void uradlin (xpos, ypos, rad1, rad2, theta) CIRCLES.C Level 3
float xpos, ypos Coordinates of the center of the circle in user units .
float rad1, rad2 The line is drawn from rad1 to rad2 in user units..
float theta The line is drawn at the angle theta in radians.
uradlin() is used to draw a piece of a radial line in a circle in user units. The two radii are in the units of the x axis.