[GRASS-user] Re: [GRASS-dev] LiDAR LAS import
Hi Markus, Just compiled again liblas svn trunk, everything is working as expected so far. Thanks heaps for that new functionality, this is really very useful. Pierre 2011/5/25 Markus Metz markus.metz.gisw...@googlemail.com: Hi all, GRASS 7 has a new module v.in.lidar for importing LiDAR LAS files (*.las or *.laz). The LAS file format is commonly used for storing LiDAR point clouds, but is unfortunately not supported by OGR. v.in.lidar uses the libLAS library [0] and is only compiled if the libLAS library is present. I chose to use the library instead of writing a custom LAS reading interface because the current LAS library version 1.6.1 is stable, supports LAS file versions 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, each of which can store LiDAR points in up to 5 different point formats. The user and the interface do not need to know the file version and point format of a given file, all that is conveniently handled by the libLAS library in the background. The library has Large File Support (LFS) and is well tested on different platforms, also with different endian-ness. This functionality is not that easy to replicate. You will need to get the libLAS library and configure GRASS 7 with --with-liblas in order to have the module available. Please test! Markus M [0] http://www.liblas.org ___ grass-dev mailing list grass-...@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-dev -- Scientist Landcare Research, New Zealand ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Installing extension from a local copy of the SVN repo
Pierre wrote: Does anyone managed to use g.extension with a local copy of the SVN repository? I have problems retrieving code from the online repo using g.extension (see ticket #1341), but I can make a svn checkout. Moreover, that could come handy when a network connection is not available. if you have a local checkout of the grass svn source code, and addons svn, then there's no real need to use g.extension. just do: cd /usr/local/src/grass/svn/grass-addons/display/d.mon make MODULE_TOPDIR=/usr/local/src/grass/svn/trunk/ done! To make this easier, I set up an alias like so: alias gmake7='make MODULE_TOPDIR=/usr/local/src/grass/svn/trunk/' so then I just cd into the wanted addons module dir and run `gmake7`. note you'll have to do that again after each 'make distclean' of the main source tree as it installs into the main build dir. If you have run 'sudo make install' for the build, add the word install to the end of the `make` command (+sudo if needed) to install it too. see http://grass.osgeo.org/wiki/Compile_and_Install#Addons Hamish ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] GRASS earth curvature correction (viewsheds, LOS)
Hamish wrote: [...] the ideal solution is to have both curvature and refection corrections implemented as flags in the new improved r.viewshed. [...] Benjamin wrote: That should be really easy to do. All that's needed is to amend the existing correction but taking away 1/7 to account for the adverse effect of refraction. ok, done for r.viewshed in r46423. Number of visible cells reduces slightly when the curvature flag is used, and rebounds ever so slightly when the refraction flag is used. Please test. Well, that refraction correction is really a rough simplification of reality. Essentially, it uses the same amount of correction as ArcGIS. There is some justification for this. You can find links to articles here: http://mapaspects.org/content/effects-curvature-earth-refraction-light-air-and-fuzzy-viewsheds-arcgis-92 I could not get at the Yoeli(1985) article as it's behind a paywall my univ does not subscribe to. Can anyone say what's in it? But in summary, accounting for realistic refraction conditions would be much more complex, as it would also have to take into plus different refraction at different elevations, etc. I don't mind that / it is not so different from the physics I do in my day job, and just using a fudge factor of +1/7th leaves me feeling like the job is poorly done. Passing the coeff off to the user without further guidance seems like a bit of a cop out. I suppose there is a gradient in the coeff as you move from the tropics to high latitudes, daily temperature, Linke factor, humidity, aerosols, etc ... ? But given that most DEMs have an inherent vertical error that is greater than the influence of these effects, can we quantify that? for example what's STRM 95% confidence accuracy? I am not sure it's worth spending too much time on (it might be for very long distance visibility -- I just don't know). it would be good for us to do a rough back of the envelope calc to justify that before fully forgetting about it. I guess for the worst case scenario we could try the views from Mt. Everest and/or Olympus Mons and see what difference it makes. thanks, Hamish ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] GRASS earth curvature correction (viewsheds, LOS)
On Thu, May 26, 2011 at 10:50 AM, Hamish hamis...@yahoo.com wrote: Hamish wrote: [...] the ideal solution is to have both curvature and refection corrections implemented as flags in the new improved r.viewshed. [...] Benjamin wrote: That should be really easy to do. All that's needed is to amend the existing correction but taking away 1/7 to account for the adverse effect of refraction. ok, done for r.viewshed in r46423. Number of visible cells reduces slightly when the curvature flag is used, and rebounds ever so slightly when the refraction flag is used. Please test. Well, that refraction correction is really a rough simplification of reality. Essentially, it uses the same amount of correction as ArcGIS. There is some justification for this. You can find links to articles here: http://mapaspects.org/content/effects-curvature-earth-refraction-light-air-and-fuzzy-viewsheds-arcgis-92 Hm-hm. Citing from the website: The problem is that the ratio of change due to air to curvature is not 1:7 (0.13), as the standard refraction coefficient suggests. It is 0.325. Last spring I put together an Excel sheet that computes this ratio. Having the adjustable details (altitude, air pressure, wavelength, etc.) did show me that the ratio never really changes (given earthly conditions). What it did show me was that the ratio was always 0.325. [...] But given that most DEMs have an inherent vertical error that is greater than the influence of these effects, can we quantify that? for example what's STRM 95% confidence accuracy? From Farr et al. 2007: Summary of SRTM performance. All quantities represent 90% errors in meters. Africa Australia Eurasia Islands N. America S. America Absolute Geolocation Error 11.97.2 8.8 9 12.69 Absolute Height Error 5.6 6 6.2 8 9 6.2 Relative Height Error 9.8 4.7 8.7 6.2 7 5.5 Long Wavelength Height Error3.1 6 2.6 3.7 4 4.9 [sorry for the ugly format, it's tab separated] I am not sure it's worth spending too much time on (it might be for very long distance visibility -- I just don't know). it would be good for us to do a rough back of the envelope calc to justify that before fully forgetting about it. I guess for the worst case scenario we could try the views from Mt. Everest and/or Olympus Mons and see what difference it makes. No need to go into mountains, just increase observer elevation offset, preferably in a moderately flat area to get really far views. Using correction for earth curvature only, max is a bit more than 100 km with 3km observation offset. 200km is impossible without leaving earth's atmosphere. Markus M ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] GRASS earth curvature correction (viewsheds, LOS)
Hm-hm. Citing from the website: The problem is that the ratio of change due to air to curvature is not 1:7 (0.13), as the standard refraction coefficient suggests. It is 0.325. As far as I can tell, this is a mis-understanding. The value 0.325 applies to radio waves. Visible light is very close to 1:7. You can read up on the arguments here: http://forums.esri.com/Thread.asp?c=3f=40t=161962#474778 There is also some more information in that forum thread regarding more realistic modelling of refraction under different atmospheric conditions. I realize the whole discourse is somewhat clouded. But I don't have access to most of the relevant literature for the time being, nor do I have the necessary scientific background -- so any fresh input will be much appreciated! Btw.: using r.ecurv.comp, one can freely specify the atmospheric correction factor. [...] But given that most DEMs have an inherent vertical error that is greater than the influence of these effects, can we quantify that? for example what's STRM 95% confidence accuracy? From Farr et al. 2007: Summary of SRTM performance. All quantities represent 90% errors in meters. Africa Australia Eurasia Islands N. America S. America Absolute Geolocation Error 11.9 7.2 8.8 9 12.6 9 Absolute Height Error 5.6 6 6.2 8 9 6.2 Relative Height Error 9.8 4.7 8.7 6.2 7 5.5 Long Wavelength Height Error 3.1 6 2.6 3.7 4 4.9 [sorry for the ugly format, it's tab separated] What I wold love to see is a method for probabilistic viewsheds, which adds random +/- offsets (within the vertical error range) to the elevation model cells, runs the viewshed computations several times, each time with new random offsets, then outputs the average visibility of each cell after n runs (not sure how best to determine n). That would be much more realistic than those over- confident 0/1 viewsheds. Such a method could even take into account roughly modelled blocks of vegetation or other obstacles for which height is hard to quantify precisely. -- shouldn't be too hard to implement in a little script. Ben I am not sure it's worth spending too much time on (it might be for very long distance visibility -- I just don't know). it would be good for us to do a rough back of the envelope calc to justify that before fully forgetting about it. I guess for the worst case scenario we could try the views from Mt. Everest and/or Olympus Mons and see what difference it makes. No need to go into mountains, just increase observer elevation offset, preferably in a moderately flat area to get really far views. Using correction for earth curvature only, max is a bit more than 100 km with 3km observation offset. 200km is impossible without leaving earth's atmosphere. Markus M -- Files attached to this email may be in ISO 26300 format (OASIS Open Document Format). If you have difficulty opening them, please visit http://iso26300.info for more information. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] GRASS earth curvature correction (viewsheds, LOS)
- Original Message - Hamish wrote: [..] ok, done for r.viewshed in r46423. Number of visible cells reduces slightly when the curvature flag is used, and rebounds ever so slightly when the refraction flag is used. Please test. Cool, that's what one would expect. Reassuring. Well, that refraction correction is really a rough simplification of reality. Essentially, it uses the same amount of correction as ArcGIS. There is some justification for this. You can find links to articles here: http://mapaspects.org/content/effects-curvature-earth-refraction-light-air-and-fuzzy-viewsheds-arcgis-92 I could not get at the Yoeli(1985) article as it's behind a paywall my univ does not subscribe to. Can anyone say what's in it? But in summary, accounting for realistic refraction conditions would be much more complex, as it would also have to take into plus different refraction at different elevations, etc. I don't mind that / it is not so different from the physics I do in my day job, and just using a fudge factor of +1/7th leaves me feeling like the job is poorly done. Passing the coeff off to the user without further guidance seems like a bit of a cop out. I suppose there is a gradient in the coeff as you move from the tropics to high latitudes, daily temperature, Linke factor, humidity, aerosols, etc ... ? I am sure there is. But I lack the background to judge this correctly. But given that most DEMs have an inherent vertical error that is greater than the influence of these effects, can we quantify that? for example what's STRM 95% confidence accuracy? [I think this needs a probabilistic approach, see my other reply to this thread.] I am not sure it's worth spending too much time on (it might be for very long distance visibility -- I just don't know). it would be good for us to do a rough back of the envelope calc to justify that before fully forgetting about it. I guess for the worst case scenario we could try the views from Mt. Everest and/or Olympus Mons and see what difference it makes. -- that would rock :) Ben thanks, Hamish -- Files attached to this email may be in ISO 26300 format (OASIS Open Document Format). If you have difficulty opening them, please visit http://iso26300.info for more information. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] increase performance of i.ortho.photo/i.photo.rectify
Hi, I am orthorectifying 3 channel aerial photographs using i.ortho.photo (GRASS 6.4.1, Ubuntu 10.04 64bit, dual core (each 3 GHz), 4 GB RAM). I'm new to GRASS so no clue whether it's possible to make the rectification process to use the computer's resources better. i.photo.rectify is using at most 30% CPU, processing of one channel takes about 15-20 minutes. I suppose it would be much faster if it would use one core running at 100%. Is there an optimal amount of memory that should be assigned to the process or the more the better? Any suggestions would be more than welcome! Andras ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] GRASS earth curvature correction (viewsheds, LOS)
- Original Message - On Thu, May 26, 2011 at 12:26 PM, Benjamin Ducke benjamin.du...@oxfordarch.co.uk wrote: Hm-hm. Citing from the website: The problem is that the ratio of change due to air to curvature is not 1:7 (0.13), as the standard refraction coefficient suggests. It is 0.325. As far as I can tell, this is a mis-understanding. The value 0.325 applies to radio waves. Visible light is very close to 1:7. What if I am interested in radio waves, not visible light, e.g. for antenna relay positions? IMHO, that refraction coefficient should not be hard-coded. Agreed. It's a settable value in r.ecurv.comp and should also be one in all GRASS modules that have refraction compensation. Ben I realize the whole discourse is somewhat clouded. But I don't have access to most of the relevant literature for the time being, nor do I have the necessary scientific background Me neither. But any correction should take into account that the observer is not necessarily a human without optical equipment (telescope etc), but can also be some technical device, e.g. a sender or receiver of whatever signals. my .2c Markus M -- Files attached to this email may be in ISO 26300 format (OASIS Open Document Format). If you have difficulty opening them, please visit http://iso26300.info for more information. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] GRASS earth curvature correction (viewsheds, LOS)
As far as I can tell, this is a mis-understanding. The value 0.325 applies to radio waves. Visible light is very close to 1:7. What if I am interested in radio waves, not visible light, e.g. for antenna relay positions? IMHO, that refraction coefficient should not be hard-coded. Agreed. It's a settable value in r.ecurv.comp and should also be one in all GRASS modules that have refraction compensation. ok good point, wavelength matters VHF LOS propagation distance is an important problem to model. r.viewshed now has a user settable refection coefficient in the range 0.0-1.0. coeff=0.0 is like no refraction, 1.0 totally cancels out any curvature of the Earth. btw 1/7 is not 0.13, it's ~0.143. (to be picky) Hamish ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] problem installing addons in grass7
Dear list, I gues this is basic stuff but I can't find a solution to install install. When I try to install some addons in grass7, it advise me to install 'install' first. g.extension -l svnurl=https://svn.osgeo.org/grass/grass-addons/grass7 prefix=$GRASS_ADDON_PATH ERROR: install required. Please install 'install' first. Is that related to $GRASS_ADDON_PATH ? I'm on mac intel. Thanks___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] (sans objet)
Bonsoir votre site ne m'interrsse plus, jesuis en France et je ne parle pas anglais. Je vous prierais de ne plus m'adresser vos messages Amicalement ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] (sans objet)
this is about unsubscribing... Utilisez le lien suivant, saisissez votre email dans la case unsubscribe en bas de la page. Le 26/05/2011 21:36, LUCKHAUPT DANIEL a écrit : Bonsoir votre site ne m'interrsse plus, jesuis en France et je ne parle pas anglais. Je vous prierais de ne plus m'adresser vos messages Amicalement ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] (sans objet)
Daniel, --in french, sorry for the exception -- pour résilier votre abonnement à cette liste, il faut vous rendre à la page suivante : http://lists.osgeo.org/mailman/listinfo/grass-user La dernière rubrique (unsubscribe) vous permet de vous désinscrire. Vous pouvez visualiser la page en français en sélectionnant la langue dans la liste déroulante en haut à droite. Cordialement, VB Le jeudi 26 mai 2011 à 20:36 +0100, LUCKHAUPT DANIEL a écrit : Bonsoir votre site ne m'interrsse plus, jesuis en France et je ne parle pas anglais. Je vous prierais de ne plus m'adresser vos messages Amicalement ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] Introduction and installing GRASS
Hello GRASS users As I’m new to GRASS and new to this list, allow me to introduce myself. I’m a part-time GIS post-grad student in Aotearoa / New Zealand. GRASS doesn’t seem to be widely used in this country. If there’s anyone from NZ on this list I’d love to hear from them. University courses are based around ARC, although some opensource programmes were used in my last course. One of my main interests in GIS is exploring the potential of GIS for community groups, NGOs and activist groups. This inevitably leads using open source software like GRASS. I’m planning to blog about my experiences, first installing and learning to use GRASS and other opensource and free to use software, and then exploring how these might be useful for community groups. I hope that this record of my experiences might be useful to others starting out using opensource GIS. I’d also be happy to contribute to the GDP - GRASS Documentation Project. My own experiences as someone completely new to GRASS could feed in to the tutorial and help pages. And I could also help with “reading existing doc in order to weed out completely outdated stuff”. But first I need to install GRASS on my laptop. And that’s where I’ve encountered my first problem! I hope someone on this list can help. I’m using a Presario CQ64, which has an Athlon 64 processor (which could be part of the problem). The current OS is Ubuntu 10.10 Maverick Meerkat. I’ve followed the instructions on the Ubuntugis page. According to the Ubuntu Software Centre, GRASS is installed, and files are indeed present on my HD. I just can’t find a way to open the programme! [I should say that I’m also very new to Linux.] I expected there to be a GRASS icon that I click to open it, but can’t find anything like that. Do I have to use command line? Or has something gone wrong? Any help appreciated. Cheers David ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Introduction and installing GRASS
welcome david, What do you mean you can't open the program? You can't run it? Or you can run but you are having trouble setting up the location and mapset? Anyway, I'm not sure Ubuntu Gis will put a item on your menu so what happens if you open a terminal and type grass Do you see anything? cheers Daniel On Thu, May 26, 2011 at 9:20 PM, David Colyer col...@pl.net wrote: Hello GRASS users As I’m new to GRASS and new to this list, allow me to introduce myself. I’m a part-time GIS post-grad student in Aotearoa / New Zealand. GRASS doesn’t seem to be widely used in this country. If there’s anyone from NZ on this list I’d love to hear from them. University courses are based around ARC, although some opensource programmes were used in my last course. One of my main interests in GIS is exploring the potential of GIS for community groups, NGOs and activist groups. This inevitably leads using open source software like GRASS. I’m planning to blog about my experiences, first installing and learning to use GRASS and other opensource and free to use software, and then exploring how these might be useful for community groups. I hope that this record of my experiences might be useful to others starting out using opensource GIS. I’d also be happy to contribute to the GDP - GRASS Documentation Project. My own experiences as someone completely new to GRASS could feed in to the tutorial and help pages. And I could also help with “reading existing doc in order to weed out completely outdated stuff”. But first I need to install GRASS on my laptop. And that’s where I’ve encountered my first problem! I hope someone on this list can help. I’m using a Presario CQ64, which has an Athlon 64 processor (which could be part of the problem). The current OS is Ubuntu 10.10 Maverick Meerkat. I’ve followed the instructions on the Ubuntugis page. According to the Ubuntu Software Centre, GRASS is installed, and files are indeed present on my HD. I just can’t find a way to open the programme! [I should say that I’m also very new to Linux.] I expected there to be a GRASS icon that I click to open it, but can’t find anything like that. Do I have to use command line? Or has something gone wrong? Any help appreciated. Cheers David ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
RE: [GRASS-user] Re: i.atcorr returns all NULL values
Hi Juan,
Can you please give the download link for your images,
Could you also check the output of i.landsat.toar for them and tell if
reflectance ranges are valid/logic.
Thank you,
Yann
From: Juan Benavides Duque [mailto:jbena...@siu.edu]
Sent: Thursday, May 26, 2011 11:38 PM
To: Chemin, Yann (IWMI)
Cc: Markus Metz; Elena Mezzini
Subject: Re: [GRASS-user] Re: i.atcorr returns all NULL values
I tried Yann's code for the i.atcorr on some Landsat TM5 images
It worked very nice for images taken after 1995 but before that still
returns null values when running i.atcorr for bands 1 and 2
I used TM5 scenes from the same location for 1986, 1989, and 1996 and
the first two (1986 and 1989) had the same problem with the null
values...
sorry I can provide a way to fix it but I hope somebody will
juan c
On Tue, May 24, 2011 at 3:49 AM, Chemin, Yann (IWMI)
y.che...@cgiar.org wrote:
Each created visibility map holds only one value r.mapcalc
expression=visibility=${vis_list[$i]} --overwrite so why not just use
this visibility value as input in the parameter file instead of
creating a map where all cells have the same value?
Yes, this is a valid point, the script is designed to (hopefully soon)
encompass raster maps of visibility data (maybe interpolated...), so
this is a placeholder for the next steps.
-Original Message-
From: Markus Metz [mailto:markus.metz.gisw...@googlemail.com]
Sent: Tuesday, May 24, 2011 12:52 PM
To: Chemin, Yann (IWMI)
Cc: grass-user@lists.osgeo.org; Elena Mezzini; Markus Neteler
Subject: Re: [GRASS-user] Re: i.atcorr returns all NULL values
On Mon, May 23, 2011 at 9:36 PM, Markus Neteler nete...@osgeo.org
wrote:
Hi Yann,
On Mon, May 23, 2011 at 5:07 AM, Chemin, Yann (IWMI)
y.che...@cgiar.org wrote:
p192 r030 image of July 2003 of Italy (L5TM) successfully corrected
for band 1 and 2.
The following script works well in GRASS GIS Trunk SVN.
(better send as attachment since a series of line breaks got broken)
...
# For i.atcorr scripting
#-
vis_list=(10 10 8 9.7 15 8 7 10 10 9.7 12 9.7 7 12 12 12 3 15 12 9.7
6 15) vis_len=${#vis_list[*]} echo $vis_len
... this is not clear to me: why so many values and where do they
originate from? Since we have only 6 channels to work with...
Moreover, how can it be possible that visibility is different for
different channels of the same scene? From the documentation it seems
that visibility is related to aerosol concentration at 550nm which can
not possibility be different for different bands of the same scene.
Each created visibility map holds only one value r.mapcalc
expression=visibility=${vis_list[$i]} --overwrite so why not just use
this visibility value as input in the parameter file instead of creating
a map where all cells have the same value?
Markus M
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Re: [GRASS-user] Introduction and installing GRASS
Kia ora David, Fire up a terminal, and type grass, then enter. This is launching Grass, and a GUI will show up. You will then have to specify a path to store your GRASS data, and define a location (ie a coordinate system + a geographic extent) for your first project. One of the great feature of GRASS is to be usable from the terminal and from its graphical interface. Welcome aboard, Pierre (from Palmerston North, NZ) 2011/5/27 David Colyer col...@pl.net: Hello GRASS users As I’m new to GRASS and new to this list, allow me to introduce myself. I’m a part-time GIS post-grad student in Aotearoa / New Zealand. GRASS doesn’t seem to be widely used in this country. If there’s anyone from NZ on this list I’d love to hear from them. University courses are based around ARC, although some opensource programmes were used in my last course. One of my main interests in GIS is exploring the potential of GIS for community groups, NGOs and activist groups. This inevitably leads using open source software like GRASS. I’m planning to blog about my experiences, first installing and learning to use GRASS and other opensource and free to use software, and then exploring how these might be useful for community groups. I hope that this record of my experiences might be useful to others starting out using opensource GIS. I’d also be happy to contribute to the GDP - GRASS Documentation Project. My own experiences as someone completely new to GRASS could feed in to the tutorial and help pages. And I could also help with “reading existing doc in order to weed out completely outdated stuff”. But first I need to install GRASS on my laptop. And that’s where I’ve encountered my first problem! I hope someone on this list can help. I’m using a Presario CQ64, which has an Athlon 64 processor (which could be part of the problem). The current OS is Ubuntu 10.10 Maverick Meerkat. I’ve followed the instructions on the Ubuntugis page. According to the Ubuntu Software Centre, GRASS is installed, and files are indeed present on my HD. I just can’t find a way to open the programme! [I should say that I’m also very new to Linux.] I expected there to be a GRASS icon that I click to open it, but can’t find anything like that. Do I have to use command line? Or has something gone wrong? Any help appreciated. Cheers David ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user -- Scientist Landcare Research, New Zealand ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
