NAME¶
r.spreadpath - Recursively traces the least cost path backwards to
cells from which the cumulative cost was determined.
KEYWORDS¶
raster, fire
SYNOPSIS¶
r.spreadpath
r.spreadpath help
r.spreadpath [-
v]
x_input=
string
y_input=
string [
coordinate=
x,y[,
x,y,...]]
output=
string [--
overwrite] [--
verbose]
[--
quiet]
Flags:¶
- -v
-
Run verbosely
- --overwrite
-
Allow output files to overwrite existing files
- --verbose
-
Verbose module output
- --quiet
-
Quiet module output
Parameters:¶
- x_input=string
-
Name of raster map containing back-path easting information
- y_input=string
-
Name of raster map containing back-path northing information
- coordinate=x,y[,x,y,...]
-
The map E and N grid coordinates of starting points
- output=string
-
Name of spread path raster map
DESCRIPTION¶
r.spreadpath recursively traces the least cost path backwards to the
origin, given backlink information input map layers and target locations from
where paths are to be traced. The backlink information map layers record each
cell's backlink UTM northing (the y_input) and easting (the x_input)
coordinates from which the cell's cumulative cost was determined.
The backlink inputs can be generated from another GRASS raster program
r.spread. One of the major applications of
r.spreadpath along
with
r.spread is to accurately find the least cost corridors and/or
paths on a raster setting. More information on
r.spread and
r.spreadpath can be found in Xu (1994).
Parameters:¶
- x_input=name
-
Name of input raster map layer containing backlink UTM easting
coordinates.
- y_input=name
-
Name of input raster map layer containing backlink UTM northing
coordinates.
- coordinate=x,y[,x,y,x,y, ...]
-
Each x,y coordinate pair gives the easting and northing (respectively)
geographic coordinates of a target point from which to backwards trace the
least cost path. As many points as desired can be entered by the
user.
- output=name
-
Name of raster map layer to contain output. Also can be used as the map
layer of the input target points. If so used, the input target point map
will be overwritten by the output.
SEE ALSO¶
r.spread,
r.ros
REFERENCES¶
Xu, Jianping, 1994, Simulating the spread of wildfires using a geographic
information system and remote sensing, Ph. D. Dissertation, Rutgers
University, New Brunswick, New Jersey.
AUTHOR¶
Jianping Xu and Richard G. Lathrop, Jr., Center for Remote Sensing and Spatial
Analysis, Rutgers University.
Last changed: $Date: 2003-05-06 18:41:37 +0200 (Tue, 06 May 2003) $
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