pgr_chinesePostmanCost - Experimental¶
pgr_chinesePostmanCost
— Calculates the minimum costs of a circuit path which
contains every edge in a directed graph and starts and ends on the same vertex.
Warning
Possible server crash
These functions might create a server crash
Warning
Experimental functions
They are not officially of the current release.
They likely will not be officially be part of the next release:
The functions might not make use of ANY-INTEGER and ANY-NUMERICAL
Name might change.
Signature might change.
Functionality might change.
pgTap tests might be missing.
Might need c/c++ coding.
May lack documentation.
Documentation if any might need to be rewritten.
Documentation examples might need to be automatically generated.
Might need a lot of feedback from the comunity.
Might depend on a proposed function of pgRouting
Might depend on a deprecated function of pgRouting
Availability
Version 3.0.0
New experimental function
Description¶
The main characteristics are:
Process is done only on edges with positive costs.
Running time: \(O(E * (E + V * logV))\)
Graph must be connected.
[TBD] Return value when the graph if disconnected
Signatures¶
pgr_chinesePostmanCost(edges_sql)
RETURNS FLOAT
- Example
SELECT * FROM pgr_chinesePostmanCost(
'SELECT id,
source, target,
cost, reverse_cost FROM edge_table where id < 17'
);
pgr_chinesepostmancost
------------------------
34
(1 row)
Parameters¶
Column |
Type |
Default |
Description |
---|---|---|---|
edges_sql |
|
The edges SQL query as described in Inner query. |
Inner query¶
An Edges SQL that represents a directed graph with the following columns
Column |
Type |
Default |
Description |
---|---|---|---|
id |
|
Identifier of the edge. |
|
source |
|
Identifier of the first end point vertex of the edge. |
|
target |
|
Identifier of the second end point vertex of the edge. |
|
cost |
|
Weight of the edge (source, target)
|
|
reverse_cost |
|
-1 |
Weight of the edge (target, source),
|
Where:
- ANY-INTEGER
SMALLINT, INTEGER, BIGINT
- ANY-NUMERICAL
SMALLINT, INTEGER, BIGINT, REAL, FLOAT
Result Columns¶
Type |
Description |
---|---|
|
Minimum costs of a circuit path. |
See Also¶
Indices and tables