ANGLE allows you to to determine the direction of a 
tangent vector by setting the angle between the tangent 
vector and the positive x axis.

Enter an angular value (in degrees) and press <Enter>. The
rotation angle that you specify is relative to the
construction view z axis. A positive angle indicates a
counter-clockwise rotation about the construction view z
axis, when that axis is pointing toward you.

Select a reference line near the desired endpoint, from
which the new line is to be created.

With the line limits switch set to FUNCTN, the new line is
the same length as the reference line. With the line 
limits switch is set to VIEWPORT, the new line extends 
to the limits of the screen display.

In 2-D construction mode, the reference line is projected 
to the current construction plane, and the new line is 
created in the current construction plane.

In 3-D construction mode, the system locates a plane that 
is parallel to the current construction plane and that
passes through the designated endpoint of the reference
line. The reference line is projected to this plane and 
the new line is created in this plane.
