Python bindings for QGIS.

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Attribute Error: “List” object has no attribute getFeatures

I am developing a plugin that checks for multipart geometry in a layer in qgis 2.6. I am geeting an error list object has no attribute getFeatures. My code snippet is attached below. def run(self): ...
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95 views

MultiLine field-name label referencing

A labeling routing (which is updated often) is being implemented via pyqgis and a QComboBox. The attached code below worked great, that is until needs for narrowed column headers spawned the use of ...
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38 views

Load Oracle Spatial Raster using PyQGIS

Able to connect to Oracle Spatial 11g and print tables with SDO_GEORASTER attribute both in QGIS python console and standalone application.I get below error when loading rasters from oracle Table. ...
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74 views

Load PostGIS or Oracle Spatial Raster Layer using PyQGIS

How do we load Rasters stored in PostgreSQL-PostGIS or Oracle Spatial 11g into QGIS using PyQGIS? I am able to load vector layers from Oracle 11g with below code. What changes are necessary to add ...
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112 views

How to show Python console at QGIS program start

I wonder if there is a way to open the Python console of QGIS 2.6 directly at program launch. There is a possibility to set a shortcut for the Python console, but I can't find such an option for the ...
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196 views

Why script works on my computer but not on another?

The script below works perfectly fine in my computer. But when running the script on another computer, I receive an error: Error: Algorithm not found The computer has similar specifications to ...
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57 views

Using processing using other output (result from another algorithm) as input

I have a problem. I am developing a standalone app in python and I need to use processing algorithms. I was able to use one algorithm without erros but I need to run other processing algorithm which ...
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1answer
65 views

QGIS toolbars source code

I can see the source code of the core QGIS plugins from the repository in github. But is there any repository of source codes for QGIS toolbars also?
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89 views

Custom QGIS 2.6 map tool - mouse click and release issue

I have create a custom map tool for QGIS 2.6, implementing a canvasReleaseEvent and canvasPressEvent. I can't though get the signals to work on one single mouseclick (I have to click twice). My map ...
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52 views

Send signal when attributes modified - QGIS 2.6

For a QGIS 2.6 python plugin, I am trying to send a signal when an attribute value is changed (values for an existing feature are updated or added and the attribute form dialog is accepted). This ...
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59 views

Why use QgsFeatureRequest() when iterating?

I am unclear on why one should use QgsFeatureRequest() when iterating over a file’s features. Let’s say I would like to print out all IDs in my currently active dataset. Now, most examples will ...
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68 views

Start QGIS with virtualenv Python

is there any means of telling QGIS to use a different Python installation than the default, system-wide one? E.g. use some virtualenv Python /myvirtualenv/bin/python instead of /usr/bin/python? ...
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67 views

Efficiently generate Voronoi layers in qgis via Python

The following python commands both appear to function when called in qgis 2.6 to generate Voronoi diagrams: processing.runalg("qgis:voronoipolygons", pointLayer, 1, None) ...
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154 views

Run processing toolbox outside QGIS in standalone app

I am developing a standalone app in Python, using QGIS libraries including processing algorithms. I am developing in Linux environment and I put the libraries in a folder. Also I put the processing ...
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49 views

How to create a text file containing layer names in QGIS?

My QGIS ToC contains layer groups and some layers that do not belong to any group. I would like to create a text file containing the name of those layers that do not belong to any group. Is there an ...
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146 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. ...
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31 views

If statement using QgsRasterCalculator

So in the sequence of my previous question (Can't use Raster Calculator with two different rasters), I am stuck again in my project. With my source rasters, I created 3 different outputs using ...
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QgsRubberBand with holes

I tried to create a QgsRubberBand object with holes, but failed: rb = QgsRubberBand(iface.mapCanvas(),True) geom = QgsGeometry.fromWkt("POLYGON((0 0,4 0,4 3,0 3,0 0),(1 1,3 1,3 2,1 2,1 1))") ...
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41 views

QGIS 2.6 : Programmatically setting key value pairs for ValueMap widget

Using QGIS 2.6 and Python 2.7 on Windows 7, I am trying to programmatically insert key value pairs into a ValueMap widget via a csv file. Issue is that some of the values are properly inserted and ...
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28 views

Error while creating QGIS plugin

I tried developing a python plugin in QGIS2.6 following the instructions in the link http://anitagraser.com/2014/04/26/getting-started-writing-qgis-2-x-plugins/.When I launch the plugin in QGIS after ...
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102 views

Load the raster image which is in TIF format using QGIS API

I am quite new inthe field of GIS. I am interested in is to load the raster image which is in TIF format using QGIS API I have followed the steps given the in the follwing link to load shape file ...
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1answer
67 views

How to select features using an expression with pyqgis?

How can I select features with pyqgis using an expression? I tried to use an QgsExpression but the select method doesn't take it: exp = QgsExpression("'ogc_fid' = 482") cLayer = ...
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65 views

How to zoom to selected feature with QGIS Python Console

I want to select a feature by ID and zoom to it. I tried the following but the canvas doesn't change. Any ideas? canvas = qgis.utils.iface.mapCanvas() cLayer = canvas.currentLayer() cLayer.select(51) ...
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165 views

Is there scripts of QGIS core plugins available anywhere?

Is there anywhere I can see the scripts of the Qgis core plugins.
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63 views

User Interface file compilation using OSGeo4W shell during qgis plugin creation

I am trying to build a plugin in Qgis2.6 using plugin builder. And as a part of the same, I tried compiling the .ui and .qrc file using OSGeo4W shell. It is showing an error during compilation in ...
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183 views

Why the order of imports matters in a standalone PyQGIS processing script?

I've come across a weird issue while running standalone PyQGIS processing scripts. The order of imports in the script affects its normal execution. You can reproduce the problem by opening a Python ...
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44 views

How can I disable logs being created in standalone python script?

When I run the following script in QGIS 2.6.1, it produces a folder called 'processing', which contains a log, in the directory it reads files from. And since the script reads files from several ...
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66 views

How to modify current QGIS canvas from python script?

I want to zoom into the current active QGIS canvas from a standalone python script. I tried the following but it doesn't impact the current QGIS canvas: import qgis.utils canvas = ...
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1answer
82 views

How to get shapefile extent from standalone script?

I am trying to obtain the extent of a polygon in a shapefile. I am running a standalone script which will create a grid based on the extent of the polygon. I have tried 2 methods: one from the ...
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1answer
77 views

How to add a column/feature with PyQGIS 2.x?

I'm using PyQgis 2.2 and I'm creating a plugin. I want to add one feature/column to a shapefile. But I get error.. I've tried to do this as it's shown in Cookbook: if caps & ...
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98 views

Removing a vector layer from QGIS [duplicate]

Considering my program is generating a shapefile that has to be added to the "Layers" tab in QGIS interface. However, once the utility of the layer is completed, I need to remove the layer in the ...
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1answer
89 views

Error writing memory layer to shapefile in QGIS

I have created a memory polygon layer in my QGIS plugin. Then I added a buffer based on a point. I can see the ploygon memory layer in the map canvas and I can save it to a shapefile from the main ...
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136 views

IdentifyFeature() use via PyQGIS?

Intent is to have two variables (QgsVectorLayer and feature.id() within said layer) as input for the Identify feature map tool in Qgis (2.6). Wondering if a feature can be selected programmatically ...
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148 views

How to efficiently access the features returned by QgsSpatialIndex?

The PyQGIS Cookbook explains how to set up the spatial index but it only explains half of its usage: create spatial index — the following code creates an empty index index = QgsSpatialIndex() ...
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1answer
110 views

How to add fields to shapefile from standalone script?

When I run the following script via OSGEO4W64 Shell, I receive the following error when trying to run the qgis:fieldcalculator algorithm: 'NoneType' object has no attribute 'mapCanvas' I read ...
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1answer
220 views

How to get the file name of current style using PyQGIS?

I get the name of the current style file using layer.styleURI(). Then, I change the style file using layer.loadNamedStyle(different_filename). However, when I call layer.styleURI() again, it ...
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70 views

getting a plugin path using Python in QGIS

How to get a plugin path using Python? I tried QgsApplication.pluginPath() I got u'/Applications/QGIS.app/Contents/MacOS/../PlugIns/qgis' But I actually store the plugin in ...
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29 views

How can I include a color legend for my marker colors when i used a QgsCategorizedSymbolRendererV2?

I have this function that sets the marker color to a different RGB value depending on the attribute price level. I would like to also add a color legend showing the marker color with the level of the ...
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1answer
602 views

Problem with import qgis.core when writing a stand-alone PyQGIS script

I am trying to write a stand alone python script in windows 7 that uses qgis.core and various other qgis libraries. I have found an old question on this subject here: How to write standalone Python ...
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26 views

NameError: global name 'QgsDataSourceURI' is not defined

Following on from my previous question I cannot seem to get my function to run using script runner in QGIS. However, if i type then out in the Python Console then they work and load the layer in ...
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396 views

Cannot run standalone QGIS script

I've been trying, along with this post, to run a script in OSGeo4w Shell, outside of QGIS. But I get the following error: ImportError: No module named qgis.core I have also read the following ...
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Searching a table within PostGIS using PyQGIS script

Morning all, I am looking for some guidance in trying to set up a script that will search a PostGIS database using a wildcard and then open a certain file directory that will be in one of the fields. ...
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63 views

Via PyQgis how to refresh a modified CSV layer without having to reopen the file? [duplicate]

UPDATED: With an CSV layer Qgis workspace [loaded as a delimited text layer], an external algorithm is ran; outputting (writing) new values to certain rows in the layers source CSV file. The writing ...
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105 views

Writing a shapefile using OGR, from Shapely Geometry - No feature added Error

I am trying to write a shapefile from a Shapely geometry using PyQGIS in the QGIS 2.6.0 console. Lines of code before the OGR method to write shapefile: extnt = poly.extent() # gives a QtRectangle ...
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46 views

How to change values in a raster file at particular positions?

I have a collection of coordinates which comes from a QGSGeometry object. The shape is a polygon. example: qgsGeometry [[(75.2172,17.6566), (75.8499,17.9613), (75.5218,17.2113), (75.2172,17.4574), ...
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15 views

How to zoom to the features by selecting the feature with the key event

For zooming to the features first i am selecting the feature and then i am zooming but when i am selecting the feature keyevent stoped working. layer.select(feat.id()) ...
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67 views

How to customize the visibility of buttons in QGIS?

The built-in toolbar named "Composer" has an icon "Duplicate Composer". I wish to toggle the visibility of this button in the toolbar. How do I achieve this using pyqgis?
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158 views

Vector -> Geometry Tools -> Extract Nodes equivalent in PyQGIS API

My question is fairly straight-forward. Would anyone know the PyQGIS equivalent of the Extract Nodes tool in QGIS? I don't seem to find it in the API documentation. If you do, kindly share the ...
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224 views

How to use QGIS explode lines with Python

I want to access the explode lines function in Python outside of QGIS from a standalone script. What module do I have to load in order to use it? How can I access processing? from qgis.core import * ...
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How do I step into the C++ functions from an external Python app I'm debugging?

I just wanted to see how to step into the C++ class QgsVectorLayer()'s methods from the python call to QgsVectorLayer(self.uri.uri(),'foo','postgres'). I'm trying to debug and it trying to step into ...