[GRASS-user] Cross-validation output
Hello everybody, I am using v.surf.rst to interpolate a bathymetry survey. Following the examples on the 3rd Grass Book, I have interpolated the results from the cross-validation procedure to check if there are areas that need a more accurate sampling. Most of the surface is ok, but there is a small area where the difference is very high; you can check it out from this picture: http://www.thebighouse.biz/data_cv.png The issue is that there are bigger zones with no points that show a lower difference value. Why this? Thank you very much for your help. Luca -- View this message in context: http://www.nabble.com/Cross-validation-output-tp18808883p18808883.html Sent from the Grass - Users mailing list archive at Nabble.com. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Compiling addons from svn repository
On 04/08/08 14:52, gianluca massei wrote: Thanks Moritz , great tip! I'm working in a module that implemented ELECTRE algorithm. I've just finisced a module named /r.roughset/ for knowledg discovery with rough set based on rough set library. You can download the source code from grass wiki (http://grass.osgeo.org/wiki/GRASS_AddOns#r.roughset) and I'm happy if sameone caould try it and report me tips or bugs. It would be easier to test if the module description was a bit more elaborate. You should add a description.html with at least a 'Notes' section to explain the module and its parameters. [BTW, you might want to clean up the source tar ball a bit and delete the temporary files it includes, i.e. r.roughset.tmp.html and the ~ files.] Moritz ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Compiling addons from svn repository
I've clean up a little bit r.roughset and I've write some explanation note. In the next weeks I'll improve documentation (and the English !) Thanks Gianluca Moritz Lennert ha scritto: On 04/08/08 14:52, gianluca massei wrote: Thanks Moritz , great tip! I'm working in a module that implemented ELECTRE algorithm. I've just finisced a module named /r.roughset/ for knowledg discovery with rough set based on rough set library. You can download the source code from grass wiki (http://grass.osgeo.org/wiki/GRASS_AddOns#r.roughset) and I'm happy if sameone caould try it and report me tips or bugs. It would be easier to test if the module description was a bit more elaborate. You should add a description.html with at least a 'Notes' section to explain the module and its parameters. [BTW, you might want to clean up the source tar ball a bit and delete the temporary files it includes, i.e. r.roughset.tmp.html and the ~ files.] Moritz Database dei virus interno non c aggiornato. Controllato da AVG - http://www.avg.com Versione: 8.0.138 / Database dei virus: 270.5.10/1584 - Data di rilascio: 31/07/2008 12.00 ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] Seppo Kaitala/FIMR/FI is out of the office.
I will be out of the office starting 04.08.2008 and will not return until 21.08.2008. I will respond to your message when I return. ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] Cross-validation output
Hello Luca, first - double check Your data - are all data points OK. I have seem when in some location are two points with different values (operator error) and thus interpolated surface looks strange. second - generate segment map to see which points affect that strange area and probably consider adding additional data points in bogous area. Sometimes it's clear for human what kind of values one can expect in specific area but interpolation algorithms can't get it right. third - probably You should play around with tension parameter - lover impact distance of single point and thus reduce interpolated surface buckling. Maris. 2008/8/4, Casagrande Luca [EMAIL PROTECTED]: Hello everybody, I am using v.surf.rst to interpolate a bathymetry survey. Following the examples on the 3rd Grass Book, I have interpolated the results from the cross-validation procedure to check if there are areas that need a more accurate sampling. Most of the surface is ok, but there is a small area where the difference is very high; you can check it out from this picture: http://www.thebighouse.biz/data_cv.png The issue is that there are bigger zones with no points that show a lower difference value. Why this? Thank you very much for your help. Luca -- View this message in context: http://www.nabble.com/Cross-validation-output-tp18808883p18808883.html Sent from the Grass - Users mailing list archive at Nabble.com. ___ 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] editing rasters
Hello users! Is there a easier way to edit rasters than d.rast.edit or r.digit? i'm thinking of tools like those you find in common image editing programs like photoshop or gimp (brush, eraser, zoom in, zoom out, etc...); maybe even export a map and edit it with those programs? thank you very much, Juan ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] editing rasters
On Mon, 2008-08-04 at 16:57 -0300, Juan Manuel Barreneche wrote: Hello users! Is there a easier way to edit rasters than d.rast.edit or r.digit? i'm thinking of tools like those you find in common image editing programs like photoshop or gimp (brush, eraser, zoom in, zoom out, etc...); maybe even export a map and edit it with those programs? thank you very much, Juan 1. export your map with r.out.gdal as a geotiff. Be careful with what kind of data you have, how many categories (Byte, Int16, etc.) 2. Open with GIMP and edit BUT DO NOT resize the image, rotate, crop or similar. 3. Save as Tiff with other name than the original GeoTiff # For steps 4,5 look at [1] 4. Export with listgeo the geo-metadata from the original GeoTiff 5. Apply the geo-metadata to the Tiff file with geotifcp Greetings, Nikos [1] http://www.remotesensing.org/geotiff/faq.html#preserve_metadata ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
Re: [GRASS-user] editing rasters
On Mon, 2008-08-04 at 22:51 +0200, Moritz Lennert wrote: On 04/08/08 22:19, Nikos Alexandris wrote: On Mon, 2008-08-04 at 16:57 -0300, Juan Manuel Barreneche wrote: Hello users! Is there a easier way to edit rasters than d.rast.edit or r.digit? i'm thinking of tools like those you find in common image editing programs like photoshop or gimp (brush, eraser, zoom in, zoom out, etc...); maybe even export a map and edit it with those programs? thank you very much, Juan 1. export your map with r.out.gdal as a geotiff. Be careful with what kind of data you have, how many categories (Byte, Int16, etc.) 2. Open with GIMP and edit BUT DO NOT resize the image, rotate, crop or similar. 3. Save as Tiff with other name than the original GeoTiff # For steps 4,5 look at [1] 4. Export with listgeo the geo-metadata from the original GeoTiff 5. Apply the geo-metadata to the Tiff file with geotifcp IIUC, you can also do this with gdal_translate (e.g. with the -mo flag, and the projection setting options). Moritz Maybe this is even better. I suspect that some geo-tags are lost (?). Not sure but I've seen some time ago a few error messages while using listgeo/geotifcp. I will post back if I face a problem (again). Greetings, Nikos ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
[GRASS-user] Compute volume of water using depth vector points.
Dear all, I imported and digitized a hydrographic chart for depth vector points in the ocean and vector lines along the coast enclosing these ocean waters. I am looking to the interpolate these randomly digitized depth points over a grid of any resolution and then later compute the volume of the water in the ocean channel between two land masses. Which modules of GRASS GIS would help me accomplish the above two tasks. Regards Nagesh ___ grass-user mailing list grass-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/grass-user
