Advanced AH Two-Point Trace
Description
Traces between upstream and downstream points using Arc Hydro Trace by AH Attribute base functionality. In addition, it selects resulting hydro junction features and if provided, additional related features to hydro junctions. Review help for Trace by AH Attribute for description of base Arc Hydro attribute tracing functionality. Hydro junction feature class must have HydroID and NetID fields populated. NetID value for a junction is HydroID of the underlying tracing layer feature that the junction resides on. It is used for junction selection once trace returns selected trace features (attribute selection). If optional Relate layer is provided, it must have attribute JunctionID populated that contains the HydroID of the junction the feature is related to. Related layer can be of any feature type (point, line, or polygon).
Usage
Parameters
| Direction | Type | Parameter Name | Data Type | Dialog Reference |
|---|---|---|---|---|
| Input | Required | Upstream Point | Feature Set | Upstream point to define the trace. It should be placed on or near the trace feature to make sure correct selection is made. The point needs to be within "Search Distance" from a trace feature to be used in tracing.Point can be defined either interactively or as a feature class. If defined interactively, it will be stored in temporary feature class "ts_start_points" in scratch geodatabase. Interactive points are transient in nature. Next run of the tool will overwrite it. |
| Input | Required | Downstream Point | Feature Set | Downstream point to define the trace. It should be placed on or near the trace feature to make sure correct selection is made. The point needs to be within "Search Distance" from a trace feature to be used in tracing.Point can be defined either interactively or as a feature class. If defined interactively, it will be stored in temporary feature class "ts_start_points" in scratch geodatabase. Interactive points are transient in nature. Next run of the tool will overwrite it. |
| Input | Required | Input Trace Layer | Feature Layer | Feature class to be used for tracing. Any type of feature class can be used to trace through as long as it has appropriate fields identifying downstream elements, typically, [HYDROID, NextDownID] or [From_Node, To_Node]. |
| Input | Optional | Search Distance | Linear Unit | Distance used to perform spatial selection of trace features used as start and barrier features. To precisely control selection of trace features, best practice is to snap the point onto the trace feature and set the "Search Distance" to 0. Larger search distance can be used to make multiple feature selections with a single point. |
| Input | Optional | Snap Input Points | Boolean | Controls whether to snap (move) input points to trace features. Note that this option does not impact execution of feature selection - that is controlled by the search distance: |
| Input | Required | Hydro Junction Layer | Feature Layer | Hydro junctions related to the trace layer. Must have field NetID populated with the HydroID of the trace layer feature hydro junction is related to. |
| Input | Optional | Related Layer (Optional) | Feature Layer | Must have field JunctionID populated with the HydroID of the hydro junction the feature is related to. It can be of any feature type (point, line, or polygon). |