r.param.scale(1grass)

1r.param.scale(1)              Grass User's Manual             r.param.scale(1)
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NAME

6       r.param.scale  - Extracts terrain parameters from a DEM.
7       Uses  a  multi-scale approach by taking fitting quadratic parameters to
8       any size window (via least squares).
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KEYWORDS

11       raster, geomorphology, terrain, elevation, landform
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SYNOPSIS

14       r.param.scale
15       r.param.scale --help
16       r.param.scale  [-c]  input=name  output=name    [slope_tolerance=float]
17       [curvature_tolerance=float]   [size=integer]   [method=string]   [expo‐
18       nent=float]    [zscale=float]    [--overwrite]   [--help]   [--verbose]
19       [--quiet]  [--ui]
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21   Flags:
22       -c
23           Constrain model through central window cell
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25       --overwrite
26           Allow output files to overwrite existing files
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28       --help
29           Print usage summary
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31       --verbose
32           Verbose module output
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34       --quiet
35           Quiet module output
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37       --ui
38           Force launching GUI dialog
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40   Parameters:
41       input=name [required]
42           Name of input raster map
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44       output=name [required]
45           Name for output raster map containing morphometric parameter
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47       slope_tolerance=float
48           Slope tolerance that defines a ’flat’ surface (degrees)
49           Default: 1.0
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51       curvature_tolerance=float
52           Curvature tolerance that defines ’planar’ surface
53           Default: 0.0001
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55       size=integer
56           Size of processing window (odd number only)
57           Options: 3-499
58           Default: 3
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60       method=string
61           Morphometric parameter in ’size’ window to calculate
62           Options:  elev,  slope,  aspect, profc, planc, longc, crosc, minic,
63           maxic, feature
64           Default: elev
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66       exponent=float
67           Exponent for distance weighting (0.0-4.0)
68           Default: 0.0
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70       zscale=float
71           Vertical scaling factor
72           Default: 1.0
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DESCRIPTION

75       r.param.scale extracts terrain  parameters  from  a  digital  elevation
76       model.  Uses  a  multi-scale  approach by fitting a bivariate quadratic
77       polynomial to a given window size using least squares.
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79       The module calculates the following  parameters  (terminology  is  from
80       Wood,  1996 with related terminology used in other GRASS modules listed
81       in brackets):
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83           ·   elev: Generalised elevation value (for resampling  purposes  at
84               different scale)
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86           ·   slope: Magnitude of maximum gradient (steepest slope angle)
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88           ·   aspect:  Direction  of  maximum gradient (steepest slope direc‐
89               tion=flow direction)
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91           ·   profc: profile curvature (curvature intersecting with the plane
92               defined  by  Z  axis  and maximum gradient direction). Positive
93               values describe convex profile curvature, negative values  con‐
94               cave profile curvature.
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96           ·   planc:  plan curvature (horizontal curvature, intersecting with
97               the XY plane)
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99           ·   longc: longitudinal curvature (profile  curvature  intersecting
100               with the plane defined by the surface normal and maximum gradi‐
101               ent direction)
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103           ·   crosc: cross-sectional curvature (tangential  curvature  inter‐
104               secting with the plane defined by the surface normal and a tan‐
105               gent to the contour - perpendicular to maximum gradient  direc‐
106               tion)
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108           ·   maxic: maximum curvature (can be in any direction)
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110           ·   minic:  minimum  curvature  (in  direction perpendicular to the
111               direction of of maximum curvature)
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113           ·   feature: Morphometric features: peaks,  ridges,  passes,  chan‐
114               nels, pits and planes
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NOTES

117       In  r.param.scale  the direction of maximum gradient (considered downs‐
118       lope) is stored as (West is 0 degree, East is +/- 180 degree):
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120           ·   0..+180 degree from West to North to East
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122           ·   0..-180 degree from West to South to East
123       Note that the aspect map is calculated differently from r.slope.aspect.
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EXAMPLE

126       The next commands will create a geomorphological map of  the  Spearfish
127       sample dataset region:
128       g.region raster=elevation.10m -p
129       r.param.scale in=elevation.10m output=morphology method=feature size=9
130       Figure: Geomorphological map of a subregion in the Spearfish (SD) area
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TODO

133       Fix  bug  when `constrain through central cell’ option selected. Create
134       color tables for all output files (presently only on features).
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REFERENCES

137           ·   Wood, J. (1996): The Geomorphological characterisation of Digi‐
138               tal  Elevation  Models. Diss., Department of Geography, Univer‐
139               sity of Leicester, U.K
140               online at: http://hdl.handle.net/2381/34503
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142           ·   Java Code in LandSerf that implements the same procedure
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AUTHORS

148       jwo@le.ac.uk - ASSIST’s home
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150       Update to FP 3/2002: L. Potrich, M. Neteler, S. Menegon (ITC-irst)
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152       Last changed: $Date: 2017-11-03 17:43:02 +0100 (Fri, 03 Nov 2017) $
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SOURCE CODE

155       Available at: r.param.scale source code (history)
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157       Main index | Raster index | Topics index | Keywords index  |  Graphical
158       index | Full index
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160       © 2003-2019 GRASS Development Team, GRASS GIS 7.6.0 Reference Manual
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164GRASS 7.6.0                                                   r.param.scale(1)