |
|
47
|
1 |
|
return null; |
|
48
|
|
|
} |
|
49
|
|
|
|
|
50
|
|
|
/** |
|
51
|
|
|
* Add the speficied source and target vertices to the graph |
|
52
|
|
|
* |
|
53
|
|
|
* @param GraphInterface $graph - the graph |
|
54
|
|
|
* @param VertexInterface $sourceVertex - the source vertex |
|
55
|
|
|
* @param VertexInterface $targetVertex - the target vertex |
|
56
|
|
|
* @param float $weight - the weight of the edge being added |
|
57
|
|
|
* |
|
58
|
|
|
* @return EdgeInterface |
|
59
|
|
|
*/ |
|
60
|
5 |
|
public static function addEdgeWithVertices( |
|
61
|
|
|
GraphInterface $graph, |
|
62
|
|
|
VertexInterface $sourceVertex, |
|
63
|
|
|
VertexInterface $targetVertex, |
|
64
|
|
|
?float $weight = null |
|
65
|
|
|
): EdgeInterface { |
|
66
|
5 |
|
$graph->addVertex($sourceVertex); |
|
67
|
5 |
|
$graph->addVertex($targetVertex); |
|
68
|
5 |
|
return self::addEdge($graph, $sourceVertex, $targetVertex, $weight); |
|
|
|
|
|
|
69
|
|
|
} |
|
70
|
|
|
|
|
71
|
|
|
/** |
|
72
|
|
|
* Add all the vertices and all the edges of the source graph to the target graph. |
|
73
|
|
|
* Return true, if the target graph was changed |
|
74
|
|
|
* |
|
75
|
|
|
* @param GraphInterface $targetGraph - the target graph |
|
76
|
|
|
* @param GraphInterface $sourceGraph - the source graph |
|
77
|
|
|
* |
|
78
|
|
|
* @return bool |
|
79
|
|
|
*/ |
|
80
|
2 |
|
public static function addGraph(GraphInterface $targetGraph, GraphInterface $sourceGraph): bool |
|
81
|
|
|
{ |
|
82
|
2 |
|
$modified = self::addAllVertices($targetGraph, $sourceGraph->vertexSet()); |
|
83
|
2 |
|
return self::addAllEdges($targetGraph, $sourceGraph, $sourceGraph->edgeSet()) || $modified; |
|
84
|
|
|
} |
|
85
|
|
|
|
|
86
|
|
|
/** |
|
87
|
|
|
* Add all vertices to the specified graph. |
|
88
|
|
|
* Return true, if the graph was modified |
|
89
|
|
|
* |
|
90
|
|
|
* @param GraphInterface $graph - the target graph |
|
91
|
|
|
* @param VertexSet $vertices - the vertices |
|
92
|
|
|
* |
|
93
|
|
|
* @return bool |
|
94
|
|
|
*/ |
|
95
|
15 |
|
public static function addAllVertices(GraphInterface $graph, VertexSet $vertices): bool |
|
96
|
|
|
{ |
|
97
|
15 |
|
$modified = false; |
|
98
|
15 |
|
foreach ($vertices as $vertex) { |
|
99
|
15 |
|
$modified = $graph->addVertex($vertex) || $modified; |
|
100
|
|
|
} |
|
101
|
15 |
|
return $modified; |
|
102
|
|
|
} |
|
103
|
|
|
|
|
104
|
|
|
/** |
|
105
|
|
|
* Add all edges of the source graph to the target graph. |
|
106
|
|
|
* Return true, if the graph was modified |
|
107
|
|
|
* |
|
108
|
|
|
* @param GraphInterface $targetGraph - the target graph |
|
109
|
|
|
* @param GraphInterface $sourceGraph - the source graph |
|
110
|
|
|
* @param EdgeSet $edges - the edges to add |
|
111
|
|
|
* |
|
112
|
|
|
* @return bool |
|
113
|
|
|
*/ |
|
114
|
2 |
|
public static function addAllEdges( |
|
115
|
|
|
GraphInterface $targetGraph, |
|
116
|
|
|
GraphInterface $sourceGraph, |
|
117
|
|
|
EdgeSet $edges |
|
118
|
|
|
): bool { |
|
119
|
2 |
|
$modified = false; |
|
120
|
2 |
|
foreach ($edges as $edge) { |
|
121
|
2 |
|
$sourceVertex = $sourceGraph->getEdgeSource($edge); |
|
122
|
2 |
|
$targetVertex = $sourceGraph->getEdgeTarget($edge); |
|
123
|
2 |
|
$targetGraph->addVertex($sourceVertex); |
|
124
|
2 |
|
$targetGraph->addVertex($targetVertex); |
|
125
|
2 |
|
$modified = $targetGraph->addEdge($sourceVertex, $targetVertex, $edge) || $modified; |
|
126
|
|
|
} |
|
127
|
2 |
|
return $modified; |
|
128
|
|
|
} |
|
129
|
|
|
|
|
130
|
|
|
/** |
|
131
|
|
|
* Add all the vertices and all the edges of the source graph to the target graph in the reversed order |
|
132
|
|
|
* |
|
133
|
|
|
* @param GraphInterface $targetGraph - the target graph |
|
134
|
|
|
* @param GraphInterface $sourceGraph - the source graph |
|
135
|
|
|
*/ |
|
136
|
1 |
|
public static function addGraphReversed(GraphInterface $targetGraph, GraphInterface $sourceGraph): void |
|
137
|
|
|
{ |
|
138
|
1 |
|
if (!$sourceGraph->getType()->isDirected() || !$targetGraph->getType()->isDirected()) { |
|
139
|
|
|
throw new InvalidArgumentException("graph must be directed"); |
|
140
|
|
|
} |
|
141
|
|
|
|
|
142
|
1 |
|
self::addAllVertices($targetGraph, $sourceGraph->vertexSet()); |
|
143
|
|
|
|
|
144
|
1 |
|
$edges = $sourceGraph->edgeSet(); |
|
145
|
1 |
|
foreach ($edges as $edge) { |
|
146
|
1 |
|
$targetGraph->addEdge($sourceGraph->getEdgeTarget($edge), $sourceGraph->getEdgeSource($edge)); |
|
147
|
|
|
} |
|
148
|
1 |
|
} |
|
149
|
|
|
|
|
150
|
|
|
/** |
|
151
|
|
|
* Get a list of vertices that are the neighbors of a specified vertex. |
|
152
|
|
|
* |
|
153
|
|
|
* @param GraphInterface $graph - the graph |
|
154
|
|
|
* @param VertexInterface $vertex - the vertex |
|
155
|
|
|
* |
|
156
|
|
|
* @return array |
|
157
|
|
|
*/ |
|
158
|
3 |
|
public static function neighborsOf(GraphInterface $graph, VertexInterface $vertex): array |
|
159
|
|
|
{ |
|
160
|
3 |
|
$neighbors = []; |
|
161
|
3 |
|
$edges = $graph->edgesOf($vertex); |
|
162
|
3 |
|
foreach ($edges as $edge) { |
|
163
|
3 |
|
$neighbors[] = self::getOppositeVertex($graph, $edge, $vertex); |
|
164
|
|
|
} |
|
165
|
3 |
|
return $neighbors; |
|
166
|
|
|
} |
|
167
|
|
|
|
|
168
|
|
|
/** |
|
169
|
|
|
* Get a list of vertices that are the direct predecessors of a specified vertex. |
|
170
|
|
|
* |
|
171
|
|
|
* @param GraphInterface $graph - the graph |
|
172
|
|
|
* @param VertexInterface $vertex - the vertex |
|
173
|
|
|
* |
|
174
|
|
|
* @return array |
|
175
|
|
|
*/ |
|
176
|
2 |
|
public static function predecessorsOf(GraphInterface $graph, VertexInterface $vertex): array |
|
177
|
|
|
{ |
|
178
|
2 |
|
$neighbors = []; |
|
179
|
2 |
|
$edges = $graph->incomingEdgesOf($vertex); |
|
180
|
2 |
|
foreach ($edges as $edge) { |
|
181
|
2 |
|
$neighbors[] = self::getOppositeVertex($graph, $edge, $vertex); |
|
182
|
|
|
} |
|
183
|
2 |
|
return $neighbors; |
|
184
|
|
|
} |
|
185
|
|
|
|
|
186
|
|
|
/** |
|
187
|
|
|
* Get a list of vertices that are the direct successors of a specified vertex. |
|
188
|
|
|
* |
|
189
|
|
|
* @param GraphInterface $graph - the graph |
|
190
|
|
|
* @param VertexInterface $vertex - the vertex |
|
191
|
|
|
* |
|
192
|
|
|
* @return array |
|
193
|
|
|
*/ |
|
194
|
1 |
|
public static function successorsOf(GraphInterface $graph, VertexInterface $vertex): array |
|
195
|
|
|
{ |
|
196
|
1 |
|
$neighbors = []; |
|
197
|
1 |
|
$edges = $graph->outgoingEdgesOf($vertex); |
|
198
|
1 |
|
foreach ($edges as $edge) { |
|
199
|
1 |
|
$neighbors[] = self::getOppositeVertex($graph, $edge, $vertex); |
|
200
|
|
|
} |
|
201
|
1 |
|
return $neighbors; |
|
202
|
|
|
} |
|
203
|
|
|
|
|
204
|
|
|
/** |
|
205
|
|
|
* Test whether an edge is incident to a vertex. |
|
206
|
|
|
* |
|
207
|
|
|
* @param GraphInterface $graph - the graph |
|
208
|
|
|
* @param EdgeInterface $edge - the edge |
|
209
|
|
|
* @param VertexInterface $vertex - the vertex |
|
210
|
|
|
* |
|
211
|
|
|
* @return bool |
|
212
|
|
|
*/ |
|
213
|
3 |
|
public static function testIncidence(GraphInterface $graph, EdgeInterface $edge, VertexInterface $vertex): bool |
|
214
|
|
|
{ |
|
215
|
3 |
|
return $graph->getEdgeSource($edge)->equals($vertex) |
|
216
|
3 |
|
|| $graph->getEdgeTarget($edge)->equals($vertex); |
|
217
|
|
|
} |
|
218
|
|
|
|
|
219
|
|
|
/** |
|
220
|
|
|
* Get the vertex opposite another vertex across an edge. |
|
221
|
|
|
* |
|
222
|
|
|
* @param GraphInterface $graph - the graph |
|
223
|
|
|
* @param EdgeInterface $edge - the edge |
|
224
|
|
|
* @param VertexInterface $vertex - the vertex |
|
225
|
|
|
* |
|
226
|
|
|
* @return VertexInterface |
|
227
|
|
|
*/ |
|
228
|
15 |
|
public static function getOppositeVertex( |
|
229
|
|
|
GraphInterface $graph, |
|
230
|
|
|
EdgeInterface $edge, |
|
231
|
|
|
VertexInterface $vertex |
|
232
|
|
|
): VertexInterface { |
|
233
|
15 |
|
$source = $graph->getEdgeSource($edge); |
|
234
|
15 |
|
$target = $graph->getEdgeTarget($edge); |
|
235
|
15 |
|
if ($vertex->equals($source)) { |
|
236
|
12 |
|
return $target; |
|
237
|
12 |
|
} elseif ($vertex->equals($target)) { |
|
238
|
12 |
|
return $source; |
|
239
|
|
|
} else { |
|
240
|
|
|
throw new InvalidArgumentException("no such vertex: " . (string) $vertex); |
|
241
|
|
|
} |
|
242
|
|
|
} |
|
243
|
|
|
|
|
244
|
|
|
/** |
|
245
|
|
|
* Remove the given vertices from the given graph. If the vertex to be removed has one or more |
|
246
|
|
|
* predecessors, the predecessors will be connected directly to the successors of the vertex to |
|
247
|
|
|
* be removed. |
|
248
|
|
|
* |
|
249
|
|
|
* @param GraphInterface $graph - the graph |
|
250
|
|
|
* @param VertexInterface $vertex - the vertex to be removed |
|
251
|
|
|
* @param mixed $vertices - the remaining vertices |
|
252
|
|
|
* |
|
253
|
|
|
* @return bool |
|
254
|
|
|
*/ |
|
255
|
1 |
|
public static function removeVertexAndPreserveConnectivity( |
|
256
|
|
|
GraphInterface $graph, |
|
257
|
|
|
VertexInterface $vertex, |
|
258
|
|
|
...$vertices |
|
259
|
|
|
): bool { |
|
260
|
1 |
|
if (!$graph->containsVertex($vertex)) { |
|
261
|
|
|
return false; |
|
262
|
|
|
} |
|
263
|
|
|
|
|
264
|
1 |
|
$vertices[] = $vertex; |
|
265
|
1 |
|
foreach ($vertices as $vertex) { |
|
266
|
1 |
|
if (self::vertexHasPredecessors($graph, $vertex)) { |
|
267
|
1 |
|
$predecessors = self::predecessorsOf($graph, $vertex); |
|
268
|
1 |
|
$successors = self::successorsOf($graph, $vertex); |
|
269
|
|
|
|
|
270
|
1 |
|
foreach ($predecessors as $predecessor) { |
|
271
|
1 |
|
self::addOutgoingEdges($graph, $predecessor, ...$successors); |
|
272
|
|
|
} |
|
273
|
|
|
} |
|
274
|
1 |
|
$graph->removeVertex($vertex); |
|
275
|
|
|
} |
|
276
|
|
|
|
|
277
|
1 |
|
return true; |
|
278
|
|
|
} |
|
279
|
|
|
|
|
280
|
|
|
/** |
|
281
|
|
|
* Add edges from one source vertex to multiple target vertices |
|
282
|
|
|
* |
|
283
|
|
|
* @param GraphInterface $graph - the graph |
|
284
|
|
|
* @param VertexInterface $vertex - the source vertex |
|
285
|
|
|
* @param mixed $vertices - the target vertices |
|
286
|
|
|
*/ |
|
287
|
2 |
|
public static function addOutgoingEdges(GraphInterface $graph, VertexInterface $vertex, ...$vertices): void |
|
288
|
|
|
{ |
|
289
|
2 |
|
if (!$graph->containsVertex($vertex)) { |
|
290
|
|
|
$graph->addVertex($vertex); |
|
291
|
|
|
} |
|
292
|
2 |
|
foreach ($vertices as $target) { |
|
293
|
2 |
|
if (!$graph->containsVertex($target)) { |
|
294
|
1 |
|
$graph->addVertex($target); |
|
295
|
|
|
} |
|
296
|
2 |
|
$graph->addEdge($vertex, $target); |
|
297
|
|
|
} |
|
298
|
2 |
|
} |
|
299
|
|
|
|
|
300
|
|
|
/** |
|
301
|
|
|
* Add edges from multiple source vertices to one target vertex |
|
302
|
|
|
* |
|
303
|
|
|
* @param GraphInterface $graph - the graph |
|
304
|
|
|
* @param VertexInterface $vertex - the target vertex |
|
305
|
|
|
* @param mixed $vertices - the source vertices |
|
306
|
|
|
*/ |
|
307
|
1 |
|
public static function addIncomingEdges(GraphInterface $graph, VertexInterface $vertex, ...$vertices): void |
|
308
|
|
|
{ |
|
309
|
1 |
|
if (!$graph->containsVertex($vertex)) { |
|
310
|
|
|
$graph->addVertex($vertex); |
|
311
|
|
|
} |
|
312
|
1 |
|
foreach ($vertices as $source) { |
|
313
|
1 |
|
if (!$graph->containsVertex($source)) { |
|
314
|
1 |
|
$graph->addVertex($source); |
|
315
|
|
|
} |
|
316
|
1 |
|
$graph->addEdge($source, $vertex); |
|
317
|
|
|
} |
|
318
|
1 |
|
} |
|
319
|
|
|
|
|
320
|
|
|
/** |
|
321
|
|
|
* Check if the vertex has direct successors |
|
322
|
|
|
* |
|
323
|
|
|
* @param GraphInterface $graph - the graph |
|
324
|
|
|
* @param VertexInterface $vertex - the vertex |
|
325
|
|
|
* |
|
326
|
|
|
* @return bool |
|
327
|
|
|
*/ |
|
328
|
1 |
|
public static function vertexHasSuccessors(GraphInterface $graph, VertexInterface $vertex): bool |
|
329
|
|
|
{ |
|
330
|
1 |
|
return count($graph->outgoingEdgesOf($vertex)) > 0; |
|
331
|
|
|
} |
|
332
|
|
|
|
|
333
|
|
|
/** |
|
334
|
|
|
* Check if the vertex has direct predecessors |
|
335
|
|
|
* |
|
336
|
|
|
* @param GraphInterface $graph - the graph |
|
337
|
|
|
* @param VertexInterface $vertex - the vertex |
|
338
|
|
|
* |
|
339
|
|
|
* @return bool |
|
340
|
|
|
*/ |
|
341
|
2 |
|
public static function vertexHasPredecessors(GraphInterface $graph, VertexInterface $vertex): bool |
|
342
|
|
|
{ |
|
343
|
2 |
|
return count($graph->incomingEdgesOf($vertex)) > 0; |
|
344
|
|
|
} |
|
345
|
|
|
} |
|
346
|
|
|
|