Python bindings for QGIS.

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How to incorporate QGIS custom widgets into plugin? [duplicate]

Developing a plugin with Qt Designer for QGIS 2.14.1-Essen on Windows 7 and having trouble inserting the QgsCollapsibleGroupBox widget. I receive the following error: ImportError: No module named ...
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1answer
24 views

Create different print composers from different layers added to QGIS

I'm using QGIS 2.8.3 with windows 10. I want to know if it's possible and how to create, using python code, from each layer (in the table of content) a print composer to each one of them. Any ...
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1answer
25 views

refresh programmatically created composer

I am trying to create a composer using pyqgis. Everything works as expected. The only difference compared to the manual creation of a composer is, that I am not able to update the layers (by pressing ...
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0answers
11 views

PyQGIS: intersection of one node layer with two polygon layers

I´m new with the use of PyQGIS and I´m working in a problem applied to a water supply systems modelling, where I need to distribute the water demand in about 5000 nodes (network junctions). I´m ...
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1answer
18 views

How to keep live update coming from a WMS

I'm using a WMS that contain weather radars that is update every 10 min. I would like to know how to keep the map updating every 10min. I tried: from PyQt4.QtCore import * timer = QTimer() ...
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1answer
26 views

Errror using the Simplipy QGIS plugin: 'QgsRasterLayer' object has no attribute 'selectedFeatureCount'

I am adding a raster in QGIS 2.14.1 and get this new error: AttributeError: 'QgsRasterLayer' object has no attribute 'selectedFeatureCount' I am not programming, just using a QGIS menu. I am using ...
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18 views

How do I change the pixel values of raster data from QGIS python plugin

I have been trying my hand at a QGIS plugin. The plug in reads raster layer data into an array, pipes the data to a C++ program, does processing over there, and pipes my results back. After a couple ...
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2answers
30 views

QGIS Segmentation fault when manipulating QgsGeometry

So I am running QGIS 2.8.1 on Ubuntu 14.04. This following problem is happening in my script, but also occurs directly in the QGIS python console: lay = iface.activeLayer() lay.featureCount() 1L ...
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1answer
132 views

Setting a default value in a QGIS field

I would like to add in a layer's field a default value. I mean, every time a new feature is created, that field would be automatically filled with the default value. In my case the default value ...
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0answers
27 views

How to add dynamic text in standalone PyQGIS to reflect iteration of layer names

I am working with a standalone PyQGIS script below (that was given as an answer to How to iterate over layers and export them as PNG images with PyQGIS in a standalone script). The script exports the ...
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1answer
60 views

Pyqgis : how to close composer window?

I would like to load new composers from template files (*.pqt) when I open my plugin. I managed to do it using this helpfull post Programmatically import new composer from template to project using ...
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1answer
439 views

ImportError: No module named qgis.core from PyQGIS?

Trying to load QGIS -- I have a working copy of Python: 2.7.9 -- It looks like QGIS is not finding PyQGIS. I am aware that this is a problem with the PATH but do not see how to fix it. > My ...
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1answer
50 views

Why does joining all layers in a group not work?

I am attempting to re-join all layers within a group to another layer ("Main.shp") outside of this group. The idea is for users to change values in one of the group's layers. As these layers are ...
2
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0answers
49 views

Deployment of optical fiber QGIS Python

The subject that I’m working on is the deployment of optical fiber . I have a shapefile which represents a country containing homes. And I have another shapefile representing an infrastructure plan of ...
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0answers
55 views

Problem using processing.runandload() [closed]

I'm writing a QGIS plugin using PyQGIS and I have a weird problem. When executing following line of code: processing.runandload("qgis:createpointsalonglines", r"Clipped", 1, 1, 0, r"memory:nodes") ...
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1answer
35 views

Label only selected features with PAL PyQgis using an expression

I'm trying to label only selected features with an expression using PyQgis and the PAL functions, but I don't find any example and the API don't help me a lot (or I don't found it). My Qgis version is ...
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0answers
33 views

The features don't appear at the first time in my exported PDF

my problem consists of exporting to PDF format. The first time I run my code (Text Editor of QGIS) the PDF only has the legend. But the second time, it has the features. Changing the line of ...
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0answers
45 views

Approach to controlling which layers display in a QgsComposerLegend

I've tried 2 approaches to control what shows up in print legends. Neither of them work which is troubling because other than pruning the layerRootTree in advance of composer.addItem(legend), there ...
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2answers
39 views

How to set the paper size to A4 for a PDF export with pyQGIS?

I have been developing this code, based on the official documentation of QGIS and some codes in gis.stackexchange. But my problem is that I don't know where to establish my height and width to make a ...
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1answer
65 views

Writing result of PyQGIS to shapefile

I try to perform some zonal statistics on a shape- and rasterfile and write the output to a completely new shapefile! import sys # where is the module ...
2
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0answers
22 views

addItem() method doesn't work [closed]

I show you my code, but basically, I have been following the steps in the official bibliography about Map Composition The code works, but I don't get the items I have been adding to the map (scalebar, ...
4
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2answers
174 views

How to render layer into png in a standalone application?

I would like to use standalone appliction to apply .qml style to a layer and use QgsMapRenderer() to save it as image on a hard disk. The are a lot of questions like mine at this site and it seems ...
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2answers
46 views

How to connect push button in dock widget form?

Following this tutorial as a guide, I created a plugin using the Plugin Builder with the dock widget form. I am now trying to connect a pushButton to a function. The following is a snippet of code: ...
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0answers
19 views

I can't define “enum QgsComposerItem::ItemPositionMode ” to UpperRight

In order to create a new map layout with labels, I have to set in my code the position of the labels with ItemPositionMode, but it the parameter is not accepted: from qgis.core import * from ...
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2answers
820 views

How to get the file paths of the loaded layers in a QGIS plugin?

I am very new to GIS, QGIS and Python so please bear with me. I am using QGIS 2.0 and I would like to develop a QGIS plugin that would display the raster layers of the main window in order to allow ...
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0answers
20 views

QGIS cannot load macro function?

This has me stumped. For some reason, I can no longer run a function from a project macro even though macros are enabled (from Settings > Options > General > Enable macros > Always). Just ...
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0answers
31 views

How to georeference *.tiff to a given feature geometry automatically?

I´ve got the task to georeference an tiff image to the referencing polygon footprint (Polygon). I have found a lot of ways to do get the footprint from a raster but I could not find a way to use ...
4
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1answer
50 views

Can't delete features from layer using QGIS' Python API

I've only recently started using QGIS and it's Python API. Currently I've loaded two OpenStreetMap datasets. I would like to remove lines with from the second set where the name is already present in ...
4
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0answers
49 views

Issues updating field values programmatically for particular field data type on 64bit Windows computer using QGIS 2.8.7

I have an issue with a plugin for QGIS 2.8 I'm developing when using it on a Windows 64bit machine (as opposed to 32bit). I am trying to update values in a particular field in my plugin, and the ...
2
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1answer
324 views

How to deactivate my custom tool by pressing the Escape key using PyQGIS?

I'm developing a QGIS plugin and I have created a custom tool. Once the process is over, if the user presses the ESCAPE key, I want my custom tool not to trigger mouse events on the map anymore. How ...
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12 views

There is a Run Time error wile using the console.in QGIS

I was writing a post where I have pointed in my code which lines of code "make" QGIS to fail. But as the time as I was writing the post, I tested the code again in the Text Editor of QGIS (2.14). ...
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2answers
29 views

How to read the saved extent of the QgsProject?

I am trying to access the extent of QgsProject. How can i do that with PyQGIS?
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2answers
44 views

Cannot load vectorlayer PyQgis

I am having a hard time loading a vectorlayer from the console. Not from the Pythonconsole within QGIS, but from the console on my computer. I later want to write a standalone script! That is what I ...
3
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0answers
159 views

How to change the group icon in legend via Python in QGIS 2.6?

How to change the group icon in legend via Python in QGIS 2.6? At version 1.x I did it this way: self.legendTree = self.iface.mainWindow().findChild(QDockWidget,"Legend").findChild(QTreeWidget) ...
4
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2answers
57 views

What's the correct syntax to use Processing gdalogr:merge from python?

I am using gdalogr:mergein Python console in order to merge to rasters (.tif) But I don't really understand the first parameter, where I have to put two variables. I get the following error: ...
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1answer
45 views

Error doing processing.runalg

I have been working in this code but I am getting the following error: Traceback (most recent call last): File "", line 1, in File "c:/users/miguel~1/appdata/local/temp/tmpdsyhqn.py", line 17, in ...
4
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2answers
50 views

How to get layers in x number of subgroups?

I have a project which has dozens of groups and subgroups. E.g.: Main_Group > Sub_Group_1 > Sub_Group_1A > Layer_1A > Layer_2A How can I access ...
4
votes
1answer
127 views

How can values in the attribute table be refreshed automatically when a geometry changes?

I can't find a solution for auto-refreshing attribute table data. For instance, how can the data related to features of a Shapefile (e.g., the area) be updated if the feature geometry is changed.
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0answers
30 views

Eclipse PyDev has quit recognizing QGIS objects

I followed the instructions for setting up Eclipse with PyDev to start creating QGIS plug ins found here: http://docs.qgis.org/testing/en/docs/pyqgis_developer_cookbook/ide_debugging.html after doing ...
0
votes
1answer
18 views

QGIS algorithm parameter: <ParameterString> [duplicate]

I have been working with the algorithm gdalogr:warpreprojectand have failed several times in the parameter in the title. Now, the problem is solved. It was about the EXTRA parameter. I read 3 books, ...
2
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0answers
25 views

How to programatically populate a field_4 after choosing values from other fields

I'm working with QGis 2.8, editing the attribute table of a SHP file, named "myTable". I need to populate field_4 with the conditions listed below: For 1 to n (it runs across records of myTable) ...
2
votes
1answer
38 views

Module Map Composer not found

I am using Map Composition, but I found in QGIS 2.14 (Essen) Text Editor that when I try to import MapComposerit returns that this module is not found. This is the error : File ...
2
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2answers
179 views

How to iterate over layers and export them as PNG images with PyQGIS in a standalone script

I would like to export specific layers as a png from a QGIS .qgs map. From the table of contents the script would first export the "boundary, climits, and Div1_Irrig_1956_0" layers as one png. The ...
2
votes
2answers
53 views

I don't get any output from Reprojection

I have recently posted a Reprojection issue. I found the solution, but now I can't get the output: I load the resulting reprojection by code, but first, I look into the folder where I have indicated ...
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0answers
7 views

Override renderDiagram method from QgsHistogramDiagram

I try to reimplement the renderDiagram() method from QgsHistogramDiagram to add some labels directly to the diagram (using the position argument). So far, I tried to set up my own class to override ...
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2answers
158 views

pyQGis scale based visibility problem

Im loading some layers from postgis using pyqgis in my standalone qgis app. For each layer i also load a style using: lyr.loadNamedStyle("style.qml") I've setup 2 versions of styles in qgis ...
2
votes
1answer
47 views

Algorithm fails (not found) : gdalogr:warpreproject

I am using the code in "QGIS Python Programming Cookbook", testing the code to learn about programming in QGIS. But when I try to reproject a raster, I get the error: Error: Wrong number of ...
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4answers
317 views

How to snap a road network to a hexagonal grid in QGIS?

I'm trying to use QGIS 2.14 to snap a road network to a hexagonal grid, but I'm getting strange artifacts. I've created a hex grid with MMQGIS, cells are approx 20 x 23 m. I've buffered the road ...
3
votes
1answer
132 views

How to change a project variable using Python?

I'd like to change the value of a user-defined project variable (can be manually edited in Project Settings | Variables) using the Python console. I tracked down the setVariable() function in the ...
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0answers
11 views

Can't get new layer from QgsGeometryAnalyzer [duplicate]

I have this user's problem as well. When I click "RUN" in the Text Editor in QGIS, nothing appears, and I haven't got any errors. It is a very symbply class but surprisingly, I can't get any result. ...