Trace Analysis Network Modeling

Feature Description

Creates and sets the flow direction for trace analysis.

When creating a flow direction field, you first need to specify sources and sinks in the trace network, and store this information in a field. The flow direction field is calculated based on the source-sink information field. You can also create a stream level field to store watercourse hierarchy.

Steps

  1. In the Environment Settings window, click the Create Flow Direction drop-down button -> Trace Analysis Network Modeling button.
  2. In the Trace Analysis Network Modeling dialog, select the network dataset requiring flow direction setup, then configure its node ID field, edge ID field, start node ID, and end node ID.
  3. Check the Create Flow Direction checkbox to specify the node type field name and flow direction field. The default generated node type field is NodeType, which stores imported node types: 0 indicates common nodes, 1 indicates sources, and 2 indicates sinks.
  4. To create stream levels, check the Create Level checkbox and name the level field.
  5. Set loop validity. This parameter only affects networks with level fields. Checking Loop Valid means considering loops during trace analysis, allowing result paths to contain cycles; otherwise, looped routes will be excluded.
  6. Click the Import button in the Source-Sink Settings panel to open the Import Node dialog for configuring source/sink import parameters.
  7. After successful import, directly click the Node Type column to modify node types. Supported types include common nodes, sources, and sinks (default: source).
  8. The toolbar in the Trace Analysis Network Modeling dialog provides common operations for managing sources/sinks: import/export nodes, select all, invert selection, delete, and batch modify node types.
    • Import: Import source/sink data with parameter settings.

      Datasources: The datasource containing source/sink data.

      Dataset: The dataset storing source/sink points.

      Node Type Field: If node types are predefined in a field, select this field to import type information automatically.

      Filter: Import nodes satisfying the filter condition. Enter an expression directly or click the browse button to define it using the SQL Expression dialog. For SQL usage, see the SQL Expression Query page.

      Import by Associated Node: When checked, uses an association field for node import. To use network analysis stations as network nodes, select a point dataset field that correlates with the network's internal node ID field.

      Node ID Field: Must match the node ID field in the Environment Settings dialog. Available only when Import by Associated Node is checked.

    • Export: Export source/sink information as a point dataset.

      Datasources: Target datasource for exported data.

      Dataset: Name of the exported point dataset.

      Node Type Field: Field name for storing node types in the exported dataset.

      Node ID Field: Field name for storing node IDs in the exported dataset.

    • Select All: Select all nodes in the source-sink list.
    • Select Reverse: Invert node selection in the source-sink list.
    • Delete: Remove selected nodes from the source-sink list.
    • United Value Settings: Batch modify node types for selected entries. Click this button to open a dialog where you can uniformly set node types to source, sink, or common node via a dropdown.
  9. After completing parameter settings, click OK to finish trace analysis network modeling.
Caution:

If the network dataset contains only one subnet, it supports single-source-single-sink flow direction calculation. For datasets with multiple disconnected subnets, multi-source-multi-sink flow direction calculation is supported.