Tolerance and resolution settings for the LRS

Available with Location Referencing license.

The data model for ArcGIS Pipeline Referencing includes multiple feature classes. Because measures and their precision are vital 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. The example table below shows the information used 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 classSpatial referencex,y-tolerancex,y resolutionz-tolerancez-resolutionm-tolerancem resolutionAdditional 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

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.

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. Pipeline Referencing 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 10 times as large as the resolution for 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 need to derive the m-tolerance and resolution from the x,y-tolerance and resolution.

Note:

The m-tolerance of the LRS Network is used to determine the number of decimal places used in calculations of measures and related operations in the LRS. For example, if the m-tolerance is 0.001, calculations will occur at the 3rd decimal place. If the m-tolerance is 0.005, calculations will also occur at the 3rd decimal place. The m-tolerance is also used to determine whether two values are equal. If the difference between two measure is less than the m-tolerance, the two values are considered equal. If the difference is larger than the m-tolerance, the values are considered different.

For example, 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 meters, the m-tolerance is 0.001 and the m-resolution is 0.0001. However, if the units of measure for the LRM are kilometers, the x,y-tolerance and resolution values must be converted from meters to kilometers for the m-tolerance and m-resolution. In this example, the m-tolerance would be 0.000001, and the m-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