GRASS logo

NAME

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

KEYWORDS

raster, geomorphology, terrain, elevation, landform

SYNOPSIS

r.param.scale
r.param.scale --help
r.param.scale [-c] input=name output=name [slope_tolerance=float] [curvature_tolerance=float] [size=integer] [method=string] [exponent=float] [zscale=float] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-c
Constrain model through central window cell
--overwrite
Allow output files to overwrite existing files
--help
Print usage summary
--verbose
Verbose module output
--quiet
Quiet module output
--ui
Force launching GUI dialog

Parameters:

input=name [required]
Name of input raster map
output=name [required]
Name for output raster map containing morphometric parameter
slope_tolerance=float
Slope tolerance that defines a 'flat' surface (degrees)
Default: 1.0
curvature_tolerance=float
Curvature tolerance that defines 'planar' surface
Default: 0.0001
size=integer
Size of processing window (odd number only)
Options: 3-499
Default: 3
method=string
Morphometric parameter in 'size' window to calculate
Options: elev, slope, aspect, profc, planc, longc, crosc, minic, maxic, feature
Default: elev
exponent=float
Exponent for distance weighting (0.0-4.0)
Default: 0.0
zscale=float
Vertical scaling factor
Default: 1.0

Table of contents

DESCRIPTION

r.param.scale extracts terrain parameters from a digital elevation model. Uses a multi-scale approach by fitting a bivariate quadratic polynomial to a given window size using least squares.

The module calculates the following parameters (terminology is from Wood, 1996 with related terminology used in other GRASS modules listed in brackets):

NOTES

In r.param.scale the direction of maximum gradient (considered downslope) is stored as (West is 0 degree, East is +/- 180 degree): Note that the aspect map is calculated differently from r.slope.aspect.

EXAMPLE

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

TODO

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

REFERENCES

SEE ALSO

r.slope.aspect

AUTHORS

jwo@le.ac.uk - ASSIST's home

Update to FP 3/2002: L. Potrich, M. Neteler, S. Menegon (ITC-irst)

Last changed: $Date: 2016-12-11 10:03:35 -0800 (Sun, 11 Dec 2016) $

SOURCE CODE

Available at: r.param.scale source code (history)


Main index | Raster index | Topics index | Keywords index | Graphical index | Full index

© 2003-2017 GRASS Development Team, GRASS GIS 7.2.3svn Reference Manual