Cropping Shapefiles in QGIS?

Question

I need to clip a large and very detailed shapefile in QGIS showing environmental data similar to a temperature map.

Is there something like the very simple crop tool like in Adobe Photoshop where you can drag a rectangle over an area of interest and crop the shapefile to this area only?

I do have an additional shapefile of neighborhoods/districts that I could also use for cropping but I do not know how to specify "extract a shp/kml only within the borders of district X, row xxxxx in the attribute table of districts.shp"

How can I extract the data primitively within a rectangle of choice or per district?

I need smaller pieces from the large map that has been provided by an environmental geo-institute to be implemented into an mobile Application (Android) to view the quite heavy data in a lighter way.

I made some screenshots of the data and posted them here: http://merglindev.wordpress.com/2012/10/22/extracting-districts-from-big-shapefile-data/.

You can see the districts and the data layers. I need to have every district as a separate file / separately export every dataset per district to KML.

score 36 · Accepted Answer · edited Oct 22 '12 at 16:58

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You say you have a shapefile with appropriate regions, so you can use that for cutting. In the parlance of QGIS, it sounds like you are after Vector->Geoprocessing Tools -> Clip. If you need to assign the data from the input layer to smaller units in the region layer, you could intersect or union instead, in the same menu.

edit (by Kurt): here is an image for clarification: enter image description here yellow: input layer (china) green: clipmask-layer violett: clipped output-layer

edited Oct 22 '12 at 16:58

Kurt

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answered Oct 21 '12 at 22:25

ako

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just make sure, that both layers (original layer and layer, which you use for clipping) use the same projection (crs) – Kurt Oct 21 '12 at 22:45
if i choose input vector layer "my_road_geodata" and use as a intersect layer "districts_2011" it processes a while but i don't see the difference to the original. "Union" just crashed my QGIS :( In the end I would like to export just one district x in combination with the "my_road_geodata" - is there any tutorial out there? – birgit Oct 21 '12 at 22:46
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Are you saying you are clipping a line (road) layer with a polygon layer? And are you after just ONE polygon area for your output, or multiple? – ako Oct 21 '12 at 23:47
It is not a line layer. The "my_road_geodata" shows zones of noise pollution in the form of filled polygons, like in this webapp http://www.si2.nl/eu-kaarten/rdam/ - when cutting it by districts I just want to get the same map but cut in small puzzle pieces... so extracting the areas one by one and saving them in a file like district01 district02 ... would be what I am aiming for – birgit Oct 22 '12 at 08:14
In QGIS 2.16 this it in the Processing Toolbox under QGIS Geoalgorithms > Vector Overlay tools > Clip – chip Aug 24 '16 at 15:25

score 15 · Answer 2 · edited Apr 29 '15 at 16:18

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To create a new clip layer from scratch (In your case the rectangle).

Layer > New > New Shapefile layer (create blank vector object)

In layers menu: Right click on layer > toggle editing > use capture points, capture lines & capture polygons to create your customized new layer.

edited Apr 29 '15 at 16:18

underdark

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answered Apr 29 '15 at 15:12

Matthew Bayly

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score 1 · Answer 3 · answered Nov 16 '19 at 06:07

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See this helpful answer, watch to the very end Custom Clipping in QGIS

answered Nov 16 '19 at 06:07

Martien Lubberink

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Cropping Shapefiles in QGIS?

3 Answers3

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