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Can anybody explain how to compute mean coordinates?

Regards.

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5  
please clarify your question. What exactly are you try to do and what tools are you using? –  spatialthoughts Jul 24 '12 at 5:50
    
I am using the analysis tool whose name is mean coordinate. –  Mauro Jul 24 '12 at 12:42
    
What software are you using? –  whuber Jul 24 '12 at 12:51
    
I am using Quantum GIS. –  Mauro Jul 24 '12 at 13:08
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This question describes how to compute mean coordinates in QGIS: gis.stackexchange.com/questions/29181/mean-coordinates-in-qgis. Is that what you're looking for? –  whuber Jul 24 '12 at 16:04
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1 Answer

The same way you calculate any mean from a set of numbers. The sum of the numbers divided by the count

Mean x = (X1 + X2 + X3....XN)/N
Mean Y = (Y1 + Y2 + Y3....YN)/N
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I suppose there should be another possibilities, arithmetic mean is only relevant for planar coordinates. –  menjaraz Jul 24 '12 at 9:21
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True, although with the lack of information in the question I just assumed planar. –  Nathan W Jul 24 '12 at 9:41
    
You are right. AFAIC, doing it on the sphere and/or on the ellipse (I think of WGS84) are also relevant. I also think of Delaunay Triangles, Voronoï Diagrams and the more involved computations implied. –  menjaraz Jul 24 '12 at 10:18
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Thanks for the response! In WGS 84 are the same calculations?? Is correct to do this in every coordinate system or projection? –  Mauro Jul 24 '12 at 12:37
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