Datasheet

Understanding How Command Options Work  25
Understanding How Command Options Work
Nearly every AutoCAD command offers a set of options shown at the command-line
prompt. These options let you alter the behavior of a command to suit your current
drawing. To see how command options work, and to get a feel for the drawing process
in general, in this exercise you’ll draw an arc and then place it exactly in the inside corner
of the rectangle:
1. Click the Arc tool in the Draw panel.
The prompt
Specify start point of arc or [Center]: appears,
and the cursor changes to a crosshair cursor.
2. If you examine this Specify start point of arc or [Center]: prompt, you’ll see that
the start point contains two options. The default option is stated in the main part
of the prompt: Specify start point. If other options are available, they appear within
brackets, as in the [Center] option that appears in the Arc tool’s command prompt.
This [Center] option tells you that you can also start your arc by selecting a center
point instead of a start point. If multiple options are available, they appear within the
brackets and are separated by slashes (/). The default is the option AutoCAD assumes
you intend to use unless you tell it otherwise.
3. Enter C↵ to select the Center option. The prompt Specify center point of arc:
appears. Notice that you had to enter only the C and not the entire word Center.
When you see a set of options in the command line, note their capitalization. If
you choose to respond to prompts by using the keyboard, these capitalized letters
are all you need to enter to select that option. In some cases, the first two letters are
capitalized to differentiate two options that begin with the same letter, such as LAyer
and LType.
4. Now select a point for the center of the arc, as shown in Figure 1.20. The prompt
Specify start point of arc: appears. You’ll also see a rubber-banding line from the
center point you just selected to your cursor.
Finally click here for
the end point.
First click here for
the arc center.
Then click here for
the start point.
Figure 1.20
Using the Arc
command
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