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<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2>Nicklas,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2>You are correct there is no function for doing this.
We have on occasion needed to do this ourselves and what we usually do is
</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2>1) first find the minimum distance </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2>2) figure out which point/pointset on the geometry
satisfies the minimum distance using buffer and intersection (with minimum
distance being the buffer distance).</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2>I think I have the code lying around here
somewhere.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2>As far as ST_Distance goes. Haven't looked at the
code that closely, but it does some sort of recursive call and there could be
more than one point that satisfies the condition and it only cares about the
first one it comes across so such a thing may or may not be quite what you are
looking for.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2>Hope that helps,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2>Regina</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=443051916-11022009><FONT face=Arial
color=#0000ff size=2></FONT></SPAN> </DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
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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>nicklas.aven@jordogskog.no<BR><B>Sent:</B> Wednesday, February 11, 2009 4:47
AM<BR><B>To:</B> postgis-users@postgis.refractions.net<BR><B>Subject:</B>
[postgis-users] points from st_distance<BR></FONT><BR></DIV>
<DIV></DIV>
<P>Hallo</P>
<P>I have a question or suggestion.</P>
<P>If I have missed some functionality please tell me. </P>
<P>The thing is I have often needed information about from which points the
distance in st_distance is calculated.<BR>I mean, somewhere in the function the
information have to be. Would it be possible to build a new function which
<BR>returned the distance, startpoint, endpoint as array or something like
that.</P>
<P>Am I right about that this functionality is missing and<BR>am I right about
that the points have to be identified somewhere in the function and that it
ought to be possible to present them in a function.</P>
<P>If I'm right so far I would like to come this as a suggestion.</P>
<P>I also have to thank you all for postgis. <BR>It has been a very nice
experience to start handling the gis analysing and processing in
database-environment.<BR>My next step is to try to manage any of the procedural
languages. Then I guess I can do just anything with all the points and polygons
out there :-).</P>
<P>/Nicklas</P></BODY></HTML>