Python bindings for QGIS.

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255 views

Problem with encoding UTF8 chars in Windows with pyQGIS

I have the problem to show characters (äöü) in a utf8 format in Windows. In Linux there is no problem and everything is displayed correctly. I use at the second line: # -*- coding: utf-8 -*- and ...
4
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1answer
766 views

How to zoom to a selected feature with pyQGIS

I want to create a function that selects a feature and zooms to it (similar in QGIS). Therefore there is following function: QgsMapLayerRegistry.instance().addMapLayer(self.vlayer) def zoomTo(self): ...
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1answer
597 views

How to read attributes in pyQGIS and QGIS 1.8 without setSelectedFeature

I add a vector layer to a map with QgsMapLayerRegistry.instance().addMapLayer(self.vlayer) later the attributes are read with def select_all(layer): layer.select([]) ...
2
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1answer
187 views

How to get mean of pixel values within a buffer zone around current mouse position in QGIS

for a qgis 1.8 python plugin I want to query the mean of all pixel values of a raster layer within a defined buffer around the current mouse position, not for an existing point layer. For the buffer ...
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1answer
82 views

How can i detect the number of polygon is drawed in a edit session in QGIS

I am working with qgis 1.8 and i want to know how many polygon drawed in one edit sessions is there any signal emitted with qgis ???
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1answer
716 views

Add attributes to vector layer with pyqgis (QGIS 2.0 API)

i am trying to make a QGIS plugin ready for the new QGIS API in the current development branch (for the upcoming QGIS 2.0 release). ...
2
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1answer
254 views

How to update data from external table in real time?

I have been trying for a long time to connect a external table data[csv] through Excel (for exmaple) with QGis with the objective to each time i change any data in table(for example data location - ...
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0answers
236 views

How to load the default layer style from Postgresql with Python?

I would like to write a python macro that upon opening my QGIS project file will reload the default style for each layer from the postgres 'layer_style' table. I have had a look at the documentation ...
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128 views

QGIS 1.9 problem with setGrayBandName on the QgsRasterLayer

I have installed the developer version of QGIS on my computer in order to do some work with a multiband raster file. The file consists of 30 bands of information, and I need to step through it with a ...
4
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1answer
434 views

How can I create a new layer from the currrent selection?

Is it possible to create a duplicate layer, only displaying the selection from the layer you are duplicating in QuantumGIS? Simular to ArcGIS -> Create Layer from Selected Features. I looked at "How ...
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1answer
291 views

ImportError: No module named qgis.core

I am on Ubuntu 13.04. I get the following error message - Traceback (most recent call last): File "analyse.py", line 1, in <module> from log import shelve File ...
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1answer
204 views

How to create a line layer which connects a point layer to a line layer?

In the map shown below, I have manually created the dummy lines (in green). Using python, and without using PostGIS or sextante, I would like to automate the creation of these dummy links between a ...
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1answer
281 views

Looking for PyQGIS Syntax Examples/Guide

I am a long-time user of arcgis with intermediate experience python scripting for automation of geoprocessing workflows. I am moving towards using QGIS on the regular and I would like to dive into ...
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0answers
155 views

Spatial Filter in Qgis Using Python

Is it possible to create buffer and get intersected features in Qgis using Python? I did in ArcObjects.but i need the same in QGIS also. Dim topo As ITopologicalOperator topo = chkPoint Dim sFc As ...
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1answer
469 views

Getting error in compiling make file for plugin build in qgis 1.8

I am using QGIS 1.8 for building plugin. For developing i am using following ref this link example. where in this step 6 where compile the makefile in OSGeo4W. gives error pyuic4:command not found. I ...
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1answer
71 views

Qgis 1.9 issues with python [closed]

I already installed the version 1.9 of Qgis and when i runned e Script python on i could this error 'NoneType' object has no attribute 'children' however it works fine on qgis 1.8 could someone ...
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3answers
758 views

How to add QGIS Python API Intellisense support in Aptana Studio3/Pydev

I'm developing QGIS plugins using PyDev in Aptana Studio 3 and I would like to know if it's possible to make it aware of the QGIS API and add some "intellisense" functionnalities when programming. For ...
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3answers
806 views

How to find the polygon inside which a point lies?

I have a layer with polygonal features. Each feature has attributes and values. I also have a list of co-ordinates and I would like to know which feature (or polygon) the co-ordinates lie in. Could ...
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2answers
396 views

How to add layer/raster with specific position in the QGIS layer list?

I use addRasterLayer(rast,'Name') but this adds the raster to the top. It is possible to set position when I add raster at once? Is it possible??
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1answer
199 views

How to store attributes of a large shapefile in a list?

I am trying to store the attributes of a shapefile into a list. With following code it works for smaller shapes: addA = [] While provider.nextFeature(feat): attrs = feat.attributeMap() for ...
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0answers
397 views

How to write vector layer to csv file with geometry by PYTHON?

I use Python try to write vector layer file to csv file with this code QgsVectorFileWriter.writeAsVectorFormat(mylayer, r'c:\temp\xyz.csv', "utf-8", None, "CSV") It can export to xyz.csv but only ...
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1answer
91 views

Make many lines in one layer (Python)

I what to create many lines with this code: v_layer = QgsVectorLayer("LineString", "cable", "memory") pr = v_layer.dataProvider() seg = QgsFeature() ...
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2answers
85 views

Python to get ids from shp dont return all records

I have some Python code to get the ids and georeference from a shapefile: canvas = qgis.utils.iface.mapCanvas() allLayers = canvas.layers() nos = QgsFeature() for i in allLayers: if ...
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1answer
102 views

How to convert geometry of SHP to decimals

I try to create a line with two points. These points are obtained in a SHP layer. How can i convert that points to decimals? Thank you
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2answers
555 views

How to display data from a feature?

I want to display data based on the feature currently selected/clicked on. I am following a tutorial from http://www.qgisworkshop.org/html/workshop/plugins_tutorial.html. It initially shows you how ...
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1answer
331 views

How to use expression in QgsVectorlayer label by using python?

how to show the two field values as a label on features. I have done it for a field called "ErrorDescr" with this i need to show another field values. Other field is "MarkerId" ...
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18 views

QGis non blocking notifications with pyqgis [duplicate]

I'm searching for the way to use the new QGis non blocking notification system with the QGis python wrapper. I found informations on this fonctionnality but nothing on how to use this especially with ...
6
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1answer
2k views

How can I programatically create and add features to a memory layer in QGIS 1.9?

I had a working plugin in QGIS 1.8 which read data from an MSAccess database and added it to a series of memory layers. There is some processing involved in the interim so I don't think simply using ...
2
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1answer
380 views

Understanding the QGIS API documentation to write python code

I am not sure how to use the API documentation to code in Python. For example, I want to determine whether a layer is a point, line or polygon layer and found the following in the API documentation: ...
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1answer
739 views

How to set Marker Line symbol for QgsVectorLayer by using Python?

QgsVectorLayer Right click->Properties->Style->Single symbol->click on simple line in tree node ->symbol layer type -> Marker line Kindly help me to set marker line symbol programmatically by using ...
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2answers
230 views

How to make line with arrow head in QgsVectorLayer using python?

I need to draw line with arrow head or after drawn the line i need to make it as arrow head line by using python. or can we set any arrow head symbol for line features by using python? Kindly help me ...
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0answers
170 views

qgis python app how to add edit feature button?

I'd like to develop a QGIS Python app for plotting points and editing the attributes. I've started with the tutorials here: http://blog.qgis.org/?q=node/59 and read the cookbook ...
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1answer
230 views

open QGIS project with parameters

I am looking at a piece of work to deploy QGIS as the standard within an organisation. There is an existing piece of software that I need to link to QGIS so that when a button is pressed within the ...
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1answer
998 views

How to find the nearest line to a point in QGIS? [duplicate]

My question is that given a point and few lines, how should I go about finding the nearest line to the point? I am aware of How to I find the nearest line to a point?, but that isin ArcGIS and ...
12
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1answer
1k views

How to draw perpendicular lines in QGIS?

I have a situation like this: What I need to do is to connect each point to every line that is at most, let's say 200 m, away from the point. In other words, I need to draw a perpendicular line ...
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1answer
323 views

How to “Merge Selected Features” with python?

I have been looking for the answer to this question for some time now, but can't seem to find it! My problem is straight forward: I have one layer It contains lots of features (only polygons), say ...
2
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2answers
1k views

Creating QGIS layers in python console vs stand-alone application

I am having trouble creating a QGIS vector layer in a stand-alone python script while exactly the same code works fine in python console inside QGIS. The following code results in a proper ...
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2answers
844 views

How to automatically reloaded raster layer if source is changed in QGIS?

How to automatically reloaded raster layer if source is changed? (The path is the same but inside source file are changes) I use: qgis.utils.iface.mapCanvas().refresh() but layer not refresh. # ...
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1answer
787 views

Is it possible to show our custom message in QGIS Status bar using python?

Is there any way to show our custom message in Qgis Status bar using python? Just like in arcgis "IApplication.statusbar.message(0) = "Please wait..." like that is there any option to show ...
2
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1answer
180 views

How to get a message when the map is moved in QGIS?

I want to get a message when every time I move the map. I had: def info(self): QMessageBox.information( self, self.tr( "Info" ), self.tr("info") ) I suppose that used to be something like ...
7
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4answers
2k views

How to get features based on their attributes using Python?

How to Get features by their attributes (similar to Iqueryfilter in arcobjects) in Qgis using python? Instead of getting all features and filter it manually, is there any option to use whereclause to ...
3
votes
1answer
690 views

Joining table to shapefile with pyQGIS

Joining shapefiles is a relatively straightforward proess in QGIS using 'add vector join' in the layer properties menu. I can add a csv file as a vector layer, as well as a shapefile, and join the two ...
3
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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
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1answer
974 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
456 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
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1answer
287 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 ...
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2answers
225 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.
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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 ...
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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: ...