[GRASS-user] Check if a raster map has any valid pixel

[Glynn Clements]

Kim Besson wrote:

> I have a python script where I need to check if an input raster map has any
> valid pixel (at least one pixel that is not null). How can I check this
> (easy and quick way?) in order to be integrated in my Script?

Check the range:

	$ r.mapcalc --o 'foo = null()'
	$ r.info -r foo
	min=NULL
	max=NULL

The range can only have min=max=NULL if there are no non-null cells.

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