2004

Table Of Contents
512 | Chapter 20 Dimensions and Tolerances
Associative Dimensions
Dimension associativity defines the relationship between geometric objects
and the dimensions that give their distance and angles. AutoCAD provides
three types of associativity between geometric objects and dimensions.
Associative dimensions. Automatically adjust their locations, orienta-
tions, and measurement values when the geometric objects associated
with them are modified. Dimensions in a layout may be associated to
objects in model space. The
DIMASSOC system variable is set to 2.
Nonassociative dimensions. Selected and modified with the geometry
they measure. Nonassociative dimensions do not change when the geo-
metric objects they measure are modified. The dimension variable
DIMASSOC is set to 1.
Exploded dimensions. Contain a collection of separate objects rather
than a single dimension object. The
DIMASSOC system variable is set to 0.
You can determine whether a dimension is associative or nonassociative by
doing one of the following:
Select the dimension and use the Properties palette to display the proper-
ties of the dimension.
Use the LIST command to display the properties of the dimension.
You can also use the Quick Select dialog box to filter the selection of associa-
tive or nonassociative dimensions. A dimension is considered associative
even if only one end of the dimension is associated with a geometric object.
The
DIMREASSOCIATE command displays the associative and nonassociative
elements of a dimension.
Special Situations and Limitations
You may need to use
DIMREGEN to update associative dimensions after
panning or zooming with a wheel mouse, after opening a drawing that was
modified with an earlier release, or after opening a drawing with external
references that have been modified.
Although associative dimensions support most object types that you would
expect to dimension, they do not support multiline objects or objects with
nonzero thickness.
When selecting objects to dimension, make sure that the objects that you
select don’t include a directly overlapping object that does not support
associative dimensioning. An example of the latter would be a 2D solid.
Associativity is not maintained between a dimension and a block reference if
the block is redefined.