QGIS is a cross-platform GIS application licensed under the GNU General Public License.

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118 views

Problem loading the contour plugin

I have installed the contour plugin on my kubuntu 13 laptop, but when I am opening qgis (2.0.1) I get the following message: Couldn't load plugin contour due an error when calling its classFactory() ...
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2answers
335 views

How to read Oracle data with PyQGIS? (“identifier is not long” error)

Do you have any idea how load Oracle spatial data to QGIS with using the PyQGIS? Is it possible? I try: uri = QgsDataSourceURI() uri.setConnection("*host*", "1521", "*database*", "*username*", ...
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1answer
39 views

Maintaining times with points2one in QGIS?

I have a problem that might be trivial, but I really cannot find a solution! I have a csv files with several points (x,y). These points represent the position of different animals at different ...
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0answers
166 views

Converting Shapefile Elevation field to Height Field

HAve been trying to update the elevation field in my shape file (vector file *.shp) into a height field. Have tried to rasterize the shapefile then deduct the height using Raster Calculator with a ...
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1answer
214 views

QGIS: Expression WHEN property1 = 'FOO' THEN property2 = 'BAR'

Our Foundation is adding additional properties to points. If property1 = FOO , then add property2 = BAR WHEN property1 = 'FOO' THEN property2 = 'BAR' END When I run this the ...
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0answers
171 views

v.clean in QGIS Python console

I have tried to use v.clean and v.clean.advanced (by GRASS GIS) within a script in QGIS, and was not able. I followed instructions here:, but was not able to do so. I got message: "No module named ...
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1answer
501 views

QGIS Invalid object name 'geometry_columns' QODBC3:Unable to execute statement

I was using Lisboa 1.8 with SQL Express and tables with geometry. Connections were working with 1.8 and are working with ArcGIS, so I know my tables and geometry are fine. I installed 2.4 Chugiak, ...
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0answers
29 views

Why does image resolution decrease when I import an image into the georeferencer?

I'm using QGIS 1.8.0 on Windows 7. Usually the georeferencer functions very well. However, when I try to import a particular aerial photograph (in either .tif or .jpg format) the resolution of the ...
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2answers
311 views

QGIS – Raster Calculator: Using flat (no data) areas of an aspect-raster in the raster calculator

I´m playing around with the Raster tools, following more or less the qgis-tutorial but using my own data. When I calculate the aspect of a DEM, flat areas are (logically) left without data. However, ...
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1answer
75 views

Why does QGIS add decimals when a csv is saved as a shapefile?

When I save a csv as shapefile the fields with decimals are saved adding decimals, then the new table in some case has new values. Old Table (CSV) ALTURA ELI ALTURA ORT 1.94 39.6 -11.19 ...
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2answers
912 views

Cropping or removing borders (not NoData) from multiple scanned and georeferenced maps (ArcMap or QGIS)

I have several hundred scanned maps in TIFF format, each correctly georeferenced and forming a large grid of images. The problem is that the border for each map is present - a white band, with a black ...
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244 views

How do I automatically generate a spatial data catalogue from shape files and .gdbs?

I've recently inherited a whole bunch of spatial data (mostly shapefiles but some .gdbs) which relate to a bunch of different cities. I'm looking for a way to take an inventory of what data I've got ...
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0answers
784 views

Clip or Intersection tool - QGIS giving empty files [closed]

I am trying to clip an Ordnance Survey Master Map (OSMM) feature based on a polygon created for the sake of clipping which does not have any attributes, but the output is an empty file. Projection of ...
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1answer
170 views

who to contact about issues with geoserver plugin for qgis

I have a project in QGIS that I am trying to publish using GeoServer via the plugin. When I try and publish a layer I get: global name 'provider' is not defined Traceback (most recent call last): ...
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1answer
38 views

Remove specific simple markers (multiple markers for some US states that are not fully connected)

This is a follow-up of How to create a gradient color expression in data defined properties How can I remove specific centroid simple markers? For example, Florida, Kentucky, and Rhode Island all ...
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2answers
1k views

How to create a gradient color expression in data defined properties

This question is stemming from my other question on data defined attributes: How to create a gradient point on top of a shape file? Anyway, can anyone help me create an expression within the data ...
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1answer
754 views

PyQGIS: Print Composer Map with Table

I am looking for a way to print a custom feature form created in PyQt Designer for QGIS 2.4 using PyQGIS. My goal is to print/save image as the current extent of the map with the selected feature's ...
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1answer
1k views

How to determine bounding box of current qgis 'map canvas extent' from the python console

I've asked a similar question here: How to quickly calculate bounding box coordinates of a selected polygon with qgis ...regarding a quick way to determine the bounding box of a given layer. Is ...
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1answer
44 views

Is there a way to visually clip a layer in QGIS to prevent information from rendering outside the boundary?

In ArcGIS you are able to Clip to Shape, meaning you can use a shapefile to visually clip anything outside if it. This option does not physically clip anything, nor make a new shapefile. For ...
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2answers
175 views

How to create a gradient point on top of a shape file?

I am attempting to create a point that scales in relative size to a particular integer (frequency) and is gradiented to a particular integer value, and then overlay that point onto each specific ...
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1answer
430 views

How to handle “illegal data type (Float64)” error when trying to convert .tif to .bil?

Each time I try to convert (in QGIS 2.2) an elevation model from .tif to .bil format a get this error: ERROR 1: Attempt to create ESRI .hdr labelled dataset with an illegal data type (Float64). ...
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1answer
470 views

Issue using Matplotlib in QGIS

I am developing a QGIS-plugin and for graphing I want to use matplotlib, like many other QGIS -plugins. This worked fine under linux, but under windows with QGIS2.4 I am experiencing problems. I ...
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1answer
290 views

Gridding a LiDAR point cloud? [duplicate]

I have been trying to grid a point cloud, version1.2, LiDAR datasets which are intended to be used for hydraulic simulation of flood propagation. Already, I have used Arc* to work on the traditional ...
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1answer
807 views

Raster and vector layer in the same CRS don't match

While adding multiple raster and vector layers (and setting them all in CRS WGS84) in QGIS 2.2, they don't seem to overlap. Interestingly enough, only raster files overlap between each other, the same ...
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1answer
270 views

Raster map calculation

I figured out a way to filter a raster by using the r.mapcalculator or the raster calculator. The problem is that I have to use Qgis 2.2 because some of my models doesn't work with 2.4. In 2.2 the ...
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2answers
534 views

How to update postgis layer from shapefile in QGIS?

My usual workflow with updating layer from shapefile was to: Open DB Manager; Load SHP files into QGIS; Open DB Manager; Import file (with drop option). Now my problem is that I have created ...
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2answers
803 views

Creating a DEM from CAD contour polylines

Is it at all possible generate a digital elevation model raster from CAD contour polylines with elevations? I am using straight AutoCAD 2014, not Map3D or Civil3D. I was able to bring the dxf of ...
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1answer
100 views

QGIS to solve projection mystery in Postgresql

I downloaded some data from local agency. Per QGIS 2.2, I defined the projection to 'EPSG:3587 - NAD83(NSRS2007) / Michigan Central' in postgresql (maybe ArcMap). Data is in Postgresql 9.3. I am ...
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1answer
7k views

Cut polygon shapefile by line shapefile

I have two shapefiles, a polygon shapefile (lake) and a line shapefile (boudary) I want to create a new shapefile "polygon to the north of the boundary" What tool can I use in QGIS or other free ...
2
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1answer
124 views

Programmatically setting ui for QGIS via setEditForm()

I've been following this thread in attempts to configure my ui preferences programmatically. I've had no issues with loading styles (which subsequently sets the custom ui if I saved it this way), but ...
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1answer
312 views

distance difference in Google Earth with exported GPX or KML compared to source shapefile

I've converted a shapefile (points) to KML with QGIS. Points in the shapefile are within 100m distance from each other. When I measure it in Google Earth, the distance changes to 80m. The same ...
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2answers
258 views

How to bulk print maps using ArcGIS or QGIS?

I have a polygon layer that I would like to print images or PDFs from in bulk as there are a large number of them. Rather than having to manually scroll and print each individual'site' in the print ...
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1answer
444 views

Translate coordinates in GeoJSON export

I am wondering if there is a way to apply a translation in coordinates for a GeoJSON export. Currently, there are negative coordinate values in my export, which I cannot have. I am trying to use ...
3
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2answers
609 views

How to set NULL as default value for a date field in QGIS 2.4?

In QGIS 2.4, i am unable to set the default value as NULL if i have not updated any value on date fields. Its automatically taking the current system date. I am expecting to set the default ...
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1answer
106 views

Help choosing an appropriate GIS solution for the following question [closed]

I am currently researching for an appropriate GIS solution. My requirements are pretty simple: Ability to create circles, symbols or diagrams with transparancy tied to their geographical location ...
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1answer
219 views

Adding shapefile elevation data to dted

I am a newbie to QGIS. Currently trying to augment a dted raster value file with vector shapefile(polygon) containing height of buildings. Have converted the shapefile into raster via rasterize ...
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0answers
35 views

svg export not keeping line widths

I just upgraded to 2.4 I have noticed that when I export as an svg, for opening in illustrator, the line/pen/border widths are coming out all different. For example a line width of 0.25 in QGIS is ...
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1answer
855 views

How to save and load vector layer attribute value map, editable state in .qml style file?

I just upgraded to Qgis 2.4 and there were problems with style file: When I load style file for Qgis <= 2.2, the color of features is right but when I edit them, the value map (value - ...
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1answer
374 views

Error using 'Join attributes by location' via Python

Trying to run a simple script using qgis:joinbylocation but getting either errors or it's not processing correctly. I don't want to take a summary of the attributes, just the attributes of the first ...
3
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0answers
340 views

Why does multi-threaded rendering not use all the CPU potential in QGIS 2.4?

I have just downloaded QGIS 2.4 which is great and ran some tests. I have enabled the multi-threaded rendering but it seems that the program do not use all the potential of my CPU. Attached pic shows ...
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2answers
117 views

How to use values such as 2014-03-31T15:00:33.000Z in QGIS Time Manager?

I´m trying to use the QGIS Time Manager plugin but I have a problem with my attribute columns. Time Manager supports %Y-%m-%d %H:%M:%S format but my dataset uses the following format in the timestamp ...
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0answers
197 views

Standalone QGIS application - handling QgsVectorLayer load errors

I am creating an application with QGIS libraries, and in the event that the app can't add a specified layer (e.g. no connection to host, no password specified etc), it causes the app to crash, ...
3
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1answer
562 views

Calculating the fractal dimension of a line segment

I have a shp file with hundreds of features that represent clipped segments of coastline. Each segment is made up of many vertices (dozens, perhaps even hundreds). (FYI, the segments were created by ...
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0answers
171 views

makefile generated using QGIS Plugin builder cannot find pyuic4

I have QGIS 2.4 installed using the OSGeo4W installer. I have the bin folder in my path and I can run pyuic4 successfully on the command line using osgeo4w.bat, but when I try to run the makefile ...
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1answer
387 views

Replacing PyQt4 with PySide with standalone QGIS

I would like to develop an application using the QGIS libraries and PySide instead of PyQt4 due to more flexible licencing, I wonder if this is possible. I downloaded PySide and replaced my ...
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1answer
529 views

How to install QGIS 2.2 instead of 2.4 to get a working OpenLayers plugin again?

I use ubuntu . I don't know how to return installed qgis 2.2 I try uninstall qgis 2.4 and try find how to install old version qgis 2.2 Please .. tell me how to install old version qgis 2.2 for ubunut ...
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0answers
28 views

QGIS --> ArcGIS server by WMS? [duplicate]

I have found this post: Quantum GIS ->ArcGIS Server configuration possible? My question is more specific >> Can I publish feature layers to ArcGIS server from QGIS using WMS?
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1answer
648 views

How to install PostGIS Manager and RT Sql Layer plugins in QGIS 2.4?

This might be a rather simple question, but both plugins are not visible in my QGIS menu. I'm running 2.4 on Ubuntu 14.04. Thanks for every piece of advice.
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1answer
299 views

How to interact with other layers in a QGis Python init function?

I am using QGis and making a Python script that sets the Python Init function to a custom UI file. I have a function with the following signature: def formOpen(dialog, layer, feature): ... I ...
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95 views

QGIS view bounding box on Add vector layer GeoGSON protocol?

Our server can serve GeoJSON with an optional bounding box HTTP parameter. e.g. http://our_gis_server.org.au/layername?bbox=xmin,ymin,xmax,ymax In QGIS I can add this vector layer as a Protocol and ...