---
name: "r3.gradient"
section: "1grass"
platform: "linux"
package: "grass-doc"
version: "8.4.1-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/r3.gradient"
---

# r3.gradient(1grass)

Computes gradient of a 3D raster map and outputs gradient components as three 3D raster maps.

## NAME

**r3.gradient**  - Computes gradient of a 3D raster map and outputs gradient components as three 3D raster maps.

## KEYWORDS

raster3d, gradient, voxel

## SYNOPSIS

**r3.gradient**\
 **r3.gradient --help**\
 **r3.gradient** **input**=*name* **output**=*grad\_x,grad\_y,grad\_z*\[,*grad\_x,grad\_y,grad\_z*,...\]  \[**blocksize**=*size\_x,size\_y,size\_z*\[,*size\_x,size\_y,size\_z*,...\]\]   \[--**overwrite**\]  \[--**help**\]  \[--**verbose**\]  \[--**quiet**\]  \[--**ui**\]

### Flags:

- **--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:

- **input**=*name* **\[required\]**

  Name of input 3D raster map

- **output**=*grad\_x,grad\_y,grad\_z\[,grad\_x,grad\_y,grad\_z*,...\] **\[required\]**

  Name for output 3D raster map(s)

- **blocksize**=*size\_x,size\_y,size\_z\[,size\_x,size\_y,size\_z*,...\]

  Size of blocks\
   Default: *30,30,20*

## DESCRIPTION

Module *r3.gradient* computes gradient from a 3D raster map. Results are three 3D raster maps describing the x, y, z components of the computed gradient field.

## EXAMPLES

```
# create a 3D raster
g.region s=0 n=100 w=0 e=100 b=0 t=100 -p
r3.mapcalc "test_gradient = sqrt(row()*row() +col()*col()+ depth()*depth())"
# compute gradient
r3.gradient input=test_gradient output=grad_x,grad_y,grad_z
```

## SEE ALSO

*r3.flow,* *r.flow*

## AUTHOR

Anna Petrasova, NCSU GeoForAll Lab, developed during GSoC 2014.

## SOURCE CODE

Available at: r3.gradient source code (history)

Accessed: Monday Feb 24 17:51:06 2025

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