r.surf.random(1)

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
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.

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

SEE ALSO
r.random.surface, r.surf.contour, r.surf.fractal, r.surf.gauss, r.surf.idw, v.surf.rst

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 May 08 20:58:05 2025 in commit: 4144ba81fa125e1549fc52e1cf5feb4fa004be8b

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