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<DIV><SPAN class=351283821-05112004><FONT face=Arial size=2>A bug was recently
reported involving isValid throwing an exception for polygons with certain kinds
of invalid hole rings. This has now been fixed and will appear in the next
release of JTS (and probably GEOS too).</FONT></SPAN></DIV>
<DIV><SPAN class=351283821-05112004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=351283821-05112004><FONT face=Arial size=2>(The problem test
case is:</FONT></SPAN></DIV>
<DIV><SPAN class=351283821-05112004><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=351283821-05112004><FONT face=Arial size=2>POLYGON
((<BR> 37.654639 55.726496,
<BR> 37.654056 55.726947,
<BR> 37.653801 55.727333,
<BR> 37.653801 55.727435,
<BR> 37.654468 55.727483,
<BR> 37.656654 55.727466,
<BR> 37.656572 55.727063,
<BR> 37.656654 55.726713,
<BR> 37.657052 55.726531,
<BR> 37.657571 55.726365,
<BR> 37.658071 55.725961,
<BR> 37.658321 55.725609,
<BR> 37.658303 55.725374,
<BR> 37.658321 55.725609,
<BR> 37.658906 55.725309,
<BR> 37.659488 55.72511,
<BR> 37.658135 55.724571,
<BR> 37.657386 55.724922,
<BR> 37.657135 55.724873,
<BR> 37.65647 55.725274,
<BR> 37.655635 55.725828,
<BR> 37.655195 55.7265,
<BR> 37.655635 55.725927,
<BR> 37.654639
55.726496<BR> ),
(<BR> 37.658321 55.725609,
<BR> 37.658906 55.725309,
<BR> 37.659488 55.72511,
<BR> 37.658906 55.725309,
<BR> 37.658321
55.725609<BR> ))</FONT></SPAN></DIV>
<DIV> </DIV>
<DIV align=center><FONT face=Arial size=2><STRONG>Martin Davis, Senior Technical
Architect</STRONG><BR><STRONG><FONT color=#0000ff>Vivid Solutions
Inc.
<I>www.vividsolutions.com</I></FONT></STRONG><BR></FONT><EM><FONT face=Arial
size=2>Suite #1A-2328 Government Street Victoria, B.C. V8T 5G5<BR>Phone: (250)
385 6040 - Local 308 Fax: (250) 385 6046</FONT></EM></DIV>
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