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Bug in Graphics output of Circle primitive?

• To: mathgroup at smc.vnet.net
• Subject: [mg62860] Bug in Graphics output of Circle primitive?
• From: Yves Klett <yk at despammed.com>
• Date: Tue, 6 Dec 2005 23:10:53 -0500 (EST)
• Organization: Comp.Center (RUS), U of Stuttgart, FRG
• Sender: owner-wri-mathgroup at wolfram.com

Dear Mathgroup,

I stumbled upon a strange (and suspicious) graphics output when 
displaying arcs with small angular length.

If I evaluate the following lines:

r = 10000;
gx = Circle[{r, 0}, r, {179°, 180°}];
Show[Graphics[{gx, Point[{0, 0}]}], Axes -> True,
  PlotRange -> {Automatic, Automatic}, AxesOrigin -> {0, 0}];

(or the same in plain text format...)

r=10000;
gx=Circle[{r,0},r,{179\[Degree],180\[Degree]}];
Show[Graphics[{gx,Point[{0,0}]}],Axes\[Rule]True,
     PlotRange\[Rule]{Automatic,Automatic},AxesOrigin\[Rule]{0,0}];


I get the point as specified at the origin {0,0}. The arc though does 
not intersect at the origin as it should IMHO, but somewhat left of it. 
  Same thing occurs for arbitrary values of r.

There might be some precision problem of the postscript output 
concerning the Circle primitive when very different axes scaling is 
used, but any enlightment would be appreciated.

I am using V5.2 on windows. Any hints or tips to get rid of this faulty 
output would be very welcome,

Yves Klett

• Follow-Ups:
  • Re: Bug in Graphics output of Circle primitive?
    • From: pantagruel123@aol.com
  • Re: Bug in Graphics output of Circle primitive?
    • From: Zhengji Li <zhengji.li@Gmail.com>