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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>If the area function is returning square
meters (depends on your projection) then just divide the answer by 4046.896 to
get kilometers.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>All area functions are squared by
definition.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>--Craig<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'> Ethan Alpert
[mailto:ealpert@digitalglobe.com] <br>
<b><span style='font-weight:bold'>Sent:</span></b> Tuesday, September 28, 2004
2:57 PM<br>
<b><span style='font-weight:bold'>To:</span></b> PostGIS Users Discussion<br>
<b><span style='font-weight:bold'>Subject:</span></b> [postgis-users] Computing
area in km^2 from 4326 geometries</span></font><o:p></o:p></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=DE
style='font-size:10.0pt;font-family:Arial;color:blue'>How does one compute
areas in km^2? I was thinking something like
area2d(transform(the_geom,<someEPSG>)). </span></font><span lang=DE><o:p></o:p></span></p>
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<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=DE
style='font-size:10.0pt;font-family:Arial;color:blue'>How do others do this?</span></font><span
lang=DE><o:p></o:p></span></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=DE
style='font-size:12.0pt'> <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=DE
style='font-size:10.0pt;font-family:Arial;color:blue'>Thanks!</span></font><span
lang=DE><o:p></o:p></span></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span lang=DE
style='font-size:12.0pt'> <o:p></o:p></span></font></p>
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<p class=MsoNormal><font size=2 color=blue face=Arial><span lang=DE
style='font-size:10.0pt;font-family:Arial;color:blue'>-e</span></font><span
lang=DE><o:p></o:p></span></p>
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