Calculate Areas (Spatial Statistics)

Summary

Calculates area values for each feature in a polygon feature class.

Illustration

Usage

• The F_AREA field created in the Output Feature Class will be populated with values for the area of each polygon feature in square units of the Output_Coordinate_System.

• There are alternative methods for creating an Area field for polygon features including: Calculate_Field and the Geometry Calculator.

• The Output Feature Class is a copy of the Input Feature Class with the additional (or updated) F_AREA field containing polygon areas.

• This tool is useful for determining a weight for intra-zonal interaction.

• This tool can be used to calculate an Area value for a study area polygon. The Average Nearest Neighbor tool, for example, has an Area parameter.

Caution:

The F_AREA field is created in the Output Feature Class to store calculated Area values. If a field of this name already exists in the Input Feature Class, it will be overwritten in the Output Feature Class.

Caution:

When using shapefiles, keep in mind that they cannot store null values. Tools or other procedures that create shapefiles from non-shapefile inputs may store or interpret null values as zero. This can lead to unexpected results. See also Geoprocessing considerations for shapefile output.

Syntax

CalculateAreas_stats (Input_Feature_Class, Output_Feature_Class)

Parameter	Explanation	Data Type
Input_Feature_Class	The input polygon feature class.	Feature Layer
Output_Feature_Class	The output feature class. This feature class is a copy of the input feature class with field F_AREA added (or updated). The F_AREA field contains the polygon area.	Feature Class

Code Sample

CalculateAreas Example (Python Window)

The following Python Window script demonstrates how to use the CalculateAreas tool.

import arcpy
arcpy.env.workspace = "c:/data"
arcpy.CalculateAreas_stats("tracts.shp", "tracts_with_area_field.shp")

CalculateAreas Example (stand-alone Python script)

The following stand-alone Python script demonstrates how to use the CalculateAreas tool.

# Calculate AREA values
 
# Import system modules
import arcpy
 
# Local variables...
workspace = "C:/data"
input = "tracts.shp"
calculate_output = "tracts_with_area_field.shp"
 
try:
    # Set the current workspace (to avoid having to specify the full path to the feature classes each time)
    arcpy.env.workspace = workspace
 
    # Process: Calculate Areas...
    arcpy.CalculateAreas_stats(input, calculate_output)
 
except:
    # If an error occurred when running the tool, print out the error message.
    print arcpy.GetMessages()

Environments

Output Coordinate System, Current Workspace, Scratch Workspace, Qualified Field Names, Output has M values, Output has Z values, Default Output Z Value

Output Coordinate System

Feature geometry is projected to the Output Coordinate System prior to analysis.

Licensing Information

ArcView: Yes

ArcEditor: Yes

ArcInfo: Yes