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

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92
votes
4answers
67k views

File Geodatabase (*.gdb) support in QGIS?

Following questions: Open Source Tool capable of reading Esri File Geodatabase (.gdb)? How to access file geodatabase in Qgis? How to get FGDB support in GDAL 1.9 without compiling? I have spent ...
13
votes
6answers
13k views

Why do OpenLayers plugin layers appear shifted in QGIS print composer?

I'm having trouble with the OpenLayers Plugin of Qgis and the map composer: If I create an OSM-background layer and if I want to export this, the OSM-Layer looks perfectly all right in the normal ...
54
votes
19answers
13k views

Where to find QGIS tutorials and web resources?

I wish to familiarize myself with the capabilities of QGIS. I have downloaded the program, but apart from basic loading of data, I am lost (even after reading the help file). Can you recommend me ...
29
votes
5answers
44k views

Get list of coordinates for points in a layer?

I've got a layer in QGIS that is comprised of points. Its attribute table doesn't have (show) the corresponding x and y coordinates for each point. Is there a way for me to extract a list of ...
10
votes
3answers
2k views

Cannot run standalone QGIS script

I've been trying, along with this post, to run a script in OSGeo4w Shell, outside of QGIS. But I get the following error: ImportError: No module named qgis.core I have also read the following ...
6
votes
1answer
4k 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 ...
25
votes
1answer
9k views

How to define new custom projections in QGIS?

I'm trying to define a projection in QGIS. I want to add North America Albers Equal Area Conic. From the spatialreference site I copied the proj4 line: +proj=aea +lat_1=20 +lat_2=60 +lat_0=40 +lon_0=-...
8
votes
2answers
5k views

QGIS display world country shape files centered on pacific ocean using Robinson, Miller Cylindrical or other projection

I wish to display a map in QGIS (world country shapefiles) showing all countries but centered on the Pacific area. I am not familiar with Proj4, so is there any way this can be done in QGIS please?
9
votes
4answers
9k views

How to fix QGIS error “Entry Point could not be located”?

Today, after returning from vacations, I started my QGIS 1.7 and got this terrible message: Help, anyone?
65
votes
5answers
34k views

How to build effective heat-maps?

Using ArcGIS, QuantumGIS, Grass, and/or GVSIG What are some of the tools and processes involved in building effective heat maps? What are the plugins involved? What are the major data requirements? ...
17
votes
8answers
12k views

How to georeference a vector layer with control points?

I have a non-georeferenced vector layer that I need to be georeferenced. With raster layers the task is easy and straightforward, but I have no idea what should I do with my vector layer. I have a few ...
32
votes
10answers
33k views

Removing small spaces (slivers) between polygons?

I have a set of polygons representing administrative districts. The districts were digitized by hand, and there are small spaces (slivers) between polygons where the polygons should be touching. How ...
16
votes
5answers
8k views

Creating equidistant points in QGIS?

I am trying to create points (new layer) at specific distance along the road (existing layer) in QGIS. Creating Regular points every meter at county level using ArcGIS Desktop? gives solution for ...
18
votes
5answers
23k views

Changing CSV layer attribute value from text to number in QGIS?

I read in a CSV file for linking to a .shp file. All the variables that are just numbers came in as text. How do I change the text variables to numeric in QGIS?
7
votes
4answers
5k views

Dissolve ploygons in QGIS or Grass to new polygons of defined population sizes

I have a shapefile with 3800 polygons representing the smallest administrative areas in Ireland. Many of these, in rural areas, have tiny populations, under 100 people. In urban areas, all would have ...
7
votes
2answers
20k views

How to calculate polygon areas and perimeters using QGIS?

Using QGIS, if I load a polygon layer and make a new column, how do I fill that column with the: area of each polygon and another column with length of the perimeter of each polygon?
36
votes
3answers
76k views

How to merge multiple layers to one layer using QGIS?

I've imported several shapefiles which where exported from an Mapinfo .tab. Several tab files are imported resulting in 20+ layers. Afterwards I want to export it to geoJSON; but I'm reluctant for ...
36
votes
4answers
35k views

How to clip a raster with vector boundaries?

I am using QGIS. I would like to clip a raster precipitation layer using an admin boundary layer that is vector data. However the geoprocessing tools seem to be usable only for vector data. How can ...
21
votes
2answers
22k views

How to reproject a vector layer in QGIS?

I have some shape file which is in UTM. I wanted them to convert to Decimal Degrees in QGIS.
5
votes
1answer
13k views

Elseif Conditional Statement in QGIS Field Calculator

I am trying to write an ELSEIF conditional statement in QGIS Field Calculator (version 1.8.0). I have used an example I found online: CASE WHEN val < 0 THEN 'negative' WHEN val = 0 THEN "neutral'...
4
votes
5answers
5k views

Unable to install ECW support on lubuntu 14.04

I try unsuccessfully to install the ECW support (mainly to use ECW file in QGIS 2.2). We attempt to follow and adapt the howto provided by makina-corpus. My first supprise was the repository ...
10
votes
2answers
2k views

Why are heatmaps on qgis 2.8.1 produced in the wrong CRS?

I noticed that the heatmap calculation on the new upgrade version of qgis is given the raster map without any coordinate system. Have you got the same problem?
26
votes
1answer
3k views

How to draw perpendicular lines in QGIS?

I have a situation like this: What I need to do is to connect each point to every line that is at most, let's say 200 m, away from the point. In other words, I need to draw a perpendicular line ...
29
votes
3answers
56k views

How to calculate polygon areas in QGIS?

Hi I would like to simply calculate areas of a area-shape file in square meters or in acres (ha). I didn't find that functionality in the vector tools. Could anyone here help me with that?
10
votes
6answers
15k views

Joining multiple records to single feature using QGIS?

apologies for what I'm guessing is a really easy problem to solve. GIS user, not programmer here. I'm trying to create a join/relate in QGIS where I have a shapefile of buildings and to that I would ...
10
votes
5answers
15k views

Can QGIS read an ODBC connection?

I have a co-worker who manages a large MS Access database that contains X & Y fields for various locations he tracks. We have previously exported the data to CSV and used the QGIS Delimited Text ...
5
votes
1answer
1k views

Raster incorrectly reprojected to OSGB(27700)

Ubuntu 12.04, QGIS 1.8.0, GDAL/OGR 1.7.3, GEOS 3.2.2 Open a Spatialite db with OS Mastermap poly layer (EPSG:27700); Add OpenLayers Plugin (1.0) from QGIS offical repository; Add a Google Satellite ...
12
votes
3answers
13k views

How to add Direction and Distance to attribute table?

anyone who can help. i just want to add direction (Bearing: i.e N 25 35 E) and Distance (Length: 125 meters) as my new field in polyline/line data. is there a plug-in to generate these fields? i tried ...
14
votes
5answers
11k views

How to create points in a specified distance along the line in QGIS?

I want to use QGIS creating points along the line, but in specified distance. I found two GRASS tools in SEXTANTE Toolbox: v.to.points v.segment I tried v.to.points, setting the maximum distance ...
6
votes
2answers
2k views

How can I access `processing` with Python?

I want to access the explode lines function in Python outside of QGIS from a standalone script. What module do I have to load in order to use it? How can I access processing? from qgis.core import * ...
21
votes
9answers
31k views

How to convert KML to shapefile without losing attributes using QGIS?

I'm new to QGIS and all geoinformation itself but have to work on some difficult stuff. I have a KML file with hundreds of points. To each point there is information, such as Name, Power, Age (it's a ...
11
votes
1answer
11k views

How do I calculate the latitude and longitude of points using QGIS?

I'm trying to figure out how to calculate the lat/long of points using the QGIS field calculator. Is there an easy way to do this? I saw a previous related question, but it deals with a more advanced ...
13
votes
3answers
6k views

How to programatically check for a mouse click in QGIS

I want to know how to check for a mouse click in QGIS. I am trying to write a python plugin and want to provide functionality similar to the "Select Single Feature" tool that already exists in QGIS. ...
8
votes
2answers
10k views

ECW for QGIS 1.8 in Ubuntu 12.04

I have followed various online help guides on how to make ecw for QGIS 1.8 work in Ubuntu 12.04. I had it all working in Ubuntu 10.04 but since migration to 12.04 no such luck. Is there a guide that ...
12
votes
3answers
14k views

Converting Polygon into single or all Points using QGIS?

I want to convert polygons into points using QGIS. I know how it's done in ArcGIS Desktop.
13
votes
0answers
7k views

Is it possible to export geospatial PDF from QGIS via GDAL/OGR? [duplicate]

Is there any plugin for QGIS which would help me in exporting the map document as a geospatial PDF (similar to Terrago's GeoPDF)?
19
votes
4answers
8k views

Joining attributes from nearest point in QGIS?

I have two layers with points, call them A and B, each with different attributes. For each point in A I want to join all the attributes from the nearest point in B. Ideally this would also include ...
24
votes
9answers
54k views

How to import a DWG into a QGIS project?

I have a lot of DWG files like base map, and water and wastewater network. I am lookin for the principal steps to import my files into my QGIS project.
35
votes
3answers
17k views

How to make a spatial view in PostGIS and add it as a layer in QGIS?

In PostGIS 2.0, what is the most efficient way to create a spatially enabled view that is viewable in QGIS? I followed the context of Part 2 of @Mike Toews answer to this question, and the view ...
10
votes
6answers
6k views

How to get “.GDB” Esri File Geodatabase in QGIS for MAC OSX 10.6?

I understand there are programs like OSGeo4W that allow windows users to work with File Geodatabases, but is there something similar for Mac OSX?
16
votes
4answers
33k views

How to convert a vector layer to raster?

In qgis in the raster menu there is an item "convert vector to raster". This behaves strangely - I do not understand how it is supposed to work. I can select a vector file, an attribute and an ...
6
votes
5answers
2k views

How to Digitize Free Satellite Imagery in QGIS - Alignment issues with Openlayers Plugin

I am trying to digitize OpenLayers data (such as Google satellite imagery) with no success. Whenever I try to move or zoom the canvas the vector layer I digitized loses the position relative to the ...
5
votes
4answers
4k views

Cannot see OpenLayers under Plugin in QGIS?

Although I have installed the OpenLayers plugin in QGIS 2.4, I cannot see it in the list when I click on Plugins. Does anyone else have this issue?
15
votes
3answers
6k views

How to calculate Network Service Areas in QGIS?

Is there any way in QGIS to apply service area buffers e.g if I have a point on a map I wish to show the service coverage of 1 mile, 2 mile, 3 mile, breaks using the road network?
24
votes
4answers
35k views

How do I load OSM vector data in QGIS 2.x?

In QGIS 1.8 I used the openstreetmap plugin to request data from the server, or open a .osm XML file, which produced 3 layers (polygons, polylines and points) in QGIS. This was great (give or take the ...
21
votes
4answers
17k views

Creating DEM from contours in QGIS?

Is it possible to make a DEM from contours in QGIS? I have a shp file (contours) and their heights, can I use QGIS for produce a DEM without using GRASS? I found this creating a dem from contours ...
27
votes
7answers
46k views

How do I create point features with exact coordinates?

How do I create point features with exact (manually entered) coordinates in QGIS? I get precise GPS coordinates from a survey team which I need to add to a point layer. What I want: -Add point, type ...
28
votes
4answers
15k views

Joining non-spatial CSV file to spatial data (shapefile) using QGIS?

I have a CSV file which has postcode data in a field, but it is non-spatial e.g. no Easting and Northing. I have a shapefile with postcode in a field and some additional data. I want to join the ...
13
votes
4answers
3k views

Elevation profile 10 km each side of a line

How can I get an elevation profile for a band of terrain? The highest elevation within 10 km (on each side of the defined line) should be taken into account. I hope my question is clear. Thank you ...
7
votes
4answers
11k views

Viewing LIDAR data (.las) in QGIS?

Is there an easy path to visualizing LIDAR data in QGIS? I have some USGS LIDAR data in .las format downloaded from http://lidar.cr.usgs.gov/. This means I have both the .las and metadata in .xml ...