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

learn more… | top users | synonyms (1)

65
votes
3answers
41k 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 ...
7
votes
4answers
7k 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?
54
votes
6answers
25k 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? ...
21
votes
5answers
26k 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 ...
52
votes
17answers
8k 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 ...
20
votes
1answer
5k 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 ...
10
votes
5answers
14k 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?
21
votes
3answers
21k 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 ...
4
votes
4answers
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 ...
11
votes
4answers
5k views

How to create equidistant points in QGIS?

I am trying to create points (new layer) at specific distance along the road (existing layer) in QGIS. This gives solution for ArcGIS. How to achieve this in QGIS? This one explains how to create ...
9
votes
5answers
10k views

How to join multiple records to single feature?

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 ...
7
votes
2answers
2k 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
2answers
7k 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 ...
16
votes
5answers
11k views

Is it possible to make a 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 find this creating a dem from contours but ...
10
votes
7answers
7k 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 ...
10
votes
5answers
10k 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
803 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 ...
22
votes
7answers
22k 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 ...
19
votes
3answers
37k 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 ...
11
votes
5answers
9k views

How to perform Raster Reclassification in QGIS?

Is there a way to do reclassify a raster image to Qgis? In Arcgis you can do that in Spatial analyst Tools→Reclass→Reclassify Any ideas?
5
votes
6answers
5k views

How to georeference a dxf?

I have got myself a dxf which is built with units in the wrong scale. How do I upscale that in QGIS? Note it does open in QGIS, just in the wrong map units and location.
14
votes
9answers
19k views

How to convert KML to shapefile without losing attributes?

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 ...
15
votes
9answers
28k 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.
21
votes
2answers
30k 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?
8
votes
5answers
4k 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 ...
8
votes
6answers
5k 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?
7
votes
2answers
8k 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 ...
4
votes
2answers
7k views

Viewing .las format LIDAR data in QGIS?

Is there an easy path to visualizing this LIDAR data? I have QGIS, and some USGS LIDAR data in (.las) format downloaded from http://lidar.cr.usgs.gov/ . This means I have both the (.las) and ...
4
votes
1answer
5k 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 ...
3
votes
1answer
571 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 ...
13
votes
2answers
11k 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. Thanks.
7
votes
2answers
397 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?
16
votes
1answer
2k 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 ...
22
votes
1answer
17k views

How to install a QGIS plugin when offline?

Due to various IT policies at my workplace, QGIS is installed on a machine that is not connected to the internet. I wish to install a couple of QGIS plugins on this system. I have downloaded the ...
19
votes
2answers
10k views

How to convert .shp into .gpx using QGIS?

I'm newbie using QGIS. I would like to convert .shp into .gpx. So, using Qgis, I open my shapefile and I tried to "save as" gpx but it gives an OGR error: creation of field ObjectId failed (OGR ...
10
votes
4answers
2k 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 ...
11
votes
4answers
4k views

Is it possible to export GeoPDF from QGIS?

Is there any plugin for QGIS which would help me in exporting the map document as a GeoPDF ?
5
votes
5answers
3k views

How to calculate distances in a point sequence?

I'm looking for help calculating the distance between a sequence of points that are in a single Shapefile in QGIS. Below is what my data look like and a blank distance column I've added to show how ...
3
votes
2answers
2k views

Colouring areas between (vector) contours?

Is it possible to colour areas between (vector) contours without making it a DEM first? Joshdoe seems to have done so in Create filled contour map with GRASS but does not say how.
11
votes
3answers
18k 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 ...
7
votes
2answers
10k 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?
8
votes
8answers
7k views

Splitting shapefile into separate shapefiles for each feature using QGIS/GDAL/SAGA?

I have a polyline shapefile with about 20 kinds of roads. I would like to know how can I create automatically a vector file for each one. I am aware of how to do it using ArcGIS for Desktop - see ...
4
votes
2answers
1k views

How to automatically reloaded raster layer if source is changed in QGIS?

How to automatically reloaded raster layer if source is changed? (The path is the same but inside source file are changes) I use: qgis.utils.iface.mapCanvas().refresh() but layer not refresh. # ...
22
votes
3answers
15k views

How to convert ArcGIS .mxd file to QGIS .qgs file?

I recently tried to use QGIS and I wondered if you can convert a draft ArcGIS map (*.mxd file) into a QGIS project (*.qgs file). This would avoid thematize the entire project.
18
votes
5answers
23k 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 ...
7
votes
1answer
13k views

How to crop Shapefiles in QGIS?

I need to clip a large and very detailed .shp file in QGIS showing environmental data similar to a temperature map. Is there something like the very simple crop tool alike in photoshop where you can ...
6
votes
2answers
380 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 ...
8
votes
5answers
7k views

How do I convert a Polygon into a single or all Points?

I want to convert polygons into points. I know how it's done in ArcGis and I think this may sound trivial but it's a serious issue :/. I'll appreciate any hints :)
6
votes
4answers
3k views

Why do OpenLayers layers appear shifted in map 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 ...
6
votes
1answer
4k views

How to create a point along a line given distance

I have been given a non-spatial database which contains the names of lines which I have a shapefile for. The database also has names of points and the distance of each point from the origin along the ...