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

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3
votes
1answer
131 views

What is the replacement for 'setColorShadingAlgorithm' in QGIS 2.6?

I have been struggling with setting the colorshadingalgorithm for a raster layer in QGIS with no success for the past few days. The QGIS cookbook seems to be pretty outdated. Anyways, the code that I ...
3
votes
1answer
89 views

How to combine several datapoints in one location to a single point varying in size accordingly?

This might be a very simple thing, but I just can't figure it out how to do it in QGIS (alternatively I'm also grateful for explanations for ArcGIS). I have a fisheries dataset with multiple catches ...
3
votes
2answers
8k views

How to visualize grd files in QGIS?

How to visualize grd files in the software QGIS?
3
votes
2answers
4k views

How to load MrSID raster layer in QGIS on Mac OS?

I have just upgraded QGIS to 2.0 and now I can't load my SID raster layers. I now remember that getting them into 1.8 was a performance but I can't remember all the details. I have downloaded the ...
3
votes
2answers
476 views

Display two-dimensional color gradient for two different quantities

I have two overlapping raster layers. One contains quantity A from 0 to 100, and the other contains quantity B from 0 to 100. I'd like to create a map displaying both sets of data at once based on a ...
3
votes
1answer
146 views

Tilted projection in QGIS

I'm trying to add tpers projection as a custom projection in QGIS 2.10.1 In the Custom crs dialog I'm adding the proj.4 text: +proj=tpers +h=500000000 +lat_0=19 +lon_0=99 +x_0=0 +y_0=0 +a=6371000 +b=...
3
votes
2answers
1k views

How to reproject from Michigan Georef to WGS84 in QGIS?

I am trying to reproject a michigan state land shapefile which is the NAD83/ Michigan Oblique Mercator EPSG:3078 to the WPG84 EPSG:4326 projection. However when i try to do this my map gets squished ...
3
votes
4answers
367 views

Plugin causes QGIS to crash on startup

I get the message "the plugin will be disabled because it crashed QGIS during last startup." Which plugin? None is identified. I'm a bit of a rookie so not sure where to look to solve this. Running on ...
3
votes
1answer
956 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
15k views

How to fix python ImportError: DLL load failed: The specified module could not be found?

During import fiona, I am getting following error. Error is different from other user so I asked this question may be it is repeated. import fiona Traceback (most recent call last): File "D:/...
3
votes
1answer
110 views

How to create a printable data sheet when using edit widget “value realtion” in QGIS 2.0?

I created a spatiaLite Database with a point layer (every point is a tree). Additional I created several tables to fill the columns of the spatial layer with attributes using the editing widget “value ...
3
votes
3answers
847 views

Is it possible to build QGIS with qt5 without changing the code?

I wish to build QGIS using qt5. As told here (Can I use QGIS with Qt5?) it is possible with GIS 2.10. So i've loaded sources from here git://github.com/qgis/QGIS.git and switched to remotes/origin/...
2
votes
2answers
265 views

One-to-many join in QGIS

I am looking for a possibility to make a one-to-many table-join in QGIS. I have a shapefile with postal codes and would like to join them with survey results (more than one). In other words, there ...
2
votes
3answers
1k views

Rasterize line shapefile

I'm trying to convert a line shapefile to a raster image at QGis, but my attempts have been unsuccessful. I've tried to use Raster/Conversion/Rasterize and SAGA/Grid - gridding/Shapes to grid, but to ...
2
votes
1answer
607 views

how to modify shape extents in qgis

I want to change the shape extent of some shape files, I would like to know how to do it in Qgis, since I rasterized some shapes and when I used the calculator to add them, the resulting raster had ...
2
votes
0answers
44 views

Set Snap Mode with PyQGIS

I am trying to set snap mode within QGIS plugin. So far, I have tried: QgsSnappingUtils().setSnapToMapMode(QgsSnappingUtils.SnapAdvanced) and QgsSnappingUtils().setSnapToMapMode(2) without ...
2
votes
2answers
177 views

QGIS - Edit UI - Python Init function localization with QTranslator

I have interaction with layer defined by custom designed UIs. In layer properties the following settings: Edit UI - customline.ui and Python Init function: customline_set.py. #coding: utf8 from ...
2
votes
1answer
795 views

Delete duplicate geometry in postgis tables

After - I dont know what happend - all my entry's in my postgis tables are doubled! I tryed that to delete them but it does not delete any/all duplicates: DELETE FROM planet_osm_point WHERE ...
2
votes
1answer
448 views

How can I solve 'Handle bad layers' error when using OpenStreetMap in Qgis?

I can easy download Portion of maps from OpenStreetMap, save them etc. Once I reopen the same map I get a message that says "Handle bad layers" for all the OSM files. What I am doing wrong?
2
votes
2answers
2k views

QGIS Raster Calculator: Need values to be set to 0 instead of no data

I have a landcover map with different values for the landuse options e.g. 190 for commercially used areas. Now I want to extract only these areas using the Raster Calculator with the expression "...
2
votes
1answer
1k views

Why does my PostGIS query fail with “current transaction is aborted”

I'm trying to create a vector layer in a QGIS project using a PostGIS query. QGIS is returning the following error: Query failed 1 cursor states lost. SQL: CLOSE qgisf1 Result: 7 (ERROR: ...
2
votes
1answer
180 views

How to get mean geographic direction of a polygon in QGIS?

I have a raster height model and would like to calculate the horizontal geographic direction (north, east, etc. - orientation) of each cell, then calculate then the mean value of all these cells in ...
2
votes
1answer
1k views

How do I project a Azimuthal Equidistant global map into a circle in QGIS?

I'm fairly new to QGIS/GIS stuff in general, so I apologize if this is too simple of a question, and I'm just bad at finding my answer. I have a shapefile of all the countries in the globe I ...
2
votes
1answer
89 views

Identify geographic location to points

I am quite new in QGIS and I really need your help. I have a map of Kenya divided into 68 districts and I have coordinates of 30.000 schools. The points have one variable besides the latitude and ...
2
votes
1answer
2k views

Getting polygon shapefile node coordinates and point order

I am trying to get the coordinates of each node of a polygon in QGIS. What I basically did is use the following tools: Vector -> Geometry tools -> Extract nodes Vector -> Geometry tools -> Export ...
2
votes
5answers
4k views

Where to find qgsaffine in the menu?

I installed the plugin qgsaffine but cannot find the entry in the menu bar. Where do I find this. Can anyone here help me with this? best regards desputin
2
votes
2answers
220 views

How do I count the matching 'many' entries in a one-to-many relationship?

I have a simple SHP line file - where each line has a unique reference. I have a related text csv file using the same reference, in a one-to-many situation. I need a map with the lines (in the 'one' ...
2
votes
0answers
95 views

QGIS does not display all Features of Layer and behaves weird instead

I have a weird problem with QGIS trying to load a Layer from a Postgis Database When I open the Layer from Postsgis I have two choices: Method one: Either, I use the Panel "Browser", where I can ...
2
votes
1answer
826 views

QGIS ->ArcGIS Server configuration possible?

Is it possible to connect a QGIS Desktop 1.8.0 to an ArcGIS Server 10.0 ? and of course publish services on it?. The configuration would be like this Quantum GIS-> ArcGIS Server 10.0 on Amazon EC2+ ...
2
votes
0answers
31 views

Unable to change band rendering style of rasters in QGIS 2.10.1 [duplicate]

Apologies, I am new to QGIS and there may exist a simple solution. I have multiple DEM raster files (.tif) added to my map. However, I am unable to alter any of the style options under the "Band ...
2
votes
1answer
2k views

Does QGIS run on Windows Surface with Win RT OS?

I was wondering if anyone has had any success running QGIS on the Windows Surface tablet? Specifically with the Windows RT OS.
2
votes
1answer
107 views

QGIS Print Composer - Display Symbols for Empty Classes?

I am working on a map of mortality rates for several racial/ethnic groups and I have created custom classes to encompass the rates instead of the QGIS classes created through its various modes. This ...
2
votes
2answers
1k views

Using Georeference information stored in tfwx (from ArcGIS) in QGIS?

I have georeferenced some images (ArcGIS -> Update Georeferencing) which creates a *.tfwx file with the new parameters for georeferencing. I renamed it to *.tfw but QGIS is not able to read the ...
2
votes
1answer
232 views

How to apply the same style to different columns?

For many of my datasets I have the same imported data duplicated numerous times, each iteration displaying the data values for a different column (in my case it's fish catch weight per gridded cell ...
2
votes
1answer
250 views

Move label in QGIS?

I cannot figure it out to move Labels in an QGis-Layer. I added two columns (x,y) and set these columns as Data-defined-Position in the layer-properties as descriped in some (older) threads (e.g. How ...
2
votes
1answer
1k views

Problems with Google layers plugins

I currently use Quantum GIS 1.7.4 at work and I have trouble to open Google layers extension. In fact, when I start QGIS 1.7.4 the following message appears and I cannot use Google layers extension. ...
2
votes
2answers
130 views

QGIS Processing - Additional Creation Parameter for GdalWarp

I am having a hard time getting the "Additional Creation Parameters" to work when using GdalWarp through the processing toolbox. I am trying to set the nodata value to 0 for the output raster. ...
2
votes
2answers
617 views

How to use OS Terrain 50 in QGIS

I am new to GIS and I wish to perform view shed analysis of wind turbines from a DEM. I have downloaded OS Terrain 50 and the data is contained within numerous zipped folders. I am using a Mac with ...
2
votes
0answers
511 views

How to use QGIS Accuracy Assessment plugin? [closed]

I am new user and i want perform accuracy assessment in qgis. I have 1 classified map and another for validation. I have installed the plugin. what am i doing after? Plugin: http://plugins.qgis.org/...
2
votes
2answers
354 views

how to extract overlap from non-dissolved buffer zones in qgis 1.7.4

I have a shapefile with the inventory of all limetree in a region. I made a buffer around each tree. So, the place where buffers overlap each other is the best place to put beehives. Is there a way ...
2
votes
2answers
407 views

Why does the buffer take up whole screen?

I am trying to create buffers around the Hurricane Sandy path I created in QGIS (points are lat/long). I have both points from each day she was tracted and the line I created from it with Points2One....
2
votes
2answers
1k views

How to determine which polygons, if any, points fall within?

I am a amateur at GIS and need some help. I have a group of shapefiles of various areas and an Excel spreadsheet of addresses I have geocoded to points. I want to determine whether each point falls ...
2
votes
1answer
979 views

How to develop c++ standalone QGIS C++ Application

I want to integrate QGIS in QT\C++ application. I try to write basic C++ apllication to render map and build it using MSVC 2010. class PostGisViewer: public QMainWindow { public: PostGisViewer(): ...
2
votes
2answers
208 views

“Phantom” features showing up in QGIS 2.4

I tried searching for this, but am unsure exactly what my problem is. I am using QGIS 2.4 on Windows 8.1. I have a project in which I have been digitizing from OpenMaps. Last night I was doing some ...
2
votes
2answers
781 views

Automating the production of GPS-compatible map tiles from georeferenced raster maps

I have a set of TIFF maps that I want to load onto Garmin GPS 62s units. The maximum size for each tile on the GPS is 3Mb and less than 1 million pixels. I manually produced one tile, following this ...
2
votes
1answer
1k views

How to make GRASS and SAGA tools capable to use in QGIS?

I installed QGIS, GRASS and GDAL by OSGeo4w package, and as I finish the installation, I want to use GRASS tool, I face this problem: But I already installed GRASS and SAGA, how to make those tools ...
2
votes
1answer
519 views

How to create/add features without geometry?

I have a simple SpatiaLite geodb loaded in QGIS with one table. There is a POINT geometry field and some alphanumeric fields. In some cases I can record data about a specific site, but the ...
2
votes
1answer
939 views

Couldn't load SIP Module

After reinstalling QGIS, the desktop program runs but generates the python error "Couldn't load SIP Module Pythin support will be disabled" Because of this error, no plug-ins will load. I found a ...
2
votes
3answers
591 views

Creating legend with new data defined symbols functionality in QGIS?

I have a large geology data set that I need to display using an industry standard set of symbols and colours. The symbols and colours are attributes of the data. I have been using the data defined ...
2
votes
1answer
467 views

How to link my QGIS plugin main class to mouse events from a custom Tool?

I Have two files one is mouseevent.py and the other one main.py. class MouseClick(QgsMapTool): canvasDoubleClicked = QtCore.pyqtSignal(object, object) def __init__(self, canvas,layer,...