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Product: MapInfo
Version: 5.x/6.x
Platform: Not Platform Related
Category: Formulas\Calculations
Summary:
Changing area units.
Question:
How can the area units used by MapBasic functions in SQL Select
statements like Area() be changed? How can the area units that are used in
the map window be changed?
Answer:
The area units used by MapBasic functions in SQL Select
statements, like Area(), can be changed by using the following command in the
MapBasic window:
Set Area Units Statement
Purpose
Sets MapBasic's default area unit.
Syntax
Set Area Units area_name
area_name is a string representing the name of
an area unit (e.g. "acre")
Description
The Set Area Units statement sets MapInfo's default area unit of
measure. This dictates the area unit used within MapInfo's SQL Select dialog.
By default, MapBasic uses square miles as an area unit; this unit remains in
effect unless a Set Area Units statement is issued.
The area_name parameter must be one of the String values listed
in the table below:
The area units that are used in the Map Window can be changed by
using the following command in the MapBasic window:
Set Map Area Units Statement
Purpose
Modifies an existing Map Window's area units.
Syntax
Set Map Area Units area_name
area_name is a string representing the name of
an area unit (e.g. "acre")
Description
The Set Map Area Units statement specifies the unit of measure
used to display area calculations for the current map window.
The area_name parameter must be one of the String values listed
in the table below:
Area_Name Parameters
Unit name Unit represented
"acre" acres
"hectare" hectares
"perch" perches
"rood" roods
"sq ch" square chains
"sq cm" square centimeters
"sq ft" square feet
"sq in" square inches
"sq km" square kilometers
"sq li" square links
"sq m" square meters
"sq mi" square miles
"sq mm" square millimeters
"sq rd" square rods
"sq survey ft" square survey feet
"sq yd" square yards
The Map Window area units can also be changed by going to
Map>Options and changing the value in the Area Units drop down. Changing
this does not change the area units used by SQL Select.
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