Python bindings for QuantumGIS (QGIS)
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2answers
74 views
Get features by their attributes in Qgis using python and SQL filters
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
191 views
Creating Selection MapTool in PyQgis Custom Application
I'm developing a custom GIS application using PyQgis API.
How can I let the user select features on the map using Maptools? I would like to replicate the select feature there in Qgis to make the ...
1
vote
1answer
387 views
rpy2 installation ERROR “Tried to guess R's HOME but no R command in the PATH”?
I tried to install rpy2 (pip install rpy2). I want to use the SDAPP4 extension with QGIS (QGIS shows up the message missing rpy2...). The system tells me always the same error: Tried to guess R's HOME ...
1
vote
1answer
117 views
Color depending on attribute
I'm trying to set the color of a vectorlayer feature depending on the feature attributes with PyQGIS. How do you acces the attributes of a vectorlayer feature?
0
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1answer
51 views
How to save after using fet.setFeatureId in pyQGIS?
By using the following code, I want to change the id of the line when saving the line. But the setFeatureId command, gives a false when doing the commitChanges(). Any idea how to change the id?
vl = ...
3
votes
0answers
394 views
How to find all intersections and count lines arriving at each intersection?
I'm having a hard time getting off the ground with this, and am trying to move away from ArcGIS / arcpy.
I have a shapefile with a network of polylines. I want to find/count all 2-way intersections, ...
2
votes
0answers
51 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
votes
0answers
349 views
legend groups and layer position/order qgis 1.8
I'm tring to programmatically create layer sequence also using groups.
Simple python code:
layer = QgsVectorLayer("004cp000.shp", "004cp000", "ogr")
QgsMapLayerRegistry.instance().addMapLayer(layer)
...
1
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0answers
52 views
How to delete a point with known coordinates in python?
I was wondering if there is a piece of code that does the opposite that setGeometry does and removes a point if there is one at x and y coordinates?
1
vote
0answers
119 views
DLL problem with PyQGIS
I am having problems with Python Shell importing the module "qgis.core".
When I type "import qgis.core" the Shell ("idle.pyw") gives me this error:
Traceback (most recent call last):
File ...
1
vote
0answers
158 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 ...
1
vote
0answers
42 views
What is the proper way to do an automatic rollback of a vector layer edit?
I'm trying to rollback automatically the changes in features of a in-memory vector layer that don't meet certain criteria.
The code I'm using for testing looks like this:
...
def some_function()
...
1
vote
0answers
97 views
Is there any python function to rotate map layers?
Is there any python function allowing a user to rotate map layers in the map canvas. If so, could you please point this out for me?
I want to rotate a map layer, using a factor of rotation in ...
1
vote
0answers
129 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 ...
1
vote
0answers
52 views
SVG markers with PyQGIS
How do you SVG-marker layers in PyQGIS? I'm importing a vector layer and want to display it with SVG-markers.
It seems that QgsSvgMarkerSymbolLayerV2 does not exist in PyQGIS...
1
vote
0answers
141 views
no module named core
Hi I am trying to access and use QGIS modules/class/methods from IDLE on a mac. I have had the same problem as a few other people, and browsing the forums have tried to follow the advice they have ...
1
vote
0answers
230 views
How to change feature's geometry?
Hy,
I'm creating my layer like this:
crs = core.QgsCoordinateReferenceSystem(4326, core.QgsCoordinateReferenceSystem.EpsgCrsId)
uri = "Polygon"
uri += '?crs=' + crs.authid()
uri += ...
1
vote
0answers
133 views
QGIS Updating composer label text via python - problem with Item Properties panel
I am writing a plugin that replaces the text of a composer label based on its itemID.
When I change the text of the label using:
item.setText("Hello World")
the label changes on the composer but ...
1
vote
0answers
72 views
Setting border-style to 'no pen' using QgsGraduatedSymbolRendererV2
I am developing a QGIS plugin that, after a series of inputs, will produce a thematic map using the QgsGraduatedSymbolRendererV2. Because the polygon are very small, the boarders make it such that ...
0
votes
0answers
44 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 ...
0
votes
0answers
42 views
How to begin with tool development for GRASS gis or QGIS GRASS
I wanted to begin with customized tool development in Grass GIS or QGIS grass. How should i begin in to develop the tool. I search a lot in google search engine for begin with tool development in ...
0
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0answers
102 views
how to plot point on openlayer google street layer programmatically
I want to plot points on google street layer using python programming and postgresql database.
Mainly I want to extract data from database and plot it on the google street layer on Quantum GIS 1.8 ...
0
votes
0answers
36 views
Associate media to gpx vector layer from Python Console
Essentially, I would like to have the description in the form of text annotations when i hover my mouse over the gps entry. And if i click the same, it should display the images.
So I started off by ...
0
votes
0answers
99 views
QGIS python console projection transformation
I need to write a python console script in QGIS to do the following:
1) convert a simple KMZ to a shape file format
2) reproject from WGS84 to British Grid (OSGB_1936)
This is to automate the 2 steps ...
0
votes
0answers
184 views
Qgis python plugins development with Eclipse
I'm using Eclipse's PyDev extension to develop python plugins for Qgis.
I did the required configs for the interpreter in Eclipse to be able to use python.
When I start a PyDev project, all the Python ...
0
votes
0answers
94 views
How to build QGIS with Python on Redhat?
I'm attempting to run QGIS on Redhat 5 64 bit architecture. Version of Python is 2.4.3. Version of QGIS is 1.7.4 (wroclaw).
When I run qgis, the splash screen appears, followed by a QMessageBox that ...
