Python bindings for QGIS.

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How to set keyboard shortcuts for 'Layers' and 'Browser' panels in QGIS 2.12.1 Lyon?

I have been using the python solution presented in this answer, which has worked well from 2.6 to 2.10 for me, and still works in the LTR 2.8.4. I can't get it to work with 2.12 (and recent point ...
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2answers
113 views

How to create memory layer and populate fields?

Seems like a basic operation using PyQGIS but can't see what I am missing. I want to create a memory layer with the exact same features and attributes from a shapefile. I have looked several posts ...
5
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1answer
180 views

How to replace a shapefile name in a directory using Python QGIS?

How to replace name or delete .shp file from directory using Python QGIS ? import os import processing input = "//input.shp" output = "//output_100.shp" interval = 100 ...
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1answer
170 views

How to use qgis:selectbylocation in PyQGIS?

I am trying to use the processing toolbox to perform a spatial query (points in polygon). I am not sure how to use the tool and I keep getting Error: Wrong number of parameters. Here is my script: ...
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1answer
264 views

Extent problem in PyQgis

I'm trying to set the extent of a square feature to the canvas, that works in QGIS, but when I print the canvas into a PDF, it always gives me some empty area, below is the screenshot of QGIS canvas ...
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1answer
653 views

QGIS Processing Progress

I have been developing a python plugin that uses Processing algorithm for raster calculations. I want to support the gui with progress bar. How can i connect Processing job to progress bar? I found ...
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1answer
460 views

Can I use QGIS plugins in PyQGIS as a stand alone script without iface?

Can I use a qgis plugin especially (openlayers plugin) in stand alone pyqgis script? I don't find examples, just code using iface but that cannot used in stand alone script.
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1k views

clip geometries in postgis table if they are inside a polygon

I have polygons defined in KML files just like this one, which I can easily parse. Example: <Polygon><outerBoundaryIs><LinearRing><coordinates> -91.463940,40.372660,0 ...
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337 views

What's the most efficient way to load feature attributes into a numpy array?

I am currently working on an add-on that relies on the user choosing fields of tables (that can be from shapefiles, csv or dbf) that are open in QGIS and then making computations with such data. ...
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1answer
2k views

How to deploy a QGIS Python Standalone Application with minimum installation size?

I am trying to create a Standalone QGis Application using python. I was able to create the nice looking shapeviewer application by following the steps here. Now I would like to deploy this in ...
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1answer
1k views

How to Create a raster layer from a numpy array using pyqgis?

I am working on a plugin for Qgis to calculate spatial Kernel density maps. I have all the calculations working, all I am missing is a way to turn a Numpy Array, with density values into a multiband ...
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2k views

How to find all intersections and count lines arriving at each intersection?

I'm having a hard time getting off the ground with this, and am trying to move away from ArcGIS / arcpy. I have a shapefile with a network of polylines. I want to find/count all 2-way intersections, ...
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78 views

Batch “Save as” layers w.r.t their geometry type in QGIS?

We have 100's of dgn files. We have successfully "assigned" coordinate system to those dgn files in batch by using "on the fly" + custom CRS. Now we have to save each dgn's geometry (Point, ...
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1answer
313 views

Getting QGIS python modules to work from PyScripter in Windows 10?

Been trying lots of "solutions" from net research but nothing seems to work. I have the current versions of QGIS from OSGEO and PyScripter 2.5 Based on one of the solutions I tried... import sys ...
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1answer
548 views

How change border line to no pen with python console?

From Python console I load a shapefile with qgis.utils.iface.addVectorLayer. How I can remove border lines (change to no pen) in the active layer?
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1answer
3k views

How can I Setup Python to recognize QGIS

I want to use QGIS and work with Python out of the console, but I'm having troubles letting the system recognize the paths of some DLLs. Since I couldn't find a good answer on the web, I wonder if I ...
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1answer
115 views

How to use third-party package in a QGIS plugin?

I'm developing a QGIS plugin and I would like to use arrow or requests packages as I'm used to manipulate dates and REST APIs. QGIS does not come with these packages (at less arrow), so when I try to ...
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1answer
104 views

Create a temporary intermediate layer in a processing script

My algorithm needs a temporary layer in a QGIS processing script. I can use regular pyqgis api to create a temporary layer but want to know if there is a preferred and processing-specific way of doing ...
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374 views

How to open QGIS attribute table in form view using Python?

I've got a plugin where I load some layers. After the last layer loaded, I show the attribute table. However, I would like to select the form view and not the table view (see image). How can I do ...
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2answers
925 views

Load and display a layer from SQL Server using PyQGIS

I'm having a go at using pyqgis from within the QGIS python console to load a layer from SQL Server and display it. I feel like I'm part way there but I'm having a real issue getting the layer to ...
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1answer
784 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 ...
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1answer
639 views

QGis Zonal Statistics Plugin NoData included in Calculations

I have been trying to use the QGIS zonal statistics plugin. My raster has a nodata value of -99999 and all other values are positive. After computing the mean zonal statistics there are a number of ...
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1answer
1k views

How to get pixel size/cell size of raster layer?

After much searching, I've still not been able to figure out how to perform what seems like a simple function: I'd like to get the pixel size/cell size of a raster layer using PyQgis. Is there any ...
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51 views

See python script running while processing a task in QGIS?

Is it possible to see scripts running in Python Console - everything from tools and analysis vector to raster?
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1answer
102 views

Map on canvas renders after image saving

I'm a beginner to Qgis and Python; i need a script (don't need it to be a plugin) to get maps of selected features from a layer satisfying certain conditions; Here is my code: from qgis.gui import * ...
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845 views

PyQGIS CRS on the fly reprojetion [closed]

As a first step of a pyqgis plugin I'm trying to import several shape files at once. To get them aligned, using the GUI, I'd enable on the fly reprojections and set the project crs to WGS84. I'd then ...
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2answers
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) ...
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2answers
2k views

How to install 3rd party python libraries for QGIS on Windows?

How can I use 3rd party libraries on QGIS plugins on Windows? I've developed a plugin that uses rasterio and numpy for a customer, but he's having problems installing rasterio and numpy. Actually ...
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5answers
314 views

Is there any simple integration for counting points in polygon using python qgis?

Is there any simple integration for calculating count of points in polygon using QGIS-Python integration? In other words, are there any pre-defined functions for points in polygon of QGIS using ...
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3answers
1k 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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2answers
2k 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 ...
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89 views

Retrieve available PostGIS connections in PyQGIS

Can I retrieve the available connections to PostGIS databases in PyQGIS? I would like to provide a list of available db-connections, and subsequently a list of tables within the ui of my plugin. I ...
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4k views

How to perform SQL queries and get results from QGIS python console?

I'm writing a python script using QGIS API. I have to get results from postgres database table. The table has geometry field and other non-geometry fields. I want to perform SQL queries on ...
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2answers
3k views

Problem loading vector layer (pyQGIS)

I've installed the qgis on ubuntu 12.04 following the instructions on http://hub.qgis.org/projects/quantum-gis/wiki/Download. I am trying to test the Python API and try to do the follwoing from ...
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3answers
286 views

Change QGIS background colour using python

I would like to change the background colour of a QGIS project using python. I can change the colour using the GUI via the Project Properties dialog: However, I cannot find the equivalent setting ...
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1answer
319 views

Calculate line lengths with Python in QGIS

I found this article which describes the "QGIS GUI way" for calculating the line lengths. http://www.qgistutorials.com/en/docs/calculating_line_lengths.html How can I calculate the length of one line ...
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1answer
625 views

Performing Raster Calculator functions using Python and open source modules?

I would like to perform mathematical functions similar to those you would use Raster Calculator for in ArcMap, however I'd like to do it in Python without using the ArcpPy module. I have the osgeo ...
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1answer
316 views

Set selection color transparent and border color red in QGis using python

I have a layer with different informations. I want to change the selected polygon color to "Transparent". I am able to achieve that using: iface.mapCanvas().setSelectionColor( QColor("Transparent") ) ...
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1answer
906 views

Does mapCanvas().refresh() not work in QGIS 2.6?

Before I used the function qgis.utils.iface.mapCanvas().refresh() to reload the map canvas after for example a layer color was changed from a plugin. But this is not working with QGIS 2.6 for me. ...
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2answers
591 views

Adding a vector layer at QGIS start

I have added a shape file in QGIS using Python plugin. I want to add this shape file when QGIS is loading so i have to add code in the initgui() method. I have used following code in the initgui() ...
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4answers
639 views

How to display a “Save As” dialog for raster files?

I'm writing a QGIS plugin in python. I need to show a "Save as" dialog window in order to allow the user to select the path of the output raster file. Do I need to create a QFileDialog and manually ...
4
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1answer
541 views

How to begin with tool development for GRASS gis or QGIS GRASS

I wanted to begin with customized tool development in Grass GIS or QGIS grass. How should i begin in to develop the tool. I search a lot in google search engine for begin with tool development in ...
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1answer
1k views

Get extents of vector shape features in python

i am just wondering if it is possible to iterate through vector features and return the extent per feature without clipping the vector shape? The code looks like this and comes from the ...
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1answer
101 views

Problem Editing a Vector Layer QGIS

I have a vector layer which I need to load and edit (add several attribute columns). I am doing this without opening QGIS, so within a python script. I have the following piece of code for the layer ...
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2answers
167 views

How to build QgsExpressions in python?

How can I build a feature request expression using variable inside expression? For example values = [1, 2, 3] for j in range( y ): it = vl.getFeatures( QgsFeatureRequest().setFilterExpression ( ...
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2answers
220 views

How to activate a layer by its name in PyQGIS?

I'm writing a script that requires the attributes of different layers to work, and I would like to know how to call a layer that is not the currently active one and get its features. For example, I ...
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1answer
115 views

Select a column like Primary Key in a View from PostGIS using PyQGIS in QGIS

Postgresql doesn't support Primary Key in views. When I load a postGIS view in QGIS "manually", I can choose the column that will be the Primary Key, but I would like to know if I can select a column ...
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2answers
889 views

How to load a raster layer using PyQGIS?

I need to load a raster file from the provided file path. I wish to use it further in the Raster Calculator. I wrote a function which converts string (I assume it is a file path) to a raster object. ...
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1answer
858 views

Select by location in Python

I have a polygon layer and a point layer (with coordinates for each point). The polygon layer got created using the MMQGIS PlugIn (Hexagonal Polygons). I want to select all the points inside each ...
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1answer
414 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 ...