Datasheet

Understanding How Command Options Work  31
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 1.13. 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.
If you point directly to the right, you’ll see that the rubber-banding line snaps to
an exact horizontal orientation, and you’ll see a tooltip appear at the cursor. This
is a feature called polar tracking vector, and it helps you draw in exact horizontal
Figure 1.13
Using the Arc
command
Finally click here for
the end point
First click here for
the arc center
Then click here for
the start point
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