Python bindings for QGIS.

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3
votes
1answer
201 views

How to see print commands through Python Script while programming plugin for QGIS?

This might sound like a silly question. Is there a way that from running a custom plugin made for QGIS that a Python Shell can appear along when the plugin is run, like a debug screen. I'm asking ...
5
votes
1answer
979 views

Speed of editing attributes in QGIS from a Python plugin

I'm trying to edit the value of an attribute for each feature in a layer using a QGIS Python plugin. I've found that doing this outside of editing mode is much slower than while editing (even ...
3
votes
1answer
460 views

Python Script that calls the Voronoi Polygons Function?

I've been looking to see if there was a way to call Voronoi Polygons function found in Vector/Geometry Tools, directly from the code but I have not found one. Does this currently exist? Is there a way ...
2
votes
1answer
288 views

How to get CRS of a raster layer in pyqgis?

I have this problem accessing to the coordinate reference system(crs) of a raster layer map. I wonder if such thing is possible? I have used this xml from GDAL open map service to load in a raster ...
2
votes
2answers
228 views

How to determine the coordinates of the corners of the raster layer

How can we determine the coordinates of the corners of the raster layer? The image opens function QgsRasterLayer.
8
votes
1answer
160 views

How to save python session in QGIS?

After running a lot of scripts in QGIS' python console, I have more than 10 dictionaries and lists, and I need these for further analysis. Is there a way to save python session, with all these ...
1
vote
1answer
257 views

How to add MS SQL table using python console?

I have MS SQL Server 2008 R2 database. How to add MS SQL Table using python console in QGIS?
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2answers
188 views

How to handle adding a PostGIS layer in pyQgis without saving password?

I'm writing python plugin and trying to find the right way to add PostGIS layer on the map without storing user password. After adding layer on the map, I strip out the password from uri like this: ...
8
votes
1answer
492 views

How to address the new “Task-Completed” QgsMessageBar in Python?

I am really amazed what huge steps the QGIS development has taken in the last months. The new iconset, the improved Print composer and many more changes to be seen in QGIS 2.0 are really awesome! ...
2
votes
1answer
387 views

How to add one or more points to an existing polyline or polygon?

Using the following code, I make a polyline with two points. vl = QgsVectorLayer("LineString", layerName, "memory") pr = vl.dataProvider() vl.startEditing() fet = QgsFeature() ...
2
votes
1answer
125 views

How to check if two qgsPoints are equal in PyQgis

I have two points: a=QgsGeometry.fromPoint(QgsPoint(227739,908343)) b=QgsGeometry.fromPoint(QgsPoint(227739,908343)) but when I run: a==b it returns False. What am I doing wrong? Update: it ...
1
vote
1answer
138 views

How to save after using fet.setFeatureId in pyQGIS?

By using the following code, I want to change the id of the line when saving the line. But the setFeatureId command, gives a false when doing the commitChanges(). Any idea how to change the id? vl = ...
3
votes
2answers
245 views

How to write an equivalent to MapBasic's CreateLine in pyQGIS?

I know this kind of question has been asked, in part, before - specifically: Seeing QGIS Python Commands and: How is object created as line using createline stored in .tab file? but this is a specific ...
1
vote
1answer
399 views

How to store selected attributes of vector layer using PyQGIS

I'm following this PyQgis workshop: http://www.qgisworkshop.org/html/workshop/python_in_qgis_tutorial2.html#accessing-data-attributes I have a point layer shapefile. I want to be able to retrieve and ...
3
votes
1answer
411 views

How to calculate all paired shortest path using PyQGIS?

The code for shortest path analysis with PyQGIS specifies start and end nodes explicitly: pStart = QgsPoint( -1.37144, 0.543836 ) pStop = QgsPoint( -1.1027, 0.699986 ) ...
1
vote
1answer
373 views

How to get vector feature by mouse location?

I'm writing a photo grouping plugin. My current problem can be broken up into "end goal" and "baby steps", because I think that's what I want. But if there's a way to get to the end by a different ...
1
vote
1answer
1k views

How to change vector attributes values?

I want to change vector attributes values. i could not get the command fet.setAttribute indeed, it is mentionned in http://hub.qgis.org/issues/7223 that: "The QgsFeature instance now must be ...
3
votes
2answers
1k views

PyQgis overwrite shape file and adding layer to Qgis

I am creating a shapefile in python by: driver = ogr.GetDriverByName('ESRI Shapefile') datasource = driver.CreateDataSource('c:/temp/toke2.shp') layer = ...
1
vote
1answer
417 views

How to write a CSV from Python console in QGIS?

I am trying to write out a CSV file from a vector layer made up of points using the python console in QGIS. I've tried the following command: QgsVectorFileWriter.writeAsVectorFormat(layer_Map, Folder ...
2
votes
2answers
175 views

Save a layer for each unique value using Python in QGIS

I have a map, in which each region is defined as an attribute of the map (I can select each region from the attribute table). I am trying to create new layers each one containing only 1 region using ...
2
votes
1answer
1k views

How to evaluate raster calculator expressions from the console?

How can I execute from the console an expression that should be used with the raster calculator? I'm searching for something like this: qgis.someRasterCalcClass.evaluate("boh@1 + boh@2", ...
1
vote
1answer
316 views

How to use QgsOverlayAnalyzer class in pyQGIS?

I am very new to Python scripting in QuantumGIS, so bear with me please. I am trying to use the QgsOverlayAnalyzer class in QuantumGIS (http://www.qgis.org/api/classQgsOverlayAnalyzer.html#details) ...
4
votes
4answers
425 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 ...
5
votes
1answer
970 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 ...
2
votes
1answer
222 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 ...
0
votes
1answer
642 views

How to read the attribute values using pyQgis?

What is the way to get the information contained in the attribute table, say in column 2, row 2 using pyQgis?
1
vote
2answers
798 views

Where exactly are qgis.gui and qgis.core located?

I'm trying to create a standalone qgis app using pyqgis, i'll be deploying it by copying the install folder of qgis and source folder of my app, and so for the testing purposes i copied qgis install ...
4
votes
1answer
285 views

Personal shell launcher for PyQGIS

I have changed a shell launcher found at http://inasafe.linfiniti.com/html/id/developer-docs/platform_windows.html as to fit my wish: setting the system environment variables to be able to use PyQGIS ...
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0answers
59 views

How to delete a point with known coordinates in python?

I was wondering if there is a piece of code that does the opposite that setGeometry does and removes a point if there is one at x and y coordinates?
1
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1answer
82 views

How do you Select an existing vector Layer and Edit it, using python?

I'm developing a small plugin that needs to be able to select a vector layer programatically based on what layer the user has selected. However I'm not sure how to do so. I believe I found the two ...
4
votes
1answer
919 views

QGIS Zoom from python console

What are the commands to apply all types of zoom (full, on selected layer, etc.) in python console? I'm searching both on pyqgis cookbook and API documentantion, but I'm not finding anything ...
2
votes
2answers
1k views

Extract coordinates from vector layer in PyQgis

In Qgis, I have made a polygon, and from that polygon I have made a vector grid via research tools-> vector grid. The grid covers the entire polygon. Now I want to extract these grid points in the ...
4
votes
1answer
207 views

How to auto-start a pyQGIS thread?

having build some (two) minor plugins, it's now time for me to link a few (perl-) applications to qgis. As there is no perl-interface in qgis I thought the best way to link both worlds together is a ...
3
votes
1answer
604 views

Handle add new feature event and/or access feature before commit?

Is it possible with PyQGIS to catch "add new feature" event before commiting changes on the layer? or at least to access new features before commit.
4
votes
1answer
321 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?
1
vote
1answer
140 views

Get feature while editing

I have created my custom form for features editing, using layer.setEditForm("form.ui") and layer.setEditFormInit("init") properties. init method receives dialog, layerId and featId as arguments. ...
3
votes
2answers
197 views

Merging polygons at county level to state level

I have a shapefile that represents counties (admin 2) only, but I need to create a state level (admin 1) polygon file (I'm using QGIS). I will need to sum up (or average) the relevant data at each ...
2
votes
1answer
125 views

How to get a list of all projections that are currently available in QGIS via the PyQGIS-API

i'm building a QGIS-Plugin and i want the user to choose a CRS out of a combobox in which the coordinates he would enter into some textfields are represented, so these can be converted into another ...
1
vote
1answer
128 views

Raster menu does not have any tools in QGIS

in raster menu in QGIS, only raster calculator is available, how to get other tools, like wrap (reproject) please see the image for help. help me to get this.
6
votes
2answers
2k views

How do I use QGIS python console to iterate through simple layer queries and png outputs?

I'm really new to QGIS coding and I'm having a hard time finding (especially) the api classes/functions to carry out actions of the Query Builder window. I'm basically trying to do this: Iterate ...
1
vote
1answer
698 views

How do I copy all feature attributes to a feature in a new layer?

I'm trying to create a new layer in QGIS based on an existing layer. The new features should have all the attributes of the corresponding features in the original layer. I've been trying to use ...
2
votes
1answer
1k views

How to apply a graduated renderer in pyQGIS?

Just trying to run the following code already given in the pyqgis cookbook to create graduated colors symbology (as in example with 2 classes) I define the source info for the shapefile but when I ...
1
vote
1answer
425 views

Why do I get 'KeyError: 0' when using Line Intersection tool?

I'm using Quantum GIS version 1.8.0-Lisboa and trying to create intersection point using Intersection tool. (Vector -> Analysis tools -> Line Intersections ) But when I do that for my shapefile, It ...
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vote
0answers
293 views

DLL problem with PyQGIS

I am having problems with Python Shell importing the module "qgis.core". When I type "import qgis.core" the Shell ("idle.pyw") gives me this error: Traceback (most recent call last): File ...
3
votes
1answer
617 views

Getting dataProvider from vector layer outside QGIS

I'm using PyScripter to explore PyQGIS API because of it's very handy auto-completion function. I've managed to get a handle on a PostGis vector layer by: >>> from qgis.core import * ...
8
votes
1answer
3k views

How do I maintain a resposive GUI using QThread with PyQGIS

I have been developing some batch processing tools as python plugins for QGIS 1.8. I have found that while my tools are running the GUI becomes non-responsive. The general wisdom is that the work ...
5
votes
1answer
2k 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 ...
3
votes
1answer
267 views

Join GPS points obtained from .GPX file in Python Console

Having loaded the .gpx file into a new layer from python console, I'm unable to access the gps points in the attributes table. Essentially, i'm unable to join these points to form a polygon ...
7
votes
1answer
177 views

Unable to load .gpx file from Python Console

I'm trying to create a plugin which will extract the gpx files and load them onto the active layer window in QGIS. While I'm able to load it using the QGIS GUI from Layer>New Vector Layer, I'm not ...
6
votes
1answer
1k views

How to transform a selected multipart feature into singlepart features while editing in QGIS?

There are several questions and respective answers for how to make a multipart features Layer into a singlepart features one using QGIS: How to break a single polygon into multiple polys? How to ...