Problem with r.cost?

[Malcolm Williamson]

Rick Thompson's original question:
> > 
> > Hello Grassers,
> >   Does anyone know why r.cost is behaving so much differently in 4.1 than
> > in 4.0. The manual entry in 4.0 makes sense, but after using 4.1 r.cost,
> 
> 
> Several reasons:
> 	1. 4.0 r.cost figures the cumulative_cost for a to_cell by simply adding
> 	   its cost to the from_cell's; while 4.1 r.cost does it
> 	   by adding the average_cost of the 'from' and 'to' cells to the 
> 	   from_cell's cumulative_cost.
> 	2. *Absolute* cell resolutions are taken into accout by 4.0 r.cost 
> 	   ('normalized' to 100m), not by 4.1 r.cost. 
> 	3. 4.1 r.cost takes more 'neighboring' cells into accout as your 
> 	   request, while 4.0 r.cost doesn't. And ...
> 
> Jianping Xu 
> jianp at ocean.rutgers.edu
> 

This is very handy to know; why doesn't the manual make any mention of these
changes whatsoever?!!

P.S. By the way, Jianping, how did *you* find out about this?

--
Malcolm D. Williamson - Research Assistant       E-mail: malcolm at cast.uark.edu
Center for Advanced Spatial Technologies      Telephone: (501) 575-6159
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University of Arkansas              
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