CIRCLE Command:

The CIRCLE command allows you to create circles that originate from a single center point, that pass through 2 points, that pass through 3 points, or that are tangent to two elements.

click on the Circle button,

OR

type c or circle at a Command: prompt,

OR

select Circle under the Draw Menu.

Center Point and Radius or Diameter

Activate the CIRCLE command.
--Prompt: 3P/2P/TTR/<Center point>: Press ENTER to accept the default selection of < Center point >
Locate the circle's center by using an Osnap (Object Snap),
an Absolute Coordinate, a Relative Rectangular Coordinate, or Relative Polar Coordinate.

--Prompt: Diameter /<Radius>:
NOTE: Radius is AutoCAD's default selection, but diameter is also an option at this prompt. To enter a numeric value for the radius at this prompt, type in the number and press Enter. To enter a diameter value, type d for diameter, press Enter, and type in the numeric value for the diameter at the next prompt.

A circle should appear.

Tangent, Tangent, Radius

Activate the CIRCLE command (see methods above)

--Prompt: 3P/2P/TTR/<Center point>:
Type ttr and then press the Enter key to accept the tangent, tangent, radius option.

--Prompt: Enter Tangent spec: Use the LEFT mouse button to click on the first tangent element, approximately where the circle will touch.

--Prompt: Enter second Tangent spec: Use the mouse to click on the second tangent element, approximately where the circle will touch.


--Prompt: Radius: Type in a radius value,

OR

type d for diameter and then press the Enter key.

If you are using a diameter, AutoCAD now asks for a diameter value. Type in the number and press Enter.

---A circle should appear.

3 Points

Activate the CIRCLE command (see methods above)
--Prompt: 3P/2P/TTR/<Center point>: Type 3p and then press the Enter key to accept the the three point selection.

---Prompt: One at a time, a prompt asks you to select the elements the circle should touch.
Use an Absolute Coordinate, Relative Rectangular Coordinate, Relative Polar Coordinate, or Osnap to locate the points through which the circle will pass.

2 Points

Activate the CIRCLE command (see methods above)

--Prompt: 3P/2P/TTR/ <Center point>: Type 2p and then press the Enter key to accept the 2p selection.

--Prompt: One at a time, a prompt asks you to select the elements the circle should touch.
Use an Absolute Coordinate, Relative Rectangular Coordinate, Relative Polar Coordinate, or Osnap to locate the points through which the circle will pass.