3

I have a vector layer of points. Can I get an output from a rasterlayer which contains DTM-values (height) determined by my points placement?

4

@WhiteboxDev mentions two scripts. There is a third which may be best in your situation and that it Point Sampling Tool. This has been available at least since QGIS 1.8 and works very well. You can even sample simultaneously across many rasters and even vector polygons to get all the values from various layers at each point. Load it via Plugins->Manage and Install Plugins.

3

At least on my version of QGIS (which is a bit dated) there are two scripts, one called Extract raster values to CSV and one called Extract raster values to shapefile. I suspect these are what you are looking for but unfortunately there isn't much documentation on either tool provided.

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  • Thanks for the help. I have tried all your methods and the "point sampling tool" was the one working for me. The other methods crashed for me. Either it has to do with my installation or the rastersize combined with cpu-power could be a reason. Although the point sampling tool didn't go all smooth. I have 1268 points + 7 rasterlayers and the algorithm (sampling points) always stopped at 460. Is this a built-in limit? Instead I splitter my points layer into 7 layers and did the exercise 7 times from raster to raster. Any comment on that would be great. – CARTOS Jan 29 '15 at 7:51
2

There are probably better ways, and it would depend on the resolution of your DTM and how much grunt your PC has, but you could use the Polygonizer:

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Then use a spatial join of choice, I like the Join Attributes by Location tool under Vector > Data Management Tools:

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