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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>Just remembered <<#>> is for ND boxes, and we did take it out, recalling a convo pramsey had a long time ago.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>But I think the comment still remains the same<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This one - <a href="https://postgis.net/docs/manual-dev/en/geometry_distance_centroid_nd.html">https://postgis.net/docs/manual-dev/en/geometry_distance_centroid_nd.html</a> used to just do centroid of the boxes and the other one was for distance of the boxes.<o:p></o:p></p><p class=MsoNormal>When we changed to true KNN, distance would always be better so we scrapped all the box distance variants and the centroid ones then all became true distance. I think the comment about <<->> is now wrong and it should be true distance<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>e.g<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>SELECT ST_GeomFromText('MULTIPOINT(1 3 2, 0 0 0)') <<->> ST_GeomFromText('LINESTRING(1 1 1, 5 5 5)') returns 1.4142135623730951<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Which is the same answer as <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>SELECT ST_3DDistance(ST_GeomFromText('MULTIPOINT(1 3 2, 0 0 0)'), ST_GeomFromText('LINESTRING(0 0 0, 5 5 5)'))<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From:</b> Regina Obe <lr@pcorp.us> <br><b>Sent:</b> Tuesday, December 26, 2023 2:46 PM<br><b>To:</b> 'PostGIS Users Discussion' <postgis-users@lists.osgeo.org><br><b>Cc:</b> 'Dapeng Wang' <wangdapeng20191008@gmail.com><br><b>Subject:</b> RE: [postgis-users] Operator does not exist: <<#>><o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I concur doesn’t seem to exist. I’m trying to think how that would ever have been different from <#>.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I recall there was a time before we had true KNN for geometry that one was for bounding box distance and one was for the centroid bounding box distance.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Anyway I’ll remove from the docs. Thanks for catching.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Regina<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From:</b> postgis-users <<a href="mailto:postgis-users-bounces@lists.osgeo.org">postgis-users-bounces@lists.osgeo.org</a>> <b>On Behalf Of </b>Dapeng Wang via postgis-users<br><b>Sent:</b> Monday, December 25, 2023 10:31 PM<br><b>To:</b> <a href="mailto:postgis-users@lists.osgeo.org">postgis-users@lists.osgeo.org</a><br><b>Cc:</b> Dapeng Wang <<a href="mailto:wangdapeng20191008@gmail.com">wangdapeng20191008@gmail.com</a>><br><b>Subject:</b> [postgis-users] Operator does not exist: <<#>><o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hello everyone,<br><br>SELECT st_distance(geom, 'SRID=4326;POINT(1 2)'::geometry)<br>FROM ne_110m_admin_0_countries<br>ORDER BY (ST_GeomFromText('POINT(1 2)') <<#>> geom)<br>operator does not exist: geometry <<#>> geometry<br>Reference <a href="https://postgis.net/docs/manual-dev/en/geometry_distance_box_nd.html">https://postgis.net/docs/manual-dev/en/geometry_distance_box_nd.html</a><o:p></o:p></p><div><p class=MsoNormal><br>Checked the <a href="http://postgis.sql.in">postgis.sql.in</a> source code definition and did not find this operator. Has it been abandoned?<br><br>Thanks,<br>Dapeng<o:p></o:p></p></div></div></div></div></div></body></html>