Tracking analysis is to establish network elements according to certain rules, which can be understood as establishing a "transparent layer" on the network layer and tracking the elements that need to be included in the transparent layer on the network. The data for tracking analysis must have a flow direction.
Tracing is to start from a node and search the network set that the node can reach according to certain conditions. For example, if pollution occurs somewhere in the water area, Trace Upstream analysis can be used to find out which waters the pollutants may come from, and Trace Down stream analysis can be used to find out the scope of the pollution source pollution.
The tracking analysis of SuperMap includes three kinds of analysis: tracking Shortest Path, Single Feature Tracing Analysis and Trace Multiple Elements.
The following table summarizes the feature support for trace analysis.
| Tracking analysis | Analysis Type | Analysis Type description | Number of elements |
| Trace the Shortest Path |
|
Shortest Path between two elements of Search Settings. Find the Shortest Path where the element to be analyzed reaches upstream. Find the Shortest Path that the feature to be analyzed reaches downstream. |
2 1 1 |
| Single Feature Tracing Analysis |
|
All network arc segments that flow up to the feature. Drillsdown to all network arcs that the feature can reach. Find the farthest source point of the feature and the arc segment, node and cost included in the minimum cost path to the source point. Find the farthest downstream sink from the element, and the arcs, nodes, and costs contained in the minimum-cost path to the sink. |
1 1 1 1 |
| Trace Multiple Elements |
|
Trace the upstream path that all analysis elements can reach together, against the direction of the network. Follow the downstream path that all analysis elements can reach together in the direction of the network. Tracks all arcs that are interconnected with the analysis feature. Tracks all arc segments that are disconnected from the analysis feature. Trace all the loops that are connected to the analysis element. |
Two or more nodes; one or more arc segments Two or more nodes; one or more arc segments One or more One or more One or more |
Related topics
Single Feature Tracing Analysis