Kruskal  Family of functions  pgRouting Manual (3.4)
Kruskal  Family of functions
Description
Kruskal’s algorithm is a greedy minimum spanning tree algorithm that in each cycle finds and adds the edge of the least possible weight that connects any two trees in the forest.
The main Characteristics are:

It’s implementation is only on undirected graph.

Process is done only on edges with positive costs.

When the graph is connected

The resulting edges make up a tree


When the graph is not connected,

Finds a minimum spanning tree for each connected component.

The resulting edges make up a forest.


The total weight of all the edges in the tree or forest is minimized.

Kruskal’s running time: \(O(E * log E)\)
Inner Queries
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
See Also
Indices and tables