---
name: "r.surf.random"
section: "1grass"
platform: "linux"
package: "grass-doc"
version: "8.4.1-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/r.surf.random"
---

# r.surf.random(1grass)

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

## 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 for random number generator\
   The same seed can be used to obtain same results or random seed can be generated by other means.

## 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)

Accessed: Monday Feb 24 17:50:54 2025

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