pgr_withPointsCost
 Proposed¶
pgr_withPointsCost
 Calculates the shortest path and returns only the
aggregate cost of the shortest path(s) found, for the combination of points
given.
Warning
Proposed functions for next mayor release.
They are not officially in the current release.
They will likely officially be part of the next mayor release:
The functions make use of ANYINTEGER and ANYNUMERICAL
Name might not change. (But still can)
Signature might not change. (But still can)
Functionality might not change. (But still can)
pgTap tests have being done. But might need more.
Documentation might need refinement.
Availability
Version 3.2.0
New proposed function:
pgr_withPointsCost(Combinations)
Version 2.2.0
New proposed function
Description¶
Modify the graph to include points defined by points_sql. Using Dijkstra algorithm, return only the aggregate cost of the shortest path(s) found.
 The main characteristics are:
It does not return a path.
Returns the sum of the costs of the shortest path for pair combination of vertices in the modified graph.
Vertices of the graph are:
positive when it belongs to the edges_sql
negative when it belongs to the points_sql
Process is done only on edges with positive costs.
Values are returned when there is a path.
The returned values are in the form of a set of (start_vid, end_vid, agg_cost).
When the starting vertex and ending vertex are the same, there is no path.
The agg_cost in the non included values (v, v) is 0
When the starting vertex and ending vertex are the different and there is no path.
The agg_cost in the non included values (u, v) is \(\infty\)
If the values returned are stored in a table, the unique index would be the pair: (start_vid, end_vid).
For undirected graphs, the results are symmetric.
The agg_cost of (u, v) is the same as for (v, u).
For optimization purposes, any duplicated value in the start_vids or end_vids is ignored.
The returned values are ordered:
start_vid ascending
end_vid ascending
Running time: \(O(start\_vids\times(V \log V + E))\)
Signatures¶
Summary
[directed, driving_side]
(start_pid, end_pid, agg_cost)
Note
There is no details flag, unlike the other members of the withPoints family of functions.
One to One¶
[directed, driving_side]
(start_pid, end_pid, agg_cost)
 Example:
From point \(1\) to vertex \(10\) with defaults
SELECT * FROM pgr_withPointsCost(
'SELECT id, source, target, cost, reverse_cost FROM edges ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
1, 10);
start_pid  end_pid  agg_cost
++
1  10  5.6
(1 row)
One to Many¶
[directed, driving_side]
(start_pid, end_pid, agg_cost)
 Example:
From point \(1\) to point \(3\) and vertex \(7\) on an undirected graph
SELECT * FROM pgr_withPointsCost(
'SELECT id, source, target, cost, reverse_cost FROM edges ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
1, ARRAY[3, 7],
directed => false);
start_pid  end_pid  agg_cost
++
1  3  3.2
1  7  1.6
(2 rows)
Many to One¶
[directed, driving_side]
(start_pid, end_pid, agg_cost)
 Example:
From point \(1\) and vertex \(6\) to point \(3\)
SELECT * FROM pgr_withPointsCost(
'SELECT id, source, target, cost, reverse_cost FROM edges ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
ARRAY[1, 6], 3);
start_pid  end_pid  agg_cost
++
1  3  3.2
6  3  2.6
(2 rows)
Many to Many¶
[directed, driving_side]
(start_pid, end_pid, agg_cost)
 Example:
From point \(15\) and vertex \(6\) to point \(3\) and vertex \(1\)
SELECT * FROM pgr_withPointsCost(
'SELECT id, source, target, cost, reverse_cost FROM edges ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
ARRAY[1, 6], ARRAY[3, 1]);
start_pid  end_pid  agg_cost
++
1  3  3.2
1  1  3.6
6  3  2.6
6  1  3
(4 rows)
Combinations¶
[directed, driving_side]
(start_pid, end_pid, agg_cost)
 Example:
Two combinations
From point \(1\) to vertex \(10\), and from vertex \(6\) to point \(3\) with right side driving.
SELECT * FROM pgr_withPointsCost(
'SELECT id, source, target, cost, reverse_cost FROM edges ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
'SELECT * FROM (VALUES (1, 10), (6, 3)) AS combinations(source, target)',
driving_side => 'r');
start_pid  end_pid  agg_cost
++
1  10  6.4
6  3  2.6
(2 rows)
Parameters¶
Column 
Type 
Description 


Edges SQL as described below 


Points SQL as described below 


Combinations SQL as described below 

start vid 

Identifier of the starting vertex of the path. Negative value is for point’s identifier. 
start vids 

Array of identifiers of starting vertices. Negative values are for point’s identifiers. 
end vid 

Identifier of the ending vertex of the path. Negative value is for point’s identifier. 
end vids 

Array of identifiers of ending vertices. Negative values are for point’s identifiers. 
Optional parameters¶
Column 
Type 
Default 
Description 





With points optional parameters¶
Parameter 
Type 
Default 
Description 




Value in [

Inner Queries¶
Edges SQL¶
Column 
Type 
Default 
Description 


ANYINTEGER 
Identifier of the edge. 


ANYINTEGER 
Identifier of the first end point vertex of the edge. 


ANYINTEGER 
Identifier of the second end point vertex of the edge. 


ANYNUMERICAL 
Weight of the edge ( 


ANYNUMERICAL 
1 
Weight of the edge (

Where:
 ANYINTEGER:
SMALLINT
,INTEGER
,BIGINT
 ANYNUMERICAL:
SMALLINT
,INTEGER
,BIGINT
,REAL
,FLOAT
Points SQL¶
Parameter 
Type 
Default 
Description 


ANYINTEGER 
value 
Identifier of the point.


ANYINTEGER 
Identifier of the “closest” edge to the point. 


ANYNUMERICAL 
Value in <0,1> that indicates the relative postition from the first end point of the edge. 




Value in [

Where:
 ANYINTEGER:
SMALLINT
,INTEGER
,BIGINT
 ANYNUMERICAL:
SMALLINT
,INTEGER
,BIGINT
,REAL
,FLOAT
Combinations SQL¶
Parameter 
Type 
Description 


ANYINTEGER 
Identifier of the departure vertex. 

ANYINTEGER 
Identifier of the arrival vertex. 
Where:
 ANYINTEGER:
SMALLINT
,INTEGER
,BIGINT
Result columns¶
Column 
Type 
Description 



Identifier of the starting vertex or point.



Identifier of the ending vertex or point.



Aggregate cost from 
Additional Examples¶
Use pgr_findCloseEdges in the Points SQL.¶
Find the cost of the routes from vertex \(1\) to the two closest locations on the graph of point (2.9, 1.8).
SELECT * FROM pgr_withPointsCost(
$e$ SELECT * FROM edges $e$,
$p$ SELECT edge_id, round(fraction::numeric, 2) AS fraction, side
FROM pgr_findCloseEdges(
$$SELECT id, geom FROM edges$$,
(SELECT ST_POINT(2.9, 1.8)),
0.5, cap => 2)
$p$,
1, ARRAY[1, 2]);
start_pid  end_pid  agg_cost
++
1  2  2.9
1  1  6.8
(2 rows)
Point \(1\) corresponds to the closest edge from point (2.9, 1.8).
Point \(2\) corresponds to the next close edge from point (2.9, 1.8).
Being close to the graph does not mean have a shorter route.
Right side driving topology¶
Traveling from point \(1\) and vertex \(5\) to points \(\{2, 3, 6\}\) and vertices \(\{10, 11\}\)
SELECT * FROM pgr_withPointsCost(
'SELECT id, source, target, cost, reverse_cost FROM edges ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
ARRAY[5, 1], ARRAY[2, 3, 6, 10, 11],
driving_side => 'r');
start_pid  end_pid  agg_cost
++
1  6  2.1
1  3  4
1  2  4.8
1  10  6.4
1  11  3.4
5  6  1.7
5  3  3.6
5  2  4.4
5  10  6
5  11  3
(10 rows)
Left side driving topology¶
Traveling from point \(1\) and vertex \(5\) to points \(\{2, 3, 6\}\) and vertices \(\{10, 11\}\)
SELECT * FROM pgr_withPointsCost(
'SELECT id, source, target, cost, reverse_cost FROM edges ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
ARRAY[5, 1], ARRAY[2, 3, 6, 10, 11],
driving_side => 'l');
start_pid  end_pid  agg_cost
++
1  6  1.3
1  3  3.2
1  2  5.2
1  10  5.6
1  11  2.6
5  6  1.7
5  3  3.6
5  2  5.6
5  10  6
5  11  3
(10 rows)
Does not matter driving side driving topology¶
Traveling from point \(1\) and vertex \(5\) to points \(\{2, 3, 6\}\) and vertices \(\{10, 11\}\)
SELECT * FROM pgr_withPointsCost(
'SELECT id, source, target, cost, reverse_cost FROM edges ORDER BY id',
'SELECT pid, edge_id, fraction, side from pointsOfInterest',
ARRAY[5, 1], ARRAY[2, 3, 6, 10, 11]);
start_pid  end_pid  agg_cost
++
1  6  1.3
1  3  3.2
1  2  4
1  10  5.6
1  11  2.6
5  6  1.7
5  3  3.6
5  2  4.4
5  10  6
5  11  3
(10 rows)
The queries use the Sample Data network.
See Also¶
Indices and tables