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Connect

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Network functions connect


Contents

syntax

  1. connect(point_dataitem_org, point_dataitem_dest)
  2. connect(arc_polygon_dataitem, point_dataitem)

definition

The connect function connects nearby geometries. It has two variants:

  1. Both arguments are single point data items (syntax 1). This variant is used to find the nearest point_dataitem_dest for each point_dataitem_org. The function results in a relation for the domain unit of point_dataitem_org towards the domain of point_geom_dest.
  2. The first argument is an arc or polygon, the second argument is a point data item (syntax 2). The points of point_dataitem are connected to the nearest arc/polygon outline of the arc_polygon_dataitem. Cut points are added as (intermediate) points to the arc_polygon_dataitem The functions results in new domain unit with:
    • a UnionData subitem containing a new geometry, combining the original geometry of the arc_polygon_dataitem and the new connections to the point_dataitem.
    • a nr_OrgEntity subitem with a relation to the domain of the arc_polygon_dataitem (null for the new connections).


The figure illustrates this second variant. The dark green houses represent the point_dataitem, the light green lines the arc_polygon_dataitem. The resulting UnionData subitem of the connect function is presented with the blue lines.

description

The second variant is often used to build a network typology.

If the distance in the precision of the value type to the nearest point/arc/polygon is similar for multiple features, points are connected to the point/arc/polygon with the lowest index number.

In both variants, the first argument should contain unique geometries. Use the unique function to make a domain with unique geometries.

The connect_info function is used in the second variant to present information on the extra connections, e.g. the distance of each connection and the coordinates of the CutPoint on the connected arc/polygon.

applies to

  • data items point_dataitem_org, point_dataitem_dest, arc_polygon_dataitem and point_dataitem with fpoint or dpoint value type
  • data item arc_polygon_dataitem with composition type arc or polygon

conditions

The value type of all arguments must match.

since version

5.15

example

variant 1:

attribute <destination> destination_rel  (origin) := connect(destination/geometry, origin/geometry);
origin/geometry destination_rel
{401331, 115135} 0
{399476, 111803} 1
{399289, 114903} 2
{401729, 111353} 3
{398696, 111741} 1

domain origin, nr of rows = 5

destination/geometry
{401331, 115131}
{399138, 112601}
{398600, 114903}
{401729, 112156}

domain destination, nr of rows = 4


variant 2:

unit<uint32> location2road := connect(road/geometry, location/geometry);
road/geometry
{2 {399246, 112631}{398599, 111866}}
{3 {398599, 111866}{399495, 111924} {401801, 111524}}
{2 {401529, 114921}{398584, 114823}}

domain road, nr of rows = 3

location/geometry
{398600, 114903}
{398696, 111741}
{399138, 112601}
{399289, 114903}
{399476, 111803}
{401331, 115135}
{401729, 111353}
{401729, 112156}

domain location, nr of rows = 8

Location2Road/UnionData
{2: {399246, 112631} {399186, 112560}}
{2: {398599, 111866} {398688, 111872}}
{2: {401529, 114921} {401338, 114915}}
{2: {398600, 114903} {398603, 114824}}
{2: {398696, 111741} {398688, 111872}}
{2: {399138, 112601} {399186, 112560}}
{2: {399289, 114903} {399291, 114847}}
{2: {399476, 111803} {399468, 111922}}
{2: {401331, 115135} {401338, 114915}}
{2: {401729, 111353} {401760, 111531}}
{2: {401729, 112156} {401625, 111555}}
{2: {398603, 114824} {398584, 114823}}
{2: {398688, 111872} {399468, 111922}}
{2: {399186, 112560} {398599, 111866}}
{2: {399291, 114847} {398603, 114824}}
{3: {399468, 111922} {399495, 111924} {401625, 111555}}
{2: {401338, 114915} {399291, 114847}}
{2: {401760, 111531} {401801, 111524}}
{2: {401625, 111555} {401760, 111531}}

domain location2road, nr of rows = 19

see also

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