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<DIV dir=ltr align=left><SPAN class=109122601-10122009><FONT color=#0000ff
face=Arial>Satish,</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=109122601-10122009><FONT color=#0000ff
face=Arial>AsText and AsEWKT only show the first 15 or 16 digits so I suspect
your real geometries have more digits and are really off by a small
amount.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=109122601-10122009><FONT color=#0000ff
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=109122601-10122009><FONT color=#0000ff
face=Arial>To be sure use the ST_AsHexEWKB representation of the ST_AsEWKT
instead of and you will see the distance is probably > 0
but very small.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=109122601-10122009><FONT color=#0000ff
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=109122601-10122009><FONT color=#0000ff
face=Arial></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=109122601-10122009><FONT color=#0000ff
face=Arial>Leo</FONT> </SPAN></DIV><BR>
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<FONT face=Tahoma><B>From:</B> postgis-users-bounces@postgis.refractions.net
[mailto:postgis-users-bounces@postgis.refractions.net] <B>On Behalf Of
</B>Satish Murthy<BR><B>Sent:</B> Wednesday, December 09, 2009 11:28
AM<BR><B>To:</B> postgis-users@postgis.refractions.net<BR><B>Subject:</B>
[postgis-users] ST_INTERSECT returns false, but should return
true<BR></FONT><BR></DIV>
<DIV></DIV><PRE>Hi,<BR><BR>I can't figure out why this is happening:<BR><BR>This works, returning true:<BR>SELECT Intersects(<BR>GeomFromEWKT('MULTILINESTRING((-26.9599999999939 -29.97 1 0,-26.9399999999976 -29.99 2 0),(-25.8599999999937 -29.97 1 0,-26.9399999999976 -29.99 2 0))'), <BR> GeomFromEWKT('POINT(-26.9599999999939 -29.97 1 0)')) ;<BR><BR>If I select the same as geometries, it returns false<BR>SELECT ST_Intersects(<BR> <BR>(select geom1 from tab), <BR><BR> (select geom2 from tab)) ;<BR><BR><BR>Weird thing is, <BR> select ST_DISTANCE (geom1, geom2)<BR>returns 3.51700710773038e-14<BR><BR>This behavior is not consistent - sometimes ST_INTERSECTS returns true correctly.<BR><BR>Can anyone suggest what might be the problem here?<BR><BR>Thanks,<BR>Satish<BR></PRE><BR>
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