pgr_pointsToDMatrix

Name

pgr_pointsToDMatrix - Creates a distance matrix from an array of points.

Synopsis

Create a distance symetric distance matrix suitable for TSP using Euclidean distances based on the st_distance(). You might want to create a variant of this the uses st_distance_sphere() or st_distance_spheriod() or some other function.

The function returns:

  • record - with two fields as describe here
    • dmatrix:float8[] - the distance matrix suitable to pass to pgrTSP() function.
    • ids:integer[] - an array of ids for the distance matrix. 
record pgr_pointsToDMatrix(pnts geometry[], OUT dmatrix double precision[], OUT ids integer[])

Description

Paramters

pnts:geometry[] - An array of point geometries.

Warning

The generated matrix will be symmetric as required for pgr_TSP.

History

  • New in version 2.1.0

Examples

select unnest(dmatrix) from pgr_pointsToDMatrix(
    pgr_texttopoints('2,0;2,1;3,1;2,2;4,1;4,2;2,3;3,2', 0)
) limit 8;
      unnest
------------------
                0
                1
  1.4142135623731
                2
 2.23606797749979
 2.82842712474619
                3
 2.23606797749979
(8 rows)

select ids from pgr_pointstodmatrix(
    pgr_texttopoints('2,0;2,1;3,1;2,2;4,1;4,2;2,3;3,2', 0)
);
        ids
-------------------
 {1,2,3,4,5,6,7,8}
(1 row)

See Also