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Lesson 2: Split a Polygon Feature
You can define rules that determine how properties are assigned after you
split a single feature into multiple pieces or merge multiple features into one.
In this lesson, you define split/merge rules for the Parcels feature. Then, you
split a parcel into two uneven pieces and use the rules you defined to assign
properties to each resulting parcel.
Exercise 1: Define split/merge rules
You can use the AutoCAD Trim and Break commands to split polygons.
However, the Split command has many advantages over those methods. A
split always results in a valid feature, and has special logic to deal with
attributes automatically.
With Split, you can set rules for the assignment of properties when you split
and merge geospatial features. You can use expressions for these rules.
For example, if you are splitting a parcel, you can base the land value of the
resulting parcels on a calculation that you define. You can also use automatic
calculations. For example, you can assign the average value of all merged
features to the resulting feature. You can divide the value of a feature evenly
among all its split features.
NOTE This exercise uses the map you created and modified in Exercise 1: Define
split/merge rules (page 286).
To create split/merge rules
1 The Data Table should still be open from the last exercise. If it is not, in
the Task Pane, switch to Display Manager. Select the Parcels layer and
click Table.
2 In the Data Table, click Options (at the bottom of the window) and select
Set Split And Merge Rules.
286 | Chapter 8 Tutorial: Working with Polygon Features