Thank you Daniel. I installed grass 7 but my rasters will not display. Strange. 
Will wait to see if others with macs have encountered this problem.
Until then your solution sounds good and will give it a gob tomorrow.

Best wishes,

Raphael.

Sent from my mobile device

On 23 Jul 2014, at 10:04 pm, "Daniel Victoria" 
<[email protected]<mailto:[email protected]>> wrote:

Hi Raphael,

I do recommend upgrading and going the way Anna mentioned, especially if you 
are dealing with a large number of maps. But if that is not an option here are 
the steps I'd take:

1) run r.info<http://r.info> -r on each map to get the min/max range
2) user r.colors with one of the maps and the rule option to set you color 
table to that map. Your rules might look something like this
min_value red
(max - min)/2 yellow
max_value blue
end
-- by substituting the min / max in the above you get a colortable going from 
red to blue with yellow in the middle
3) copy the color table you just set to the other maps using r.color rast 
option. Take a look at r.color man page for more info
http://grass.osgeo.org/grass64/manuals/r.colors.html

Daniel


On Tue, Jul 22, 2014 at 11:46 PM, 
<[email protected]<mailto:[email protected]>> 
wrote:
Thank you Daniel and Anna for the suggestions.
Daniel, I wonder how I might display the ‘common’ colour legend when 
visualising the maps?
When the maps are visualised, the colour legend changes to the min max of the 
current map displayed.

Anna, I use GRASS 6.4.2 – so I guess I should upgrade…

Thank you again.
Raphael.


__________________________
Raphael VISCARRA ROSSEL | Principal Research Scientist | CSIRO Land and Water | 
Bruce E. Butler Laboratory, Clunies Ross St, Black Mountain, Acton ACT 2601 | 
PO BOX 1666 Canberra ACT 2600 | t. +61 2 6246 5945<tel:%2B61%202%206246%205945> 
| m. +61 467 769 364<tel:%2B61%20467%20769%20364> | Chair International Union 
of Soil Science Working Group on Proximal Soil Sensing | 
www.researcherid.com/rid/B-4061-2011<http://www.researcherid.com/rid/B-4061-2011>
 | 
scholar.google.com.au/citations?hl=en&user=KpJdvKEAAAAJ<http://scholar.google.com.au/citations?hl=en&user=KpJdvKEAAAAJ>



From: Anna Petrášová <[email protected]<mailto:[email protected]>>
Date: Wednesday, 23 July 2014 12:15 pm
To: Daniel Victoria 
<[email protected]<mailto:[email protected]>>
Cc: "Viscarra Rossel, Raphael (L&W, Black Mountain)" 
<[email protected]<mailto:[email protected]>>, 
grass <[email protected]<mailto:[email protected]>>
Subject: Re: [GRASS-user] create a common colour scale

Hi,

in case you use GRASS 7, r.colors accepts multiple maps or a file with the map 
names. So this should do it:
r.colors map=precip1,precip2,precip3 color=precipitation

Also, have a look at temporal modules (GRASS 7 only). You can register the 
series of maps as a dataset (t.create, t.register) and then you can easily get 
the min, max values for the entire series and there is also t.rast.colors.

Anna


On Tue, Jul 22, 2014 at 9:41 PM, Daniel Victoria 
<[email protected]<mailto:[email protected]>> wrote:
Hi Raphael,

This is what I did some time ago when I had the same problem
1) Find out the overall minimun and maximum precipitation over all maps.
2) Use r.colors with the rules option to compose a colortable that cover my 
entire precip range.
3) Apply the same colortable to all maps
4) plot and be happy

Hope it helps
Daniel


On Tue, Jul 22, 2014 at 10:01 PM, 
<[email protected]<mailto:[email protected]>> 
wrote:
Hello
I wonder if anyone knows how to create a common colour scale for different 
raster maps?
I want to display all six maps on the same page with the single colour scale 
but I cannot find how to do this in GRASS.

More specifically, I have six raster maps of rainfall for different time 
periods (each has a different range of values) and I would like to display them 
all with the same colour scale. The colour scale needs to be constructed using 
the min and max values of the set of six maps (and not just individual maps.

Will appreciate any input please. Thank you,

Raphael.

__________________________
Raphael VISCARRA ROSSEL | Principal Research Scientist | CSIRO Land and Water | 
Bruce E. Butler Laboratory, Clunies Ross St, Black Mountain, Acton ACT 2601 | 
PO BOX 1666 Canberra ACT 2600 | t. +61 2 6246 5945<tel:%2B61%202%206246%205945> 
| m. +61 467 769 364<tel:%2B61%20467%20769%20364> | Chair International Union 
of Soil Science Working Group on Proximal Soil Sensing | 
www.researcherid.com/rid/B-4061-2011<http://www.researcherid.com/rid/B-4061-2011>
 | 
scholar.google.com.au/citations?hl=en&user=KpJdvKEAAAAJ<http://scholar.google.com.au/citations?hl=en&user=KpJdvKEAAAAJ>



_______________________________________________
grass-user mailing list
[email protected]<mailto:[email protected]>
http://lists.osgeo.org/mailman/listinfo/grass-user


_______________________________________________
grass-user mailing list
[email protected]<mailto:[email protected]>
http://lists.osgeo.org/mailman/listinfo/grass-user


_______________________________________________
grass-user mailing list
[email protected]
http://lists.osgeo.org/mailman/listinfo/grass-user

Reply via email to