Software plugins that add functionality to the QGIS package

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7
votes
3answers
3k views

How to extract slope from topographic raster map?

I am working on a project for a machine learning class wherein I extract features from a topographic raster map and then classify the traversability of the terrain. One of the features I need to ...
3
votes
2answers
969 views

How to debug 'Layer is not valid error' from Python plugin?

I'm trying to understand what goes wrong with a QGIS python plugin. Basically I'm trying to render a series of POINT. The query works fine, at least giving it by hand from inside PostGIS DB: "SELECT ...
2
votes
1answer
3k views

TIN Interpolation using a vector layer

I'm writing a plugin in QGIS and I'd like to generate a TIN surface using a vector layer with x,y and z (interpolation attribute). The idea is to visualize the same result like in the Interpolation ...
8
votes
1answer
341 views

How to debug a QGis python plugin

I'm trying to write a python plugin for QGis. I'd like to debug some DB queries and I need a way to display the result. I thought about using a popup to display it, but I don't know how to show a ...
1
vote
1answer
74 views

Can't find the New label tools in QGIS

I can't find the New label tools in QGIS developed by sourcepole. I'm using QGIS 1.7.4. Is it a QGIS tool or a pluggin? Thanks!
4
votes
1answer
1k views

Unit of $length in QGis Field Calculator

I'm calculating field of various features in my shapefile using QGis. I'm getting some sample length as 0.134914579766986. I want to know in what unit (eg: meters, km etc) is the above value ?
1
vote
2answers
197 views

Length of Feature

I have a shapefile which renders a map. I want to calculate and preferably store length of each feature in the shapefile either using QGis or through programmatic means. What is the best way to get ...
2
votes
1answer
337 views

How to move the QGIS Layerpanel/Dockwidget programmatically

i'm working on a QGIS-plugin and want to move the default LayerPanel/Dockwidget to somewhere else programmatically. More specific: i want to move it into a tab of my tabwidget. Is this possible? How ...
2
votes
2answers
319 views

Cannot add Plugins from Python: “Plugin is Broken”

I'm using the latest version of QGIS on a Windows 7 (32 bits), and when I try to add a plugin from the option "Fetch Python Plugins", it simply cancels the installation and I can see the following ...
1
vote
0answers
141 views

Error reading repository: QGIS Official Repository HTTP request failed

I can't seem to access the plugin repository. Is this an issue with my system or is there something going on at the server end?! I get the following error as wells sometimes a window saying: "Error ...
0
votes
0answers
192 views

Why are my combo boxes not filled with a list of layers?

I am developing a Qgis plugin (layer_gui) and I am having a problem with populating the list of layers. When I first run the plugin my combo boxes are not filled with a list of layers, I have to ...
3
votes
1answer
297 views

Does QGIS DB Manager plugin lock PostGIS transactions?

I do most of my geospatial analyses in PostGIS 2.0 using PgAdmin III. I use QGIS 1.8 for visualizing my data but also for querying my database using the DB Manager plugin. Sometimes (quite often ...
6
votes
1answer
94 views

How to get info from selected object?

I am new to the Quantum Plugin development and wonder if there is more information about the following. I have added a shape file and am (off course) able to select a point from this shape file. In ...
3
votes
1answer
741 views

Which parameter values should I use with QGIS Heatmap plugin?

I've read all the posts and docs about the heatmap plugin but can't seem to get it to work. The map is the size of the United States and has a little over 2000 points. I've tried small radi (1 ...
1
vote
1answer
277 views

QgsVectorDataProvider.createAttributeIndex() fails in QGis 1.8

Adding an Attribute Index to a Shapefile fails for a Python Plugin in QGIS: For example - the following python Code in a Plugin ly = QgsVectorLayer(data_source, layer_name,"ogr") prov = ...
2
votes
1answer
133 views

plugin 'hook' when writing with Python

Just a conceptual question... when writing a plugin using Plugin Builder 1.8.3, where does the script get connected to the application instance objects? As an example (taken from ...
1
vote
1answer
177 views

Is there a straight way to copy or clone a QgsVectorLayer Object?

Is there a straight way to clone or "deepcopy" a QgsVectorLayer Object with python? Unfortunately the python module "copy" is not successfull with that. Thanks in advance! nikolaus
3
votes
1answer
672 views

Where is the Road Graph panel?

I am trying to use the Road Graph plugin within QGIS 1.8 (running under Windows 7 64-bit). When I click Vector -> Road Graph -> Settings I get the settings-panel: But, I don't know how to enable the ...
2
votes
1answer
684 views

How to meet “Contour plugin” and “Profile Tool” dependencies in OSX?

So I have two similar but different issues than my previous question, one I may have mentioned already. When attempting to install the Contour plugin I am told I need matplotlib, which I have on my ...
1
vote
1answer
198 views

QGIS Profile from Line tool requiring shapely.wkd?

I am trying to install the Profile from Line tool for QGIS, and the system informed me I need shapely.wkd. A search on the QGIS site for shapely takes me to the Contour Plugin...can anyone help me out ...
2
votes
1answer
1k views

QGIS GDALtools plugin problem

I am trying to use the GDAL merge tool and receive the following error message: The process failed to start. Either the invoked program is missing, or you may have insufficient permissions to ...
2
votes
0answers
58 views

Is there a way to distinguish between digitized and pasted features?

Is there a way to tell if an added feature in QGIS is in fact a newly digitized one or a pasted feature? I think QGIS is treating both cases in the same way, emitting the same signal: ...
4
votes
2answers
248 views

What is the fastest way to iterate through a list of features?

I have written a QGIS plugin and it iterates through all features in a layer using provider.select() and compares geometry. The problem, the plugin is very slow. If there are 114 features in a ...
5
votes
1answer
102 views

Is it possible show the feature attributes dialog when I add a feature in code?

I want to know if it is possible to make the feature attributes dialog in Qgis show up when I add a feature by code using: QgsVectorLayer::addFeature( tFeature ) This is available when I add ...
1
vote
0answers
574 views

QGis CadTools CAD Console

I need help with the Qgis CadTools CAD Console commands. According to these help files there are six commands. I just can't get them to work. Can someone help me? Thanks
3
votes
1answer
211 views

How to use the QgsDiagramRendererV2?

I'm writing a plugin for QGIS in python in the QGIS API doc, I can see the QgsDiagramRendererV2 class, under the qgs.core section http://www.qgis.org/api/classQgsDiagramRendererV2.html What I'm ...
2
votes
0answers
289 views

Postgresql Query Plugins Not Returning Results in QGIS

I'm using the Fishnet function as described here to create a grid. If I use the following SQL to call the function to position a grid where I want it (I'm using NZGD2000 SRID = 2193) the query ...
7
votes
2answers
371 views

How to run a spatial query with a raster and vector layer in QGIS?

I have a soil map (vector-polygon layer) and a map of the crops farmed in the same area (raster layer, from the US Cropland Data Layer). I would like to calculate for a given soil type, the surface ...
3
votes
1answer
185 views

How to get raster layer pixels contained in a shape defined in a vector layer

I am new in QGis python plugins dev and I have a "maybe stupid" question (in the title :-) ). I try to retrieve pixels (from a raster layer) which are "contained" in a polygon defined in a vector ...
2
votes
1answer
195 views

Qspatialite plugin problems with queries using inner join

I'm trying to create a layer in QGIS from a sqlite database using a query from 2 tables: one has spatial data and the other doesn't. When I build the query using Qspatialite using the 'Advance SQL ...
2
votes
0answers
62 views

QGis, add dialog and classes to plugin

what are the steps to add files that represent a uidialog(draw with QTDesigner), and add the necessary python class files, using the default makefile provided with qgis plugin builder? thanks,
1
vote
0answers
77 views

How to find a feature on map by its field data

I'm using QGIS 1.8.0 & got much help to find a Featuer using 'Quick Finder' plugin. Is it possible to locate a Feature (using a similar plugin like'Quick Finder'), on map using its attribute data ...
3
votes
2answers
2k views

How to use QGIS Photo import plugin?

I have a lot of Photos with lat, long, and altitude information. When I start the import, I get an error message. Do I need to prepare a blank point layer before importing? Is there another python ...
1
vote
1answer
169 views

QGIS python plugin, segmentation fault, what can I do?

I'm trying to write a python plugin to create an input file for an urban climate model out of three shape files. Unfortunatelly QGIS closes when I try to load the plugin. When I start QGIS from the ...
2
votes
0answers
464 views

Qgis Plugin development with postgres data

can someone help me with initial developing on qgis plugin that displays postgres data table on a QTTableView or QTTableWidget? So far: I can connect to database using psycopg2 or using ...
11
votes
2answers
6k views

How to check Topology in QGIS?

I have two Shapefiles with Polygons ( City and Forerst) Is there a Plugin who is able check the topology (QGIS)? Like "Knots do not overlap" or something like that? I dont want that they overlap. ...
4
votes
1answer
4k views

What's the proper format for WKT linestrings when importing into QGIS?

I'm trying to run the following test CSV through the Delimited Text plugin as WKT data: oid,Line 1,LINESTRING((45.554194 -122.686101, 45.433001 -122.762632)) 2,LINESTRING((45.432505 -122.598327, ...
1
vote
1answer
519 views

Is there a way of viewing a photo has a point tag from Photo2shape in QGIS?

Is there a way to view images (photos) that have location point from Photo2shape by clicking on the point in QGIS?
1
vote
1answer
401 views

Polygonizer plugin for QGIS halts in Windows?

I've had some success and some problems using the Polygonizer plugin in the past. I'm using Polygonizer 2.1 in QGIS 1.8 on Windows 7. I'm aware there are sometimes problems using Polygonizer in ...
2
votes
1answer
2k views

How to save a vector layer from QGIS to Sql Server 2008 or 2012?

using QGIS, i've loaded up some administrative boundary data of New Zealand. I wish to now import this vector data from QGIS into my Sql Server 2012. Is there any way to do this with QGIS ...
5
votes
2answers
1k views

Where can I find documentation on QGIS C++ Plugin Development?

Is external C++ plug-in support available for QGIS? I'm having a really hard time getting started here. I followed the doc here: ...
4
votes
1answer
766 views

How to Create a raster layer from a numpy array using pyqgis?

I am working on a plugin for Qgis to calculate spatial Kernel density maps. I have all the calculations working, all I am missing is a way to turn a Numpy Array, with density values into a multiband ...
2
votes
0answers
408 views

How to access mysql data from python built-in console?

I'm writing a QGIS Plugin, and somewhere I want to present data from a MySQL database. It's simple data(strings,etc), not Geospatial, or vector data. I'm familiar with querying databases from python ...
0
votes
1answer
319 views

Problem in Spatialite database creation

When I try create a new DataBase, Spatialite plugin return the dialog error box: The SQL query seems to be invalid. no suck table: views_goemetry_columns When I click in OK button, a second dialog ...
2
votes
2answers
149 views

Invalid Username When Developing a QGIS Plugin on Mac

On a fresh Mac OSX 10.8 install, I've installed Quantum GIS from Kingchaos binaries and it's running fine. I'm trying to develop a plugin for QGIS using Plugin Builder. The skel that Plugin Builder ...
5
votes
1answer
780 views

Is there a purge function to remove layers from a qgs file which are not present in the Layers pane?

I have some QGIS projects that I've been using for long time, adding and removing layers, updating reference to deleted or moved files etc. Opening with a text editor the qgs file I see that it ...
4
votes
1answer
2k views

QGIS: How to load feature (.qml) styles from python? [duplicate]

Possible Duplicate: How to style a layer from console? I'm trying to set the styles for a vector layer by loading the .qml file in the python console. The qml-style file contains all ...
2
votes
0answers
86 views

How to call a method when self.iface.actionSelectRectangle().trigger() is released?

In my QGIS python plugin I use "self.iface.actionSelectRectangle().trigger()" to select features. I also have a button which changes the attributes of the selected features. Is there a way instead ...
3
votes
1answer
283 views

What is status of OpenSceneGraph (OSG) plugin for QGIS? [closed]

Does anyone know if the OSG plugin for QGIS is working? If so does anyone knows what the future plans is for OSG plugin in QGIS? I am using QGIS version 1.8.0-Lisboa. I keep getting the following ...
4
votes
2answers
602 views

How to enable GRASS plugin in QGIS 1.8.0 (Linux Mint 13 - 64 bit)?

Every time I enable GRASS plugin in QGIS (Plugins -> Manage Plugins -> GRASS), I got a message: Exception - G_getenv(): Variable GISDBASE not set. I googled and found some information here but don't ...