[GRASS-user] Region Definition in GRASS

[Glynn Clements]

Pedro Roma wrote:

> Ok but for instance. If my region is defined with a Spatial Resolution of
> 1kilometer and, if I do some r.mapcalc with two LANDSAT images, the output
> image will have which one of the resolutions? the Region or the 2 landsat
> images?

The region.

Most raster modules (including r.mapcalc) generate maps with the
bounds and resolution of the current region. Input maps are cropped,
padded and/or resampled to the current region, so all processing
within the module takes place on the grid defined by the current
region.

The main exceptions are the r.in.* modules, which import files
cell-for-cell, using the bounds specified in the file's metadata if
present. The current region is ignored.

Modules which perform their own resampling (e.g. r.resamp.*, r.proj)
create output maps according to the current region but read their
input maps without cropping or resampling.

-- 
Glynn Clements <glynn at gclements.plus.com>