Summary
Instructions provided show how to add an area field to a polygon theme attribute table by creating an empty number field and then populating the field using the Field Calculator.
Procedure
- Create a new number field in the attribute table of the polygon theme.
- Open the table and select Start Editing from the Table menu.
- Select Add Field from the Edit menu.
- In the Field Definition dialog box:
- Set Name to an appropriate name, for example 'Area'.
- Set Type to Number.
- Set Width to an appropriate number, for example '32'.
- Set Decimal Places to the desired number, for example '6'.
- Click OK.
- Select Stop Editing from the Table menu and save the edits.
- Populate the new field with area values.
Note:
ArcView calculates the area in the same units used to store the polygons in the shapefile.
Note:
To calculate the perimeter use the following expression:
Code:
[Shape].ReturnLength
- Open the table and Start Editing if necessary.
- Make the area field active.
- Select Calculate from the Field menu.
- Double-click Shape from the Fields category.
- Type .ReturnArea in the expression box after [Shape].
The final expression should look similar to this:
Code:
[Shape].ReturnArea
- Click OK.
- Select Stop Editing from the Table menu and save the edits.