HP 5961-0509 manual 20-10The Vector Group

Note	Do not use an adaptive line type when drawing arcs with small chord
	angles. The printer attempts to draw the complete pattern in every
	chord (there are 72 chords in a circle using the default chord angle).
	z XCenter, YCenter — Specify the absolute location of the center
		of the arc. (The center of the arc is the center of the circle that
		would be drawn if the arc was 360 degrees.)
	z Coordinates are interpreted in current units: as user-units when
		scaling is on; as plotter units when scaling is off. If current scaling
		is not isotropic, the arc drawn is elliptical rather than circular.
	z Sweep Angle — Specifies in degrees the angle through which
		the arc is drawn. A positive angle is drawn in a positive direction
		(angle of rotation); a negative angle is drawn in the negative
		direction.
	z Chord Angle — Specifies the chord angle used to draw the arc.
		The default is a chord angle of 5 degrees. The chord angle
		specifies, in degrees, the maximum angle created when lines
		from each end of the chord intersect the center point of the circle
		(see drawing below). The smaller the chord angle, the smoother
		the curve.

Figure 20-7 Chord Angle

20-10The Vector Group EN