Pitney Bowes MapInfo Professional - Manual (Page 298)

Clipping a Region of a Map
You can use Map > Set Clip Region to isolate a region of a map for display and/or printing. The clipped
region may be a pre-defined map region, such as a state, or you can use a drawing tool to define a
region. Use the Select tool to select a pre-defined region or a region that you defined. Thematic maps
and seamless layers, labels, and points displayed on the map will be included in the clipped region.
• For specific instructions, see Clipping a Region of a Map and Setting Clip Region Options on the Fly
in the Help System.
To toggle between the map and the clipped region, you may find it useful to use the Clip Region On /Off
command.
To clip a raster image, use an object created in the cosmetic layer, or an object from an existing
vector layer. Note:
• For specific instructions, see Saving a Clipped Region of a Map in the Help System.
Overview of Combining Map Objects
When you choose Combine, MapInfo Professional performs two operations:
1. MapInfo Professional geographically combines the selected objects. The new object represents the
geographic union of the original objects. Therefore, if you select two adjacent region objects and
choose Combine, MapInfo Professional combines the regions into a single object, and the border
between the regions disappears.
2. MapInfo Professional performs data aggregation. Data aggregation is a process where MapInfo
Professional calculates what the column values for the new object should be, based on sums or
averages of the values of the original objects.
Perhaps you have a table of sales territories, and the table contains demographic information about the
number of households per territory. Using the Combine command, you can combine two of the sales
territories into one, large territory. In the same operation, MapInfo Professional also can calculate the
number of households in the new territory by adding the values from each of the original territories.
Combining Objects with Set Target
The Combine operation can work in conjunction with the target feature of MapInfo Professional's Edit
menu. Before you choose Combine, you can select one map object, and designate that object as the
editing target. You can then select additional map objects and choose Combine to combine the selected
objects with the target. If you set a target before you choose Combine, the Combine operation is more
flexible, allowing you to combine objects from different tables.
You should assign a target object if one of the objects you are combining is more important than any of
the other objects. For example, if you want to add small, unnamed islands to an existing "mainland"
region, you should make the mainland region the target object. If you designate the mainland region as
the target, MapInfo Professional is able to retain the mainland region's name after the objects are
combined.
Using Combine with Set Target allows the mainland region to retain its name after the objects are
combined. You can only set one object as the target at a time when using Combine with Set Target. The
modifying object can consist of more than one object.
Keep in mind that the Objects Combine command works with selected map objects. To apply the combine
operation to an entire table, use Select All in the Query menu. To combine into groups rather than objects,
or output to a separate table, use Combine Objects Using Column in the Table menu.
To combine map objects using Set Target:
1. Select one object in an editable layer to be the target object.
2. On the Objects menu, click Set Target. The object displays in a different style to indicate that it is
the target object.
MapInfo Professional 12.5 298
Editing Objects using the Set Target Model