Ellipse

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:

Center - specify the center point of the elliptical arc.

First end of ellipse axis - specify the endpoint of the elliptical arc's first axis.

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 counter-clockwise 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.