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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C">Hi List,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C">I have sets of points (up to 250,000 in a set) and I want to get the furthest distance between any of them.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C">In theory the simplest way is to use ST_MinimumBoundingCircle(ST_Collect(geography) and then get the diameter of that.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C">The problem is – I don’t seem to be able to get the diameter of that circle (which would give me the distance I want).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C">Does anyone have any thoughts on this? Is there a good way to get the diameter? Or some other way of getting the distance I desire.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C">Thanks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#3C3C3C">Jonathan<o:p></o:p></span></p>
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