Take the 2-minute tour ×
Geographic Information Systems Stack Exchange is a question and answer site for cartographers, geographers and GIS professionals. It's 100% free, no registration required.

I'm new to desktop GIS, and will try to ask while lacking the proper terms from the GIS lingo:

If QGIS was like Photoshop I would like to make a selection from one layer, and then match that selection to another layer to get the overlap between the two and create a new layer from this overlap.

Formulated in another way:

I want to select all land from each of the Norwegian municipalities. In the shape-file I have (you can download it here: http://www.statkart.no/?module=Files;action=File.getFile;ID=41973) municipality borders are found as "N5000_AdministrativGrense" (just the borders) and "N5000_AdministrativFlate" (borders and the land within each municipality). This data (borders and land per municipality) is too administrative - it includes ocean and we have a lot of fjords in Norway. I need the landmass minus ocean.

The landmass is found in the layer "N5000_ArealdekkeFlate" - or so it looks to a novice at least.

So - I want to find the intersection between the landmass (only land, no ocean) and municipality borders and make a new layer that is all municipalities without ocean.

I'm on a mac with QGIS as my installed tool. All tips, pointers and help is much appreciated.

share|improve this question

2 Answers 2

up vote 1 down vote accepted

You can do it with the Vector tools built into the newer versions of QGIS.

I am using 1.8 at the moment, and it has a Vector menu.

Got to: Vector > Geoprocessing Tools > Intersect.

Alternatively, you can probably devise query on the attribute table that will select just the features you want. Once selected you can export that to another layer.

share|improve this answer

If you use the GRASS GIS toolbox within QGIS, then you can do the job with the v.overlay tool. For a quickstarter, see http://grass.osgeo.org/wiki/QGIS_GRASS_Cookbook

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.