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r.surf.random

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

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

Example:

r.surf.random output=name

grass.script.run_command("r.surf.random", output, min=0, max=100, seed=None, flags=None, overwrite=None, verbose=None, quiet=None, superquiet=None)

Example:

gs.run_command("r.surf.random", output="name")

grass.tools.Tools.r_surf_random(output, min=0, max=100, seed=None, flags=None, overwrite=None, verbose=None, quiet=None, superquiet=None)

Example:

tools = Tools()
tools.r_surf_random(output="name")

This grass.tools API is experimental in version 8.5 and expected to be stable in version 8.6.

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.
-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
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

output : str, required
    Name for output raster map
    Used as: output, raster, name
min : float, optional
    Minimum random value
    Default: 0
max : float, optional
    Maximum random value
    Default: 100
seed : int, optional
    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.
flags : str, optional
    Allowed values: i
    i
        Create an integer raster map
overwrite : bool, optional
    Allow output files to overwrite existing files
    Default: None
verbose : bool, optional
    Verbose module output
    Default: None
quiet : bool, optional
    Quiet module output
    Default: None
superquiet : bool, optional
    Very quiet module output
    Default: None

output : str | type(np.ndarray) | type(np.array) | type(gs.array.array), required
    Name for output raster map
    Used as: output, raster, name
min : float, optional
    Minimum random value
    Default: 0
max : float, optional
    Maximum random value
    Default: 100
seed : int, optional
    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.
flags : str, optional
    Allowed values: i
    i
        Create an integer raster map
overwrite : bool, optional
    Allow output files to overwrite existing files
    Default: None
verbose : bool, optional
    Verbose module output
    Default: None
quiet : bool, optional
    Quiet module output
    Default: None
superquiet : bool, optional
    Very quiet module output
    Default: None

Returns:

result : grass.tools.support.ToolResult | np.ndarray | tuple[np.ndarray] | None
If the tool produces text as standard output, a ToolResult object will be returned. Otherwise, None will be returned. If an array type (e.g., np.ndarray) is used for one of the raster outputs, the result will be an array and will have the shape corresponding to the computational region. If an array type is used for more than one raster output, the result will be a tuple of arrays.

Raises:

grass.tools.ToolError: When the tool ended with an error.

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

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

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 4144ba8