Cost - Category

Proposed

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 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