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Dear list,<br>
<br>
The following query:<br>
<br>
<span>SELECT ST_intersection(<wbr>st_geometryfromtext(<wbr>('MULTIPOLYGON((<wbr>(-3.577895<wbr>
53.954289,0.816178 54.779474,2.624587 51.01611,0.702327
50.669834,-1.425339 50.243136,-1.424992 50.243209,-3.577895
53.954289)))'),4326)<wbr>::geography,st_geome<wbr>tryfromtext(('POLYGON(<wbr>(-0.38928<wbr>
51.5446,-0.1703 51.5446,-0.1703 51.389328,-0.38928
51.389328,-0.38928 51.5446))'),4326)<wbr>::geography);<br>
</span><br>
fails with the following error:<br>
"ERROR: Error performing intersection: TopologyException: Input
geom 0 is invalid: Self-intersection at or near point
1482705.9601906976 781580.61046449794 at 1482705.9601906976
781580.61046449794"<br>
<span><br>
If I remove "::geography" from both geometry's, it works. It also
works if I add a small buffer to the first geometry. Postgis
reports that both geometry's are valid.<br>
<br>
I'm running:<br>
</span><br>
<span>PostgreSQL 9.4.1 on x86_64-unknown-linux-gnu, compiled by gcc
(GCC) 4.8.2 20140120 (Red Hat 4.8.2-16), 64-bit POSTGIS="2.1.5
r13152" GEOS<br>
="3.4.2-CAPI-1.8.2 r3921" PROJ="Rel. 4.8.0, 6 March 2012"
GDAL="GDAL 1.11.2, released 2015/02/10" LIBXML="2.9.1"
LIBJSON="UNKNOWN" TOPOLOG<br>
Y RASTER<br>
<br>
Any help appreciated.<br>
<br>
Regards,<br>
Graham<br>
</span>
<pre class="moz-signature" cols="72">--
Graham Glanfield
Geocento Ltd
Electron Building
Fermi Avenue
Harwell
Didcot
Oxfordshire
OX11 0QR</pre>
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