Aggregation problems

[Michael Shapiro]

d.rast does a double resampling. First it reads the raster map thru
the current region (resampling as it does this according to the rule
described below). Then it resamples again to fit the image to the number of
pixels on the screen. It uses same kind of resampling as the first
to do this.

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|> GRASS ALWAYS resamples as follows: go to the center of  the  grid
|> cell  for  the  current region, compute the coordinates, find the
|> grid cell that contains these coordinates, look in  the  map  and
|> extract the value in that grid cell and that value represents the
|> value for the "output" grid cell for the current region.
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|Well, I'm glad that it works this way and that my first assumption was
|wrong, because this is the way I like it to be.  This will open up some
|new possibilities for me.
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|Is the resampling that d.rast is doing from the cell file to the screen
|pixels working the same way ?
|
|Lars
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|Lars Schylberg                    Email: larss at fmi.kth.se  
|Department of Photogrammetry 
|Royal Institute of Technology     Tel.   +46 8 790 86 33   
|S-100 44  STOCKHOLM, SWEDEN       Fax.   +46 8 790 66 10
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Michael Shapiro                        U.S. Army CERL                  
email:   shapiro at zorro.cecer.army.mil  Environmental Division          
phone:   (217) 373-7277                P.O. Box 9005                   
fax:     (217) 373-7222                Champaign, Ill. 61826-9005
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