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<DIV><SPAN class=789123814-04052009><FONT face=Arial color=#0000ff size=2>Ah
yes, a classic case of RTFM. </FONT></SPAN></DIV>
<DIV><SPAN class=789123814-04052009><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=789123814-04052009><FONT face=Arial color=#0000ff size=2>Is
this acceptable behavior for this function? Could PostGIS deal with this
internally to do a post process st_pointonsurface when the centroid is not
within the polygon.</FONT></SPAN></DIV>
<DIV><SPAN class=789123814-04052009><FONT face=Arial color=#0000ff
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=789123814-04052009><FONT face=Arial color=#0000ff size=2>For
now I guess I will just write a wrapper function for ( CASE WHEN
st_within(st_centroid(), poly) then st_centroid() else st_pointonsurface() END
)</FONT></SPAN></DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px solid; MARGIN-RIGHT: 0px">
<DIV></DIV>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left><FONT
face=Tahoma size=2>-----Original Message-----<BR><B>From:</B>
postgis-users-bounces@postgis.refractions.net
[mailto:postgis-users-bounces@postgis.refractions.net] <B>On Behalf Of
</B>Paragon Corporation<BR><B>Sent:</B> Friday, May 01, 2009 3:22
PM<BR><B>To:</B> 'PostGIS Users Discussion'<BR><B>Subject:</B> RE:
[postgis-users] st_centroid Points not on Polygon<BR><BR></FONT></DIV>
<DIV dir=ltr align=left><SPAN class=156482122-01052009><FONT face=Arial
color=#0000ff size=2>Stan,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=156482122-01052009><FONT face=Arial
color=#0000ff size=2>ah and here is proof.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=156482122-01052009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=156482122-01052009><FONT face=Arial
color=#0000ff size=2><A
href="http://postgis.refractions.net/documentation/manual-svn/ST_Centroid.html">http://postgis.refractions.net/documentation/manual-svn/ST_Centroid.html</A></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=156482122-01052009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=156482122-01052009><FONT face=Arial
color=#0000ff size=2>Leo</FONT></SPAN></DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<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></BLOCKQUOTE></BODY></HTML>