new alpha-test version of r.flow

After extensive re-engineering, r.flow is available for testing by the
GRASS community.

r.flow generates flowlines using a combined raster-vector
approach from an input elevation raster map elevin, and
optionally an input aspect raster map aspin and/or an input
barrier raster map barin. There are three possible output
maps which can be produced in any combination
simultaneously: a vector file flout of flowlines, a raster
map lgout of flowpath lengths, and a raster map dsout of
flowline densities.

Among the improvements to the program are great savings in execution time,
the ability to handle virtually any size file, internal aspect computation,
three-dimensional lengths if desired, better diagnostic output, and minor
geometric corrections. Find this program at

  ftp://moon.cecer.army.mil/grass/incoming/r.flow.tar.Z

A man page is included. Install the program using the command

  gmake4.1

or the man page with

  gmake4.1 . man

or both with

  gmake4.1 . all

Enjoy!
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caplan@cs.uiuc.edu | Joshua Caplan
                        | Department of Computer Science
                        | University of Illinois at Urbana-Champaign
      &
j-caplan@cecer.army.mil | USACERL, Visualization Group
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