Available with Advanced license.
Summary
Creates Thiessen polygons from point features.
Each Thiessen polygon contains only a single point input feature. Any location within a Thiessen polygon is closer to its associated point than to any other point input feature.
Illustration
Usage
This tool is used to divide the area covered by the input point features into Thiessen or proximal zones. These zones represent full areas where any location within the zone is closer to its associated input point than to any other input point.
Thiessen proximal polygons are constructed as follows:
- All points are triangulated into a triangulated irregular network (TIN) that meets the Delaunay criterion.
- The perpendicular bisectors for each triangle edge are generated, forming the edges of the Thiessen polygons. The location at which the bisectors intersect determine the locations of the Thiessen polygon vertices.
The outside boundary of the output Thiessen polygon feature class is the extent of the point input features plus an additional 10%. If the Extent environment is set to a specific extent window, this tool tool will use the environment setting to set its outside boundary.
Syntax
CreateThiessenPolygons(in_features, out_feature_class, {fields_to_copy})
Parameter | Explanation | Data Type |
in_features | The point input features from which Thiessen polygons will be generated. | Feature Layer |
out_feature_class | The output feature class containing the Thiessen polygons that are generated from the point input features. | Feature Class |
fields_to_copy (Optional) | Determines which fields from the input features will be transferred to the output feature class.
| String |
Code sample
CreateThiessenPolygons Example (Python Window)
The following Python window script demonstrates how to use the CreateThiessenPolygons tool in immediate mode.
import arcpy
arcpy.env.workspace = "C:/data/data.gdb"
arcpy.CreateThiessenPolygons_analysis("schools", "c:/output/output.gdb/thiessen1", "ALL")
CreateThiessenPolygons Example 2 (Stand-alone script)
The following stand-alone script demonstrates how to use the CreateThiessenPolygons function.
# Name: CreateThiessenPolygons_Example2.py
# Description: Creates Thiessen polygons
# Import system modules
#
import arcpy
from arcpy import env
# Set environment settings
#
env.workspace = "C:/data/data.gdb"
# Set local variables
#
inFeatures = "schools"
outFeatureClass = "c:/output/output.gdb/thiessen1"
outFields = "ALL"
# Execute CreateThiessenPolygons
#
arcpy.CreateThiessenPolygons_analysis(inFeatures, outFeatureClass, outFields)
Environments
Licensing information
- Basic: No
- Standard: No
- Advanced: Yes