Cost - Category

Warning

These are 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 ANY-INTEGER and ANY-NUMERICAL
    • 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.

General Information

Characteristics

The main Characteristics are:

  • Each function works as part of the family it belongs to.
  • It does not return a path.
  • Returns the sum of the costs of the resulting path(s) for pair combination of nodes in the graph.
  • 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 int 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 \(\infty\).
  • Let be the case the values returned are stored in a table, so the unique index would be the pair: (start_vid, end_vid).
  • Depending on the function and its parameters, the results can be symmetric.
    • The agg_cost of (u, v) is the same as for (v, u).
  • Any duplicated value in the start_vids or in end_vids are ignored.
  • The returned values are ordered:
    • start_vid ascending
    • end_vid ascending

See Also

Indices and tables