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Display geoprocessing results after they are created, intersect event layers, and create an event layer with a geoprocessing tool

Linear Referencing

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In this example you will see how to use the Overlay Route Events tool in ArcToolbox to intersect two event layers. The result will be a table that contains the injury accidents that happened on poor-quality pavement. All attributes from both inputs are maintained. First, however, you need to be sure that your geoprocessing results are automatically added to your display.

To do so, click Tools and click Options. Click the Geoprocessing tab and check the box to Add results of geoprocessing operations to the display. Click OK.

To intersect route events, open ArcToolbox, expand the Linear Referencing Tools, and open the Overlay Route Events tool. Click the Input Event Table drop-down list and click one of the event layers that you want to intersect. In this example it is the accident Events layer.
Because you selected an event layer, the Route Identifier Field, Event Type, and Measure Fields were set automatically. If you had selected an event table, you would be responsible for setting these parameters.
Click the Overlay Event Table dropdown arrow and click the other event layer that you want intersected. In this example it is the pavement Events line event layer. Click the Type of Overlay dropdown arrow and click INTERSECT. This will allow you to find the intersection of the two event layers. Type a name for the Output Event Table. In this example you’ll keep the remaining default settings for the tool. Click OK.

The result of the intersect operation is a table. In this example it is called AccPav.dbf. It is added to ArcMap and should be visible if you click the Source tab in the table of contents.

To view the results of the event intersection geographically, you need to create an event layer from them. In this example you see how to do that with a geoprocessing tool.

In an earlier segment you saw how to use the Add Route Events dialog box (from the Main menu) to display the accident and pavement condition information as layers in your map. Another way to do this is to use the Make Route Event Layer tool (from ArcToolbox). When called from ArcCatalog, this tool creates a temporary, in-memory layer. When executed in ArcMap, the in-memory layer is added to the display.

Because the event layers that were intersected had selections, only the selected features from each layer were intersected. The resulting layer shows where injury accidents occurred on poor quality pavement.

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