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<p class=MsoNormal><span lang=EN-US>Hi <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I’m a newbie to PostGIS and I have
same problem with function distance(geometry, geometry). I need to know the
distance between two points IN METERS but distance return a number that represent
the distance into carthesian system but I don’t know how convert this
number in meters… Or there is another war to do this!?!<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>PS.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>I use geoserver to show maps and works very
well…<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>This is a my example query:<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>select <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>distance(<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US> geomfromtext('POINT(14.7926950454712
41.1229515075684)', 4236), <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US> geomfromtext('POINT(14.7931413650513
41.1228904724121)', 4236) <o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US> );<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Return 0,000450473592882729 !?!!?<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Since SRID 4236 has UNIT["degree",…]
I tried to use the “transform” function in this way:<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>select distance(<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US> transform(PointFromText('POINT(14.7926950454712
41.1229515075684)', 4236), 26986),<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>
transform(PointFromText('POINT(14.7931413650513 41.1228904724121)', 4236),
26986)<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US>
);<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Because SRID 26986 has UNIT["metre"…]<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>But I didn’t solve the problem.<o:p></o:p></span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>Thanks Fabio<o:p></o:p></span></p>
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