Available with Location Referencing license.
The information model for ArcGIS Roads and Highways includes multiple feature classes. Since measures and their precision are critical to the accuracy of any linear referencing method (LRM), the spatial reference, tolerance, and resolution settings for all of these feature classes must align. This ensures that geometry and measures for routes, events, and intersections are correct in a linear referencing system (LRS) and remain in alignment. If any of the centerline, calibration point, redline, network, event, or intersection feature classes are modeled before they are registered with the LRS, ensure that the tolerance and resolution settings match. Use the information in the following table to assist you with determining the correct spatial reference, tolerance, and resolution settings to use for the centerline, calibration point, redline, network, event, and intersection feature classes in your LRS.
| Feature class | Spatial reference | x,y-tolerance | x,y resolution | z-tolerance | z resolution | m-tolerance | m resolution | Additional information |
|---|---|---|---|---|---|---|---|---|
Source Route data used for loading | NAD 1983 UTM Zone 12N | 0.001 meters | 0.0001 meters | 0.001 meters | 0.0001 meters | 0.001 meters | 0.0001 meters | The spatial reference and x,y- and z-tolerance and resolution values should be applied to the centerline, calibration point, and redline feature classes. |
Centerline | Same as source routes, NAD 1983 UTM Zone 12N | Same as source routes, 0.001 meters | Same as source routes, 0.0001 meters | Same as source routes, 0.001 meters | Same as source routes, 0.0001 meters | Not m-enabled | Not m-enabled | The spatial reference, x,y-tolerance and resolution, and z-tolerance and resolution should match that of the source routes used for loading data. |
Calibration Point | Same as centerline, NAD 1983 UTM Zone 12N | Same as centerline, 0.001 meters | Same as centerline, 0.0001 meters | Same as centerline, 0.001 meters | Same as centerline, 0.0001 meters | Not m-enabled | Not m-enabled | The spatial reference, x,y-tolerance and resolution, and z-tolerance and resolution should match the centerline feature class. |
Redline | Same as centerline, NAD 1983 UTM Zone 12N | Same as centerline, 0.001 meters | Same as centerline, 0.0001 meters | Not z-enabled | Not z-enabled | Not m-enabled | Not m-enabled | The spatial reference and x,y-tolerance and resolution should match the centerline feature class. |
Network | Same as centerline, NAD 1983 UTM Zone 12N | Same as centerline, 0.001 meters | Same as centerline, 0.0001 meters | Same as centerline, 0.001 meters | Same as centerline, 0.0001 meters | Depends on unit of measure for the network. If meters, 0.001 meters. If kilometers, 0.000001 km. If miles, 0.000000621369949 miles. | Depends on unit of measure for the network. If meters, 0.0001 meters. If kilometers, 0.0000001 km. If miles, 0.000000062136995 miles. | The spatial reference, x,y-tolerance and resolution, and z-tolerance and resolution should match the centerline. The m-tolerance and resolution are based on the units of measure of the spatial reference for the network feature class and the units of measure for the LRM being used. See the explanation in the paragraph below. |
Event | Same as network, NAD 1983 UTM Zone 12N | Same as network, 0.001 meters | Same as network, 0.0001 meters | Same as network, 0.001 meters | Same as network, 0.0001 meters | Same as network | Same as network | The spatial reference, x,y-tolerance and resolution, z-tolerance and resolution, and m-tolerance and resolution should match the network to which the event will be registered. |
Intersection | Same as network, NAD 1983 UTM Zone 12N | Same as network, 0.001 meters | Same as network, 0.0001 meters | Same as network, 0.001 meters | Same as network, 0.0001 meters | Same as network | Same as network | The spatial reference, x,y-tolerance and resolution, z-tolerance and resolution, and m-tolerance and resolution should match the network to which the intersections will be registered. |
Note:
The values shown in the table above are examples. ArcGIS Roads and Highways supports the use of any spatial reference supported for use with ArcGIS. The tolerance and resolution settings can be different than the values in the example; however, they must remain in alignment between feature classes to ensure correctly calibrated routes. Although any tolerance value that is at least twice as large as the resolution is supported, consider a tolerance at least ten times as large as the resolution for your feature classes that participate in the LRS for best performance.
The spatial reference, x,y-tolerance and resolution, and z-tolerance and resolution of the centerline feature class should match that of any source routes that will be loaded into the network. These settings are propagated to networks, events, and intersections in the LRS.
The calibration point and redline feature classes should have the same spatial reference, x,y-tolerance and resolution, and z-tolerance and resolution as the centerline feature class.
Networks share the same spatial reference, x,y-tolerance and resolution, and z-tolerance and resolution as the centerline feature class. The m-tolerance and resolution for the network will be based on the units of measure of the spatial reference for the network feature class and the units of measure for the LRM being used. If the units of measure are different, you will need to derive the m-tolerance and resolution from the x,y-tolerance and resolution.
For example, suppose your network feature class has a spatial reference in meters with an x,y-tolerance of 0.001 meters and an x,y-resolution of 0.0001 meters. If the units of measure for the LRM are in meters, the m-tolerance would be 0.001 and the m resolution would be 0.0001. However, if the units of measure for the LRM are in kilometers, the x,y-tolerance and resolution values would need to be converted from meters to kilometers for the m-tolerance and resolution. In this example, the m-tolerance would be 0.000001, and the resolution would be 0.0000001.
Event feature classes will share the same spatial reference, and x,y-, z-, and m-tolerance and resolution as the network to which the event is registered.
Intersection feature classes will share the same spatial reference and x,y-tolerance and resolution as the network of which the intersection is part.
Learn more about feature class tolerance and other properties