Cell Size Change

Rick Thompson rick at cast.uark.edu
Wed Sep 14 21:21:19 EDT 1994


Hi, Gary, 
> 
> I would like to know how to change the cell size of a map.  If it is a raster-
> ized vector map, must I go to g.region and specify there, then re rasterize?

To change the cell size from 100 to 50, use g.region res=50 , then run 
r.resample in=oldmap out=newmap. This will give you a newmap at 50 unit 
resolution. This scenario only gives you a new cellfile at 50 units cell size-
the data of course is no better. If you have the original vector file, then
running v.to.rast at the desired resolution will improve the raster file 
compared to the old one. If you do not have the original vector file, then
run r.thin followed by r.poly -l to get smoother vector polygons or r.thin then
r.line for converting  raster lines to vector. Follow with v.to.rast at desired
resolution. Rick
------------------------------------------------------------------------
Rick Thompson-   Research Assistant           E-mail: rick at cast.uark.edu
Center for Advanced Spatial Technologies      Telephone: (501) 575-5736
Ozark Hall Rm. 12                             Fax: 575-3846 
University of Arkansas              
Fayetteville, AR 72701



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