Euclidean Allocation / Voronoi Diagram / Thiessen Polygons
Open Table of Contents ToolBox Implementation
Derives the catchment areas of the input features (Sources). Each cell of the output raster will have the value of the closest (based on straight line distance) Source.

Inputs:

  • A point, polyline or polygon dataset (Sources).
  • The cell size of the output raster.
  • Source ID field. The values from this field will be allocated to the cells of the output raster.

Outputs:

  • An integer raster. Each cell will have as a value the ID of the closest input point (Source). The extent of the output is equal to the extent of the input feature class.

Example:

Notes:

  • Initially the name of the output raster defines the raster format
    • no extension specified - ESRI binary GRID
    • .img extension (for example raster1.img) - ERDAS IMAGINE image.
    • .tif extension (for example raster1.tif - Tagged Image File Format (TIFF) image.
  • The initial output raster format can be changed by selecting the desired output in the dialog.
  • Currently only file based rasters are supported. Rasters cannot be stored in a GeoDatabase. After you get the desired result, you can export the raster to a GeoDatabase using the standard ArcGIS tools.
  • The input feature class must be in a projected coordinate system.
  • The result raster can be easily converted to a polygon feature class using the standard ArcGIS Raster To Polygon tool
  • The attributes can be transferred to the polygons by joining the Raster Attribute Table to the polygons using GRID_CODE field of the feature class and the Value field of the raster attribute table.

ToolBox implementation

Command line syntax

ETS_GPVoronoi <Input Features>  <Out Raster> < ID Field> < Cell Size>

Parameters

Expression Explanation
<Input Features> A Point, Polyline or Polygon feature layer or feature class
<Out Raster> A String - the full name of the output raster (A raster with the same full name should not exist). The output raster type depends on the extension of the output file(see Notes above)
 < ID Field> A String representing the name of the field in the input point feature class to be used as point ID.
<Cell Size> A Double representing the cell size of the output raster.

Scripting syntax

ETS_GPVoronoi (Input Features, Out Raster, ID Field, Weight Field, Cell Size)

See the explanations above:
<> - required parameter
{} - optional parameter

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Copyright: Ianko Tchoukanski