[postgis-tickets] [PostGIS] #2238: [raster]: Clarify meaning of neighborhood width/height (distance in 2.1)

[PostGIS]

#2238: [raster]: Clarify meaning of neighborhood width/height (distance in 2.1)
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 Reporter:  robe    |       Owner:  dustymugs    
     Type:  defect  |      Status:  new          
 Priority:  medium  |   Milestone:  PostGIS 2.0.4
Component:  raster  |     Version:  trunk        
 Keywords:          |  
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 I guess I don't use the neighborhood map algebra functions much.  Leo
 asked what our convention is for neighborhood width/height (distance)

 is it distance from reference cell or the total width/height that includes
 the center cell (which would seem to make it always odd)


 I realized I embarassingly don't know the answer and just assumed it was
 radius (distance from center). Our docs don't help much. They are
 ambiguous.

 I always assumed we measured as distance from reference cell so

 2,2 --> means a matrix of 5x5  11011 (where 0 is the center cell)

 but other stuff I've read seems to contradict that assumption and define
 it as the total width/height (5x5)

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Ticket URL: <http://trac.osgeo.org/postgis/ticket/2238>
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