Python bindings for QGIS.

learn more… | top users | synonyms (1)

3
votes
2answers
272 views

Programatically use Openlayers plugin layer in Print Composer

I created some PyQGIS functions to set up a print composer, modify the layout (adding maps, legend, title...) and print the result as an image file. This works fine with one or several vector layers - ...
3
votes
3answers
147 views

Drawing some points in QGIS 2.4 using Python

I'm new to PyQGIS so here goes: Give a new QGIS project, how can we draw some Points on the map? I tried the following but nothing showed up. Should they be placed in a Vector layer before they can ...
3
votes
2answers
105 views

Is there function to know raster's size (KB) with python?

I am doing a script with python. There I have many raster in canvas (qgis) which I would like to know size in MB. I am searching function in python that give me this result. Anyone can help me? Thank ...
3
votes
2answers
147 views

How to remove/disable a toolbar via python?

How do I remove or disable a toolbar e.g., Raster, programmatically using Python?
3
votes
1answer
325 views

Got Null values when updating attributes with PyQgis

I'm trying to create and update a field and ,for now, just change it's value to 2. Here is my code: layer = qgis.utils.iface.activeLayer() index = layer.fieldNameIndex("P") # if index == -1: # ...
3
votes
1answer
589 views

QGIS python - identify and highlight features programatically

In QGIS there is an option to select features of a selected layer using a "identify feature" tool. Then the feature get highlighted in a different color and attribute dialog is poping up. like that i ...
3
votes
1answer
257 views

How to apply a color gradient to a shapefile from QGIS console?

Anyone knows how to do a color gradient from the console to a shape file in Qgis (orin Python)? Like the image below.
3
votes
1answer
847 views

How to generate a grid programmatically in Python without GUI?

Is there a QGIS Python binding for generating a grid programmatically without using the GUI?
3
votes
3answers
2k views

QGIS 2 Python error on Mac OSX

Have just installed newly released QGIS 2.0. I installed the gdal package available at the official kyngchaos site. It seems to run ok, but when the program loads up I get a lengthy error message ...
3
votes
2answers
124 views

How to avoid the CRS Dialog when creating a vector layer memory?

I am trying to create a vector memory in a plugin. Basing on some examples,I was able to create a memory vector layer and to add it in QGis with : QgsMapLayer.instance().addMapLayer(myLayer,True) But ...
3
votes
1answer
378 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 - ...
3
votes
2answers
81 views

Using folder wildcards to copy files with Python

I would like to copy the data of one specific shapefile from a specific folder ("Grid") to a number of folders containing the name "Country". The country shapefiles would keep their original name. ...
3
votes
1answer
144 views

Programmatically grouping multiple layers into separate groups using QGIS?

I'm trying to group a large number of layers together based on a common portion of name string. They are a mix of polygons and points. I would like to create individual groups by using part of the ...
3
votes
1answer
79 views

How to change the edit widget for fields in a layer with PyQGIS?

Is possible change the edit widget with PyQGIS? I have made an extension that loads a PostGIS layer and I want to edit the date fields with the date widget by default without any change in the ...
3
votes
1answer
73 views

How to import fromUtf8 in QGIS?

# Declare instance attributes self.actions = [] self.menu = self.tr(u'&City_searcher_plugin') # TODO: We are going to let the user set this up in a future iteration self.toolbar = ...
3
votes
1answer
109 views

How to show Python console at QGIS program start

I wonder if there is a way to open the Python console of QGIS 2.6 directly at program launch. There is a possibility to set a shortcut for the Python console, but I can't find such an option for the ...
3
votes
4answers
122 views

QGIS Plugin with save settings dialog

I am writing on an update of the qgis2leaf plugin. It would be great to store the settings of the plugin UI (like which checkboxes are checked, which strings are used) in a separate file (like xml or ...
3
votes
1answer
2k views

PyQgis question: How to change or set active layer?

Developing a qgis plugin, I found that if no layer is selected in the Layers panel I can iterate over all layers and do anything to them, but "activate" them. Could someone give me a hint please? ...
3
votes
1answer
178 views

Can one expose variables to the Python console from a plugin in QGIS?

I have a QGIS plugin that performs a long-running operation, eventually producing and loading new shapefiles into QGIS. (I have this as a plugin rather than just a function that can be called from the ...
3
votes
2answers
442 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??
3
votes
1answer
1k 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 ...
3
votes
1answer
456 views

Is it possible to programmatically add calculated fields?

In the Memory provider described in PyQGIS Cookbook or in question How to create a new empty vector layer programmatically? I can see how to create a vector layer programmatically using standard ...
3
votes
1answer
832 views

qgis.core import error

I would want to use the Qgis api for custom desktop application. When I imported the qgis.core module, I get the following error >>> import qgis.core Traceback (most recent call last): ...
3
votes
2answers
105 views

How to add a legend to a canvas in a standalone PyQGIS application?

I am trying to develop a standalone PyQGIS application. The map display does not pose any problems, but I do not know how to add a legend to the canvas.
3
votes
2answers
79 views

How to access checked layers in PyQGIS?

qgis.utils.iface.activeLayer() accesses the current active layer, but I would like to get all checked layers in the QGIS ToC. How can I do it?
3
votes
1answer
72 views

Calling canvas.saveAsImage from script in QGis -Qstring problem

I want to create a processing script that saves the QGIS MapCanvas exactly as it is seen on the screen and then Zip up the tifw and a created PRJ. The existing QgsMapCanvas.saveAsImage()-method does ...
3
votes
1answer
147 views

How to make serial maps from template?

I have developed a stand-alone python script for making serial maps using PyQGIS library. The maps should follow a specific format that is indicated by a template .qpt file. This template file is ...
3
votes
2answers
85 views

Rotating geometry to specific angle using pyqgis?

I do not know how to rotate a geometry using pyqgis. Is there any sample/example code available to show me how?
3
votes
1answer
79 views

QgsMapCanvas.reresh() does not reload new wfs layer features, but panning does

I have a wfs layer loaded in a standalone QGIS app, which I am updating by running a database query on the view it is based on. The feature is added with no problems and I reload the layer with: # ...
3
votes
2answers
273 views

Pyqgis 2.2 : zoom to layer extent?

Regarding my plugin pyqgis 2.2, i can load a vector layer succesfully. But when i try to zoom to the layer extent it does not work. How to do in order to zoom to the layer extent? Thank you very ...
3
votes
1answer
267 views

Looking for help for automatically making a QGIS map

Im looking at making a standalone script, that on execution will run the QGis MapComposer using a previously generated template and output a PDF/PNG of the map. This process of making a map will be ...
3
votes
1answer
814 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
460 views

How to calculate all paired shortest path using PyQGIS?

The code for shortest path analysis with PyQGIS specifies start and end nodes explicitly: pStart = QgsPoint( -1.37144, 0.543836 ) pStop = QgsPoint( -1.1027, 0.699986 ) ...
3
votes
2answers
1k views

PyQgis overwrite shape file and adding layer to Qgis

I am creating a shapefile in python by: driver = ogr.GetDriverByName('ESRI Shapefile') datasource = driver.CreateDataSource('c:/temp/toke2.shp') layer = ...
3
votes
2answers
204 views

Merging polygons at county level to state level

I have a shapefile that represents counties (admin 2) only, but I need to create a state level (admin 1) polygon file (I'm using QGIS). I will need to sum up (or average) the relevant data at each ...
3
votes
1answer
785 views

Changing attribute data types using PyQGIS

OK, so I've already asked a question how to access attribute data types when developing plugin for QGIS, using PyQGIS. And one helpful member said i should use pendingFields() method on the current ...
3
votes
2answers
68 views

How to define layer's CRS and avoid the CRS dialog in PyQGIS?

There is an existing Shapefile, which I want to add. At the moment my code looks like: self.iface.addVectorLayer(self.shpFilePath, "Track", "ogr") It works fine, but i want to define the crs ...
3
votes
2answers
124 views

Join table field with shapefile programatically (via PyQgis)?

The following is currently unsuccessful at fulfilling a table field join to a point shapefile in Qgis. All instances of the join object will print the proper values, and no error is flagged when ...
3
votes
2answers
52 views

Send signal when attributes modified - QGIS 2.6

For a QGIS 2.6 python plugin, I am trying to send a signal when an attribute value is changed (values for an existing feature are updated or added and the attribute form dialog is accepted). This ...
3
votes
1answer
75 views

How to add a column/feature with PyQGIS 2.x?

I'm using PyQgis 2.2 and I'm creating a plugin. I want to add one feature/column to a shapefile. But I get error.. I've tried to do this as it's shown in Cookbook: if caps & ...
3
votes
1answer
86 views

Removing a vector layer from QGIS [duplicate]

Considering my program is generating a shapefile that has to be added to the "Layers" tab in QGIS interface. However, once the utility of the layer is completed, I need to remove the layer in the ...
3
votes
1answer
553 views

Problem with import qgis.core when writing a stand-alone PyQGIS script

I am trying to write a stand alone python script in windows 7 that uses qgis.core and various other qgis libraries. I have found an old question on this subject here: How to write standalone Python ...
3
votes
1answer
90 views

Getting random values from geometryType() in a standalone PyQGIS script

I am asking this question based on the result I received from this earlier post. The following script only works if I set geometryType() == 3 as that is what is being printed out in the Python console ...
3
votes
1answer
62 views

Making QGIS buttons and my Plugin button mutually exclusive

I've added a toolbar to the QGIS main window and I've added some checkable buttons to the toolbar. How can I make my checkable buttons untoggle QGIS default toolbars' checkable buttons? That is, ...
3
votes
2answers
257 views

Setting layer visibility in QGIS Python API

Im having a problem toggling the visibility of map layers in pyqgis (2.4). I have a simple interface, just the map canvas, no legend, and basically a radio button that toggles between two raster ...
3
votes
1answer
92 views

Find Polygon in “Layer A” containing Polygon in “Layer B”

I haven't found yet someone with the same problem, so I'm posting a new question. The topic seems quite standard, so I'm sure there's a way to do it in QGIS. I have two layers: Region Layer Postcode ...
3
votes
1answer
243 views

How to find the id of the last added feature using pyQGIS?

Is it possible to programmatically (in python) access the attribute info of the last added feature in QGIS 2.0 before edits are saved? I'm failing to find a way to get the ID and subsequently other ...
3
votes
1answer
89 views

Referencing Qt UIs external to plugin with python

I'm developing a plugin that sets up a working environment for a user: loading layers (from db), applying styles and several custom designed (Qt) UI files etc. Primary user interaction is in the ...
3
votes
1answer
48 views

How to store the CHANGES to a map database

I'm looking into providing a map amendment service for a particular map series. The service will help map owners look into the changes made to the operational features of the map, after the map was ...
3
votes
1answer
157 views

Workflow Scripting in QGIS

I have created a hexagonal grid shapefile using MMQGIS and want to use this for hexagonal binning. I have another point shapefile which contains patient records for three different types of hospital ...