pgr_aStarCost
— Returns the aggregate cost shortest path using aStar  Family of functions algorithm.
Availability: 2.4.0
Warning
These are proposed functions for next mayor release.
pgr_aStarCost(edges_sql, start_vid, end_vid)  Proposed
pgr_aStarCost(edges_sql, start_vid, end_vid, directed, heuristic, factor, epsilon)  Proposed
pgr_aStarCost(edges_sql, start_vid, end_vids, directed, heuristic, factor, epsilon)  Proposed
pgr_aStarCost(edges_sql, starts_vid, end_vid, directed, heuristic, factor, epsilon)  Proposed
pgr_aStarCost(edges_sql, starts_vid, end_vids, directed, heuristic, factor, epsilon)  Proposed
RETURNS SET OF (start_vid, end_vid, agg_cost) OR EMPTY SET
pgr_aStarCost(edges_sql, start_vid, end_vid)
RETURNS SET OF (start_vid, end_vid, agg_cost) OR EMPTY SET
Example:  Using the defaults 

SELECT * FROM pgr_aStarCost(
'SELECT id, source, target, cost, reverse_cost, x1, y1, x2, y2 FROM edge_table',
2, 12);
start_vid  end_vid  agg_cost
++
2  12  4
(1 row)
pgr_aStarCost(edges_sql, start_vid, end_vid, directed, heuristic, factor, epsilon)
RETURNS SET OF (start_vid, end_vid, agg_cost) OR EMPTY SET
Example:  Setting a Heuristic 

SELECT * FROM pgr_aStarCost(
'SELECT id, source, target, cost, reverse_cost, x1, y1, x2, y2 FROM edge_table',
2, 12,
directed := false, heuristic := 2);
start_vid  end_vid  agg_cost
++
2  12  4
(1 row)
pgr_aStarCost(edges_sql, start_vid, end_vids, directed, heuristic, factor, epsilon)  Proposed
RETURNS SET OF (start_vid, end_vid, agg_cost) OR EMPTY SET
start_vid
to each end_vid
in end_vids
:directed
flag is missing or is set to true
.directed
flag is set to false
.Using this signature, will load once the graph and perform a one to one pgr_astar
where the starting vertex is fixed, and stop when all end_vids
are reached.
 The result is equivalent to the union of the results of the one to one pgr_astar.
 The extra
end_vid
column in the result is used to distinguish to which path it belongs.
Example: 

SELECT * FROM pgr_aStarCost(
'SELECT id, source, target, cost, reverse_cost, x1, y1, x2, y2 FROM edge_table',
2, ARRAY[3, 12], heuristic := 2);
start_vid  end_vid  agg_cost
++
2  3  5
2  12  4
(2 rows)
pgr_aStarCost(edges_sql, starts_vid, end_vid, directed, heuristic, factor, epsilon)  Proposed
RETURNS SET OF (start_vid, end_vid, agg_cost) OR EMPTY SET
start_vid
in start_vids
to one end_vid
:directed
flag is missing or is set to true
.directed
flag is set to false
.Using this signature, will load once the graph and perform several one to one pgr_aStar where the ending vertex is fixed.
 The result is the union of the results of the one to one pgr_aStar.
 The extra
start_vid
column in the result is used to distinguish to which path it belongs.
Example: 

SELECT * FROM pgr_aStarCost(
'SELECT id, source, target, cost, reverse_cost, x1, y1, x2, y2 FROM edge_table',
ARRAY[7, 2], 12, heuristic := 0);
start_vid  end_vid  agg_cost
++
2  12  4
7  12  5
(2 rows)
pgr_aStarCost(edges_sql, starts_vid, end_vids, directed, heuristic, factor, epsilon)  Proposed
RETURNS SET OF (start_vid, end_vid, agg_cost) OR EMPTY SET
start_vid
in start_vids
to each end_vid
in end_vids
:directed
flag is missing or is set to true
.directed
flag is set to false
.Using this signature, will load once the graph and perform several one to Many pgr_dijkstra
for all start_vids
.
 The result is the union of the results of the one to one pgr_dijkstra.
 The extra
start_vid
in the result is used to distinguish to which path it belongs.
The extra start_vid
and end_vid
in the result is used to distinguish to which path it belongs.
Example: 

SELECT * FROM pgr_aStarCost(
'SELECT id, source, target, cost, reverse_cost, x1, y1, x2, y2 FROM edge_table',
ARRAY[7, 2], ARRAY[3, 12], heuristic := 2);
start_vid  end_vid  agg_cost
++
2  3  5
2  12  4
7  3  6
7  12  5
(4 rows)
edges_sql:  an SQL query, which should return a set of rows with the following columns: 

Column  Type  Default  Description 

id  ANYINTEGER 
Identifier of the edge.  
source  ANYINTEGER 
Identifier of the first end point vertex of the edge.  
target  ANYINTEGER 
Identifier of the second end point vertex of the edge.  
cost  ANYNUMERICAL 
Weight of the edge (source, target)


reverse_cost  ANYNUMERICAL 
1  Weight of the edge (target, source),

x1  ANYNUMERICAL 
X coordinate of source vertex.  
y1  ANYNUMERICAL 
Y coordinate of source vertex.  
x2  ANYNUMERICAL 
X coordinate of target vertex.  
y2  ANYNUMERICAL 
Y coordinate of target vertex. 
Where:
ANYINTEGER:  SMALLINT, INTEGER, BIGINT 

ANYNUMERICAL:  SMALLINT, INTEGER, BIGINT, REAL, FLOAT 
Parameter  Type  Description 

edges_sql  TEXT 
Edges SQL query as described above. 
start_vid  ANYINTEGER 
Starting vertex identifier. 
end_vid  ANYINTEGER 
Ending vertex identifier. 
directed  BOOLEAN 

heuristic  INTEGER 
(optional). Heuristic number. Current valid values 0~5. Default

factor  FLOAT 
(optional). For units manipulation. \(factor > 0\). Default 1 . See Factor 
epsilon  FLOAT 
(optional). For less restricted results. \(epsilon >= 1\). Default 1 . 
Returns set of (start_vid, end_vid, agg_cost)
Column  Type  Description 

start_vid  BIGINT 
Identifier of the starting vertex. 
end_vid  BIGINT 
Identifier of the ending vertex. 
agg_cost  FLOAT 
Aggregate cost of the shortest path from start_vid to end_vid . 