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

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2
votes
1answer
4k views

Import MySQL Spatial vector layer in QGIS

I have a spatial table called 'places' in MySQL, with a spatial column 'pt' (point). I tried to import it in QGIS and no points appear. I created a view 'places_as_text' which reproduces the table but ...
1
vote
2answers
212 views

Problems with plugin/installer manager in QGIS 2.6.1 Debian

An error has occured while executing Python code: Traceback (most recent call last): File "/usr/share/qgis/python/pyplugin_installer/installer_data.py", line 460, in xmlDownloaded if ...
1
vote
1answer
3k views

Clip raster layer with *raster* mask layer in QGIS

Given two input layers 1. The clip layer - an arbitrary layer (though in my case it's a float 1 band geotiff) 2. The mask layer - a paletted raster in which every pixel is either NO DATA or a single ...
1
vote
2answers
2k views

Make a polygon from intersecting lines in QGIS, using Polygonize or similar?

In QGIS, I want to make polygons from a set of intersecting lines. Looking at the screenshot here, I want chop the purple line (it's a closed line, not a polygon) where it crosses the green and blue ...
1
vote
1answer
1k 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 ...
36
votes
8answers
16k 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 ...
36
votes
3answers
52k 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?
25
votes
2answers
10k 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 ...
20
votes
5answers
6k views

Obtaining print quality PDF or PNG output from QGIS?

I work with people who use ArcGIS Desktop and they have found the best resolution output images are made by creating PDFs. They tell me that *.png and the rest out of ArcGIS Desktop are not ...
14
votes
5answers
2k views

Find pseudo nodes in free GIS software

Software gvSIG OA Digital Edition 2010 have tools topology for finding pseudo nodes in linear geometry. I set cluster tolerance 0.00002 and maximum number of errors -10000 for 20000 link count linear ...
23
votes
5answers
6k 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. ...
12
votes
4answers
14k 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?
10
votes
2answers
2k views

How do you display related records in QGIS?

Coming from an esri background I have always used relationship classes in a gdb to display records related to a feature. Eg. Relate 1 survey point to many documents, photos etc. Does any one know how ...
6
votes
2answers
7k views

How to connect to Postgres with QGIS?

Oddly, it should be simple, but I can't connect to a local PostGIS database. My installation is with Mac OS X (10.8), Postgres.app (in doc it's said to have PostGIS included) and Quantum GIS 1.8. ...
5
votes
3answers
4k views

3D visualisation with open source GIS software [closed]

I'm searching for QGIS (or other open source GIS software) tools that can analyse XYZ data. Also I'm interested to hear about if anyone have migrated to non commercial software regarding geological ...
18
votes
5answers
6k 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 ...
8
votes
1answer
7k views

Create a csv with geometry as WKT in QGIS (and choosing the field delimiter)

Is there a way to choose the field delimiter when exporting to CSV with geometry as wkt in QGIS? I have a shapefile with donut holes and I'd like to export it as a CSV. It's for a partner whose DB ...
8
votes
3answers
16k views

How to export Polygons to CSV with coordinates?

I am very new to QGIS, so please bear with me. I have a ".shp" file, which is contains a set of boundaries for suburbs of Australia. I opened it to QGIS and I would like to export it into a CSV file ...
4
votes
1answer
2k views

QGIS on Mavericks

I have been trying to install QGIS on Mavericks and I have failed. Prior to installing QGIS, I installed GDAL using homebrew. I also installed Numpy, SciPy and pyqt using the detailed instructions ...
11
votes
2answers
3k views

Is there a good qml or sld file available for QGIS + Openstreetmap data?

I'm looking for a qml file (or equivalent e.g. sld) to allow me to use QGIS to take Openstreetmap data and produce paper maps. I'm re-asking this question (it was asked once or twice over a couple of ...
11
votes
1answer
3k views

How do I build a custom form for entering attributes in QGIS

I've done this many times in ArcGIS and ArcPad but I don't even know where to start building a custom form for data entry in QGIS. I would like to do this for field operations--QGIS would make a good ...
8
votes
5answers
6k views

How to quickly calculate bounding box coordinates of a selected polygon with qgis

I just manually (and somewhat inaccurately I'm sure) retrieved the bounding box coordinates for a county polygon, which is a selection from a larger layer of county shapes. I'd like to be able to use ...
16
votes
6answers
7k views

Generate points that lie inside polygon

I have polygon feature and want to be able to generate points inside it. I need this for one classification task. Generating random points until one is inside the polygon wouldn't work because it's ...
10
votes
7answers
12k views

How to merge lines with slightly different endpoints in QGIS?

In QGIS, I have two lines. The endpoints are near each other, but not quite aligned. I'd like to turn the two lines into one, with the two endpoints merged into midpoints. The closest I've been able ...
6
votes
4answers
2k views

Is it possible to create 3D dxf with OGR?

Does anyone know if it's possible to create a 3D dxf with OGR. I would like to assign our contour lines a z value and export them to dxf for some cad work. PS I know FME can do this, however I would ...
5
votes
2answers
593 views

Scale and Z factor have no effect on hillshade analysis in QGIS

I used an SRTM DEM to create a hillshade in QGIS 2.2.0. However, the resultant hillshade seems to be vertically exaggerated. Also, changing the settings for scale and z-factor does not have any effect ...
5
votes
4answers
6k views

What is the projection of WGS84 in GIS software?

WGS84 is a reference ellipsoid that determines coordinates of every point on Earth using latitude, longitude and height about the its surface. This ellipsoid is often used as a base to make maps. ...
3
votes
3answers
2k views

How to get shapefile of river from OpenStreetMap?

I dont want to download whole map of an area. I just want rivers and other waterbodies present in an area in shapefiles so that I can use them in Qgis. I tried geofabrik but it is giving whole map and ...
2
votes
5answers
4k views

Is there any way to extract coordinates of a road segment using QGIS?

I add my own road vector data on top of Google map using open layers plugin with QGIS. The vector layer is generated using PostgreSQL DB. Is there any way to extract coordinates of a road segment ?
13
votes
1answer
827 views

How to setup QGIS Master and Stable in parallel on one Linux system?

I mainly use the QGis Master (nightly build) for my Debian Linux and I'm quite happy with it. But for educational and demonstration purposes, I now have to work with the Stable(1.8) version. How can ...
10
votes
1answer
603 views

Can PostGIS and QGIS provide dependable multi-user editing?

After considering a few options, I'm trying to give my 15-20 QGIS 2.2 users the ability to concurrently view/edit one or two basic point PostGIS layers, largest one has just 16,000 records. I've ...
10
votes
1answer
723 views

How to render a table with mixed geometry types in QGIS?

I created a table with geometry type "GEOMETRY" AND inserted data of point, line and polygon type. My question is how to show this spatial data Qgis not supporting for geometry type "GEOMETRY".
10
votes
1answer
4k views

How to display geoJSON from an URL in a layer?

I am looking for some type of plugin or code which would allow me to add a geojson URL, define the areas to input the lat/long variables from the visible Qgis canvas map and call/render the results ...
9
votes
2answers
14k views

How to enable projection transformation in QGIS

My QGIS project has two layers, one layer is retrieved by Google layer plugin which fetches the static Google map image whose CRS is +proj=merc +lon_0=0 +lat_ts=0 +x_0=0 +y_0=0 +a=6378137 +b=6378137 ...
7
votes
2answers
1k views

Is it possible to conduct a flood model analysis with QGIS using a DEM?

Is it possible to conduct a flood model analysis with QGIS using a DEM? Need to simulate rising water levels on a 250k map.
7
votes
4answers
12k views

How do I load a .dbf file into QGIS?

I want to use QGIS to extract lat/lng data from the vertices of polygons. There are about 400 polygons, each with maybe 200 vertices. I am having trouble with step one, getting the data into QGIS. ...
7
votes
4answers
5k views

How to change field length in QGIS

I have a shapefile I made in QGIS 1.7.4. One of the fields is a String of length 80. I'd like to make the field accept longer stings, but I can't figure out how to change its length. How do I do this? ...
6
votes
2answers
2k views

How to use map composer in a stand-alone script?

I'm trying to follow the map rendering section from the pyqgis cookbook, but I'd like to test this as a standalone application. I can do the first part, using simple rendering, but I'm a bit stuck ...
5
votes
1answer
783 views

Is there a purge function to remove layers from a qgs file which are not present in the Layers pane?

I have some QGIS projects that I've been using for long time, adding and removing layers, updating reference to deleted or moved files etc. Opening with a text editor the qgs file I see that it ...
4
votes
4answers
5k views

Measuring the distance between lines and points in QGIS

Using QGIS - I have a vector of fault lines. I have point data in the form of a csv which I have also loaded into QGIS. I need to know how far each point is from the nearest fault line then enter ...
3
votes
1answer
1k views

How to find the nearest line to a point in QGIS? [duplicate]

My question is that given a point and few lines, how should I go about finding the nearest line to the point? I am aware of How to I find the nearest line to a point?, but that isin ArcGIS and ...
2
votes
2answers
2k views

QGIS Server Capabilities Response doesn't contain any Layers

This question is similar as this one QGIS Server not working (problem with fast CGI), but with more details: I installed the latest QGIS from trunk on Linux (Ubuntu 11.04) in the non-default location ...
10
votes
2answers
10k views

Is there a way to manually place labels in QGIS?

Is there a way to manually place labels in QGIS? I have a map which has almost-duplicate labels in some places (e.g. E 1st St and 1st St) and I'd like to remove some of them. Also, I'd like to move ...
9
votes
1answer
721 views

How to address the new “Task-Completed” QgsMessageBar in Python?

I am really amazed what huge steps the QGIS development has taken in the last months. The new iconset, the improved Print composer and many more changes to be seen in QGIS 2.0 are really awesome! ...
8
votes
2answers
3k views

How to correctly install QGIS with plugins and GRASS-integration from source?

I'm running a Sabayon GNU/Linux (based on Gentoo) at my home desktop system and I want to install Quantum-GIS. I'm currently using the qgis-1.7.0-package from the repositories. But this is somehow ...
7
votes
2answers
1k views

Easiest way to create historical street maps using QGIS

I want to make some historical street maps using QGIS. I understand how to upload a historical OS map from DigiMaps to QGIS, but I want to actually 'draw' the streets myself in order to have some ...
7
votes
4answers
2k views

How to close watermarks window in QGIS Openlayers plugin?

I'm using Quantum GIS Ver. 1.7.4. I have upgraded openlayers plugin 0.7 to 0.9. However when I open google satellite, a watermarks/copyright dialog box "Data Peta@2012 ..." appear in the middle of the ...
7
votes
2answers
2k views

Join attributes of point and line layer by location (closest distance) in QGIS

My problem is the following: i have a line shp (target layer) and a point shp (join layer). the second one (point layer) holds an attribute which i want to join with a line layer based on closest ...
7
votes
3answers
6k views

QGIS- How to create an “area of interest” polygon mask

I've created a GP tool using ArcGIS that creates an "area of interest" mask from selected features. Effectively it creates a new donut polygon layer where the hole was the previously selected ...
6
votes
3answers
2k views

How to set up a Coverage Layer for Atlas Plugin?

Has anybody utilized the Atlas plugin? I am starting to take a look and setting it up on a project. My question is how do you set up the layer that is utilized for the coverage layer. Is there a way ...