pgr_bdAstarCost¶
pgr_bdAstarCost
— Returns the aggregate cost shortest path using pgr_aStar algorithm.

Boost Graph Inside¶
Availability
Version 3.0.0
Official function
Version 2.5.0
New Proposed function
Unsupported versions: 2.5
Description¶
Default kind of graph is directed when
directed
flag is missing.directed
flag is set to true
Unless specified otherwise, ordering is:
first by
start_vid
(if exists)then by
end_vid
Values are returned when there is a path
Let \(v\) and \(u\) be nodes on the graph:
If there is no path from \(v\) to \(u\):
no corresponding row is returned
agg_cost
from \(v\) to \(u\) is \(\infty\)
There is no path when \(v = u\) therefore
no corresponding row is returned
agg_cost
from v to u is \(0\)
Edges with negative costs are not included in the graph.
When (x,y) coordinates for the same vertex identifier differ:
A random selection of the vertex’s (x,y) coordinates is used.
Running time: \(O((E + V) * \log V)\)
The results are equivalent to the union of the results of the pgr_bdAstarCost( One to One ) on the:
pgr_bdAstarCost( One to Many )
pgr_bdAstarCost( Many to One )
pgr_bdAstarCost( Many to Many )
Signatures¶
Summary
pgr_bdAstarCost(edges_sql, from_vid, to_vid [, directed] [, heuristic] [, factor] [, epsilon])
pgr_bdAstarCost(edges_sql, from_vid, to_vids [, directed] [, heuristic] [, factor] [, epsilon])
pgr_bdAstarCost(edges_sql, from_vids, to_vid [, directed] [, heuristic] [, factor] [, epsilon])
pgr_bdAstarCost(edges_sql, from_vids, to_vids [, directed] [, heuristic] [, factor] [, epsilon])
RETURNS SET OF (start_vid, end_vid, agg_cost)
OR EMPTY SET
Optional parameters are named parameters and have a default value.
Using defaults
pgr_bdAstarCost(edges_sql, from_vid, to_vid)
RETURNS SET OF (start_vid, end_vid, agg_cost)
OR EMPTY SET
- Example
From vertex \(2\) to vertex \(3\) on a directed graph
SELECT * FROM pgr_bdAstarCost(
'SELECT id, source, target, cost, reverse_cost, x1,y1,x2,y2
FROM edge_table',
2, 3
);
start_vid | end_vid | agg_cost
-----------+---------+----------
2 | 3 | 5
(1 row)
One to One¶
pgr_bdAstarCost(edges_sql, from_vid, to_vid [, directed] [, heuristic] [, factor] [, epsilon])
RETURNS SET OF (start_vid, end_vid, agg_cost)
OR EMPTY SET
- Example
From vertex \(2\) to vertex \(3\) on an directed graph using heuristic \(2\)
SELECT * FROM pgr_bdAstarCost(
'SELECT id, source, target, cost, reverse_cost, x1,y1,x2,y2
FROM edge_table',
2, 3,
true, heuristic := 2
);
start_vid | end_vid | agg_cost
-----------+---------+----------
2 | 3 | 5
(1 row)
One to many¶
pgr_bdAstarCost(edges_sql, from_vid, to_vids [, directed] [, heuristic] [, factor] [, epsilon])
RETURNS SET OF (start_vid, end_vid, agg_cost)
OR EMPTY SET
- Example
From vertex 2 to vertices \(\{3, 11\}\) on a directed graph using heuristic 3 and factor \(3.5\)
SELECT * FROM pgr_bdAstarCost(
'SELECT id, source, target, cost, reverse_cost, x1,y1,x2,y2
FROM edge_table',
2, ARRAY[3, 11],
heuristic := 3, factor := 3.5
);
start_vid | end_vid | agg_cost
-----------+---------+----------
2 | 3 | 5
2 | 11 | 3
(2 rows)
Many to One¶
pgr_bdAstarCost(edges_sql, from_vids, to_vid [, directed] [, heuristic] [, factor] [, epsilon])
RETURNS SET OF (start_vid, end_vid, agg_cost)
OR EMPTY SET
- Example
From vertices \(\{7, 2\}\) to vertex \(3\) on a undirected graph using heuristic \(4\)
SELECT * FROM pgr_bdAstarCost(
'SELECT id, source, target, cost, reverse_cost, x1,y1,x2,y2
FROM edge_table',
ARRAY[2, 7], 3,
false, heuristic := 4
);
start_vid | end_vid | agg_cost
-----------+---------+----------
2 | 3 | 1
7 | 3 | 4
(2 rows)
Many to Many¶
pgr_bdAstarCost(edges_sql, from_vids, to_vids [, directed] [, heuristic] [, factor] [, epsilon])
RETURNS SET OF (start_vid, end_vid, agg_cost)
OR EMPTY SET
- Example
From vertices \(\{7, 2\}\) to vertices \(\{3, 11\}\) on a directed using heuristic \(5\) and factor \(0.5\)
SELECT * FROM pgr_bdAstarCost(
'SELECT id, source, target, cost, reverse_cost, x1,y1,x2,y2
FROM edge_table',
ARRAY[2, 7], ARRAY[3, 11],
factor := 0.5
);
start_vid | end_vid | agg_cost
-----------+---------+----------
2 | 3 | 5
2 | 11 | 3
7 | 3 | 6
7 | 11 | 4
(4 rows)
Parameters¶
Parameter |
Type |
Description |
---|---|---|
edges_sql |
|
edges_sql inner query. |
from_vid |
|
Starting vertex identifier. Parameter in: |
from_vids |
|
Array of starting vertices identifiers. Parameter in: |
to_vid |
|
Ending vertex identifier. Parameter in: |
to_vids |
|
Array of ending vertices identifiers. Parameter in: |
Optional Parameters¶
Parameter |
Type |
Default |
Description |
---|---|---|---|
directed |
|
|
|
heuristic |
|
|
Heuristic number. Current valid values 0~5. Default
|
factor |
|
|
For units manipulation. \(factor > 0\). See Factor |
epsilon |
|
|
For less restricted results. \(epsilon >= 1\). |
Inner query¶
edges_sql¶
- edges_sql
an SQL query, which should return a set of rows 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),
|
x1 |
|
X coordinate of source vertex. |
|
y1 |
|
Y coordinate of source vertex. |
|
x2 |
|
X coordinate of target vertex. |
|
y2 |
|
Y coordinate of target vertex. |
Where:
- ANY-INTEGER
SMALLINT, INTEGER, BIGINT
- ANY-NUMERICAL
SMALLINT, INTEGER, BIGINT, REAL, FLOAT
Result Columns¶
Returns SET OF (start_vid, end_vid, agg_cost)
Column |
Type |
Description |
---|---|---|
start_vid |
|
Identifier of the starting vertex. |
end_vid |
|
Identifier of the ending vertex. |
agg_cost |
|
Aggregate cost from |