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

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4
votes
2answers
162 views

Is it possible to edit a layer in QGIS while there is an active query?

I am new to Quantum and I am digitizing polygon layers using the editing features. I would like to apply simple queries ('date > 2012/08/01'), however while the query is active I cannot edit the ...
4
votes
2answers
1k views

How do I split polygons into line segments?

How can I split my polygon file into "segements"? The lines should be broken up like this picture shows:
4
votes
2answers
290 views

Is there a Legend Limiter in QGIS?

Is there in QGIS a function or a plugin that works similar to Legend Limiter in ArcGIS? The attribute I want to show in my legend has many possible values, I want my legend to only show those values ...
3
votes
2answers
980 views

How to find the middle point of a line in QGIS

I am trying to locate the coordinates of the middle point of a line feature in QGIS. I tried searching online but can't seem to find an easy way to do this.
3
votes
3answers
6k views

Calculating the minimum distance between points and polygons in QGIS

I have two vector layers: one point and one polygon and I want to calculate the minimum distance of each point from the polygons (ie the distance from the closest point of the closest polygon). Is ...
2
votes
2answers
4k views

How to add csv file in QGIS 2.0 using Delimited Text Layer Plugin?

I used to import csv files in previous versions of QGIS using the format below, but when I upgraded to QGIS 2.0 the delimited text layer plugin was changed and I can't import the file anymore. The ...
2
votes
3answers
771 views

How to add QGIS Python API Intellisense support in Aptana Studio3/Pydev

I'm developing QGIS plugins using PyDev in Aptana Studio 3 and I would like to know if it's possible to make it aware of the QGIS API and add some "intellisense" functionnalities when programming. For ...
1
vote
1answer
3k views

'Couldn't load PyQGIS' after upgrade to Raring Ringtail?

I upgraded my Ubuntu to Raring Ringtail. After that, when starting QGIS I receive a message: Couldn't load PyQGIS. Python support will be disabled. Traceback (most recent call last): File "", ...
1
vote
3answers
2k views

Using QGIS with a pre-existing installation of Python 3.2 and matching GDAL

I need to have GDAL/OGR working with Python 3.2 because of another dependency. However, I also want to have QGIS for convenience. However, QGIS - FWTools in particular is built against Python 2.5, ...
1
vote
1answer
834 views

psycopg2 error with QGIS 1.5

So I just installed QGIS 1.5 using the windows installer not the osgeo4w one and now any plugins that need access to PostgreSQL databases don't seem to work, they all throw a: "Couldn't import Python ...
14
votes
3answers
2k views

Rubber sheeting in GRASS or QGIS

We are in the process of getting our property boundaries corrected and a side effect of this is that we need to move any assets that have been drawn relative to the property boundaries, so they are ...
7
votes
1answer
2k views

How to delete fields in QGIS?

When is the option to delete field in an attribute table enabled in QGIS? I'm in editing mode and still am not able to delete a field...
5
votes
3answers
8k views

How to Split Features in QGIS?

I am new at using QGIS. How can I simply split features in QGIS? The manual tells to simply draw a line through the polygon you want to split. But it doesn't work. The line disappears when finishing ...
4
votes
2answers
2k views

Installing qgis 2.0 and saga 2.1 on ubuntu 13.04

I have been trying to get this working for a few weeks now. I am trying to install QGIS Dufor (2.0.1) and Saga GIS from the Unstable branch of the UbuntuGIS PPA. When I attempt to do this I get the ...
4
votes
3answers
712 views

no Get More in Plugin Manager in qgis 2 + ubuntu 13.04

After upgrade of qgis 1.8 to qgis 2.0 I couldn't find the choice "Get more" in Plugin Manager and I can't install plugins.
4
votes
1answer
985 views

Why does Google satellite layer change the project CRS?

I have a project and a topomap in WGS84 (EPSG4326). On the fly CRS transformation is activated. I open Google satellite layer from the OpenLayers plugin. The Google layer is WGS84 / Pseudo Mercator ...
4
votes
3answers
1k views

Convert an arbitrary meta-data-free map image into QGIS project

My background: experienced programmer, amateur historian, complete beginner to GIS (so I'm using QGIS). I did learn to use the QGIS georeferencer tool though. The input: suppose I have an image like ...
4
votes
2answers
6k views

How to use Distance Matrix tool in QGIS?

I have a point data set. Now there are cluster of points based on a field. So I take out one such cluster which has points with same field.I want to find distance between all the points in cluster and ...
3
votes
2answers
80 views

CRS reprojection

I am trying to change the CRS of one shapefile that is originally in NAD27 to WGS84 in Qgis 2.6. When I proceed to make the change, I still continue to see the file in UTM coordinates... I've tried to ...
3
votes
2answers
1k views

QGIS GISBASE specify location

I am just a beginner at this QGIS and GRASS and I am using this QGIS 2.0.1 Dufour which throws a error at the startup that "QGIS couldn't find your GRASS installation. Would you like to ...
3
votes
2answers
688 views

keep the same field headers after joining a table to a shape file in QGIS

I noticed that after joining a table to a shape file the headers of each fields in the table used for the join are changed by QGIS and they are attributed to a different name. For instance, i had a ...
3
votes
2answers
417 views

QGIS DB manager Import layer/file tool won't allow me to choose “Append data to table”

I want to append some data to a layer in my PostGIS DB using a shapefile, but when I use the Import layer/file tool in QGIS, it doesn't allow me to choose the append option. Why is this and how do I ...
3
votes
2answers
2k views

How to install the Python module shapely for QGIS use?

I'm using QGIS 1.8.0 on a Mac with OSX 10.6.8 (Snow Leopard). I've installed QGIS including GDAL, GSL, UNIXImageIO, Freetype, and Matplotlib all from www.kyngchaos.com. When installing the plugin ...
3
votes
2answers
1k views

How to calculate the area of rasters in QGIS?

I have been working with some rasters and would like to know how to calculate the area occupied by one element of a raster in Qgis.
3
votes
1answer
812 views

Does anyone have a shapely install for python “dummies” guide?

I have read both questions in regard to installing shapely on a Mac (OS Mountain Lion) and haven't been able to figure it out. I'm not familiar with python syntax and am just trying to get shapely ...
3
votes
1answer
2k views

find polygon corner coordinates

I am trying to get the coordinates of each node of the polygon I create. I would like the attribute table to display the name of the polygon (ex. address) and then the coordinates of the nodes (ex. ...
3
votes
1answer
1k views

How can I save the label style as SLD in QGIS?

In QGIS there are 2 options to style labels. Using the style properties. Using the label in the toolbox When I dbl click layer -> styles -> save as SLD , the style of the label isn't saved in ...
3
votes
3answers
5k views

How to install Python libs for XYtools to read Excel files

I need to use the XYtools plugin to read an Excel file. After choosing the XYtools incon and indicating an Excel file to read in, a message appears "there is a problem with loading a python module ...
3
votes
3answers
2k views

Why is QGIS not launching?

I've got a problem using qGIS. Always when I try to launch the programme with the desktop icon, nothing happens. I also checked the Task Manager and it doesn't show any process running regarding qGIS. ...
3
votes
1answer
2k views

How to draw a cross section in QGIS

Given my enthusiasm for QGIS, does anyone have a simple workflow for drawing cross sections of earth features? My thing is that QGIS is being used to present the plan view, but we have a little ...
3
votes
1answer
2k views

How to install SDA4PP plugin for Kriging in QGIS?

I am trying to do kriging in QGIS. I have loaded the SDA4PP plug in. Almost all of the items in the SDA4PP dropdown menu are not highlighted and are unresponsive when clicked on - including the ...
3
votes
4answers
2k views

When labelling polygons, not all labels are displayed - QGIS 1.7.0

I am trying to create a simple map of Mexico showing the state polygons and their label. The state shapefile is from here, and the specific file is the first one from the top (Áreas Geoestadísticas ...
2
votes
3answers
277 views

QGIS WFS Error - Could not commit changes to layer

I have a PostGIS database being served by Geoserver. I can load the layers I want into QGIS no worries; however whenever I try to edit the layer I get this error message: Could not commit changes to ...
2
votes
2answers
95 views

Is there any way to 'clean' up ASTER v2 DEM data?

I downloaded all the tiles I needed, then plotted them to find that they don't all seem to have the same quality. Basically, you can see all the edges of a lot of the tiles. Is there any way to clean ...
2
votes
0answers
173 views

Problem loading output layer QGIS

Every time I run operations with temporary file output from the graphical modeler, I get the following error message: Oooops! The following output layers could not be open CLIP: ...
2
votes
1answer
382 views

QGIS rounds up the coordinates to six decimals when saving layer changes

I have the problem that when I create a new point (in a point layer) or a new line (in a line layer of course) and I save the changes to the layer (so NOT the project save) then QGIS rounds up the ...
2
votes
1answer
390 views

Flattening JP2 files to single band (i.e. averaging bands)?

I have created thousands of png tiles using ArcGIS and have merged groups of them into large jp2 files for serving via GeoServer. I need to flatten these to a single band so that I can apply a colour ...
2
votes
1answer
2k views

Convert area from square meters to degrees globally

I have a global raster file with 3600x1800 pixels. I don't have any information about the projection used. The raster contains one band with a quantity with the unit "per square meter". How can I ...
2
votes
0answers
819 views

OSGB36 to WGS84 reprojection 'error'

First off, I am a recent convert to QGIS and am greatly impressed with its ease of use and speed compared with the ESRI products with which I am more familiar - my congratulations and thanks to its ...
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
803 views

Qgis server on Ubuntu Server 14.04: Permission denied

I'm trying to install and configure Qgis Server (2.0.1) on a virtual server with ubuntu 14.04, Apache 2.4.7. After trying to install normally, the server gave me 404 error, so I tried to add ...
1
vote
5answers
2k views

Unable to install ECW support on lubuntu 14.04

I try unsuccessfully to install the ECW support (mainly to use ECW file in QGIS 2.2). We attempt to follow and adapt the howto provided by makina-corpus. My first supprise was the repository ...
1
vote
1answer
169 views

pgrouting unexpected output

Thats my ways.shp file. I loaded this to PostgreSQL DB using PostGIS shape file loader. I ran pgr_anlayzeGraph() on it and found it had a lot of isolated segments. Next I ran pgr_nodeNetwork() to ...
1
vote
2answers
456 views

Any QGIS 2.0 updated RPM for Fedora?

I'm very excited about the new release of QGIS (2.0), and would like to install it on my Fedora 18 machine. I couldn't find any relevant RPMs, and the documentation on the QGIS main site for Fedora is ...
1
vote
3answers
911 views

Can I use QGIS with Qt5?

I want to use QGIS with Qt 5.But i don't know the exact relationship between Qt and QGIS.Will there some problems if i use qgis with qt5 or it will not depand on it...
1
vote
1answer
186 views

QGIS Crashes when writing to PDF

8 Lisboa. I have a very large mapper. Formatted to A1 size with a large area and constraints laid across it. Everytime i try to write to pdf it crashes. It is just due to the size of the file. I ...
1
vote
1answer
2k views

Exporting Symbology from ArcGIS for Desktop to Microstation or QGIS?

I am using ArcGIS 10.1 for Desktop and trying to figure out how to export my symbols of elements in ArcGIS to CAD or QGIS readable format. The problem is, that I can export symbology to a Style, or ...
0
votes
1answer
286 views

How to obtain rotation field name defined in the Labels “Data Defined” section in pyqgis?

I'm trying to find how to get with the QGIS Python API the layer field name that contain the rotation angle used by a layer to rotate its labels? I know that I can obtain the field name containing ...
0
votes
2answers
1k views

How to Join Attributes by Location in QGIS 1.8.0

I have a points layer with site attributes and a polygon layer with region attributes. I'd like to join the names of the regions to the point site locations using QGIS 1.8.0., on Windows XP. ...
-3
votes
1answer
411 views

How to extract drainage line network from GRASS GIS and QGIS [closed]

Giving DEM as input is there any way to get drainage network? I am newbie to GRASS and QGIS ,provide any working examples in GRASS GIS and QGIS with procedure.