Linked Questions

3
votes
0answers
66 views

Extract the outer points of a Point Shape into a Line Shape? [duplicate]

I've installed QGIS 2.8.2 since a few days and have no experience with this application. I try to extract the outer points of a Point Shape into a Line Shape, like a shell for the inner points. All ...
18
votes
2answers
11k views

Is it possible to create Thiessen polygons around nodes in QGIS?

Is it possible to create Thiessen polygons around nodes in QGIS? e.g. http://en.wikipedia.org/wiki/Voronoi_diagram
6
votes
3answers
1k views

Adjusting polygons to boundary and filling holes

Here's the problem: Where: 1: department boundary 3: polygons inside department boundary that "touch" the department boundary(1). They are not necessary fitting well inside 2: holes between 1 and ...
5
votes
1answer
1k views

Growing several concave hulls until they completely fill larger area without overlap using QGIS? [closed]

This is my problem: I have a very large point layer with polling station locations across one country; each point belongs to a specific constituency (900k points, 4k constituencies). I wish to use ...
2
votes
3answers
309 views

Interpolate shape point data with integer data into raster

I have a shapefile I brought into QGIS with a lot of point data. One of the data layers represents an integer value that is assigned to each position. I am attempting to create a raster map of the ...
1
vote
0answers
622 views

How to Create Voronoi Polygon Diagram within surrounding polygon?

I want to create a Voronoi Diagram within an outer polygon. I want to retrieve a result very similar to this solution, which uses ST_DelaunayTriangles() to create Triangles. Actually, it would ...
1
vote
1answer
349 views

Averaging Raster Data

I have 5x5km grid rasters of monthly average wind speed for the UK. I want to convert these into yearly averages, what is the best way of doing so? The only way I'm aware of is to polygonise the 12 ...
2
votes
1answer
389 views

Creating shapefile from polygon points for CartoDB?

I have an Excel file that contains polygon coordinates for different areas. The spreadsheet has three columns: latitude, longitude and area name. Each coordinate makes of a part of the boundary of a ...
1
vote
1answer
337 views

Split multi-geometries polygons

Is there is a way in QGIS (or SQL, ArcMap) to split multi-geometries in polygons automatically. I could do this manually (split features, split multi-part to single-part etc...), but this would just ...
1
vote
1answer
295 views

Creating boundary for multiple point shapefiles that overlay base polygon shapefile?

I have several point .shp files that were geocoded using OpenStreetMap. I located a base map to overlay the point files. I would like to create an artificial boundary based on an 80/20 rule for each ...
2
votes
0answers
65 views

Changing QGIS Symbology

I'm trying to change the symbol from 'marker' to 'fill' in layer properties. Is it possible to change that so I can fill the entire property instead of having points for each property?