0
votes
0answers
6 views

export qgis point symbols per feature

I am currently trying to export the drawn symbol in a QGIS map for a webmap. The current approach is to extract the properties: if i.rendererV2().dump()[0:6] == 'SINGLE' and i.geometryType() == 0: ...
1
vote
0answers
17 views

QGIS 2.2.0-Valmiera 64bit on windows 8.1 displays error while creating ROI in SAC plugin

I don't know what happened while creating ROI during Classification using Semi automatic Classification Plugin 3.1.0 "Rome" installed on hp Pavillion i7 with windows 8.1 When i started to generate ROI ...
1
vote
1answer
32 views

How to open the “File Browse” dialog in Windows from a PyQGIS plugin code?

I am in the process of developing a plugin for QGIS using Python. Note that this is my first plugin, so the query could be quite basic... I have used this Digital Geography link to create the basic ...
1
vote
0answers
31 views

midpoint of segments in QGIS determination

Gene thanks for your note on the problem yesterday ... This is a follow up to a question I posed before (How to find the middle point of a line in QGIS - Where to place input file name). Errors coming ...
1
vote
0answers
38 views

Is there a python function in QGIS to detect if the output file is saved to the hard disk?

I'm currently using QGIS 2.4 and writing some custom scripts on it. A proper script not only accomplishes its function, but also accepts user defined parameters and checks for possibilities of errors. ...
2
votes
1answer
45 views

Adding new Field and writing values for all features

I need to create new Field in Attribute table of vector layer, and afterwards to calculate values and store them in that Field for all features I have in that layer. I have solution which works, but ...
1
vote
0answers
26 views

QGIS Add WMS layer with python

I'm developing a stand alone python script using QGIS 2.2.0 libraries. I want to add a WMS base layer to my map, and I follow the instructions reported by the documentation: urlWithParams = ...
0
votes
0answers
13 views

Using setCrsTransformEnabled in qgis 2.4

In the python console of qgis I try to load layers from shapefiles which have different CRS using the setCrsTransformEnabled() method. To test the procedure I changed the CRS of the shape file using ...
3
votes
0answers
41 views

How to create a python plugin in QGIS 2.4.0?

While I am learning to create a python plugin in QGIS 2.4.0, I have followed the proceedure expalined in ...
1
vote
0answers
14 views

PyQGIS: Properly trigger actionPan() tool when feature is added

I wrote a plugin which creates a custom map tool that adds features. I would like to cleanly connect to the pan tool after a feature is added. I've done it in the following way and it works, but I get ...
3
votes
1answer
26 views

How to refresh the view in QGIS Print Composer using Python?

I am trying to automate the printing of maps based on different attribute classifications using Python in QGIS. Everything is okay except for when I open the printed image, the labels are blurry. ...
0
votes
0answers
17 views

Export qgis vector layer to PostGIS table using python

I've created script, which does bunch of stuff, and in the end, I would like to export it to postGIS table. What is easiest way to do such export using qgis api or sth. I dont want to write SQL ...
2
votes
1answer
33 views

how to load the QGIS openlayers_plugin in standalone python script (not the QGIS embedded python console)

if I try to load the openlayers plugin in a standalone application it always fails with False, although paths are set, and plugin shows available. (tested on Ubuntu 14.04, QGIS 2.4, python-2.7) ...
0
votes
1answer
32 views

QGIS Python - Convert the CRS of an in memory vector layer

In a python script of qgis I load layers from different datasources using the QgsVectorLayer() and the QgsRasterLayer() commands. The coordinate reference systems of the data sources differs. Since I ...
1
vote
2answers
49 views

Creating a plugin tutorial

I am looking for a tutorial of how to create a plugin for QGIS. I want a tutorial that: Explains about the latest version of QGIS Working in windows environment. adequate for absolute beginners and ...
2
votes
1answer
44 views

Loading features attributes into 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. ...
0
votes
0answers
30 views

How to manage two map items in a QGIS composition with python?

I need to manage two different map items in the same map composition, with a stand alone python script. Each composer map has been referenced like this: composerMap1 = ...
2
votes
1answer
51 views

How to get into the Python API of QGIS?

After a few hours I am about to give up on finding a kind of documentation for the QGIS Python API that actually works/gives the correct information. It is obvious that there is no actual code ...
1
vote
1answer
23 views

QGIS raster calculator using abs() function

Is it possible to use the Abs() function in the raster calculator in QGIS? I've tried it, but it didn't work.
1
vote
0answers
24 views

QGIS processing framework SAGA NaturalNeighbor in external Python Script - No Output

I want to build a little script, which generates a NaturalNeighbor grid based on a point Shapefile. The script runs within my PyDev environment without any error messages, but no outputfile is ...
2
votes
1answer
66 views

ringer: help convert simple plugin to new QGIS 2.x

I have been trying to get this simple plug-in to work on QGIS 2.x. So far i got it to load, but it does nothing! all that it is supposed to do is place a polygon where a hole (ring) is. The code is ...
3
votes
0answers
23 views

Overriding the QGIS Feature Dialog

We are developing a QGIS plugin and would like to override the QGIS Feature Edit Form with our own Dialog. Have explored using setEditForm and setEditFormInit, but the init process appears to want to ...
1
vote
0answers
20 views

cadtool and spline plugins not working

Am trying to edit a line shapefile using a spline tool in QGIS 2.4.0 .Its drawing but the ok button is inactive. what could be the problem? Generally am trying to create a curved line.
1
vote
1answer
35 views

How to properly import QImage from PyQt4.QtGui?

I am starting with QGIS python console. Naturally, I came across the PyQGIS Developer Cookbook. While trying to cut my way through it, I encountered a lot of problems with "undefined attributes and ...
4
votes
2answers
45 views

How to programmatically delete all inner rings of a polygon layer?

I have many polygon layers, each layer containing many polygons with inner rings. I know that you can delete a ring manually with QGis (Edit -> Delete ring). I need the python equivalent to ...
3
votes
0answers
56 views

Problem with performance when loading PostGIS layer using pyQGIS

I'm having a question on loading a PostGIS layer into the project from my QGIS plugin. The code is like this: uri1 = qgis.core.QgsDataSourceURI() uri1.setConnection(str(host), str(port), ...
1
vote
1answer
28 views

Point input for polyline not acceptable?

Input QgsPoint(s) are returning an error in a Polyline creation routine. Any clues?! processing.runandload("qgis:polygoncentroids", Base, "memory:CenterNode") ...
1
vote
0answers
45 views

How to load style from postgresql?

Is there any way to load a postgresql style for a vector layer using python? There is a function: loadNamedStyleFromDb (const QString &db, const QString &theURI, QString &qml).Does it ...
1
vote
0answers
20 views

Problem Loading Plug-Ins in QGIS 2.2 on Mac

I'm trying to load the 'processing' module in QGIS (2.2.0-Valmiera on Mac OSX 10.8). However, this module and others (e.g. GarminaCustomMap) re failing to load with a message: ImportError: No ...
3
votes
0answers
47 views

Create vector grid from canvas using script

I've modified "Hex grid from layer bounds" script to my need. Just added cellsizex and cellsizey. Changed the hexagonal - 3 to "1" to make it as a square grid. Is it possible to include an option to ...
0
votes
1answer
57 views

Cannot load postgis layer from sql string in pyqgis

I'm trying to load a layer using the following code in qgis python console: sql = "(select the_geom, ID from mytable)" uri = QgsDataSourceURI() ...
1
vote
1answer
48 views

What's the reason for this Invalid Layer “Cannot open GDAL dataset …” error

When adding a rasterfile with QGIS python console there appears an error when the first letter of a rasterfile to be added is not written in capital letters. Why this behaviour? Example case1: ...
3
votes
2answers
71 views

Converting huge multipolygon to polygons

I have a shapefile with some huge multipolygons, with 100.000's of parts. What would be the easiest way to split them to singlepart polygons? I'm looking for something like QGIS ”Multipart to ...
0
votes
1answer
26 views

QGIS Python console - save image from bounding box

I want to save an image from QGIS but the save image functionality feels limited. My question is if it's possible to use the python command line to save an image at a specific zoomed in scale and to ...
1
vote
1answer
27 views

pyQGIS - Data Source is Invalid

Why I am getting Data Source is Invalid in python console of QGIS when running: vlayer = QgsVectorLayer("home/sanjayr/Desktop/india-latest.shp/buildings.shp","sanjay","ogr") I am using QGIS 2.4 on ...
1
vote
0answers
35 views

Clipping between features within a single vector?

Is it possible (via the Qgis API and friends), to clip polygonal features within a single vector layer? The hope is to accomplish this without having to duplicate the feature into a new layer. ...
3
votes
0answers
51 views

Performing buffering and intersection with script in PyQGIS

I wrote a script that performs the intersection of two layers: The first Layer -> layer1, represents the rivers The second Layer -> layer2, represents a set of circular dots distributed in a ...
2
votes
1answer
57 views

QGIS way to import OSM/Google Maps but remove or exclude extraneous areas, limit geographically the use of OSM

GIS Newbie question, perhaps: But I am looking to place an Open Street Maps/Google Maps layer underneath the rest of my shapefiles for referencing purposes. Let's say for instance, that I am looking ...
1
vote
1answer
83 views

Why is feature.geometry() None in my user-defined expression function?

I'm trying the user-defined expression functions for QGIS, as listed on Nathans blog: http://nathanw.net/2012/11/10/user-defined-expression-functions-for-qgis/ I always get the feature.geometry() as ...
1
vote
0answers
41 views

Scaling features based on an attribute

I would like to scale polygon features by a specific factor I have calculated for each feature in a feature class. I know of the Scale tool, however it only allows for manual entry of a scale factor ...
0
votes
0answers
32 views

QGIS plugins - how to use a custom behaviour on right click and actionPan on left click?

I have been struggling with this problem for quite a long time. Here we go : I implemented a maptool that draws a red cross on the point that is being right-clicked on. There are good how-tos, such ...
4
votes
1answer
71 views

How do you set the position of a plugin window when you start the plugin?

I'd like to set the position of a plugin's window or dialog relative to the map canvas frame. For example, if I start a plugin, I want it to appear somewhere in the left upper corner of the map ...
0
votes
1answer
53 views

How to add new columns with attributes in existing Qgis layer?

How to add new columns with attributes in existing Qgis layer? Doing the "same thing" here described
4
votes
1answer
54 views

Can QGIS map canvas update while python script is running?

I want to automate a periodic refresh of the QGIS map canvas with updated shapefiles. A Python plugin or console script does not allow the map to update until the script terminates. Is there a way to ...
2
votes
1answer
72 views

Python console not working at all

My python console won't work at all. I can't open it. My QGIS version is 2.4. OS is win7 64. I've reinstalled QGIS a few times but I always get the same result. Strange. Something went wrong with the ...
1
vote
1answer
54 views

Programmatically export a Qgis project

I have a QGis project that I programmatically modify using the Python xml.etree library. Now, I would like to know if it is possible to add few lines to my script in order to export the modified ...
4
votes
1answer
124 views

Can ArcGIS ModelBuilder be exported to Python and run in QGIS?

Is it possible to construct a geoalgorithm on the ArcMap modelbuilder, export this entire algorithm to python syntax (without having ANY knowledge of python) and then import this algorithm to QGIS and ...
3
votes
1answer
59 views

No get more option in QGIS

I have recently installed QGIS and trying to work with it but I don't see this option "Get More" at all. As suggested by some previous source, I also checked whether I am behind a proxy but that isn't ...
1
vote
0answers
32 views

pyQGIS 2.0: Sending signal when identify button is pressed via gui

I have a question regarding the qgis identify tool for version 2.0. I would like to know if it's possible to send a signal when the actionIdentify is triggered by the user via the gui. I'm trying to ...
3
votes
0answers
67 views

QGIS API - Print Composer Template produces empty map?

I have a print composer template which I'm trying to populate with different subset queries from a CSV-derived vector layer using the Python API. However, all the output PDFs contain everything except ...