Python bindings for QGIS.

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5
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0answers
402 views

PyQGIS CRS on the fly reprojetion

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 ...
0
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0answers
63 views

detect signal where delete polygon in qgis?

I am working with QGIS and i want when i delete a polygon and then i commit this action I detect the signal of this operation and use it in python script, I tryed this but dont work: def delete(): ...
4
votes
1answer
361 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 ...
1
vote
1answer
604 views

QGIS python - reference a layer in the table of contents

I'm trying to create a plugin for QGIS using python, But need some help. I want to 1.Zoom to a layer and 2. make the layer visible(switch off or on). But I have managed to zoom to an active layer by ...
3
votes
1answer
328 views

How to add a layer group using pyQGIS?

Good morning, I would like to know how I can create a new group in the layer manager using python code, someone could help me?
1
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1answer
231 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 ...
2
votes
1answer
707 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): ...
0
votes
1answer
569 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
votes
1answer
181 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 ...
0
votes
1answer
81 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 ???
3
votes
1answer
679 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
votes
1answer
230 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 - ...
1
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0answers
224 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 ...
0
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0answers
125 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
votes
1answer
409 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 ...
2
votes
1answer
278 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 ...
3
votes
1answer
197 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 ...
1
vote
1answer
275 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 ...
1
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0answers
152 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 ...
0
votes
1answer
441 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 ...
1
vote
1answer
70 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 ...
2
votes
3answers
728 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 ...
4
votes
3answers
755 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 ...
2
votes
1answer
370 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??
2
votes
1answer
197 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
364 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 ...
0
votes
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() ...
0
votes
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 ...
0
votes
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
0
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2answers
527 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 ...
0
votes
1answer
306 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" ...
0
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0answers
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
votes
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
votes
1answer
365 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: ...
1
vote
1answer
691 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 ...
0
votes
2answers
228 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 ...
1
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0answers
168 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 ...
1
vote
1answer
223 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 ...
3
votes
1answer
944 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 ...
11
votes
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 ...
1
vote
1answer
301 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
votes
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 ...
4
votes
2answers
813 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. # ...
9
votes
1answer
733 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
votes
1answer
177 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
votes
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
652 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
votes
1answer
193 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
924 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 ...
2
votes
1answer
421 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 ...