Software plugins that add functionality to the QGIS package

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25
votes
1answer
19k views

How to install a QGIS plugin when offline?

Due to various IT policies at my workplace, QGIS is installed on a machine that is not connected to the internet. I wish to install a couple of QGIS plugins on this system. I have downloaded the ...
11
votes
2answers
6k views

How to check Topology in QGIS?

I have two Shapefiles with Polygons ( City and Forerst) Is there a Plugin who is able check the topology (QGIS)? Like "Knots do not overlap" or something like that? I dont want that they overlap. ...
12
votes
3answers
4k views

How to programatically check for a mouse click in QGIS

I want to know how to check for a mouse click in QGIS. I am trying to write a python plugin and want to provide functionality similar to the "Select Single Feature" tool that already exists in QGIS. ...
15
votes
3answers
4k views

Visual Impact Assessment in QGIS or GRASS

Is it possible using QGIS or GRASS to perform a Zone of Visual Impact assessment? E.g. where can a 100m high structure be seen at a viewing height of 1.8m within 30km, taking into account elevation ...
11
votes
1answer
1k views

Is there a way to access QGIS plugins in Python?

Is there a way to access QGIS plugins in Python? I'd like to write a script to do some geoprocessing, and I'd like to use the clip, regular points and convex hull tools in fTools, as well as the Road ...
3
votes
2answers
2k 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 ...
4
votes
1answer
278 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?
4
votes
1answer
1k 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) ...
8
votes
3answers
7k views

How to access QGIS Plugin Repositories from behind a proxy?

I have been trying to teach myself QGIS by using this forum and others to help. Most of my questions can be answered by downloading plugins that are available through 3rd party repositories but for ...
3
votes
2answers
1k 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
3answers
6k 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 ...
2
votes
1answer
2k views

Opening Esri Personal Geodatabase (*.mdb) using QGIS 2.6?

Is it possible to open an Esri Personal Geodatabase (*.mdb; ArcGIS 10.2) in QGIS 2.6? Previous versions were right.
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
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 ...
5
votes
1answer
780 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 ...
3
votes
2answers
1k views

Programmatically load composer from template and generate atlas using pyQgis

I Am trying to build a plugin to load a print composer from file, generate an atlas and export to image. So far I have been successful in loading the template and exporting it to image. I have been ...
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 ...
1
vote
1answer
208 views

What is the purpose of some functions and files in QGIS Python plugins?

I'm just trying to understand the architecture of a QGIS Plugin created with the QGIS Plugin Builder, as well as the workflow and the linkage among generated files. If possible, I'd prefer a diagram. ...
8
votes
2answers
2k views

Where has the cartogram plugin for QGIS gone?

This plugin used to be downloadable from Carson Farmer's plugin repository page. However, the repository is broken. An old version of the plugin source code is still available at ...
3
votes
3answers
1k 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 ...
2
votes
4answers
3k views

Qgis: How to display special characters German “ÄÜÖß” in a Map?

I have a shape file with names for Regions. These don't seem to contain special characters but ugly hyroglyphes. What can I do do display them correctly. If I import the shape as UTF-8 it doesn't ...
5
votes
3answers
1k 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.
0
votes
3answers
360 views

Georeferencing window won't open QGIS 2.4

I had the georeferencer window open in QGIS 2.4 while project was running, I accidentally closed the Qgs document with the georeferencing window open (worked absolutely fine till then). When I opened ...
4
votes
2answers
3k views

Generate random points in selected areas for

I think my question is answered in different posts but I can't really make sense of them. Background: We are designing a survey of a sample population of farmers to identify the seeds they use. I ...
5
votes
3answers
296 views

Alternative to OpenLayers plugin for QGIS?

Are there any alternatives to OpenLayers plugin to have Google / Bing maps for QGIS projects? I need an high quality cartography (both aerial and street view) but OpenLayer plugin do not allow to ...
12
votes
3answers
4k views

Is there a way to use “Select by Attribute” in QGIS using a python command?

is there a way to use the function "Select by Attribute" in QGIS using a python command? In my plugin the user should enter a value via a GUI and this value should be used in a function which selects ...
4
votes
1answer
4k views

What's the proper format for WKT linestrings when importing into QGIS?

I'm trying to run the following test CSV through the Delimited Text plugin as WKT data: oid,Line 1,LINESTRING((45.554194 -122.686101, 45.433001 -122.762632)) 2,LINESTRING((45.432505 -122.598327, ...
3
votes
2answers
969 views

How to debug 'Layer is not valid error' from Python plugin?

I'm trying to understand what goes wrong with a QGIS python plugin. Basically I'm trying to render a series of POINT. The query works fine, at least giving it by hand from inside PostGIS DB: "SELECT ...
2
votes
1answer
84 views

Getting values from Qt widgets and using them for a buffer

I am writing a simple plugin that finds buffer. My gui has 2 combo box and 1 Line edit. The first combo box will have a drop down of values from column 'States' and 2nd combo will have a drop down of ...
1
vote
1answer
284 views

QGIS Linear Referencing

I'm not sure how to ask this. Essentially; I work for a survey company doing gas lines GIS. We use QGIS. We create hand drawn sketches of pipelines containing all sorts of information including: ...
6
votes
1answer
2k views

How to remove a vector QgsVectorLayer from QGis python plugin

I managed to add QgsVectorLayer in QGIS through a python plugin, for example: vl = self.iface.addVectorLayer(uri.uri(), layerName, self.dbConn.getProviderName()) But how can I remove it?
5
votes
2answers
577 views

How to filter the MouseWheel event in a QGIS C++ plugin?

I’m developing a C++ plugin for Qgis and I want to filter/override the mouse-wheel event. I created a “maptool” to select a polygon feature on a vector layer, the feature has two attributes : an id ...
4
votes
2answers
744 views

How do I set layer transparency in QGIS 2.0 with Python?

I have a raster layer loaded in QGIS and I'd like to be able to set its transparency via the Python console. I'm new to the API and have not been able to find out how to do this. Any help would be ...
3
votes
2answers
551 views

”No module named ogr” when installing QGIS plugins

In QGIS 2.6.1, when I try to install the FlowMapper and QGIS Cloud plugins, I get an error - "The plugin is broken. Python said: no module named ogr" - giving me the only option of removing them. ...
3
votes
2answers
959 views

QGIS 2.0 Plugins missing [duplicate]

At the risk of a series of downvotes but I have just installed QGIS 2.0 after using 1.7.4 and 1.8 previous. It looks great but there are a lot of plugins missing. I understand from the install that ...
3
votes
3answers
491 views

How to install the QGIS Statist plugin in Mac OS X?

I'm trying to install the Statist plugin. I'm running MacOSX 10.7.5. with Python 2.7.3. and Numpy 1.5.1. I have also installed matplotlib 1.1.0 (for python 2.7). When I try to install the Statist ...
3
votes
2answers
798 views

How to connect a PyQGIS plugin with Postgres?

I have some questions for you: I created a python-plugin in QGIS, then I created a Qt gui fom my plugin and at last I created a Postgres DB now I need to make a connection between Qt-gui and ...
2
votes
1answer
461 views

QGIS 2.6 - Point Sampling Tool plugin producing empty shapefile

I use a DEM file (*.tif) and a points layer. My need is basic : getting the Z value for each point by extracting them from the DEM. Both layers correctly opened with QGIS 2.6. The DEM returns a Z ...
2
votes
2answers
2k views

QGis 2.0.1 mapserver extension missing

I tried to export my Qgis projects to mapserver, using RT mapserver extension, because there is not any other extension in my version of QGis.(QGis 2.0.1 Dufour on ubuntu 12.04 LTS). After installing ...
2
votes
1answer
1k views

Getting polygon shapefile node coordinates and point order

I am trying to get the coordinates of each node of a polygon in QGIS. What I basically did is use the following tools: Vector -> Geometry tools -> Extract nodes Vector -> Geometry tools -> Export ...
2
votes
1answer
781 views

QGis Plugin Licence

I would like to create a plugin using commercial software. Does the QGis licence permit this? Are there any restrictions on the licence I can choose to apply to my plugin?
2
votes
1answer
1k views

Problems with Google layers plugins

I currently use Quantum GIS 1.7.4 at work and I have trouble to open Google layers extension. In fact, when I start QGIS 1.7.4 the following message appears and I cannot use Google layers extension. ...
1
vote
1answer
94 views

How to call default tool in QGIS inside plugin using python script?

I want to create a plugin which can draw irregular polygons in QGIS. For that, I want to call the Select features by freehand default tool inside my plugin. How can I do this within a python script?
1
vote
1answer
187 views

Plugin of Multiple buffers in QGIS

I hope to create a plugin to do multiple buffers in QGIS. This is my script: """/*************************************************************************** izisse_test ...
1
vote
3answers
220 views

What is the math behind rasterization?

I'm taking the first steps in QGIS (version 2.2 Valmiera) and I am having some difficulties in knowing what mathematical criterion that QGIS uses when converting polygons (shapefile) to raster. I'm ...
0
votes
1answer
86 views

Halt QGIS on startup

I have a custom made login form in Python, which launches on QGIS startup. But before the user has a chance to enter the credentials, the program starts normally, bypassing the form. From then on the ...
0
votes
1answer
609 views

GRASS in QGIS not working (windows XP)

I am unable to use GRASS algorithms in QGIS 2.0.1 (on windows xp). I've already configured the GRASS path. The algorithms seems to work correctly (I cannot see errors in the log), however in the end ...
0
votes
1answer
509 views

get wkt from geometry in lat lon format

Using the plane geometry editor plugin in qgis 2.0, WKT representation of a feature is shown. The result is in the lon1 lat1,lon2 lat2 format. e.g. POLYGON((85.43523762804622379 ...
-1
votes
1answer
103 views

why Semi-Automatic Classification plugin installation failled repeatedly?

I successfully downloaded Semi-Automatic Classification plugin installer OSGEO from http://download.osgeo.org/osgeo4w/osgeo4w-setup.exe. But it respond that it couldn't the installation. Again I ...
4
votes
1answer
525 views

Snap points to line and calculate chainage using Open source GIS

I have a line layer (representing a pipeline) and a points layer (representing valves) and I would like to calculate the chainage of the valves along the pipeline. I assume that I would first need ...