Knowledge Base - Technical Articles


Technical Article   HowTo:  Find the centroid of polygons using Calculate Geometry

Article ID: 32988
Software:  ArcGIS - ArcEditor 9.2, 9.3, 9.3.1, 10 ArcGIS - ArcInfo 9.2, 9.3, 9.3.1, 10 ArcGIS - ArcView 9.2, 9.3, 9.3.1, 10 ArcGIS for Desktop Advanced 10.1 ArcGIS for Desktop Standard 10.1 ArcGIS for Desktop Basic 10.1
Platforms: N/A

Summary

Instructions provided describe how to find the centroid of polygons using Calculate Geometry.

Procedure

  1. In the map document, open the attribute table for the polygon feature class.
  2. In the attribute table, navigate to Table Options > Add Field and add two new fields of type Double. Name one 'Latitude' and the other 'Longitude'.
  3. Right-click the Longitude field and select Calculate Geometry.
  4. In the Calculate Geometry dialog box, select 'X Coordinate of Centroid' from the Property drop-down menu. Click OK.
  5. Right-click the Latitude field and select Calculate Geometry.
  6. In the Calculate Geometry dialog box, select 'Y Coordinate of Centroid' from the Property drop-down menu. Click OK.
  7. Export to a table.
    A. In the attribute table, select Table Options > Export.
    B. Specify a name and location for the new table.
  8. Make an XY Event layer.
    A. Navigate to ArcToolbox > Data Management Tools > Layers and Table Views > Make XY Event Layer.
    B. Add the new table (from step 7) as the XY Table.
    C. For the X Field, select the Longitude field.
    D. For the Y Field, select the Latitude field.
    E. Name the new event layer.
    F. Select the spatial reference or coordinate system.
    G. Click OK.
  9. (Optional)
    Export the Event Layer to a shapefile by right-clicking the layer and navigating to Data > Export Data.

Related Information

  • Calculate the centroid of a polygon
    Instructions provided describe how to use a VBA script in the Field Calculator to calculate latitude and longitude values for polygon centroids.

Created: 5/2/2007
Last Modified: 7/9/2013

If you would like to post a comment, please login