[GRASS-dev] Re: [GRASS GIS] #1584: error in r.walk help page

[GRASS GIS]

#1584: error in r.walk help page
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 Reporter:  hamish  |       Owner:  grass-dev@…              
     Type:  defect  |      Status:  new                      
 Priority:  major   |   Milestone:  6.4.3                    
Component:  Docs    |     Version:  unspecified              
 Keywords:  r.walk  |    Platform:  All                      
      Cpu:  All     |  
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Comment(by dkavanagh):

 Hamish - I believe the help is correct. c and d are multiplied by the
 delta, which in a downward slope will be negative. Here is an example from
 the code - fcost_dtm = (double)((double)(W_dtm - my_dtm) * c);

 Replying to [ticket:1584 hamish]:
 > one from Agustin:
 >
 > {{{
 > the documentation in r.walk is wrong. It says:
 > "The default values for a, b, c, d are those proposed by Langmuir
 > (0.72, 6.0, 1.9998, -1.9998)"
 > and it should say:
 > "The default values for a, b, c, d are those proposed by Langmuir
 > (0.72, 6.0, -1.9998, 1.9998)"
 >
 > because the point is that you go faster on gentle slopes and more
 > slowly on steeper slopes and those values are in m/s
 > The worrying question is whether these values are also wrong in the
 > default values of r.walk.
 > }}}

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Ticket URL: <http://trac.osgeo.org/grass/ticket/1584#comment:3>
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