File: pgr_pushRelabel.rst

package info (click to toggle)
pgrouting 4.0.1-1
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid
  • size: 17,332 kB
  • sloc: cpp: 21,315; sql: 10,419; ansic: 9,795; perl: 1,142; sh: 919; javascript: 314; xml: 182; makefile: 29
file content (236 lines) | stat: -rw-r--r-- 5,815 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
:file: This file is part of the pgRouting project.
:copyright: Copyright (c) 2016-2026 pgRouting developers
:license: Creative Commons Attribution-Share Alike 3.0 https://creativecommons.org/licenses/by-sa/3.0

.. index::
   single: Flow Family ; pgr_pushRelabel
   single: pushRelabel

|

``pgr_pushRelabel``
===============================================================================

``pgr_pushRelabel`` — Calculates the flow on the graph edges that maximizes the
flow from the sources to the targets using Push Relabel Algorithm.

.. rubric:: Availability

.. rubric:: Version 4.0.0

* Combinations signature promoted to official.

.. rubric:: Version 3.2.0

* New proposed signature:

  * pgr_pushRelabel(Combinations)

.. rubric:: Version 3.0.0

* Function promoted to official.

.. rubric:: Version 2.5.0

* Renamed from ``pgr_maxFlowPushRelabel``
* Function promoted to proposed.

.. rubric:: Version 2.3.0

* New experimental function.


Description
-------------------------------------------------------------------------------

.. include::  flow-family.rst
    :start-after: characteristics_start
    :end-before: characteristics_end

* Running time: :math:`O( V ^ 3)`

|Boost| Boost Graph Inside

Signatures
-------------------------------------------------------------------------------

.. rubric:: Summary

.. admonition:: \ \
   :class: signatures

   | pgr_pushRelabel(`Edges SQL`_, **start vid**, **end vid**)
   | pgr_pushRelabel(`Edges SQL`_, **start vid**, **end vids**)
   | pgr_pushRelabel(`Edges SQL`_, **start vids**, **end vid**)
   | pgr_pushRelabel(`Edges SQL`_, **start vids**, **end vids**)
   | pgr_pushRelabel(`Edges SQL`_, `Combinations SQL`_)

   | Returns set of |result-flow|
   | OR EMPTY SET

.. index::
    single: pushRelabel ; One to One

One to One
...............................................................................

.. admonition:: \ \
   :class: signatures

   | pgr_pushRelabel(`Edges SQL`_, **start vid**, **end vid**)

   | Returns set of |result-flow|
   | OR EMPTY SET

:Example: From vertex :math:`11` to vertex :math:`12`

.. literalinclude:: pushRelabel.queries
   :start-after: -- q1
   :end-before: -- q2

.. index::
    single: pushRelabel ; One to Many

One to Many
...............................................................................

.. admonition:: \ \
   :class: signatures

   | pgr_pushRelabel(`Edges SQL`_, **start vid**, **end vids**)

   | Returns set of |result-flow|
   | OR EMPTY SET

:Example: From vertex :math:`11` to vertices :math:`\{5, 10, 12\}`

.. literalinclude:: pushRelabel.queries
   :start-after: -- q2
   :end-before: -- q3

.. index::
    single: pushRelabel ; Many to One

Many to One
...............................................................................

.. admonition:: \ \
   :class: signatures

   | pgr_pushRelabel(`Edges SQL`_, **start vids**, **end vid**)

   | Returns set of |result-flow|
   | OR EMPTY SET

:Example: From vertices :math:`\{11, 3, 17\}` to vertex :math:`12`

.. literalinclude:: pushRelabel.queries
   :start-after: -- q3
   :end-before: -- q4

.. index::
    single: pushRelabel ; Many to Many

Many to Many
...............................................................................

.. admonition:: \ \
   :class: signatures

   | pgr_pushRelabel(`Edges SQL`_, **start vids**, **end vids**)

   | Returns set of |result-flow|
   | OR EMPTY SET

:Example: From vertices :math:`\{11, 3, 17\}` to vertices :math:`\{5, 10, 12\}`

.. literalinclude:: pushRelabel.queries
   :start-after: -- q4
   :end-before: -- q5

.. index::
    single: pushRelabel ; Combinations

Combinations
...............................................................................

.. admonition:: \ \
   :class: signatures

   | pgr_pushRelabel(`Edges SQL`_, `Combinations SQL`_)

   | Returns set of |result-flow|
   | OR EMPTY SET

:Example: Using a combinations table, equivalent to calculating result from
          vertices :math:`\{5, 6\}` to vertices :math:`\{10, 15, 14\}`.

The combinations table:

.. literalinclude:: pushRelabel.queries
   :start-after: -- q5
   :end-before: -- q51

The query:

.. literalinclude:: pushRelabel.queries
   :start-after: -- q51
   :end-before: -- q6

Parameters
-------------------------------------------------------------------------------

.. include:: dijkstra-family.rst
    :start-after: dijkstra_parameters_start
    :end-before: dijkstra_parameters_end

Inner Queries
-------------------------------------------------------------------------------

Edges SQL
...............................................................................

.. include:: pgRouting-concepts.rst
    :start-after: flow_edges_sql_start
    :end-before: flow_edges_sql_end

Combinations SQL
...............................................................................

.. include:: pgRouting-concepts.rst
    :start-after: basic_combinations_sql_start
    :end-before: basic_combinations_sql_end

Result columns
-------------------------------------------------------------------------------

.. include:: flow-family.rst
    :start-after: result_flow_start
    :end-before: result_flow_end

Additional Examples
-------------------------------------------------------------------------------

:Example: Manually assigned vertex combinations.

.. literalinclude:: pushRelabel.queries
   :start-after: -- q6
   :end-before: -- q7

See Also
-------------------------------------------------------------------------------

* :doc:`flow-family`

  * :doc:`pgr_boykovKolmogorov`
  * :doc:`pgr_edmondsKarp`

* `Boost: push relabel max flow
  <https://www.boost.org/libs/graph/doc/push_relabel_max_flow.html>`__
* https://en.wikipedia.org/wiki/Push%E2%80%93relabel_maximum_flow_algorithm

.. rubric:: Indices and tables

* :ref:`genindex`
* :ref:`search`