[GRASS-user] How to use r.grow module

GRASS GRASS user
1

Hi everyone,

I’m a new user to grass and can I know how to create a raster map containing one cell using r.grow module. I read the manual but could not understand any.

Thank You,

BR,
Vidura Dantanarayana

2

Hi Vidura,

On 11/10/18 19:15, Vidura Dantanarayana wrote:

Hi everyone,

I'm a new user to grass and can I know how to create a raster map containing one cell using r.grow module. I read the manual but could not understand any.

r.grow is not meant for creating a map with one cell. It creates a sort of buffer around non-null cells in an existing raster map.

To create a new raster map with one cell, you have different options depending on what you have:

- If you have coordinates for the cell, you can use

  - r.in.xyz
  - v.in.ascii to create a vector point and then v.to.rast to transform this to raster.

- If you want to digitize the cell interactively, you can use the raster digitizer (https://grass.osgeo.org/grass74/manuals/wxGUI.rdigit.html)

Whatever you do, make sure you first have a good understanding of the concept of computational region in GRASS GIS as this will determine the nature of your raster.

See

https://grass.osgeo.org/grass74/manuals/rasterintro.html
https://grasswiki.osgeo.org/wiki/Computational_region

for general info and

https://grass.osgeo.org/grass74/manuals/g.region.html

for the module allowing to define the region.

Moritz