Centroid_or_mid

Geometric functions centroid_or_mid

syntax

• centroid_or_mid(polygon_data_item)

definition

centroid_or_mid(polygon_data_item) results in a point data item with

1. the centroid if it is located in the polygon
2. or else the mid-point of the polygon_dataitem argument.

description

The centroid_or_mid function results in the centroid if it is located within the polygon or else in the mid of the polygon. This means the result of the centroid_or_mid is always located within the polygon.

In the image above the centroid is not located within the polygon. The centroid_or_mid function will still result in a point within the polygon.

applies to

data item polygon_dataitem with fpoint or dpoint value type and composition type polygon.

example

attribute<point_rd> centroid_or_mid (district) := centroid_or_mid(district/geometry);

district/geometry	centroid_or_mid
{21 {403025, 113810}{4	{402955, 113049}
{17 {400990, 113269}{4	{401159, 112704}
{19 {401238, 115099}{4	{401268, 114017}

domain district, nr of rows = 3

see also

• centroid