Python bindings for QGIS.

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3
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1answer
42 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 ...
0
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0answers
97 views

QgsMapCanvas displays layer only after i resize the window

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, ...
0
votes
1answer
732 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: ...
0
votes
2answers
257 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
votes
1answer
131 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 ...
1
vote
0answers
105 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
votes
1answer
367 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
votes
1answer
123 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 ...
1
vote
1answer
91 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 ...
1
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0answers
87 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 ...
0
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0answers
152 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) ...
1
vote
2answers
129 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.
2
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0answers
80 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. ...
1
vote
3answers
233 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
votes
1answer
158 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 ...
0
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0answers
120 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 ...
0
votes
1answer
244 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. ...
1
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0answers
72 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: >>> ...
2
votes
1answer
275 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 ...
1
vote
2answers
364 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 ...
4
votes
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
votes
2answers
346 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
votes
1answer
322 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
votes
1answer
210 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
291 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?
0
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0answers
107 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 = ...
0
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0answers
43 views

What is the action name in qgsinterface for the deselect feature from all the layer tool?

I want to add the deselect feature from all the layer tool in the toolbar when the qgis user start editing a vector layer. anyone know what is the name of this action in qgis api 1.8?
1
vote
1answer
281 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
votes
2answers
377 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 ...
3
votes
2answers
602 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 = ...
0
votes
1answer
102 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 ...
1
vote
2answers
157 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 ...
2
votes
1answer
497 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
vote
1answer
263 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 ...
1
vote
0answers
63 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
votes
0answers
55 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
votes
1answer
241 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
votes
1answer
155 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 ...
0
votes
1answer
64 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 ...
2
votes
2answers
760 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 ...
1
vote
1answer
111 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 ...
1
vote
0answers
53 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. ...
0
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0answers
25 views

How to SUM the fields selected in aqlistwidget using PyQgis?

I'm beginner user of PyQGIS and I'm trying to write my first plugin(API 2.0). In my ui file I created a qcombobox to select a layer, and a qlistwidget to select one or more than one fields (x,y,..). ...
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vote
0answers
199 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
votes
1answer
311 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 ...
4
votes
1answer
394 views

Using the Processing Framework in QGIS 2.0

I am writing a plugin for QGIS 2.0, and I want to use the processing framework to call some functions. When I open the pyhton console inside QGIS, I am able to call it like this: >> import ...
1
vote
1answer
138 views

How can I add a delete button to feature forms?

I have created some formulars in QTDesigner for capturing and manipulating data in QGIS. The data is stored in a postgis-database. It would be helpful to have a delete-button in this formulars to ...
1
vote
0answers
117 views

Different result featureCount() on QgsVectorLayer QGIS 1.8 vs QGIS 2.0?

I use the following code in a layer action: <uri definition etc> sql = 'id = "[% "id" %]"'; uri.setSql(sql); layername = 'TableName [% "id" %]'; vlayer = ...
7
votes
2answers
927 views

Split a feature when intersecting with a feature of another layer using PyQGIS/Python?

I have a buffer layer (green polygon) which I want to split to two polygons whenever it crosses a barrier (blue line). I have been trying to use "splitGeometry" method, but I just can't get it to ...
2
votes
1answer
138 views

How to load a memory layer into map canvas an zoom to it with pyQGIS?

I would like to load a vector memory layer into the map canvas with pyQGIS. Background is, I create a memory buffer layer around point data. While iterating the points I would like to visualize the ...