Nearest point

Dialog box

The nearest point operation requires a point map as input and returns a raster map as output. Each pixel in the output map is assigned the class name, identifier or value of the nearest point, according to Euclidean distance. This operation is also known as Nearest neighbour or Thiessen Map.

Dialog box options:

Input point map:

Select an input point map. Open the list box and select the desired input map, or drag a point map directly from the Catalog into this box. Any map with a class, ID, value or bool domain is accepted; you can also select an attribute from a linked attribute table.

Use spherical distance:

Select this check box to calculate with spherical distances, i.e. distances are calculated over the sphere using the projection of the coordinate system of the georeference of the output raster map. It is advised to select this option in case your map covers a relatively large area, or when you are working in LatLon coordinates. For more information, see Nearest point : functionality/algorithm.

Clear this check box to calculate with planar (Euclidean) distances.

Output raster map:

Type a name for the output raster map that will contain, for each pixel, the class name, identifier, or value of the nearest point.

Georeference:

Select the name of an existing georeference or create a new georeference (click the create button ).

Value range:

In case the output map uses a value domain, accept the default value range, or specify your own range of possible values in the output map.

Precision:

In case the output map uses a value domain, accept the default precision of output values, or specify your own precision.

Description:

Optionally, type a description for the output map. The description will appear in the status bar of the Main window when moving the mouse pointer over the map in a Catalog, and in the title bar of a map window when the output map is displayed. If no description is supplied, the output map will use its own definition as description.

When you click the Show button, the dependent output map will be defined, calculated and shown. When you click the Define button, the dependent output map will only be defined; if necessary, the map will be calculated later, for instance when the map is opened to be displayed.

See also: