Draws ellipses and elliptical arcs.
Accessing the Command
command bar: ellipse
alias: el
menu bar: Draw  Ellipse
Draw  Elliptical Arc
ribbon: Draw  Draw  Ellipses
toolbar: Draw 
Draw 
: Ellipse
Prompts you in the command bar:
First end of ellipse axis or [Arc/Center]: (Pick a point, or else enter an option)
Second end of axis: (Pick another point)
Set Other axis or [Rotation]: (Pick a third point, or enter R)
All methods to draw ellipses can be found in the Draw  Ellipse menu:
All methods to draw elliptical arcs can be found in the Draw  Elliptical Arc menu:
Command Options
Option 
Description 
First End of Ellipse Axis 
Specifies the first endpoint of the first axis. Ellipses are defined by the length of two axes, or one axis and an angle of rotation. 
Second End of Axis 
Specifies the other end of the first axis. 
Other Axis 
Specifies the endpoint of the second axis, measured from the center of the first axis. The longer of the two axes is called the "major axis"; the shorter one is called the "minor axis." 
Arc 
Draws elliptical arcs; prompts you:

Parameter 
Specifies parameters for the parametric formula that crafts the elliptical arc: p(b) = c + a * cos(u ) = b * sin(u ) where: a = major axis. b = minor axis. c = center of the ellipse. u = point along the arc. Cos and Sin are the trigonometric cosine and sine functions. 
Start Angle of Arc 
Specifies the start angle, creating the arc's starting point. The angles are measured counterclockwise from the positive x axis. 
End Angle 
Specifies the end angle, creating the arc's endpoint. 
Included 
Specifies the included angle, measured from the starting point. 
Center 
Draws the ellipse starting with a center point; prompts you: Center of ellipse  (pick a point, or enter x, y coordinates.) 
Endpoint of Axis 
Specifies the endpoint of one axis, measured from the center point. 
Other Axis 
Specifies the endpoint of the other axis, also measured from the center point. 
Rotation 
Specifies the angle of the ellipse; prompts you: Rotation around major axis  (pick a point, or enter an angle between 0 and 89.9 degrees. An angle of 0 degrees draws a circle; 89.9 draws a very thin ellipse.) 
Procedures
 Setting the Polyline Ellipse (PELLIPSE) variable
 General procedure to draw an elliptical arc
 Editing an ellipse
 Editing an elliptical arc
Grips Editing
Ellipses can be edited directly through grips:

Select the ellipse. Notice that it has five grips.

Drag the grips to perform the following actions:
 Drag a quadrant grip to stretch the ellipse (increase or decrease the diameter).
 Drag the center point grip to move the ellipse.
Related Commands
Arc  draws circular arcs.
Isoplane  change the working isoplane for drawing isometric entities, including isocircles, which are made from ellipses
Properties  changes the properties of ellipses through a palette.