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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>See answers below. No trouble at all. Thanks for catching all these loose ends in the docs.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Much appreciated,<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> Dapeng Wang <wangdapeng20191008@gmail.com> <br><b>Sent:</b> Tuesday, December 26, 2023 10:26 PM<br><b>To:</b> Regina Obe <lr@pcorp.us><br><b>Cc:</b> PostGIS Users Discussion <postgis-users@lists.osgeo.org><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><div><div><p class=MsoNormal>I get it, <<#>> is deprecated.<br><<->>Supports 2D and 3D operations, shortest distance.<br>I also verified via SQL that <<->> is indeed the shortest distance.<br><br>There are 2 questions here,<br>1. The centroid algorithm disappears.<o:p></o:p></p><p class=MsoNormal><b><i>[Regina Obe] </i></b> <span style='font-size:12.0pt;font-family:"Courier New"'>Yes this disappears, and is replaced with true distance</span><br>2. How to calculate bounding box distance used in 3D? Initially use <<#>>.<o:p></o:p></p><p class=MsoNormal><b><i>[Regina Obe] </i></b> <span style='font-size:12.0pt;font-family:"Courier New"'>You’d have to cast, if you really wanted to, using geom::box3d, but in practice I don’t think it’s that useful to have bounding box distance. We had it because that was all we could get out of KNN at the time.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:12.0pt;font-family:"Courier New"'><o:p> </o:p></span></p><p class=MsoNormal> (Please don't increase the team's development time because of my question, I have no real application, just learning).<br><br>SELECT ST_GeomFromText('MULTIPOINT(1 3 2, 0 0 0)') <<->> ST_GeomFromText('LINESTRING(1 1 1, 5 5 5)') returns 1.4142135623730951<br>SELECT ST_3DDistance(ST_GeomFromText('MULTIPOINT(1 3 2, 0 0 0)'), ST_GeomFromText('LINESTRING(0 0 0, 5 5 5)'))<br>Haha, the LINESTRING data of the ST_3DDistance function should be LINESTRING(1 1 1, 5 5 5), which is unintentional.<b><i><o:p></o:p></i></b></p></div></div></div></div></body></html>