Symmetrical Difference (Analysis)

Available with Advanced license.

Summary

Computes a geometric intersection of the input and update features, returning the input features and update features that do not overlap. Features or portions of features in the input and update features that do not overlap will be written to the output feature class.

Illustration

Symmetrical Difference tool illustration

Usage

  • The input and update feature class or feature layer must be of the same geometry type.

  • This tool honors the Parallel Processing Factor environment. If the environment is not set (the default) or is set to 0, parallel processing will be disabled. Setting the environment to 100 will enable parallel processing. Up to 10 cores will be used when parallel processing is enabled.

  • Attribute values from the input feature classes will be copied to the output feature class. However, if the input is a layer or layers created by the Make Feature Layer tool and a field's Use Ratio Policy is checked, then a ratio of the input attribute value is calculated for the output attribute value. When Use Ratio Policy is enabled, whenever a feature in an overlay operation is split, the attributes of the resulting features are a ratio of the attribute value of the input feature. The output value is based on the ratio in which the input feature geometry was divided. For example, if the input geometry was divided equally, each new feature's attribute value is assigned one-half of the value of the input feature's attribute value. Use Ratio Policy only applies to numeric field types.

    Caution:

    Geoprocessing tools do not honor geodatabase feature class or table field split policies.

  • This tool will use a tiling process to handle very large datasets for better performance and scalability. For more details, see Geoprocessing with large datasets.

  • This tool may generate multipart features in the output even if all inputs are single part. If multipart features are not desired, use the Multipart To Singlepart tool on the output feature class.

Parameters

LabelExplanationData Type
Input Features

The input feature class or layer.

Feature Layer
Update Features

The update feature class or layer. The geometry type must be the same as that of the input feature class or layer.

Feature Layer
Output Feature Class

The feature class to which the results will be written.

Feature Class
Attributes to Join
(Optional)

Specifies the attributes that will be transferred to the output feature class.

  • All attributesAll the attributes from the input features will be transferred to the output feature class. This is the default.
  • All attributes except feature IDsAll the attributes except the FID from the input features will be transferred to the output feature class.
  • Only feature IDsOnly the FID field from the input features will be transferred to the output feature class.
String
XY Tolerance
(Optional)

The minimum distance separating all feature coordinates (nodes and vertices) as well as the distance a coordinate can move in x or y (or both).

Caution:

Changing this parameter's value may cause failure or unexpected results. It is recommended that you do not modify this parameter. It has been removed from view on the tool dialog box. By default, the input feature class's spatial reference x,y tolerance property is used.

Linear Unit

arcpy.analysis.SymDiff(in_features, update_features, out_feature_class, {join_attributes}, {cluster_tolerance})
NameExplanationData Type
in_features

The input feature class or layer.

Feature Layer
update_features

The update feature class or layer. The geometry type must be the same as that of the input feature class or layer.

Feature Layer
out_feature_class

The feature class to which the results will be written.

Feature Class
join_attributes
(Optional)

Specifies the attributes that will be transferred to the output feature class.

  • ALLAll the attributes from the input features will be transferred to the output feature class. This is the default.
  • NO_FIDAll the attributes except the FID from the input features will be transferred to the output feature class.
  • ONLY_FIDOnly the FID field from the input features will be transferred to the output feature class.
String
cluster_tolerance
(Optional)

The minimum distance separating all feature coordinates (nodes and vertices) as well as the distance a coordinate can move in x or y (or both).

Caution:

Changing this parameter's value may cause failure or unexpected results. It is recommended that you do not modify this parameter. It has been removed from view on the tool dialog box. By default, the input feature class's spatial reference x,y tolerance property is used.

Linear Unit

Code sample

SymDiff example (Python window)

The following Python window script demonstrates how to use the SymDiff function in immediate mode.

import arcpy
arcpy.env.workspace = "C:/data"
arcpy.SymDiff_analysis("climate.shp", "elevlt250.shp", "C:/output/symdiff.shp", 
                       "ALL", 0.001)
SymDiff example 2 (stand-alone script)

The following stand-alone script demonstrates how to use the SymDiff function.

# Name: SymDiff_Example2.py
# Description: Create symmetrical difference between input and update features
 
# Import system modules
import arcpy
 
# Set environment settings
arcpy.env.workspace = "C:/data"
 
# Set local variables
inFeatures = "climate.shp"
updateFeatures = "elevlt250.shp"
outFeatureClass = "C:/output/symdiff.shp"
clusterTolerance = 0.001
 
# Execute SymDiff
arcpy.SymDiff_analysis(inFeatures, updateFeatures, outFeatureClass, "ALL",
                       clusterTolerance)

Licensing information

  • Basic: No
  • Standard: No
  • Advanced: Yes

Related topics