r.surf.random - GRASS GIS manual

DESCRIPTION
EXAMPLE
SEE ALSO
AUTHOR

NAME

r.surf.random - Produces a raster surface map of uniform random deviates with defined range.

KEYWORDS

raster, surface, random

SYNOPSIS

r.surf.random

r.surf.random --help

r.surf.random [-i] output=name [min=float] [max=float] [seed=integer] [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-i: Create an integer raster map
--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:

output=name [required]: Name for output raster map
min=float: Minimum random value; Default: 0
max=float: Maximum random value; Default: 100
seed=integer: Seed value for the random number generator; Using the same seed ensures identical results, while a randomly generated seed produces different outcomes in each run.

DESCRIPTION
EXAMPLE
SEE ALSO
AUTHOR

DESCRIPTION

r.surf.random produces a raster map layer of uniform random deviates whose range can be expressed by the user. It is essentially the same as r.surf.gauss, but uses a linear random number generator instead. It uses the random number generator drand48() or rand(), depending on the user's platform.

EXAMPLE

g.region -p n=228500 s=215000 w=630000 e=645000 res=10
r.surf.random out=random min=0 max=100

# check result
r.univar random

Figure: Random surface example (min: 10; max: 100)

With the histogram tool the cell values versus count can be shown.

r.random.surface example histogram (min: 10; max: 100)

Figure: Histogram of random surface example (min: 10; max: 100)

AUTHOR

Jo Wood
Midlands Regional Research Laboratory (ASSIST)
University of Leicester
October 1991

SOURCE CODE

Available at: r.surf.random source code (history)

Latest change: Thursday Mar 06 19:23:31 2025 in commit: 5fd4234a4f6ab09eb244c67111a1db2d84b6d0fe