Feature Description

The overlay event table helps users extract more actionable information from existing event tables. Depending on the overlay method, it can be categorized into intersection overlay and union overlay. Based on event table types, it supports line-line overlay, line-point overlay, and point-point overlay. For more details, see Overlap Event Table.

Feature Entry

• On the Transport Analysis Tab -> Dynamic Segmentation group, click the Dynamic Segmentation button, then select Overlay Event Table from the dropdown menu.
• Toolbox -> Transport Analysis -> Dynamic Segmentation tools: Overlay Event Table; or drag this tool to the model builder window and double-click its icon.

Parameter Description

Three parameter groups must be specified for overlay event table: Input Event, Overlay Event, and Overlay Settings.

• Input Event: Configure parameters for the input event, including its datasource, event table, event type, route ID field, and measure fields. For line events, both From-Measure and To-Measure fields must be specified.
• Overlay Event: Configure parameters for the overlay event, including its datasource, event table, event type, route ID field, and measure fields. Line events require both From-Measure and To-Measure fields.
• Overlay Settings: Configure overlay parameters including overlay type and event tolerance.
  • Overlay Type: Select between Intersection or Union. For details, refer to Overlap Event Table.
  • Event Tolerance: Defines the tolerance for identifying zero-length line events. A tolerance of 1 means line events with length ≤1 are considered zero-length. Default tolerance relates to the dataset's coordinate system. See Tolerance Explanation.
  • Remove Zero-Length Events: Determines whether to exclude zero-length events. Available when: 1) Both input and overlay events are line events with intersection overlay; 2) One event is line type with union overlay. Check to remove zero-length events; uncheck to retain them.
  • Reserve the attribute fields of the event table: Determines whether to preserve attribute fields (excluding system fields) from the overlay event table in the result.
• Result Data: Configure result dataset parameters including route ID field, measure fields, target datasource, and output dataset name. Point-point overlay requires one measure field; line-point/line-line overlays require both From-Measure and To-Measure fields.
• Click Execute to run the operation after configuration.

Related Topics

• Overview of Event Table Analysis