At 02:52 PM 11/5/98 -0800, you wrote:
>One link that explains quite well is:
>
>http://www.am.qub.ac.uk/world/lists/pic/msg00334.html
>
>Yes, this was discussed on the pic list 3 years ago. And (as usual) Andy
>gave a clear explanation.

Hi Scott,

I just went to that link and directly converted Andy's pseudocode into
BASIC code and it produces a diamond for me, not a circle. I tried various
radius settings, yet the figure definately has straight sides. Maybe I'm
doing something wrong? This algorythm just fascinates me because I don't
understand how it works and I don't have time at the moment to figure it
out (have to run to a meeting).

Thanks, Sean

P.S. The BASIC code is given below:

SCREEN 12
WINDOW SCREEN (-100, 100)-(100, -100)
radius = 50
x = 0
y = radius
switch = 3 - 2 * radius
LOP:
PSET (x, y): PSET (x, -y): PSET (-x, y): PSET (-x, -y)
PSET (y, x): PSET (y, -x): PSET (-y, x): PSET (-y, -x)
IF switch < 0 THEN switch = switch + 4 * x + 6 ELSE switch = switch + 4 *
(x - y) + 10
y = y - 1
x = x + 1
IF x <= y THEN GOTO LOP






>
>Scott
>
+-------------------------------+
| Sean Breheny                  |
| Amateur Radio Callsign: KA3YXM|
| Electrical Engineering Student|
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