Autodesk 057B1-41A111-1001 - AutoCAD LT 2010, Руководство пользователя

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Use Commands to Calculate Area
With the MEASUREGEOM and AREA commands, you can specify a series of
points or select an object to calculate area. If you need to calculate the
combined area of multiple objects, you can keep a running total as you add
or subtract one area at a time from the selection set. You cannot use window
selection or crossing selection to select objects.
Total area and perimeter are saved in the AREA and PERIMETER system
variables.
In addition to area, with the MEASUREGEOM command, you can obtain
geometric information from objects such as distance, radius, angle, and volume.
Define an Area
You can measure an arbitrary closed region defined by the points you specify.
The points must lie on a plane parallel to the XY plane of the current UCS.
Calculate the Area, Perimeter, or Circumference of an Object
You can calculate the enclosed area and perimeter or circumference of circles,
ellipses, polylines, polygons, regions, and AutoCAD 3D solids. The information
displayed depends on the type of object selected:
■ Circles. Area and circumference display.
■ Ellipses, closed polylines, polygons, planar closed spline curves,
and regions. Area and perimeter display. For wide polylines, this area is
defined by the center of the width.
■ Open objects such as open spline curves and open polylines. Area
and length display. Area is calculated as though a straight line connects
the start point and endpoint.
■ AutoCAD 3D solids. Total 3D area for the object displays.
Use Precision Tools | 167