180 degree offset of r.slope.aspect (& now s.surf.tps)

[Ronald E. Thomas]

Hello fellow GRASSuser's,
Maybe I'm just thick, or still have too much holiday food clogging my arteries,
but I can't understand why r.slope.aspect gives a ZERO value for due east, 
and then counts off counter-clockwise.  Why not start with due north and go
clockwise, just like a trusty Ranger compass? Can anyone explain the reasoning
(or necessity) behind this?
	Also, any hints from anyone on how to adjust an aspect map to a TRUE
AZIMUTH map, besides manual renumbering?
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   Ronald Thomas                         ^  ront at meeker.cfnr.colostate.edu
    Natural Resource Spec. (GIS)         ^  
     Resource Management Division        ^   Phone: 303-586-3565  x285
      Rocky Mountain National Park       ^          700-323-7285  (FTS)
       Estes Park, CO  80517             ^ 
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