⚠️Mlennert at 10:45, 19 September 2012

2012-09-19T10:45:44Z

← Older revision		Revision as of 10:45, 19 September 2012
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	<source lang="bash">		<source lang="bash">
	# get rows and cols as environment variables		# In a shell get rows and cols as environment variables
	eval `g.region -g`		eval `g.region -g`

	# ~~generate~~ the ~~grid~~		#(or just note the output of g.region -p and replace either $rows or $cols in the formulas below)
	r.~~mapcalc "grid_seq = col() * $rows + row() + $cols~~ - ($rows + $cols)"

			# generate the a vertical grid (see image below)
			r.mapcalc "grid_seq = col() * $rows + row() - $rows"

			#or generate a horizontal grid
			r.mapcalc "grid_seq = row() * $cols + col() - $cols"

			#to visualise the category numbers in the grid
	d.mon x0		d.mon x0
	d.rast.num grid_seq		d.rast.num grid_seq
	</source>		</source>

	The resulting raster map looks like this:		The resulting raster map of a vertical grid looks like this:

	[[File:Raster_grid_seq.png\|300px\|thumb\|left\|Sequentially numbered raster grid]]		[[File:Raster_grid_seq.png\|300px\|thumb\|left\|Sequentially numbered raster grid]]

	[[Category: FAQ]]		[[Category: FAQ]]

Neteler: new

2012-09-17T19:38:08Z

new

New page

'''Q:''' How to generate a grid where the cell numbers are sequential?

'''A:''' You can use {{cmd|g.region}} and {{cmd|r.mapcalc}} for this:

<source lang="bash">
# get rows and cols as environment variables
eval `g.region -g`

# generate the grid
r.mapcalc "grid_seq = col() * $rows + row() + $cols - ($rows + $cols)"

d.mon x0
d.rast.num grid_seq
</source>

The resulting raster map looks like this:

[[File:Raster_grid_seq.png|300px|thumb|left|Sequentially numbered raster grid]]

[[Category: FAQ]]

Generate a grid with sequential numbers - Revision history

⚠️Mlennert at 10:45, 19 September 2012

Neteler: new