.TH r.surf.fractal 1grass "" "GRASS 6.4.2" "Grass User's Manual" .SH NAME \fI\fBr.surf.fractal\fR\fR - Creates a fractal surface of a given fractal dimension. .SH KEYWORDS raster, DEM, fractal .SH SYNOPSIS \fBr.surf.fractal\fR .br \fBr.surf.fractal help\fR .br \fBr.surf.fractal output\fR=\fIname\fR [\fBdimension\fR=\fIfloat\fR] [\fBnumber\fR=\fIinteger\fR] [--\fBoverwrite\fR] [--\fBverbose\fR] [--\fBquiet\fR] .SS Flags: .IP "\fB--overwrite\fR" 4m .br Allow output files to overwrite existing files .IP "\fB--verbose\fR" 4m .br Verbose module output .IP "\fB--quiet\fR" 4m .br Quiet module output .PP .SS Parameters: .IP "\fBoutput\fR=\fIname\fR" 4m .br Name for output raster map .IP "\fBdimension\fR=\fIfloat\fR" 4m .br Fractal dimension of surface (2 < D < 3) .br Default: \fI2.05\fR .IP "\fBnumber\fR=\fIinteger\fR" 4m .br Number of intermediate images to produce .br Default: \fI0\fR .PP .SH DESCRIPTION \fBr.surf.fractal\fR creates a fractal surface of a given fractal dimension. Uses spectral synthesis method. Can create intermediate layers showing the build up of different spectral coefficients (see Saupe, pp.106-107 for an example of this). .PP Use this module to generate naturally looking synthetical elevation models (DEM). .SH NOTE This module requires the FFTW library for computing Discrete Fourier Transforms. .SH REFERENCE Saupe, D. (1988) Algorithms for random fractals, in Barnsley M., Devaney R., Mandelbrot B., Peitgen, H-O., Saupe D., and Voss R. (1988) The Science of Fractal Images, Ch. 2, pp.71-136. London: Springer-Verlag. .SH SEE ALSO \fIr.surf.contour\fR, \fIr.surf.idw\fR, \fIr.surf.gauss\fR, \fIr.surf.random\fR, \fIr.surf.idw2\fR, \fIv.surf.idw\fR, \fIv.surf.rst\fR .SH AUTHOR Jo Wood, Midlands Regional Research Laboratory (ASSIST), University of Leicester .PP \fILast changed: $Date: 2008-12-06 23:39:43 +0100 (Sat, 06 Dec 2008) $\fR .PP Full index .PP © 2003-2011 GRASS Development Team