Network Analysis Environment Settings

Through theTransport Analysis tab -> Route Analysis group -> Environment Settings function, you can centrally manage all global parameters of network analysis. However, the parameters in the panel can only be set when a network dataset is loaded in the current map.

Toolbar

The toolbar of the Environment Settings panel organizes functions for the network analysis environment.

  • Styles: You can set display styles individually for different graphic elements in network analysis as needed, including points (e.g., stops, barrier points), lines (e.g., result path), areas (e.g., service areas), and text labels (e.g., prompts). For details, refer to the Styles page.
  • Traffic Rules Settings: Used to configure traffic rules for network arcs. You can set passability attributes for road segments, including: two-way passability, forbid to pass, forward value, or backward value. For details, refer to the Traffic Rules Settings page.
  • Turn Table Settings: Used to manage turn tables required for network analysis, including Create Turn Table and Set Turn Table.
  • Weight Settings: Weight settings include update edge weight and node weight. Update Edge Weight is used to set the forward/reverse weight of an arc and whether the arc is a barrier edge. Update Node Weight is used to set the turn weight at a node and whether the node is a barrier point.
  • Analysis Bounds Settings: Used to set the area for network analysis. After setting, the system will load only the network data within this area, thereby improving analysis efficiency. For details, refer to the Analysis Area Settings page.
  • Trace Analysis Network Modeling: Used to set parameters for trace analysis, including the node ID field and edge ID field of the facility network, whether to create flow direction, whether to create levels, etc. For details, refer to the Trace Analysis Network Modeling page.
  • Check Loops: Used to check whether there are loops in the network dataset. For details, refer to the Check Loops page.

Network Dataset Information

  • Select Dataset: When multiple network datasets exist, select the target network layer from this drop-down list to apply the environment settings.
  • Dataset Information: Displays the basic information of the dataset during network analysis.
    • Network Analysis Basic Parameters:
      • Network Dataset: Displays the name of the network dataset for which environment settings are currently being performed. It cannot be edited.
      • Forward/Backward Weight Field: Select a field from the right drop-down list as the forward/backward weight field of the network dataset arcs. Any field of the current network layer can be selected as the weight field.

        The weight field represents the cost value from one network node to another. In practical applications, fields such as distance, time, or cost can be used as weight fields. For example, to calculate from point A to point B, you can use a time field as the weight field, and then use the path analysis function in network analysis to calculate the optimal path analysis between point A and point B. The forward weight refers to the cost from the start node to the end node of an arc, while the backward weight refers to the cost from the end node to the start node of the arc. The settings of these two fields can be the same (e.g., when using length as the weight field) or different (e.g., when setting time as the weight field, because the time to travel from the start to the end of an arc and from the end to the start of the same arc may be different within the same period).

        The weight field supports direct input of expressions, or you can select "Expression..." and use the "SQL Expression" dialog to define an expression. For information on how to use SQL Expression, refer to the SQL Expression page.

      • Node ID Field: Select a field from the right drop-down list that uniquely identifies each node in the network dataset. You can select a field from the point dataset of the network dataset as the marking field. The application uses the SMNODEID field as the node ID field by default.
      • Edge ID Field: Select a field from the right drop-down list that uniquely identifies each arc in the network dataset. You can select a field from the line dataset of the network dataset as the marking field. The application uses SMEDGEID as the edge ID field by default.
      • Start/End Node ID: Select a field from the right drop-down list that identifies the start/end node of the network dataset. You can select a field from the line dataset of the network dataset as the marking field. The application uses SMTNODE as the start/end node ID by default.
      • Edge Filter: Set the arcs to be filtered out during analysis. Only arc objects that satisfy this expression will be considered during network analysis. You can directly enter an expression, or select Expression... and use the SQL Expression dialog to define an expression. For information on how to use SQL Expression, refer to the SQL Expression page.
      • Traffic Rules: Set whether to enable rules during analysis. You can configure traffic rules as needed. The application disables this by default. For information on how to set traffic rules, refer to the Setting Traffic Rules page.
      • Turn Table: Set whether to enable the turn table during analysis. You can configure turn table settings as needed. The application disables this by default. For information on how to create and set turn tables, refer to the Turn Table page.
      • Tolerances: The distance from a point to an arc. The default value is 0. If a node is within the tolerance range, it participates in the analysis; otherwise, it is excluded.
    • Result Settings:
      • Result Datasource: The datasource where network analysis results are saved by default. Subsequent network analysis results will be saved under this datasource by default. The default is the datasource where the current network dataset resides.
      • Edge Info Field: A field that provides arc information, such as the road name field. It can be used to generate route guidance.
      • Node Info Field: A field that provides node information, such as the bus stop name field. It can be used to generate route guidance.
    • Trace Analysis:
      • Flow Direction Field: A prerequisite for trace analysis. A flow direction field needs to be specified to indicate the flow direction of arcs.