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<DIV dir=ltr align=left><SPAN class=998184401-27102009><FONT color=#0000ff
size=2 face=Arial>Mehmet,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=998184401-27102009><FONT color=#0000ff
size=2 face=Arial>It sounds like your line string might have 0 or 1
points.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=998184401-27102009><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=998184401-27102009><FONT color=#0000ff
size=2 face=Arial>Use</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=998184401-27102009><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=998184401-27102009><FONT color=#0000ff
size=2 face=Arial>ST_NPoints(linestring) < 2 to find all linestrings
with fewer than 2 points</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=998184401-27102009><FONT color=#0000ff
size=2 face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=998184401-27102009><FONT color=#0000ff
size=2 face=Arial>Leo</FONT></SPAN></DIV><BR>
<DIV dir=ltr lang=en-us class=OutlookMessageHeader align=left>
<HR tabIndex=-1>
<FONT size=2 face=Tahoma><B>From:</B>
postgis-users-bounces@postgis.refractions.net
[mailto:postgis-users-bounces@postgis.refractions.net] <B>On Behalf Of
</B>Mehmet Sirin<BR><B>Sent:</B> Monday, October 26, 2009 7:24 PM<BR><B>To:</B>
PostGIS Users Discussion<BR><B>Subject:</B> [postgis-users] ST_UNION - Exception
in LWGEOM2GEOS<BR></FONT><BR></DIV>
<DIV></DIV>
<DIV>Hi,<BR></DIV>
<DIV></DIV>
<DIV>I just tried to create a mutlilinestring out of a set of linestrings
via </DIV>
<DIV></DIV>
<DIV>SELECT AsText( ST_UNION(linestring) )<BR><BR>FROM ways w, way_tags wt WHERE
<A href="http://w.id">w.id</A>=wt.way_id <BR>AND wt.v='Dörnter
Weg'<BR><BR></DIV>
<DIV>(it lies in Osnabrück, lower saxony)</DIV>
<DIV></DIV>
<DIV>but I'm getting this strange error: </DIV>
<DIV></DIV>
<DIV>HINWEIS: IllegalArgumentException: point array must contain 0 or >1
elements<BR><BR><BR>FEHLER: Exception in LWGEOM2GEOS<BR><BR>********** Fehler
**********<BR><BR>FEHLER: Exception in LWGEOM2GEOS<BR>SQL
Status:XX000<BR><BR><BR></DIV>
<DIV>Replacing wt.v='Dörnter Weg' with wt.v='Some other Streets' it
works properly. </DIV>
<DIV>So it is because of this street 'Dörnter Weg' (i got a few other ones of
this kind in my database). </DIV>
<DIV>Anybody can tell me why these sort of ways leads to a problem?</DIV>
<DIV></DIV>
<DIV></DIV>
<DIV>thank you</DIV>
<DIV>kind regards</DIV>
<DIV>mehmet sirin</DIV></BODY></HTML>