Select Layer By Location (Data Management)

Summary

Selects features based on a spatial relationship to features in another dataset or the same dataset.

Each feature in the Input Features parameter is evaluated using the features in the Selecting Features parameter. If the specified Relationship parameter value is met, the input feature is selected.

Learn more about Select By Location including image examples of relationships

Usage

• If the input is a feature class or dataset path, this tool will create and return a new layer with the result of the tool applied.

• The coordinate system in which the spatial relationship is evaluated can affect the result. Features that intersect in one coordinate system may not intersect in another.

  • This tool evaluates a spatial relationship in the coordinate system of the Input Features data source. Set the Output Coordinate System environment to Current Map [Layers] to use the same coordinate system as the current display.

• To select features based on their spatial relationships to other features in the same layer, see the examples in Select based on spatial relationship within the layer.

• The number of selected records will be listed in the geoprocessing history. Click Parameters > Count to access them. Additionally, the Get Count tool can be used to count the number of selected records. From Python, the number of selected records can also be accessed from the tool's Result object.

• When applying selections, a selection of zero records is possible. For example, using the Intersect option for the Relationship parameter when no features intersect, results in a selection of zero records. A geoprocessing tool using the layer as input will use no records from the input.

• For more information about using the 3D spatial relationship options Intersect 3D and Within a distance 3D, see Select By Location: 3D relationships.

• For the Relationship parameter, the Intersect (DBMS) option may provide better performance than the Intersect option when using enterprise geodatabase data; however, this option is only supported under specific conditions. If all conditions are met, the spatial operation will be performed in the enterprise geodatabase database management system (DBMS) rather than on the client. Consider the following when using this spatial relationship option:

  • The following requirements are necessary for the operation to run in the DBMS:
    • The Input Features and Selecting Features parameter values must be from the same enterprise geodatabase workspace and have the same spatial reference and geometry storage type.
    • The user connecting to the geodatabase must have privileges to create a view in the database where the feature classes are stored.
    • Supported geometry storage types for this option are ST_Geometry (IBM Db2, Oracle, PostgreSQL, and SAP HANA), PostGIS (PostgreSQL), SDO_GEOMETRY (Oracle), and Geometry and Geography (Microsoft SQL Server). See Geodatabase management for information about installing and configuring your DBMS as well as information about configuring the geometry storage type of your choice so it will be available for use. See the vendor documentation specific to your DBMS to determine what to expect for each geometry storage type. There may be storage limitations that will impact performance and scalability when running spatial operations.
    • If the feature classes in Oracle use ST_Geometry to store spatial data, you must configure the Oracle extproc to access ST_Geometry. See Configure the extproc to access ST_Geometry in Oracle for more information.
    • The Search Distance parameter is not set.
    • The Selection Type parameter value is New selection.
    • Existing selections prior to running the tool were made using a layer definition query, not a selection set.
  • The spatial operation is performed without applying an x,y tolerance during processing. Using an x,y tolerance is not supported in the DBMS. This may result in slightly different selections being returned compared to when the analysis is performed on the client with an x,y tolerance applied. See Feature class basics for more information about how an x,y tolerance is applied during client-side operations.

Parameters

Dialog

Label	Explanation	Data Type
Input Features	The features that will be evaluated using the Selecting Features parameter values. The selection will be applied to these features.	Feature Layer; Raster Layer; Mosaic Layer
Relationship (Optional)	Specifies the spatial relationship that will be evaluated. Intersect—The features in the input layer will be selected if they intersect a selecting feature. This is the default. Intersect 3D—The features in the input layer will be selected if they intersect a selecting feature in three-dimensional space (x, y, and z). Intersect (DBMS)—The features in the input layer will be selected if they intersect a selecting feature.This option applies to enterprise geodatabases only. The selection will be processed in the enterprise geodatabase DBMS rather than on the client when all requirements are met (see usage notes). This option may provide better performance than performing the selection on the client. Within a distance—The features in the input layer will be selected if they are within the specified distance (using Euclidean distance) of a selecting feature. Use the Search Distance parameter to specify the distance. Within a distance geodesic—This spatial relationship is the same as Within a distance except that geodesic distance is used rather than planar distance. Distance between features will be calculated using a geodesic formula that takes into account the curvature of the spheroid and correctly handles data near and across the dateline and poles. Choose this option if the data covers a large geographic extent or the coordinate system of the inputs is unsuitable for distance calculations. Use the Search Distance parameter to specify the distance. Within a distance 3D—The features in the input layer will be selected if they are within a specified distance of a selecting feature in three-dimensional space. Use the Search Distance parameter to specify the distance. Contains—The features in the input layer will be selected if they contain a selecting feature. Completely contains—The features in the input layer will be selected if they completely contain a selecting feature. Contains Clementini—This spatial relationship produces the same results as the Contains option except that if the selecting feature is entirely on the boundary of the input feature (no part is properly inside or outside), the feature will not be selected.Clementini defines the boundary polygon as the line separating inside and outside, the boundary of a line is defined as its end points, and the boundary of a point is always empty. Within—The features in the input layer will be selected if they are within a selecting feature. Completely within—The features in the input layer will be selected if they are completely within or contained by a selecting feature. Within Clementini—The result will be identical to the Within option result except that if the entirety of the feature in the input layer is on the boundary of the feature in the selecting layer, the feature will not be selected.Clementini defines the boundary polygon as the line separating inside and outside, the boundary of a line is defined as its end points, and the boundary of a point is always empty. Are identical to—The features in the input layer will be selected if they are identical (in geometry) to a selecting feature. Boundary touches—The features in the input layer will be selected if they have a boundary that touches a selecting feature. When the input features are lines or polygons, the boundary of the input feature can only touch the boundary of the selecting feature, and no part of the input feature can cross the boundary of the selecting feature. Share a line segment with—The features in the input layer will be selected if they share a line segment with a selecting feature. The input and selecting features must be line or polygon. Crossed by the outline of—The features in the input layer will be selected if they are crossed by the outline of a selecting feature. The input and selecting features must be lines or polygons. If polygons are used for the input or selecting layer, the polygon's boundary (line) will be used. Lines that cross at a point will be selected; lines that share a line segment will not be selected. Have their center in—The features in the input layer will be selected if their center falls within a selecting feature. The center of the feature is calculated as follows: for polygon and multipoint, the geometry's centroid is used; for line input, the geometry's midpoint is used.	String
Selecting Features (Optional)	The features in the Input Features parameter will be selected based on their relationship to the features from this layer or feature class.	Feature Layer
Search Distance (Optional)	The distance that will be searched. This parameter is only valid if the Relationship parameter is set to Within a distance, Within a distance geodesic, Within a distance 3D, Intersect, Intersect 3D, Have their center in, or Contains. If the Within a distance geodesic option is selected, use a linear unit such as kilometers or miles.	Linear Unit
Selection Type (Optional)	Specifies how the selection will be applied to the input and how it will be combined with an existing selection. This tool does not include an option to clear an existing selection; use the Select Layer By Attribute tool with the Selection Type parameter set to Clear the current selection to do that. New selection—The resulting selection will replace any existing selection. This is the default. Add to the current selection—The resulting selection will be added to an existing selection. If no selection exists, this is the same as the New selection option. Remove from the current selection—The resulting selection will be removed from an existing selection. If no selection exists, the operation will have no effect. Select subset from the current selection—The resulting selection will be combined with the existing selection. Only records that are common to both will remain selected. Switch the current selection—The selection will be switched. All records that were selected will be removed from the selection, and all records that were not selected will be added to the selection.The Selecting Features and Relationship parameters are ignored when this option is specified.	String
Invert Spatial Relationship (Optional)	Specifies whether the spatial relationship evaluation result or the opposite result will be used. For example, this parameter can be used to get a list of features that do not intersect or are not within a given distance of features in another dataset. Unchecked—The evaluation result will be used. This is the default. Checked—The opposite of the evaluation result will be used. If the Selection Type parameter is set, the reversal of the selection will occur before it is combined with existing selections.	Boolean

Derived Output

Label	Explanation	Data Type
Layer With Selection	The first input with selection applied.	Feature Layer; Mosaic Layer
Output Layer Names	A multivalue parameter including all inputs with selections applied. Use this output parameter in a model to connect to a tool with a multivalue input such as the Merge tool.	Feature Layer; Mosaic Layer
Count	The number of selected records. If there are multiple Input Features parameter values, the counts will be in the same order as the inputs.	Long

Python

arcpy.management.SelectLayerByLocation(in_layer, {overlap_type}, {select_features}, {search_distance}, {selection_type}, {invert_spatial_relationship})

Name	Explanation	Data Type
in_layer [in_layer,...]	The features that will be evaluated using the select_features parameter values. The selection will be applied to these features.	Feature Layer; Raster Layer; Mosaic Layer
overlap_type (Optional)	Specifies the spatial relationship that will be evaluated. INTERSECT—The features in the input layer will be selected if they intersect a selecting feature. This is the default. INTERSECT_3D—The features in the input layer will be selected if they intersect a selecting feature in three-dimensional space (x, y, and z). INTERSECT_DBMS—The features in the input layer will be selected if they intersect a selecting feature.This option applies to enterprise geodatabases only. The selection will be processed in the enterprise geodatabase DBMS rather than on the client when all requirements are met (see usage notes).This option may provide better performance than performing the selection on the client. WITHIN_A_DISTANCE—The features in the input layer will be selected if they are within the specified distance (using Euclidean distance) of a selecting feature. Use the search_distance parameter to specify the distance. WITHIN_A_DISTANCE_3D—The features in the input layer will be selected if they are within a specified distance of a selecting feature in three-dimensional space. Use the search_distance parameter to specify the distance. WITHIN_A_DISTANCE_GEODESIC—This spatial relationship is the same as WITHIN_A_DISTANCE except that geodesic distance is used rather than planar distance. Distance between features will be calculated using a geodesic formula that takes into account the curvature of the spheroid and correctly handles data near and across the dateline and poles. Choose this option if the data covers a large geographic extent or the coordinate system of the inputs is unsuitable for distance calculations. Use the search_distance parameter to specify the distance. CONTAINS—The features in the input layer will be selected if they contain a selecting feature. COMPLETELY_CONTAINS—The features in the input layer will be selected if they completely contain a selecting feature. CONTAINS_CLEMENTINI—This spatial relationship produces the same results as the CONTAINS option except that if the selecting feature is entirely on the boundary of the input feature (no part is properly inside or outside), the feature will not be selected.Clementini defines the boundary polygon as the line separating inside and outside, the boundary of a line is defined as its end points, and the boundary of a point is always empty. WITHIN—The features in the input layer will be selected if they are within a selecting feature. COMPLETELY_WITHIN—The features in the input layer will be selected if they are completely within or contained by a selecting feature. WITHIN_CLEMENTINI—The result will be identical to the WITHIN option result except that if the entirety of the feature in the input layer is on the boundary of the feature in the selecting layer, the feature will not be selected.Clementini defines the boundary polygon as the line separating inside and outside, the boundary of a line is defined as its end points, and the boundary of a point is always empty. ARE_IDENTICAL_TO—The features in the input layer will be selected if they are identical (in geometry) to a selecting feature. BOUNDARY_TOUCHES—The features in the input layer will be selected if they have a boundary that touches a selecting feature. When the input features are lines or polygons, the boundary of the input feature can only touch the boundary of the selecting feature, and no part of the input feature can cross the boundary of the selecting feature. SHARE_A_LINE_SEGMENT_WITH—The features in the input layer will be selected if they share a line segment with a selecting feature. The input and selecting features must be line or polygon. CROSSED_BY_THE_OUTLINE_OF—The features in the input layer will be selected if they are crossed by the outline of a selecting feature. The input and selecting features must be lines or polygons. If polygons are used for the input or selecting layer, the polygon's boundary (line) will be used. Lines that cross at a point will be selected; lines that share a line segment will not be selected. HAVE_THEIR_CENTER_IN—The features in the input layer will be selected if their center falls within a selecting feature. The center of the feature is calculated as follows: for polygon and multipoint, the geometry's centroid is used; for line input, the geometry's midpoint is used.	String
select_features (Optional)	The features in the Input Features parameter will be selected based on their relationship to the features from this layer or feature class.	Feature Layer
search_distance (Optional)	The distance that will be searched. This parameter is only valid if the overlap_type parameter is set to WITHIN_A_DISTANCE, WITHIN_A_DISTANCE_GEODESIC, WITHIN_A_DISTANCE_3D, INTERSECT, INTERSECT_3D, HAVE_THEIR_CENTER_IN, or CONTAINS. If the WITHIN_A_DISTANCE_GEODESIC option is selected, use a linear unit such as kilometers or miles.	Linear Unit
selection_type (Optional)	Specifies how the selection will be applied to the input and how it will be combined with an existing selection. This tool does not include an option to clear an existing selection; use the Select Layer By Attribute tool with the selection_type parameter set to CLEAR_SELECTION to do that. NEW_SELECTION—The resulting selection will replace any existing selection. This is the default. ADD_TO_SELECTION—The resulting selection will be added to an existing selection. If no selection exists, this is the same as the NEW_SELECTION option. REMOVE_FROM_SELECTION—The resulting selection will be removed from an existing selection. If no selection exists, the operation will have no effect. SUBSET_SELECTION—The resulting selection will be combined with the existing selection. Only records that are common to both will remain selected. SWITCH_SELECTION—The selection will be switched. All records that were selected will be removed from the selection, and all records that were not selected will be added to the selection.The select_features and overlap_type parameters are ignored when this option is specified.	String
invert_spatial_relationship (Optional)	Specifies whether the spatial relationship evaluation result or the opposite result will be used. For example, this parameter can be used to get a list of features that do not intersect or are not within a given distance of features in another dataset. NOT_INVERT—The evaluation result will be used. This is the default. INVERT—The opposite of the evaluation result will be used. If the selection_type parameter is set, the reversal of the selection will occur before it is combined with existing selections.	Boolean

Derived Output

Name	Explanation	Data Type
out_layer_or_view	The first input with selection applied.	Feature Layer; Mosaic Layer
out_layers_or_views	A multivalue parameter including all inputs with selections applied. Use this output parameter in a model to connect to a tool with a multivalue input such as the Merge tool.	Feature Layer; Mosaic Layer
count	The number of selected records. If there are multiple in_features parameter values, the counts will be in the same order as the inputs.	Long

Code sample

SelectLayerByLocation example 1 (Python window)

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

import arcpy
arcpy.management.SelectLayerByLocation("parcel_lyr", "have_their_center_in", 
                                       "c:/kamsack.gdb/city_limits")

SelectLayerByLocation example 2 (stand-alone script)

The following stand-alone script shows how to use the SelectLayerByLocation function in a workflow to extract features to a new feature class based on location and an attribute query.

# Description: Extract features to a new feature class based on a 
#              location and an attribute query

# Import arcpy and set path to data
import arcpy
arcpy.env.workspace = "c:/data/mexico.gdb"

# Make a layer and select cities that overlap the chihuahua polygon
chihuahua_cities = arcpy.management.SelectLayerByLocation('cities', 'INTERSECT', 
                                                          'chihuahua')

# From the previous selection, select a subset of cities that have 
# population > 10,000
arcpy.management.SelectLayerByAttribute(chihuahua_cities, 
                                        'SUBSET_SELECTION', 
                                        '"population" > 10000')

# If features matched criteria, write them to a new feature class
matchcount = int(arcpy.management.GetCount(chihuahua_cities)[0]) 

if matchcount == 0:
    print('no features matched spatial and attribute criteria')
else:
    arcpy.management.CopyFeatures(chihuahua_cities, 'chihuahua_10000plus')
    print('{0} cities that matched criteria written to {0}'.format(
        matchcount, chihuahua_10000plus))

SelectLayerByLocation example 3 (stand-alone script)

The following stand-alone script shows a variety of uses of the overlap_type parameter's WITHIN_A_DISTANCE and WITHIN_A_DISTANCE_GEODESIC options with the search_distance parameter.

# Description: Select features within a distance

# Import arcpy and set path to data
import arcpy

arcpy.env.workspace = r"c:\data\mexico.gdb"

arcpy.management.SelectLayerByLocation('cities', 'WITHIN_A_DISTANCE', 
                                       'chihuahua', '1.5 Miles')
arcpy.management.SelectLayerByLocation('cities', 'WITHIN_A_DISTANCE_GEODESIC', 
                                       'chihuahua', '200 Kilometers')

# When using WITHIN_A_DISTANCE, if distance units are not specified, the 
# distance value is assumed to be in the units of the input dataset's coordinate 
# system
arcpy.management.SelectLayerByLocation('cities', 'WITHIN_A_DISTANCE', 
                                       'chihuahua', '200')

# When using WITHIN_A_DISTANCE_GEODESIC, if distance units are not specified, 
# the distance value is assumed to be in meters
arcpy.management.SelectLayerByLocation('cities', 'WITHIN_A_DISTANCE_GEODESIC', 
                                       'chihuahua', '200')

Environments

Current Workspace, Output Coordinate System, Extent