QGIS is a user-friendly, cross-platform GIS application licensed under the GNU General Public License.

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10
votes
2answers
2k views

How to get FGDB support in GDAL 1.9 without compiling?

I was hoping that I could use the 'master' (nightly-build) version of QGIS to get fgdb support without compiliing (I'm not a developer and frankly have wasted days of productive time trying to get ...
8
votes
1answer
684 views

Is there a QGIS equivalent of the erase tool in ArcGIS?

Is there a QGIS equivalent of the Erase tool in ArcGIS for Desktop?
8
votes
2answers
907 views

Are there any tools / plugins to develop mapbooks using QGIS?

Are there any tools / plugins to develop mapbooks using QGIS?
4
votes
1answer
192 views

Where to report QGIS and QGIS-Plugin bugs?

I often find bugs in Qgis and its Plugins. I would like to ask about this on the internet but I do not seem to find the proper place to address this issue. Are there any instructions?
3
votes
2answers
1k views

Batch Dissolve Polygons based on Attributes in QGIS or FWTools

I was wondering if anyone can help with batching a dissolve. I have a few hundred polygon shapefiles that I want to dissolve based on an attribute. I would like to do this in QGIS or FWTools. Any ...
12
votes
6answers
7k views

How do I create a shapefile showing footprints of Rasters?

I have around 1,000 satellite images in tiff format, and I want to create a shapefile which will serve as an index to the rasters. This is something similar to a raster catalog, but I do not want to ...
8
votes
2answers
3k 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
7
votes
4answers
5k views

How do I convert a polygon into a point?

I want to convert polygons into points. I know how it's done in ArcGis and I think this may sound trivial but it's a serious issue :/. I'll appreciate any hints :)
7
votes
1answer
8k views

Adding Layerfiles (.lyr) to QGIS?

At college we use ArcGIS Desktop 10, but that does not function on my Mac so I have QGIS there instead. I want to do my exercises with QGIS, but we use .lyr files with ArcGIS Desktop, and they are ...
6
votes
4answers
4k views

Qgis - Is there a way to split a polygon layer with a line layer?

I am drawing administrative regions that have boundaries follow streets in another layer. As these streets are pretty long with many vertices, I don't want to re-trace them. I am looking for a way to ...
6
votes
1answer
3k views

How to write standalone Python scripts using QGIS?

I've been learning how to use the Python Console in QGIS using references from qgisworkshop.org. I'm familiar with writing standalone scripts in ArcGIS and want to learn how to do the same with QGIS. ...
6
votes
1answer
1k views

How to create a style file for QGIS from a plain text file?

Using QGIS 1.7. I have a plain text file, which lists 115 rgb values against a map code for a geological map. Viz.: $ head gsv1Msymbology.txt MAPCODE RED GREEN BLUE Oc 143 255 255 WAT 255 255 255 ...
5
votes
1answer
2k views

Calculating distance to points in QGIS

Is there a way of calculating the distance to the nearest points in QGIS? In ArcGIS there is a function called Euclidean Distance, which can take an input vector or raster, and generate a raster of ...
4
votes
2answers
2k views

How to create multiline labels in QGIS?

How can I apply Multiline label option in the label property.Name field contains a lengthy name. I want to wrap it. How can I do it? please help me. My QGIS version is 1.8
3
votes
1answer
126 views

How to horizontally align irregularly shaped point symbol to vector layer in QGIS?

Fairly new to QGIS and searching a method to graphically align my point symbols in the direction of the vector. The symbol represents a water valve in an irregular shape in close proximity to a vector ...
3
votes
1answer
437 views

Manipulating Azimuthal Equidistant Projections in QGIS

I have a shapefile of world countries that is projected as Azimuthal Equidistant with Chicago, USA as the center. I would like to change the projection such that Edinburgh, UK is the center. One would ...
3
votes
2answers
896 views

Simple automated way to split all lines in layer at vertices using QGIS?

I want to automatically split all lines in a QGIS layer at their vertices (like this). I've done a google search and found this article, which is quite close but the workflow is complicated. Because ...
3
votes
1answer
822 views

Get a pixel value

How can i do this operation: I want to get a pixel value fro the satellite image (Landat, GeoTIFF, 7 bands) using qgis-python. What operators should i use? (for example in qgis's Python Console) ...
3
votes
2answers
2k views

Workflow for creating line features between two coordinate pairs in QGIS

I have a table of stream reaches with xy coordinates for their respective tops and bottoms. I'd like to convert the table to a feature, using the xy coordinates as the endpoints of the line. Any ...
0
votes
1answer
618 views

Create a hyperlink to a pdf file in the attribute table [duplicate]

I want to add a hyperlink to a pdf file into the attribute table of a vector layer. I already read the documentation about evis and the answered questions about this here. It didn't seem difficult, ...
14
votes
1answer
2k views

Can QGIS preserve layers when exporting to PDF?

In ArcMap, when you export data to PDF it preserves the layering within the PDF so that you can turn on/off individual map layers (within the PDF itself). When I export from QGIS to PDF, I don't ...
10
votes
3answers
5k views

How to determine the centroid of polygons?

I have a polygon vector and I want to quickly attain the centroid of this polygon for insertion in a text document. I am working with QGIS. I searched through other questions and although some are ...
10
votes
5answers
2k views

How to identify duplicate attributes in a field?

I have a point shapefile with thousand of points. It has an ID code field that supposed to be unique. Every now and then the data entry clerk wrongly type the id creating duplicates.Right now I'm ...
6
votes
1answer
538 views

Where are the Expression-based Labeling options in QGIS?

I have imported a layer into my map to show the location of towns/cities. However I had to set graduated styling so that only cities over a certain population show. I now want to label the ones that ...
6
votes
2answers
4k views

How to move labels in QGIS?

I'm trying to manually move labels but having some trouble. I'm trying to move the labels while in edit mode. I've added fields for x coordinate (all null), y coordinate (all null), rotation (all =0), ...
5
votes
3answers
299 views

How to visually sort the order of Points with QGIS, GDAL, …?

The following Points layer is the basis of a rendering in a Android application. Android allows to draw a shape from the provided points. I cannot use LineStrings. However, the order of points ...
5
votes
1answer
629 views

How do I clip OSM basemap with a polygon?

I've created a map in qgis 2.0. The map uses the OpenLayers plug-in to add the OSM layer as a basemap. I would like to restrict the basemap to be visible only inside a given polygon defined in a ...
5
votes
4answers
3k views

Quantum GIS and ECW images?

How might I enable Quantum GIS to read ECW imagery? At the moment I'm mostly concerned about this on Ubuntu 10.4 amd64, but I also use WinXP & Win7.
4
votes
4answers
16k views

How to fix Runtime Error R6034: An application has made an attempt to load th C runtime library incorrectly?

I just downloaded QGIS 2.0 and everytime I open it I get this error message window popping up: Does anyone know what this means or how I might be able to fix it? Thanks!
4
votes
2answers
747 views

How to automatically reloaded raster layer if source is changed in QGIS?

How to automatically reloaded raster layer if source is changed? (The path is the same but inside source file are changes) I use: qgis.utils.iface.mapCanvas().refresh() but layer not refresh. # ...
4
votes
2answers
373 views

Setting rendering order of line layers in QGIS

I have a dataset where different road types are in separate layers, i.e. motorways, primary roads and secondary roads. In turn, each layer is subdivided by embedded codes into different sub-types - 4 ...
3
votes
1answer
368 views

Cannot see OpenLayers under Plugin in QGIS 2.4

Although I have installed the OpenLayers plugin, I cannot see it in the list when I click on Plugins. Does anyone else have this issue?
3
votes
1answer
1k views

QGIS 2.0.1 Runtime error and crash at Add Delimited Text Layer plugin

I just installed Dufour on my Windows 7 Lenovo ThinkCentre desktop. When I open 2.0.1 I get this error window: And when I try to add the 'Add Delimited Text Layer' plugin I get this message: ...
3
votes
2answers
990 views

How to install shapely for python 2.6 (Mac) NOT 2.7?

I'm trying to use Polygonizer plugin inside QGIS, but it needs Shapely to work. I've installed Shapely (pip install Shapely) but that's for python 2.7. QGIS works with python 2.6 (on Snow Leopard) and ...
3
votes
2answers
3k views

Why does QGIS scalebar show a wrong scale?

I'm using QGIS 1.7.1 and have added a scalebar. The scalebar usually displays in degrees, unless I switch the map's projection to meters, in which case the units are display in cm. This is not ...
2
votes
1answer
262 views

QGIS says “osgeo [python-gdal]” isn't installed on Mac

I know similar questions have been asked (like this one) -- but I'm encountering a unique problem. I installed GDAL complete 1.11 from KyngChaos, but when I open QGIS, I get the following error ...
2
votes
2answers
1k views

Problems with scale bar units in qgis composer

I apologize in advance for again bringing the topic up, I've searched for answers in other posts but couldn't find anything helpful. I fight a personal little war with the scale bar of the QGIS ...
1
vote
1answer
341 views

How to produce multiple maps with same layout for different layers' extents?

I have an area which is divided into several zones the borders of which I have defined as separate layers. The layers are defined by sql queries on a postgis table of line segments joined with a ...
1
vote
1answer
615 views

Delineate polygonal catchment areas from a raster using open-source GIS

I'm 90% sure this basic question has been asked before but looking through the other posts I simply do not see a useful answer. I need to calculate polygonal(vector) catchment areas from a raster ...
35
votes
8answers
12k views

QGIS and gvSIG comparison

Many debutant GIS users are asking me which one is better QGIS or gvSIG. Since I use Qgis and I don't have any experience in gvSIG, I aways say that both are very nice softwares and the chose is a ...
25
votes
2answers
8k views

How to style beautiful road maps with QGIS?

I am trying to design a beautiful map using Qgis. As I'm a software developer not a designer, I was hoping that this will be easy, but it isn't! There is a similar question here Qgis tutorials and ...
25
votes
3answers
30k views

How to add Basemaps from Google or Bing in QGIS?

Like ArcGIS Desktop has the option of using basemaps from ArcGIS online, does QGIS have any such options?
24
votes
3answers
5k views

How to smooth a DEM?

I have a SRTM DEM and I want to create a shaded relief from it. I created the shaded relief in GRASS and the result is very nice, but a little rough becouse the area is near flat and the DEM is 90m in ...
22
votes
5answers
4k views

How to identify clusters in vector point data?

I have a vector dataset of rural broadband data-points (how fast, etc.) and I'd like to explore if there are clusters of points with similar characteristics, and to plot polygons encompassing them. ...
7
votes
2answers
2k views

How to calculate Network Service Areas in QGIS?

Is there any way in QGIS to apply service area buffers e.g if I have a point on a map I wish to show the service coverage of 1 mile, 2 mile, 3 mile, breaks using the road network?
9
votes
1answer
2k views

How to add labels outside of features?

I'm trying to achieve this kind of labeling using QGIS. Apparently, it doesn't seem to be easily supported. Would you have an idea for a workaround ? I managed to have circled text using ...
14
votes
6answers
4k views

A SQL console in QGIS

I know QGIS comes with its field calculator, which is not bad. It also comes with ftools which permits several operations on geometry and attributes. But we often need more control and I haven't seen ...
12
votes
4answers
2k views

How to place elevation numbers on contours with uphill orientation and position?

I want to orient my elevation labels uphill. Is that possible? I'm currently using the labeling tool from QGIS (not that one in layer settings). I want the labels curved and uphill oriented (and I ...
11
votes
4answers
9k views

Feature comparison between QGIS and ArcGIS for Desktop [closed]

I am learning to use QGIS and ArcGIS for Desktop but I cannot find the differences between them. What are the differences between the capabilities of QGIS and ArcGIS for Desktop?
9
votes
1answer
6k views

How to run a simple python script for QGIS from outside (e.g. Sublime Text)?

I would like to run a few small and simple python scripts for QGIS (Mac) from "outside" of QGIS. With outside I mean in this context, either the normal os command line (terminal.app) or even better, ...