Tandy 1000 Basic Reference Manual page 116

Chapter 10 I BASIC
Keywords
CIRCLE/Graphics Statement
Draws an ellipse on the screen with the specified center and
radius.
(x,y)
specify the coordinate for the center of the circle. x is the
horizontal coordinate and y is the vertical coordinate.
Color
indicates the color of the ellipse and must be a valid num-
ber in the current color set.
The STEP option tells BASIC that the (x,y) coordinates are rela-
tive to the last point referenced.
The possible ranges for
x,
y, and
color
depend upon the current
screen mode as defined in Chapter 8, "Displaying Color and
Graphics.
"
Radius is
the major axis of the ellipse.
Start
and end are the beginning and ending angles in radians
and must be in the range -6.283186 to 6.283186, or -2
*
PI to
2
*
PI, where PI equals 3.141593. If you specify a negative
start
or end angle, the ellipse is connected to the center point with a
line, and the angles are treated as if they were positive.
Aspect
is the ratio of the x-radius to the y-radius in terms of co-
ordinates. If
aspect
is less than 1,
radius
is the x-radius and is
measured i n points in the horizontal direction. If
aspect
is
greater than 1,
radius
is the y-radius and is measured in points
in the vertical direction. If you omit
aspect,
BASIC uses the de-
faults for the current screen mode as defined in Chapter 8. When
you use the default, BASIC draws a circle.
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