.TH r.param.scale 1grass "" "GRASS 7.8.5" "GRASS GIS User's Manual" .SH NAME \fI\fBr.param.scale\fR\fR \- Extracts terrain parameters from a DEM. .br Uses a multi\-scale approach by taking fitting quadratic parameters to any size window (via least squares). .SH KEYWORDS raster, geomorphology, terrain, elevation, landform .SH SYNOPSIS \fBr.param.scale\fR .br \fBr.param.scale \-\-help\fR .br \fBr.param.scale\fR [\-\fBc\fR] \fBinput\fR=\fIname\fR \fBoutput\fR=\fIname\fR [\fBslope_tolerance\fR=\fIfloat\fR] [\fBcurvature_tolerance\fR=\fIfloat\fR] [\fBsize\fR=\fIinteger\fR] [\fBmethod\fR=\fIstring\fR] [\fBexponent\fR=\fIfloat\fR] [\fBzscale\fR=\fIfloat\fR] [\-\-\fBoverwrite\fR] [\-\-\fBhelp\fR] [\-\-\fBverbose\fR] [\-\-\fBquiet\fR] [\-\-\fBui\fR] .SS Flags: .IP "\fB\-c\fR" 4m .br Constrain model through central window cell .IP "\fB\-\-overwrite\fR" 4m .br Allow output files to overwrite existing files .IP "\fB\-\-help\fR" 4m .br Print usage summary .IP "\fB\-\-verbose\fR" 4m .br Verbose module output .IP "\fB\-\-quiet\fR" 4m .br Quiet module output .IP "\fB\-\-ui\fR" 4m .br Force launching GUI dialog .SS Parameters: .IP "\fBinput\fR=\fIname\fR \fB[required]\fR" 4m .br Name of input raster map .IP "\fBoutput\fR=\fIname\fR \fB[required]\fR" 4m .br Name for output raster map containing morphometric parameter .IP "\fBslope_tolerance\fR=\fIfloat\fR" 4m .br Slope tolerance that defines a \(cqflat\(cq surface (degrees) .br Default: \fI1.0\fR .IP "\fBcurvature_tolerance\fR=\fIfloat\fR" 4m .br Curvature tolerance that defines \(cqplanar\(cq surface .br Default: \fI0.0001\fR .IP "\fBsize\fR=\fIinteger\fR" 4m .br Size of processing window (odd number only) .br Options: \fI3\-499\fR .br Default: \fI3\fR .IP "\fBmethod\fR=\fIstring\fR" 4m .br Morphometric parameter in \(cqsize\(cq window to calculate .br Options: \fIelev, slope, aspect, profc, planc, longc, crosc, minic, maxic, feature\fR .br Default: \fIelev\fR .IP "\fBexponent\fR=\fIfloat\fR" 4m .br Exponent for distance weighting (0.0\-4.0) .br Default: \fI0.0\fR .IP "\fBzscale\fR=\fIfloat\fR" 4m .br Vertical scaling factor .br Default: \fI1.0\fR .SH DESCRIPTION \fIr.param.scale\fR 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. .PP The module calculates the following parameters (terminology is from Wood, 1996 with related terminology used in other GRASS modules listed in brackets): .RS 4n .IP \(bu 4n \fIelev\fR: Generalised elevation value (for resampling purposes at different scale) .IP \(bu 4n \fIslope\fR: Magnitude of maximum gradient (steepest slope angle) .IP \(bu 4n \fIaspect\fR: Direction of maximum gradient (steepest slope direction=flow direction) .IP \(bu 4n \fIprofc\fR: profile curvature (curvature intersecting with the plane defined by \fIZ\fR axis and maximum gradient direction). Positive values describe convex profile curvature, negative values concave profile curvature. .IP \(bu 4n \fIplanc\fR: plan curvature (horizontal curvature, intersecting with the \fIXY\fR plane) .IP \(bu 4n \fIlongc\fR: longitudinal curvature (profile curvature intersecting with the plane defined by the surface normal and maximum gradient direction) .IP \(bu 4n \fIcrosc\fR: cross\-sectional curvature (tangential curvature intersecting with the plane defined by the surface normal and a tangent to the contour \- perpendicular to maximum gradient direction) .IP \(bu 4n \fImaxic\fR: maximum curvature (can be in any direction) .IP \(bu 4n \fIminic\fR: minimum curvature (in direction perpendicular to the direction of of maximum curvature) .IP \(bu 4n \fIfeature\fR: Morphometric features: peaks, ridges, passes, channels, pits and planes .RE .SH NOTES In \fIr.param.scale\fR the direction of maximum gradient (considered downslope) is stored as (West is 0 degree, East is +/\- 180 degree): .RS 4n .IP \(bu 4n 0..+180 degree from West to North to East .IP \(bu 4n 0..\-180 degree from West to South to East .RE Note that the aspect map is calculated differently from \fIr.slope.aspect\fR. .SH EXAMPLE The next commands will create a geomorphological map of the Spearfish sample dataset region: .br .nf \fC g.region raster=elevation.10m \-p r.param.scale in=elevation.10m output=morphology method=feature size=9 \fR .fi .br \fIFigure: Geomorphological map of a subregion in the Spearfish (SD) area\fR .SH TODO Fix bug when \(gaconstrain through central cell\(cq option selected. Create color tables for all output files (presently only on features). .SH REFERENCES .RS 4n .IP \(bu 4n Wood, J. (1996): The Geomorphological characterisation of Digital Elevation Models. Diss., Department of Geography, University of Leicester, U.K .br online at: http://hdl.handle.net/2381/34503 .IP \(bu 4n Java Code in LandSerf that implements the same procedure .RE .SH SEE ALSO \fI r.geomorphon, r.slope.aspect \fR .SH AUTHORS jwo@le.ac.uk \- ASSIST\(cqs home .PP Update to FP 3/2002: L. Potrich, M. Neteler, S. Menegon (ITC\-irst) .SH SOURCE CODE .PP Available at: r.param.scale source code (history) .PP Main index | Raster index | Topics index | Keywords index | Graphical index | Full index .PP © 2003\-2020 GRASS Development Team, GRASS GIS 7.8.5 Reference Manual