Summary
Overlays two event tables to create an output event table that represents the union or intersection of the input.
Usage
Line-on-line, line-on-point, point-on-line, and point-on-point event overlays can be performed.
The input and overlay events should be based on the same route reference.
The input tables can be any type of table that ArcGIS supports. The output table can be a dBASE file or a geodatabase table.
The output table can be displayed in ArcMap using the Make Route Event Layer tool or using the Display Route Events command in ArcMap.
If both the input and overlay event properties are type POINT, the output event properties must also be defined as type POINT.
If both the input and overlay event properties are type LINE, the output event properties must also be defined as type LINE.
If either the input or overlay event properties are type POINT, the output event properties must be defined as type POINT when an INTERSECT overlay is performed. The output event properties must be defined as type LINE when a UNION overlay is performed.
If both the input and overlay event properties are type POINT, only the points that have the exact same measure value are considered to intersect. There is no search tolerance.
An attribute index on the route identifier field speeds up the dynamic segmentation process. If you will be using the Output Event Table for dynamic segmentation, it is recommended that you choose to have an attribute index created.
Use the Make Table View tool prior to this tool to effectively reduce the number of events that will be processed.
If either the input or overlay events do not have an ObjectID field, use the Make Query Table tool prior to this tool to add a virtual ObjectID field.
Syntax
OverlayRouteEvents(in_table, in_event_properties, overlay_table, overlay_event_properties, overlay_type, out_table, out_event_properties, {zero_length_events}, {in_fields}, {build_index})
Parameter | Explanation | Data Type |
in_table | The input event table. | Table View |
in_event_properties | Parameter consisting of the route location fields and the type of events in the input event table.
| Route Measure Event Properties |
overlay_table | The overlay event table. | Table View |
overlay_event_properties | Parameter consisting of the route location fields and the type of events in the overlay event table. Route Identifier Field—The field containing values that indicate which route each event is along. This field can be numeric or character. Event Type—The type of events in the overlay event table (POINT or LINE).
From-Measure Field—A field containing measure values. This field must be numeric and is required when the event type is POINT or LINE. Note when the Event Type is POINT the label for this parameter becomes "Measure Field". To-Measure Field—A field containing measure values. This field must be numeric and is required when the event type is LINE. | Route Measure Event Properties |
overlay_type | The type of overlay to be performed.
| String |
out_table | The table to be created. | Table |
out_event_properties | Parameter consisting of the route location fields and the type of events that will be written to the output event table.
| Route Measure Event Properties |
zero_length_events (Optional) | Specifies whether to keep zero length line events in the output table. This parameter is only valid when the output event type is LINE.
| Boolean |
in_fields (Optional) | Specifies whether all the fields from the input and overlay event tables will be written to the output event table.
| Boolean |
build_index (Optional) | Specifies whether an attribute index will be created for the route identifier field that is written to the output event table.
| Boolean |
Code sample
OverlayRouteEvents example 1 (Python window)
import arcpy
arcpy.env.workspace = "C:/Data"
arcpy.OverlayRouteEvents_lr("accident.dbf", "rkey POINT mile", "pavecond.dbf",
"rkey LINE fmp tmp", "INTERSECT", "accpav",
"rkey POINT mile" )
OverlayRouteEvents example (stand-alone script)
The following Python script demonstrates how to use the OverlayRouteEvents function in a stand-alone Python script.
# NAme: OverlayRouteEvents_Example.py
# Description: Point-on-line INTERSECT overlay (both tables are dBASE)
# Import system modules
import arcpy
# Set workspace
arcpy.env.workspace = "C:/Data"
# Set local variables
in_tbl = "accident.dbf"
in_props = "rkey POINT mile" # reused as out event properties
ov_tbl = "pavecond.dbf"
ov_props = "rkey LINE fmp tmp"
out_tbl = "accpav"
# Execute OverlayRouteEvents
arcpy.OverlayRouteEvents_lr(in_tbl, in_props, ov_tbl, ov_props, "INTERSECT",
out_tbl, in_props)
OverlayRouteEvents example 2 (stand-alone script)
The following Python script demonstrates how to use the OverlayRouteEvents function in a stand-alone Python script using file geodatabase data.
# Name OverlayRouteEvents_Example2.py
# Description: Line-on-line UNION overlay (both tables are in a file geodatabase)
# Import system modules
import arcpy
# Set workspace
arcpy.env.workspace = "C:/Data/Pitt.gdb"
# Set local variables
in_tbl = "pavecond"
in_props = "rkey LINE fmp tmp" # reused as overlay and out event properties
ov_tbl = "pavetype"
out_tbl = "condtype"
# Execute OverlayRouteEvents
arcpy.OverlayRouteEvents_lr(in_tbl, in_props, ov_tbl, in_props, "UNION",
out_tbl, in_props, "NO_ZERO")
OverlayRouteEvents example 3 (stand-alone script)
The following Python script demonstrates how to use the OverlayRouteEvents function in a stand-alone Python script using enterprise geodatabase data.
# Name: OverlayRouteEvents_Example3.py
# Description: Point-on-line INTERSECT overlay (both tables are in enterprise geodatabase)
# Import system modules
import arcoy
# Set workspace
arcpy.env.workspace = "C:/MyProject/myConn.sde"
# Set local variables
in_tbl = arcpy.ValidateTableName("accident", wkspc)
in_props = "rkey POINT mile"
ov_tbl = arcpy.ValidateTableName("pavecond", wkspc)
ov_props = "rkey LINE fmp tmp"
out_tbl = "accpav"
out_props = "routekey POINT milepost" # names are changed for out table
# Execute OverlayRouteEvents
arcpy.OverlayRouteEvents_lr(in_tbl, in_props, ov_tbl, ov_props, "INTERSECT",
out_tbl, out_props)
OverlayRouteEvents example 4 (stand-alone script)
The following Python script demonstrates how to use the OverlayRouteEvents function in a stand-alone Python script using personal geodatabase data.
# Name: OverlayRouteEvents_Example4.py
# Description: Line-on-line UNION overlay (both tables are in a personal geodatabase)
# Import system modules
import arcpy
# Set workspace
arcpy.env.workspace = "C:/Data/Pitt.mdb"
# Set local variables
in_tbl = "pavecond"
in_props = "rkey LINE fmp tmp" # reused as overlay and out event properties
ov_tbl = "pavetype"
out_tbl = "condtype"
# Execute OverlayRouteEvents
arcpy.OverlayRouteEvents_lr(in_tbl, in_props, ov_tbl, in_props, "UNION",
out_tbl, in_props, "NO_ZERO")
Environments
Licensing information
- Basic: Yes
- Standard: Yes
- Advanced: Yes