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The next topics on this page describe the point data item. The point function is described on the point() page.

In the GeoDMS point data items are used for:

Vector data

The feature attribute of point vector data always refers to one coordinate for each element in the domain.

Vector data if often read from a shape file, but x and y attributes can also easily be read as numeric attributes from other data sources and combined with a point function to a feature attribute, as in the next example.

unit<uint32> residence
:   StorageName = "=System/DbName"
,   SqlString         = "SELECT * FROM Residences ORDER BY id"
   attribute<coord_rd> x;
   attribute<coord_rd> y;
   attribute<point_rd>  geometry := point(x, y, point_rd);

The x and y attributes are read from the data source with as values unit coord_rd. The geometry data item combines both x and y coordinate with the point function to create a two dimensional data item of coordinates. The values unit of this geometry attribute is point_rd, defining the coordinate system.

Subitems of the location item can be configured to define multiple visualisation styles.

Grid data

As the nature of Grid data is two-dimensional, the identification of a grid cell in a Grid Domain is also two-dimensional.

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