Constructing Ellipses and Elliptical Arcs

An Ellipse has a center like a Circle, but has a longer radius along its major axis and a shorter radius along its minor axis. You can construct Ellipses or elliptical Arcs of any size.

To construct Ellipses from a center point and the radii of perpendicular axes:

1. Click Draw > Ellipse > Center (or type Ellipse, then specify the Center option).
2. In the graphics area, specify:
   1. Center of the ellipse's axes.
   2. Axis end point.
   3. Radius of the perpendicular axis.

      - or -

      Specify the Rotation option to create the Ellipse via the angle that is defined by the ratio of the major to minor axis. You can specify an angle between 0 and 89.9°. The larger the angle, the flatter the Ellipse.

To construct Ellipses from an axis defined by its end points and the radius of the perpendicular axis:

1. Click Draw > Ellipse > Axis, End (or type Ellipse).
2. In the graphics area, specify:
   1. Axis start point.
   2. Axis end point.
   3. Radius of the perpendicular axis.

To construct elliptical Arcs:

1. Click Draw > Ellipse > Arc (or type Ellipse, then specify the Elliptical arc option).
2. In the graphics area, specify:
   1. Axis start point.
   2. Axis end point.
   3. Radius of the perpendicular axis.
   4. End point of the Arc, or type the angle between a Ray from the Ellipse center to its intersection with the Ellipse.
   5. Angle defining the Ray from the Ellipse center axis intersecting the Ellipse at the other end point of the Arc, or specify an option:
      • Parametric vectors: Specifies the Arc by the factor that defines its portion of the entire Ellipse area.
      • Total angle: Specifies the other arc end point on the Ellipse from a Ray defined by an included angle defined by the Ellipse axes.

Access

Command: Ellipse

Menu: Draw > Ellipse