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I would like to complete a point vector's table with Z data. I am not able to take Z coordinate from a dtm
(downloaded from http://www.regione.piemonte.it/geoscaweb/index.php?pgs2=0&pgs3=DTM10&pgs4=DTM10_f&pgs5=.zip&pgs6=%20DTM%20(passo%2010%20m)%20-%20Modello%20altezze%20filtrato%20(fogli%2050.000)&pgs8=50),
I'm using GRASS from QGIS. All files are in its database, correctly imported.

I'm trying with v.what.rast but , even if it tells he succeeds, no new data has been recorded in the point vector's table and no new column appears.

I'm questiong about
1)the possibility of doing that with this particular DTMfile;
2)the fact that there aren't specific requirements for the point vector's table.

  • Here's a blog that I found on the topic pvanb.wordpress.com/2010/02/15/… I must admit to being a little surprised that the operation wasn't a little more straightforward but it seems to work. – WhiteboxDev Oct 16 '14 at 23:37
  • Thanks, I found that the program computed commands, but it didn't update the view of the table (allowing me to see changes) in few time even if I asked it to do it. – Sandra Oct 20 '14 at 6:12
  • So a QGIS issue? – markusN Oct 20 '14 at 10:26
  • Is the table of the vector map in which you are trying to load the values connected to the database? Check with db.tables -p for example. You might need to add a new, empty, column in which the queried raster values will be fed (ie by using v.db.addcolumn). – Nikos Alexandris Feb 25 '15 at 8:18

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