Python bindings for QGIS.

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Missing pyexpat on QGIS 2.0.1: pyuic4 fails

I have encountered a problem when trying to develop a custom plugin for QGIS 2.0.1 (Python 2.7.5 with two additional Python installations on the same machine). When I try to compile the UI file ...
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0answers
8 views

Apply styles to the attribute window

Is there anyway of "hijacking" the attribute window for full control in Python. I would like to apply the map style to the attribute window also. If the geometry is red, the cell background of ...
2
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1answer
154 views

Why does writing large shapefiles crash QGIS?

I'm trying to write large shapefiles with QGIS 2.0 API, using Python, which crashes QGIS. The data is composed of simple two point lines and a data table of five columns. A thousand features or so ...
2
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2answers
136 views

How can I close the identify result dialog programmatically?

I am trying to close the identify result dialog which appeared when I select to identify a feature from the active layer. Does someone know how can I do it?
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1answer
514 views

QGIS 2.0 Python API: Layer vector style loaded from file, marker symbology is respected, labels are not

Im loading a QgsVectorLayer and showing it on map. I load the style i prepared with desktop QGIS 2.0.1 using the layer.loadNamedStyles(path) function in the API and it seems to work, kind of, because ...
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2answers
164 views

Is there a function to select a region of a map for further processing with Python?

I would like to select a map's region in QGIS for further processing with python console. Ideally I would like to select the region with a mouse drag (like Gimp crop function) and then e.g. analyze ...
3
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1answer
242 views

How to apply a color gradient to a shapefile from QGIS console?

Anyone knows how to do a color gradient from the console to a shape file in Qgis (orin Python)? Like the image below.
3
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1answer
46 views

How to store the CHANGES to a map database

I'm looking into providing a map amendment service for a particular map series. The service will help map owners look into the changes made to the operational features of the map, after the map was ...
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0answers
120 views

QgsMapCanvas displays layer only after i resize the window [on hold]

Im medlling with a standalone PyQGis application (based on 2.0.1). I have no problems with the setup, however when i set up my layers as stated in the docs: layer = QgsVectorLayer(path, name, ...
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1answer
1k views

How to set PYTHONPATH in OS X to use PyQGIS?

I am trying to use PyQGIS in custom applications. I am on Mac OS X 10.9 with QGIS 2.0.1-Dufour. I know I have to set the the PYTHONPATH environment variable. This is the path to QGIS on OS X: ...
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2answers
321 views

Developing standalone gis applications using pyqgis

I am trying to develop a standalone application using pyqgis but I have no clue on where to start and where to write the code to make it happen so if anyone can provide me a tutorial to getting ...
2
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1answer
170 views

How do I access QGIS program settings programmatically?

I am trying to temporarily enable the option in QGIS using PyQt4 to suppress the attribute dialog popup after a feature is added. I found an example in the cookbook but it doesn't indicate how to get ...
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0answers
145 views

Display plugin icon

I'm unable to setup the display of the toolbar icon for a plugin in QGIS 2.0. I have compiled the "resources.qrc" with the correct path and filename, and checked possible spelling errors in the code. ...
3
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1answer
591 views

How to generate a grid programmatically in Python without GUI?

Is there a QGIS Python binding for generating a grid programmatically without using the GUI?
2
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1answer
146 views

How to show in a custom QGIS form the feature and/or geometry info?

I need to show point coordinates on the from dialog used to edit the attributes of a point.. I see that in the formOpen the dialog receives a layerId and a featureId, but no iface object, so how can ...
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1answer
96 views

Irrational feature ID behavior in a PyQgis script

I've written a script to determine the coordinates of a point shapefile and insert them into its attribute table. It works perfectly when the ID sequence of the indiviual features begins with 0, yet ...
2
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1answer
133 views

Workflow Scripting in QGIS

I have created a hexagonal grid shapefile using MMQGIS and want to use this for hexagonal binning. I have another point shapefile which contains patient records for three different types of hospital ...
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0answers
205 views

Calculating area with python qgis

I am a little stumped with determining the area of polygons in the python console. I want the output to be in meters^2, so using: qgis.utils.iface.mapCanvas().setMapUnits(0) ...
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3answers
169 views

How to Project a point on feature in PyQgis?

In Arcgis IProximityOperator.QueryNearestPoint Method was available to get the nearest point. Similarly Is there any function available in pyQgis? Thanks in Advance.
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0answers
86 views

Is there a way to build topology and work with topology relations in PyQGIS?

Is there a way to build topology and work with topology relations in PyQGIS? I'm asking because I need to run some custom generalization algorithms on my data, and I need to preserve topology. ...
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3answers
290 views

How to access user credentials in database connection?

I am trying to automate a couple of things when a QGIS plugin is activated: If Layer A is not in the TOC, add it. This requests username and password to access a PostGIS table using the inbuilt ...
2
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1answer
197 views

Which data providers support loading attribute tables without geometry?

I have a table in Memory from a cx_Oracle query (a list of rows, and a list of field names and their types) in my python plugin and I want to load it as a geometry-less layer (Attribute table) in ...
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0answers
153 views

Unable to render layers in MapCanvas using PyQGIS/PyQt4

I am trying to get some layers into a MapCanvas and style them. I am following the PyQgis Cookbook info here but my code is just not working. I've been spinning my wheels on this for over a week now ...
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1answer
320 views

Unable to load PostGIS vector layer into QGIS using python cookbook recipe

I'm having trouble loading a PostGIS layer using Dufour (from osgeo4w), using the guide at http://www.qgis.org/en/docs/pyqgis_developer_cookbook/loadlayer.html. I just get the 'invalid layer' message. ...
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0answers
84 views

How can I change the NoData value in QGIS 2.x using the python console

I'm trying to add a NoData value to a single band raster image in QGIS 2.0 using the python console but can't find the right bit of code to do it. Here's what I see on the console: >>> ...
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1answer
384 views

How to label vector features programmatically?

I am using python for QGIS 2.0.1 and I have a vector layer of points representing the positions of state labels. I want to display the 'state abbreviation' attribute on the corresponding point for ...
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2answers
639 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 ...
5
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2answers
1k views

Standalone applications using QGIS and environment variables

I've tried going through IRC to see if people can help me out with this, but the medium seems a little clumsy for making any answers clear, so I'm going to try this instead. I would like to program a ...
4
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2answers
439 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 ...
10
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1answer
379 views

PyQGIS file lock release

I was wondering what triggers the release of file locks in pyQGIS? I am trying to delete a few data sources (used temporarily) by calling QgsVectorFileWriter.deleteShapeFile, but I have to quit QGIS ...
2
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1answer
299 views

How to create a symbol with graduated marker size and line width in pyQGIS?

I am using QGIS + pyQGIS + Python. Layer geometry is line. Each line has a magnitude and a direction (from 1st node to 2nd node). What exactly I want to perform is "graduated width marker symbology ...
0
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1answer
430 views

How to zoom to the extent of Qgsvectolayer qgis?

Anyone know how to zoom to the extent of a Vectorlayer in qgis using python plugin?
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153 views

how can i read an attribute value from qgsfeature?

How can i read an attribute value from qgsfeature ? i am trying to update some attribute using other and i have to read value from attribute in the qgsfeature . my source code: provider = ...
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1answer
508 views

How to activate a layer in QGIS layers legend

How can I activate a layer in qgis map legend automatically using python code . I am using qgis.utils.iface.setActiveLayer(self.theLayerToEdit) but the layer is still not checked in the maplegend. ...
2
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2answers
451 views

How to load memory output from QGIS processing?

Many processing algorithms have an option to save output as memory. If ran from toolbox, this works fine, because you can tick the "Open output file after running algorithm" box. Looking at the ...
4
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2answers
922 views

How to get field names in pyqgis 2.0

I am trying to change an plugin from QGIS 1.8 to 2.0. In the 1.8 version I create a table of the field names like this: layer = vlayer provider = layer.dataProvider() feat = QGSFeatrue() allAttrs = ...
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1answer
121 views

Different output from running algorithm in toolbox and from script

I am unable to get the same results when running the qgis:reproject tool from QGIS processing toolbox (QGIS version 2.0.1) as when running it from a Python script (console). In this example I am ...
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2answers
187 views

No prj file output from qgis:reproject

I'm trying to reproject a vector layer using the 'qgis:reproject' algorithm in the processing/sextante module of QGIS, from Python. This kind of works, but the .prj and .qpj files created after ...
3
votes
1answer
732 views

Using in-memory vector layer with QGIS processing / SEXTANTE

I'm trying to run the qgis:clip algorithm from console, but am getting an error when using an in-memory layer as the overlay parameter. Is this to be expected, or am I doing something wrong? Code: ...
1
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1answer
296 views

Select by SQL in QGIS Python

In the GUI there is the Query Builder, but that does not seem to be easily available in Python. The processing (SEXTANTE) module has the qgis:selectbyattribute algorithm, but that only supports ...
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0answers
75 views

PyQGIS - Converting WKB to String

Using PyQGIS, i'd like to print the string representation of a point WKB (like what PostGIS displays in geometry columns). For example: p = QgsGeometry.fromPoint(QgsPoint(2, 4)) wkb = p.asWkb() print ...
4
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0answers
60 views

Using QGIS plugins from Python [duplicate]

Is there a simple way to automate calls to QGIS plugins from a QGIS Python script? Either from console or a plugin? I am ideally looking for a way to specify input/output parameters and bypass GUI. ...
2
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1answer
298 views

pyQgis in stand alone script, vector loading error

I am trying to use the Qgis functions in a stand alone Python script. I m running Mountain Lion OS, 2.7 Python & the Qgis 2.0.1 Dufour. My main problem is that I cannot get started - I cannot ...
3
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1answer
179 views

How to set and configure a value relation edittype in QGIS 2.0?

I am trying to set the edit type of a vector layer to use a value relation. The Python commands below are processed without errors or warnings, but the when I check the properties in QGIS, only the ...
2
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2answers
104 views

Get Index for a group QGIS Python

I am trying to add new layers into a specific group which I can get to work if I know the index but how can I get python to fid the index of a group so it can load the new layer into the group ...
3
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2answers
1k views

how to for loop a folder to batch clip rasters by polygon using python and QGIS

I am using python and QGIS 2.0. I am trying to clip rasters in a folder by one polygon feature. It's the first time for me using (let's say) "PyQGIS", I was used to arcpy before. Anyway, I don't get ...
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1answer
146 views

Setting the PyQGIS Maptool

I apologize if this question was already answered, but I found a lot of examples on how to set the QGIS maptool in a application from scratch, but not inside QGIS (in a plugin). In the examples I ...
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0answers
59 views

How to calculate an expression for a field using PyQgis?

I'm beginner user of PyQGIS. I would like to create one button to calculate one expression for example the relative frequencies for each field. How can i do it? Thanks for your help. Best regards. ...
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0answers
255 views

Unable to use pyQGiS in a custom application - import arcgis.core error

I'm using windows 7 and/or 8 64 bit with QGiS 2.01. I'm wanting to us the pyQGiS tools in a custom python application outside of the QGiS environment (i.e by running a python executable located in ...
2
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1answer
459 views

How to create a QGIS action which copies features between layers?

i tried (i never tried before...) to write a simple python code like action in QGIS on my "XXX" vector layer that: open a layer "YYY" copy the selected feature on my "XXX"layer paste the selected ...