Loading moving points with bearing data
This topic steps you through the process of loading moving points more accurately using bearing data. This kind of data is often sent by GPS receivers carried by pedestrians or mounted in vehicles.
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Make sure that the point features you are going to load have a numeric field named Bearing.
The data type must be numeric (double, float, long integer, or short integer). Also, the fields must be spelled exactly as shown here (Bearing and BearingTol). If the bearing or bearing tolerance information is available in a field with a different name or a nonnumeric data type, you will need to create a new field with the appropriate name and type, then transfer the values to the new field.
- Create another numeric field and name it BearingTol.
- Calculate the BearingTol field, specifying the acceptable bearing range or ranges.
The same bearing tolerance value can be calculated for all features, or a custom value can be calculated for each feature, perhaps based in part on GPS signal strength.
- Use the Load Locations dialog box or the Add Locations geoprocessing tool to load the points into a network analysis class. You can also set the search tolerance in either the dialog box or the tool dialog box.
It is important to be aware of the interplay between bearing tolerance and search tolerance. With a smaller bearing tolerance value, the likelihood of a point being located on a given edge decreases. This means that more points will tend to be located on the network farther away from their original geographic locations as compared to locating points without using bearing. Since the search tolerance settings limit how far away points can be located, you might want to set a smaller search tolerance so that they aren't located too far away.