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<DIV dir=ltr align=left><SPAN class=484421822-01052009><FONT face=Arial
color=#0000ff size=2>Stan,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=484421822-01052009><FONT face=Arial
color=#0000ff size=2>I think the answer is no. For example if you have a
polygon with holes, the centroid may very well lie in the
hole.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=484421822-01052009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=484421822-01052009><FONT face=Arial
color=#0000ff size=2>Leo</FONT></SPAN></DIV><BR>
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<FONT face=Tahoma size=2><B>From:</B>
postgis-users-bounces@postgis.refractions.net
[mailto:postgis-users-bounces@postgis.refractions.net] <B>On Behalf Of
</B>Sufficool, Stanley<BR><B>Sent:</B> Friday, May 01, 2009 4:53
PM<BR><B>To:</B> PostGIS Users Discussion<BR><B>Subject:</B> [postgis-users]
st_centroid Points not on Polygon<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV><SPAN class=331285020-01052009><FONT face=Arial size=2>I'm sure I ran
across this in the forums a year ago, but:</FONT></SPAN></DIV>
<DIV><SPAN class=331285020-01052009><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=331285020-01052009><FONT face=Arial size=2>Is the st_centroid
function guaranteed to return a point that lies on the polygon? I have instances
when my display doe not place it on the polygon when using
st_centroid(st_intersection(the_geom, <WKT BBOX>));</FONT></SPAN></DIV>
<DIV><SPAN class=331285020-01052009></SPAN><SPAN class=331285020-01052009><FONT
face=Arial size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=331285020-01052009><FONT face=Arial size=2>Thanks in
advance.</FONT></SPAN></DIV></BODY></HTML>